**Proportional Hazards Models**: Statistical models used in survival analysis that assert that the effect of the study factors on the hazard rate in the study population is multiplicative and does not change over time.

**Risk Factors**: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.

**Cohort Studies**: Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.

**Follow-Up Studies**: Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.

**Prospective Studies**: Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.

**Prognosis**: A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.

**Survival Analysis**: A class of statistical procedures for estimating the survival function (function of time, starting with a population 100% well at a given time and providing the percentage of the population still well at later times). The survival analysis is then used for making inferences about the effects of treatments, prognostic factors, exposures, and other covariates on the function.

**Kaplan-Meier Estimate**: A nonparametric method of compiling LIFE TABLES or survival tables. It combines calculated probabilities of survival and estimates to allow for observations occurring beyond a measurement threshold, which are assumed to occur randomly. Time intervals are defined as ending each time an event occurs and are therefore unequal. (From Last, A Dictionary of Epidemiology, 1995)

**Incidence**: The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases, new or old, in the population at a given time.

**Retrospective Studies**: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.

**Survival Rate**: The proportion of survivors in a group, e.g., of patients, studied and followed over a period, or the proportion of persons in a specified group alive at the beginning of a time interval who survive to the end of the interval. It is often studied using life table methods.

**Multivariate Analysis**: A set of techniques used when variation in several variables has to be studied simultaneously. In statistics, multivariate analysis is interpreted as any analytic method that allows simultaneous study of two or more dependent variables.

**Risk Assessment**: The qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences. (Last, Dictionary of Epidemiology, 1988)

**Time Factors**: Elements of limited time intervals, contributing to particular results or situations.

**Treatment Outcome**: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.

**Predictive Value of Tests**: In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.

**United States**

**Risk**: The probability that an event will occur. It encompasses a variety of measures of the probability of a generally unfavorable outcome.

**Cause of Death**: Factors which produce cessation of all vital bodily functions. They can be analyzed from an epidemiologic viewpoint.

**Age Factors**: Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.

**Neoplasm Staging**: Methods which attempt to express in replicable terms the extent of the neoplasm in the patient.

**Confidence Intervals**: A range of values for a variable of interest, e.g., a rate, constructed so that this range has a specified probability of including the true value of the variable.

**Disease-Free Survival**: Period after successful treatment in which there is no appearance of the symptoms or effects of the disease.

**Longitudinal Studies**: Studies in which variables relating to an individual or group of individuals are assessed over a period of time.

**Mortality**: All deaths reported in a given population.

**Breast Neoplasms**: Tumors or cancer of the human BREAST.

**Cardiovascular Diseases**: Pathological conditions involving the CARDIOVASCULAR SYSTEM including the HEART; the BLOOD VESSELS; or the PERICARDIUM.

**Registries**: The systems and processes involved in the establishment, support, management, and operation of registers, e.g., disease registers.

**Japan**

**SEER Program**: A cancer registry mandated under the National Cancer Act of 1971 to operate and maintain a population-based cancer reporting system, reporting periodically estimates of cancer incidence and mortality in the United States. The Surveillance, Epidemiology, and End Results (SEER) Program is a continuing project of the National Cancer Institute of the National Institutes of Health. Among its goals, in addition to assembling and reporting cancer statistics, are the monitoring of annual cancer incident trends and the promoting of studies designed to identify factors amenable to cancer control interventions. (From National Cancer Institute, NIH Publication No. 91-3074, October 1990)

**Smoking**: Inhaling and exhaling the smoke of burning TOBACCO.

**Questionnaires**: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.

**Sex Factors**: Maleness or femaleness as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or effect of a circumstance. It is used with human or animal concepts but should be differentiated from SEX CHARACTERISTICS, anatomical or physiological manifestations of sex, and from SEX DISTRIBUTION, the number of males and females in given circumstances.

**Disease Progression**: The worsening of a disease over time. This concept is most often used for chronic and incurable diseases where the stage of the disease is an important determinant of therapy and prognosis.

**Neoplasm Recurrence, Local**: The local recurrence of a neoplasm following treatment. It arises from microscopic cells of the original neoplasm that have escaped therapeutic intervention and later become clinically visible at the original site.

**Confounding Factors (Epidemiology)**: Factors that can cause or prevent the outcome of interest, are not intermediate variables, and are not associated with the factor(s) under investigation. They give rise to situations in which the effects of two processes are not separated, or the contribution of causal factors cannot be separated, or the measure of the effect of exposure or risk is distorted because of its association with other factors influencing the outcome of the study.

**Tumor Markers, Biological**: Molecular products metabolized and secreted by neoplastic tissue and characterized biochemically in cells or body fluids. They are indicators of tumor stage and grade as well as useful for monitoring responses to treatment and predicting recurrence. Many chemical groups are represented including hormones, antigens, amino and nucleic acids, enzymes, polyamines, and specific cell membrane proteins and lipids.

**Kidney Failure, Chronic**: The end-stage of CHRONIC RENAL INSUFFICIENCY. It is characterized by the severe irreversible kidney damage (as measured by the level of PROTEINURIA) and the reduction in GLOMERULAR FILTRATION RATE to less than 15 ml per min (Kidney Foundation: Kidney Disease Outcome Quality Initiative, 2002). These patients generally require HEMODIALYSIS or KIDNEY TRANSPLANTATION.

**Stroke**: A group of pathological conditions characterized by sudden, non-convulsive loss of neurological function due to BRAIN ISCHEMIA or INTRACRANIAL HEMORRHAGES. Stroke is classified by the type of tissue NECROSIS, such as the anatomic location, vasculature involved, etiology, age of the affected individual, and hemorrhagic vs. non-hemorrhagic nature. (From Adams et al., Principles of Neurology, 6th ed, pp777-810)

**Comorbidity**: The presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.

**Recurrence**: The return of a sign, symptom, or disease after a remission.

**Body Mass Index**: An indicator of body density as determined by the relationship of BODY WEIGHT to BODY HEIGHT. BMI=weight (kg)/height squared (m2). BMI correlates with body fat (ADIPOSE TISSUE). Their relationship varies with age and gender. For adults, BMI falls into these categories: below 18.5 (underweight); 18.5-24.9 (normal); 25.0-29.9 (overweight); 30.0 and above (obese). (National Center for Health Statistics, Centers for Disease Control and Prevention)

**European Continental Ancestry Group**: Individuals whose ancestral origins are in the continent of Europe.

**Prostatic Neoplasms**: Tumors or cancer of the PROSTATE.

**Chi-Square Distribution**: A distribution in which a variable is distributed like the sum of the squares of any given independent random variable, each of which has a normal distribution with mean of zero and variance of one. The chi-square test is a statistical test based on comparison of a test statistic to a chi-square distribution. The oldest of these tests are used to detect whether two or more population distributions differ from one another.

**Odds Ratio**: The ratio of two odds. The exposure-odds ratio for case control data is the ratio of the odds in favor of exposure among cases to the odds in favor of exposure among noncases. The disease-odds ratio for a cohort or cross section is the ratio of the odds in favor of disease among the exposed to the odds in favor of disease among the unexposed. The prevalence-odds ratio refers to an odds ratio derived cross-sectionally from studies of prevalent cases.

**Myocardial Infarction**: NECROSIS of the MYOCARDIUM caused by an obstruction of the blood supply to the heart (CORONARY CIRCULATION).

**Renal Dialysis**: Therapy for the insufficient cleansing of the BLOOD by the kidneys based on dialysis and including hemodialysis, PERITONEAL DIALYSIS, and HEMODIAFILTRATION.

**Taiwan**

**Coronary Disease**: An imbalance between myocardial functional requirements and the capacity of the CORONARY VESSELS to supply sufficient blood flow. It is a form of MYOCARDIAL ISCHEMIA (insufficient blood supply to the heart muscle) caused by a decreased capacity of the coronary vessels.

**Biological Markers**: Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.

**Severity of Illness Index**: Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.

**Colorectal Neoplasms**: Tumors or cancer of the COLON or the RECTUM or both. Risk factors for colorectal cancer include chronic ULCERATIVE COLITIS; FAMILIAL POLYPOSIS COLI; exposure to ASBESTOS; and irradiation of the CERVIX UTERI.

**Lung Neoplasms**: Tumors or cancer of the LUNG.

**Lymphatic Metastasis**: Transfer of a neoplasm from its primary site to lymph nodes or to distant parts of the body by way of the lymphatic system.

**Epidemiologic Methods**: Research techniques that focus on study designs and data gathering methods in human and animal populations.

**Postmenopause**: The physiological period following the MENOPAUSE, the permanent cessation of the menstrual life.

**Diet**: Regular course of eating and drinking adopted by a person or animal.

**HIV Infections**: Includes the spectrum of human immunodeficiency virus infections that range from asymptomatic seropositivity, thru AIDS-related complex (ARC), to acquired immunodeficiency syndrome (AIDS).

**Heart Failure**: A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (VENTRICULAR DYSFUNCTION), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as MYOCARDIAL INFARCTION.

**Hospitalization**: The confinement of a patient in a hospital.

**Neoplasms**: New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.

**African Americans**: Persons living in the United States having origins in any of the black groups of Africa.

**Sweden**

**Regression Analysis**: Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.

**Adenocarcinoma**: A malignant epithelial tumor with a glandular organization.

**Age Distribution**: The frequency of different ages or age groups in a given population. The distribution may refer to either how many or what proportion of the group. The population is usually patients with a specific disease but the concept is not restricted to humans and is not restricted to medicine.

**Coffee**: A beverage made from ground COFFEA beans (SEEDS) infused in hot water. It generally contains CAFFEINE and THEOPHYLLINE unless it is decaffeinated.

**Models, Statistical**: Statistical formulations or analyses which, when applied to data and found to fit the data, are then used to verify the assumptions and parameters used in the analysis. Examples of statistical models are the linear model, binomial model, polynomial model, two-parameter model, etc.

**Alcohol Drinking**: Behaviors associated with the ingesting of alcoholic beverages, including social drinking.

**Diabetes Mellitus, Type 2**: A subclass of DIABETES MELLITUS that is not INSULIN-responsive or dependent (NIDDM). It is characterized initially by INSULIN RESISTANCE and HYPERINSULINEMIA; and eventually by GLUCOSE INTOLERANCE; HYPERGLYCEMIA; and overt diabetes. Type II diabetes mellitus is no longer considered a disease exclusively found in adults. Patients seldom develop KETOSIS but often exhibit OBESITY.

**Combined Modality Therapy**: The treatment of a disease or condition by several different means simultaneously or sequentially. Chemoimmunotherapy, RADIOIMMUNOTHERAPY, chemoradiotherapy, cryochemotherapy, and SALVAGE THERAPY are seen most frequently, but their combinations with each other and surgery are also used.

**Finland**

**Antiretroviral Therapy, Highly Active**: Drug regimens, for patients with HIV INFECTIONS, that aggressively suppress HIV replication. The regimens usually involve administration of three or more different drugs including a protease inhibitor.

**Analysis of Variance**: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.

**CD4 Lymphocyte Count**: The number of CD4-POSITIVE T-LYMPHOCYTES per unit volume of BLOOD. Determination requires the use of a fluorescence-activated flow cytometer.

**California**

**Diabetes Mellitus**: A heterogeneous group of disorders characterized by HYPERGLYCEMIA and GLUCOSE INTOLERANCE.

**Vegetables**: A food group comprised of EDIBLE PLANTS or their parts.

**Propensity Score**: Conditional probability of exposure to a treatment given observed covariates.

**Chemotherapy, Adjuvant**: Drug therapy given to augment or stimulate some other form of treatment such as surgery or radiation therapy. Adjuvant chemotherapy is commonly used in the therapy of cancer and can be administered before or after the primary treatment.

**Databases, Factual**: Extensive collections, reputedly complete, of facts and data garnered from material of a specialized subject area and made available for analysis and application. The collection can be automated by various contemporary methods for retrieval. The concept should be differentiated from DATABASES, BIBLIOGRAPHIC which is restricted to collections of bibliographic references.

**Sex Distribution**: The number of males and females in a given population. The distribution may refer to how many men or women or what proportion of either in the group. The population is usually patients with a specific disease but the concept is not restricted to humans and is not restricted to medicine.

**Case-Control Studies**: Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.

**Logistic Models**: Statistical models which describe the relationship between a qualitative dependent variable (that is, one which can take only certain discrete values, such as the presence or absence of a disease) and an independent variable. A common application is in epidemiology for estimating an individual's risk (probability of a disease) as a function of a given risk factor.

**African Continental Ancestry Group**: Individuals whose ancestral origins are in the continent of Africa.

**Denmark**

**Hypertension**: Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.

**Survival**: Continuance of life or existence especially under adverse conditions; includes methods and philosophy of survival.

**Probability**: The study of chance processes or the relative frequency characterizing a chance process.

**Women's Health**: The concept covering the physical and mental conditions of women.

**Food Habits**: Acquired or learned food preferences.

**Prostate-Specific Antigen**: A glycoprotein that is a kallikrein-like serine proteinase and an esterase, produced by epithelial cells of both normal and malignant prostate tissue. It is an important marker for the diagnosis of prostate cancer.

**Life Style**: Typical way of life or manner of living characteristic of an individual or group. (From APA, Thesaurus of Psychological Index Terms, 8th ed)

**Hip Fractures**: Fractures of the FEMUR HEAD; the FEMUR NECK; (FEMORAL NECK FRACTURES); the trochanters; or the inter- or subtrochanteric region. Excludes fractures of the acetabulum and fractures of the femoral shaft below the subtrochanteric region (FEMORAL FRACTURES).

**Liver Neoplasms**: Tumors or cancer of the LIVER.

**Diabetes Complications**: Conditions or pathological processes associated with the disease of diabetes mellitus. Due to the impaired control of BLOOD GLUCOSE level in diabetic patients, pathological processes develop in numerous tissues and organs including the EYE, the KIDNEY, the BLOOD VESSELS, and the NERVE TISSUE.

**Socioeconomic Factors**: Social and economic factors that characterize the individual or group within the social structure.

**Treatment Failure**: A measure of the quality of health care by assessment of unsuccessful results of management and procedures used in combating disease, in individual cases or series.

**Age of Onset**: The age, developmental stage, or period of life at which a disease or the initial symptoms or manifestations of a disease appear in an individual.

**Prostatectomy**: Complete or partial surgical removal of the prostate. Three primary approaches are commonly employed: suprapubic - removal through an incision above the pubis and through the urinary bladder; retropubic - as for suprapubic but without entering the urinary bladder; and transurethral (TRANSURETHRAL RESECTION OF PROSTATE).

**Randomized Controlled Trials as Topic**: Works about clinical trials that involve at least one test treatment and one control treatment, concurrent enrollment and follow-up of the test- and control-treated groups, and in which the treatments to be administered are selected by a random process, such as the use of a random-numbers table.

**Genotype**: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.

**China**: A country spanning from central Asia to the Pacific Ocean.

**Carcinoma, Squamous Cell**: A carcinoma derived from stratified SQUAMOUS EPITHELIAL CELLS. It may also occur in sites where glandular or columnar epithelium is normally present. (From Stedman, 25th ed)

**Ovarian Neoplasms**: Tumors or cancer of the OVARY. These neoplasms can be benign or malignant. They are classified according to the tissue of origin, such as the surface EPITHELIUM, the stromal endocrine cells, and the totipotent GERM CELLS.

**Receptors, Estrogen**: Cytoplasmic proteins that bind estrogens and migrate to the nucleus where they regulate DNA transcription. Evaluation of the state of estrogen receptors in breast cancer patients has become clinically important.

**Residence Characteristics**: Elements of residence that characterize a population. They are applicable in determining need for and utilization of health services.

**Anti-HIV Agents**: Agents used to treat AIDS and/or stop the spread of the HIV infection. These do not include drugs used to treat symptoms or opportunistic infections associated with AIDS.

**Dementia**: An acquired organic mental disorder with loss of intellectual abilities of sufficient severity to interfere with social or occupational functioning. The dysfunction is multifaceted and involves memory, behavior, personality, judgment, attention, spatial relations, language, abstract thought, and other executive functions. The intellectual decline is usually progressive, and initially spares the level of consciousness.

**Biometry**: The use of statistical and mathematical methods to analyze biological observations and phenomena.

**Prevalence**: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.

**Fruit**: The fleshy or dry ripened ovary of a plant, enclosing the seed or seeds.

**Endometrial Neoplasms**: Tumors or cancer of ENDOMETRIUM, the mucous lining of the UTERUS. These neoplasms can be benign or malignant. Their classification and grading are based on the various cell types and the percent of undifferentiated cells.

**Immunohistochemistry**: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.

**Multicenter Studies as Topic**: Works about controlled studies which are planned and carried out by several cooperating institutions to assess certain variables and outcomes in specific patient populations, for example, a multicenter study of congenital anomalies in children.

**Health Surveys**: A systematic collection of factual data pertaining to health and disease in a human population within a given geographic area.

**Stomach Neoplasms**: Tumors or cancer of the STOMACH.

**Diet Surveys**: Systematic collections of factual data pertaining to the diet of a human population within a given geographic area.

**Life Tables**: Summarizing techniques used to describe the pattern of mortality and survival in populations. These methods can be applied to the study not only of death, but also of any defined endpoint such as the onset of disease or the occurrence of disease complications.

**Carcinoma, Hepatocellular**: A primary malignant neoplasm of epithelial liver cells. It ranges from a well-differentiated tumor with EPITHELIAL CELLS indistinguishable from normal HEPATOCYTES to a poorly differentiated neoplasm. The cells may be uniform or markedly pleomorphic, or form GIANT CELLS. Several classification schemes have been suggested.

**Neoplasm Grading**: Methods which attempt to express in replicable terms the level of CELL DIFFERENTIATION in neoplasms as increasing ANAPLASIA correlates with the aggressiveness of the neoplasm.

**Estrogen Replacement Therapy**: The use of hormonal agents with estrogen-like activity in postmenopausal or other estrogen-deficient women to alleviate effects of hormone deficiency, such as vasomotor symptoms, DYSPAREUNIA, and progressive development of OSTEOPOROSIS. This may also include the use of progestational agents in combination therapy.

**Esophageal Neoplasms**: Tumors or cancer of the ESOPHAGUS.

**Netherlands**: Country located in EUROPE. It is bordered by the NORTH SEA, BELGIUM, and GERMANY. Constituent areas are Aruba, Curacao, Sint Maarten, formerly included in the NETHERLANDS ANTILLES.

**Receptors, Progesterone**: Specific proteins found in or on cells of progesterone target tissues that specifically combine with progesterone. The cytosol progesterone-receptor complex then associates with the nucleic acids to initiate protein synthesis. There are two kinds of progesterone receptors, A and B. Both are induced by estrogen and have short half-lives.

**beta Carotene**: A carotenoid that is a precursor of VITAMIN A. It is administered to reduce the severity of photosensitivity reactions in patients with erythropoietic protoporphyria (PORPHYRIA, ERYTHROPOIETIC). (From Reynolds JEF(Ed): Martindale: The Extra Pharmacopoeia (electronic version). Micromedex, Inc, Engewood, CO, 1995.)

**Veterans**: Former members of the armed services.

**Minnesota**

**Neoplasm Invasiveness**: Ability of neoplasms to infiltrate and actively destroy surrounding tissue.

**ROC Curve**: A graphic means for assessing the ability of a screening test to discriminate between healthy and diseased persons; may also be used in other studies, e.g., distinguishing stimuli responses as to a faint stimuli or nonstimuli.

**Coronary Artery Disease**: Pathological processes of CORONARY ARTERIES that may derive from a congenital abnormality, atherosclerotic, or non-atherosclerotic cause.

**Aging**: The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.

**Glomerular Filtration Rate**: The volume of water filtered out of plasma through glomerular capillary walls into Bowman's capsules per unit of time. It is considered to be equivalent to INULIN clearance.

**Carcinoma, Non-Small-Cell Lung**: A heterogeneous aggregate of at least three distinct histological types of lung cancer, including SQUAMOUS CELL CARCINOMA; ADENOCARCINOMA; and LARGE CELL CARCINOMA. They are dealt with collectively because of their shared treatment strategy.

**Data Interpretation, Statistical**: Application of statistical procedures to analyze specific observed or assumed facts from a particular study.

**Kidney Neoplasms**: Tumors or cancers of the KIDNEY.

**Antineoplastic Combined Chemotherapy Protocols**: The use of two or more chemicals simultaneously or sequentially in the drug therapy of neoplasms. The drugs need not be in the same dosage form.

**Creatinine**

**Outcome Assessment (Health Care)**: Research aimed at assessing the quality and effectiveness of health care as measured by the attainment of a specified end result or outcome. Measures include parameters such as improved health, lowered morbidity or mortality, and improvement of abnormal states (such as elevated blood pressure).

**Polymorphism, Single Nucleotide**: A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.

**Reproducibility of Results**: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.

**Medicare**: Federal program, created by Public Law 89-97, Title XVIII-Health Insurance for the Aged, a 1965 amendment to the Social Security Act, that provides health insurance benefits to persons over the age of 65 and others eligible for Social Security benefits. It consists of two separate but coordinated programs: hospital insurance (MEDICARE PART A) and supplementary medical insurance (MEDICARE PART B). (Hospital Administration Terminology, AHA, 2d ed and A Discursive Dictionary of Health Care, US House of Representatives, 1976)

**Radiotherapy, Adjuvant**: Radiotherapy given to augment some other form of treatment such as surgery or chemotherapy. Adjuvant radiotherapy is commonly used in the therapy of cancer and can be administered before or after the primary treatment.

**Death, Sudden, Cardiac**: Unexpected rapid natural death due to cardiovascular collapse within one hour of initial symptoms. It is usually caused by the worsening of existing heart diseases. The sudden onset of symptoms, such as CHEST PAIN and CARDIAC ARRHYTHMIAS, particularly VENTRICULAR TACHYCARDIA, can lead to the loss of consciousness and cardiac arrest followed by biological death. (from Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005)

**Death**: Irreversible cessation of all bodily functions, manifested by absence of spontaneous breathing and total loss of cardiovascular and cerebral functions.

**Pancreatic Neoplasms**: Tumors or cancer of the PANCREAS. Depending on the types of ISLET CELLS present in the tumors, various hormones can be secreted: GLUCAGON from PANCREATIC ALPHA CELLS; INSULIN from PANCREATIC BETA CELLS; and SOMATOSTATIN from the SOMATOSTATIN-SECRETING CELLS. Most are malignant except the insulin-producing tumors (INSULINOMA).

**Brain Neoplasms**: Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.

**Blood Pressure**: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.

**Dairy Products**: Raw and processed or manufactured milk and milk-derived products. These are usually from cows (bovine) but are also from goats, sheep, reindeer, and water buffalo.

**C-Reactive Protein**: A plasma protein that circulates in increased amounts during inflammation and after tissue damage.

**Europe**

**Survivors**: Persons who have experienced a prolonged survival after serious disease or who continue to live with a usually life-threatening condition as well as family members, significant others, or individuals surviving traumatic life events.

**Neoplasm Metastasis**: The transfer of a neoplasm from one organ or part of the body to another remote from the primary site.

**National Institutes of Health (U.S.)**: An operating division of the US Department of Health and Human Services. It is concerned with the overall planning, promoting, and administering of programs pertaining to health and medical research. Until 1995, it was an agency of the United States PUBLIC HEALTH SERVICE.

**Menopause**: The last menstrual period. Permanent cessation of menses (MENSTRUATION) is usually defined after 6 to 12 months of AMENORRHEA in a woman over 45 years of age. In the United States, menopause generally occurs in women between 48 and 55 years of age.

**Ethnic Groups**: A group of people with a common cultural heritage that sets them apart from others in a variety of social relationships.

**Reproductive History**: An important aggregate factor in epidemiological studies of women's health. The concept usually includes the number and timing of pregnancies and their outcomes, the incidence of breast feeding, and may include age of menarche and menopause, regularity of menstruation, fertility, gynecological or obstetric problems, or contraceptive usage.

**Carcinoma, Renal Cell**: A heterogeneous group of sporadic or hereditary carcinoma derived from cells of the KIDNEYS. There are several subtypes including the clear cells, the papillary, the chromophobe, the collecting duct, the spindle cells (sarcomatoid), or mixed cell-type carcinoma.

**Nomograms**: Graphical representation of a statistical model containing scales for calculating the prognostic weight of a value for each individual variable. Nomograms are instruments that can be used to predict outcomes using specific clinical parameters. They use ALGORITHMS that incorporate several variables to calculate the predicted probability that a patient will achieve a particular clinical endpoint.

**Chronic Disease**: Diseases which have one or more of the following characteristics: they are permanent, leave residual disability, are caused by nonreversible pathological alteration, require special training of the patient for rehabilitation, or may be expected to require a long period of supervision, observation, or care. (Dictionary of Health Services Management, 2d ed)

**Obesity**: A status with BODY WEIGHT that is grossly above the acceptable or desirable weight, usually due to accumulation of excess FATS in the body. The standards may vary with age, sex, genetic or cultural background. In the BODY MASS INDEX, a BMI greater than 30.0 kg/m2 is considered obese, and a BMI greater than 40.0 kg/m2 is considered morbidly obese (MORBID OBESITY).

**Biostatistics**: The application of STATISTICS to biological systems and organisms involving the retrieval or collection, analysis, reduction, and interpretation of qualitative and quantitative data.

**Double-Blind Method**: A method of studying a drug or procedure in which both the subjects and investigators are kept unaware of who is actually getting which specific treatment.

**Pregnancy**: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.

**Genetic Predisposition to Disease**: A latent susceptibility to disease at the genetic level, which may be activated under certain conditions.

**Population Surveillance**: Ongoing scrutiny of a population (general population, study population, target population, etc.), generally using methods distinguished by their practicability, uniformity, and frequently their rapidity, rather than by complete accuracy.

**Dietary Supplements**: Products in capsule, tablet or liquid form that provide dietary ingredients, and that are intended to be taken by mouth to increase the intake of nutrients. Dietary supplements can include macronutrients, such as proteins, carbohydrates, and fats; and/or MICRONUTRIENTS, such as VITAMINS; MINERALS; and PHYTOCHEMICALS.

**Neoplasms, Second Primary**: Abnormal growths of tissue that follow a previous neoplasm but are not metastases of the latter. The second neoplasm may have the same or different histological type and can occur in the same or different organs as the previous neoplasm but in all cases arises from an independent oncogenic event. The development of the second neoplasm may or may not be related to the treatment for the previous neoplasm since genetic risk or predisposing factors may actually be the cause.

**Bias (Epidemiology)**: Any deviation of results or inferences from the truth, or processes leading to such deviation. Bias can result from several sources: one-sided or systematic variations in measurement from the true value (systematic error); flaws in study design; deviation of inferences, interpretations, or analyses based on flawed data or data collection; etc. There is no sense of prejudice or subjectivity implied in the assessment of bias under these conditions.

**Peritoneal Dialysis**: Dialysis fluid being introduced into and removed from the peritoneal cavity as either a continuous or an intermittent procedure.

**Peripheral Arterial Disease**: Lack of perfusion in the EXTREMITIES resulting from atherosclerosis. It is characterized by INTERMITTENT CLAUDICATION, and an ANKLE BRACHIAL INDEX of 0.9 or less.

**Germany**

**Colonic Neoplasms**: Tumors or cancer of the COLON.

**Hydroxymethylglutaryl-CoA Reductase Inhibitors**: Compounds that inhibit HMG-CoA reductases. They have been shown to directly lower cholesterol synthesis.

**Graft Survival**: The survival of a graft in a host, the factors responsible for the survival and the changes occurring within the graft during growth in the host.

**Postoperative Complications**: Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.

**Educational Status**: Educational attainment or level of education of individuals.

**Fractures, Bone**: Breaks in bones.

**Occupational Exposure**: The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.

**Occupational Diseases**: Diseases caused by factors involved in one's employment.

**Kidney Transplantation**: The transference of a kidney from one human or animal to another.

**British Columbia**: A province of Canada on the Pacific coast. Its capital is Victoria. The name given in 1858 derives from the Columbia River which was named by the American captain Robert Gray for his ship Columbia which in turn was named for Columbus. (From Webster's New Geographical Dictionary, 1988, p178 & Room, Brewer's Dictionary of Names, 1992, p81-2)

**Norway**

**Kidney Diseases**: Pathological processes of the KIDNEY or its component tissues.

**Asian Continental Ancestry Group**: Individuals whose ancestral origins are in the southeastern and eastern areas of the Asian continent.

**Hawaii**: A group of islands in Polynesia, in the north central Pacific Ocean, comprising eight major and 114 minor islands, largely volcanic and coral. Its capital is Honolulu. It was first reached by Polynesians about 500 A.D. It was discovered and named the Sandwich Islands in 1778 by Captain Cook. The islands were united under the rule of King Kamehameha 1795-1819 and requested annexation to the United States in 1893 when a provisional government was set up. Hawaii was established as a territory in 1900 and admitted as a state in 1959. The name is from the Polynesian Owhyhii, place of the gods, with reference to the two volcanoes Mauna Kea and Mauna Loa, regarded as the abode of the gods. (From Webster's New Geographical Dictionary, 1988, p493 & Room, Brewer's Dictionary of Names, 1992, p2330)

**Adenocarcinoma, Mucinous**: An adenocarcinoma producing mucin in significant amounts. (From Dorland, 27th ed)

**Infant, Newborn**: An infant during the first month after birth.

**Carcinoma**: A malignant neoplasm made up of epithelial cells tending to infiltrate the surrounding tissues and give rise to metastases. It is a histological type of neoplasm but is often wrongly used as a synonym for "cancer." (From Dorland, 27th ed)

**Canada**: The largest country in North America, comprising 10 provinces and three territories. Its capital is Ottawa.

**Morbidity**: The proportion of patients with a particular disease during a given year per given unit of population.

**Karnofsky Performance Status**: A performance measure for rating the ability of a person to perform usual activities, evaluating a patient's progress after a therapeutic procedure, and determining a patient's suitability for therapy. It is used most commonly in the prognosis of cancer therapy, usually after chemotherapy and customarily administered before and after therapy. It was named for Dr. David A. Karnofsky, an American specialist in cancer chemotherapy.

**Viral Load**: The quantity of measurable virus in a body fluid. Change in viral load, measured in plasma, is sometimes used as a SURROGATE MARKER in disease progression.

**Neoplasms, Glandular and Epithelial**: Neoplasms composed of glandular tissue, an aggregation of epithelial cells that elaborate secretions, and of any type of epithelium itself. The concept does not refer to neoplasms located in the various glands or in epithelial tissue.

**Nurses**: Professionals qualified by graduation from an accredited school of nursing and by passage of a national licensing examination to practice nursing. They provide services to patients requiring assistance in recovering or maintaining their physical or mental health.

**Continental Population Groups**: Groups of individuals whose putative ancestry is from native continental populations based on similarities in physical appearance.

**Melanoma**: A malignant neoplasm derived from cells that are capable of forming melanin, which may occur in the skin of any part of the body, in the eye, or, rarely, in the mucous membranes of the genitalia, anus, oral cavity, or other sites. It occurs mostly in adults and may originate de novo or from a pigmented nevus or malignant lentigo. Melanomas frequently metastasize widely, and the regional lymph nodes, liver, lungs, and brain are likely to be involved. The incidence of malignant skin melanomas is rising rapidly in all parts of the world. (Stedman, 25th ed; from Rook et al., Textbook of Dermatology, 4th ed, p2445)

**Osteoporotic Fractures**: Breaks in bones resulting from low bone mass and microarchitectural deterioration characteristic of OSTEOPOROSIS.

**Reoperation**: A repeat operation for the same condition in the same patient due to disease progression or recurrence, or as followup to failed previous surgery.

**Computer Simulation**: Computer-based representation of physical systems and phenomena such as chemical processes.

## Microvascular loops and networks as prognostic indicators in choroidal and ciliary body melanomas. (1/14874)

BACKGROUND: Malignant melanoma of the ciliary body and choroid of the eye is a tumor that disseminates frequently, and 50% of the diagnosed patients die within 10 years. We investigated the hypothesis that, by histopathologic analysis of the arrangement of microvessels (i.e., small blood vessels) in loops and networks, we might be able to differentiate better those patients with a favorable prognosis from those with a poor prognosis. METHODS: We conducted a population-based, retrospective cohort study of melanoma-specific and all-cause mortality for 167 consecutive patients who had an eye surgically removed because of malignant choroidal or ciliary body melanoma during the period from 1972 through 1981. Microvascular loops and networks were evaluated independently by two pathologists who were unaware of patient outcome. RESULTS: Microvascular patterns could be assessed in 134 (80%) of 167 melanoma specimens. The 10-year probability of melanoma-specific survival was worse if microvascular loops (0.45 versus 0.83; two-sided P<.0001) and networks (0.41 versus 0.72, two-sided P<.0001) were present. In multivariate Cox regression analysis of melanoma-specific survival, the hazard ratios were 1.66 (95% confidence interval [CI] = 1.19-2.30) for the presence of loops and networks as a combined three-category variable, 2.36 (95% CI = 1.37-4.05) for the presence of epithelioid cells, 1.11 (95% CI = 1.03-1.19) for the largest basal tumor diameter (evaluated as a continuous variable), and 2.14 (95% CI = 1.25-3.67) for ciliary body involvement. CONCLUSIONS: Patients with malignant uveal melanoma who have a favorable prognosis can be distinguished from those with a poor prognosis by histopathologic analysis of microvascular patterns in uveal melanoma tumor specimens. (+info)## Effects of calcium-channel blockade in older patients with diabetes and systolic hypertension. Systolic Hypertension in Europe Trial Investigators. (2/14874)

BACKGROUND: Recent reports suggest that calcium-channel blockers may be harmful in patients with diabetes and hypertension. We previously reported that antihypertensive treatment with the calcium-channel blocker nitrendipine reduced the risk of cardiovascular events. In this post hoc analysis, we compared the outcome of treatment with nitrendipine in diabetic and nondiabetic patients. METHODS: After stratification according to center, sex, and presence or absence of previous cardiovascular complications, 4695 patients (age, > or =60 years) with systolic blood pressure of 160 to 219 mm Hg and diastolic pressure below 95 mm Hg were randomly assigned to receive active treatment or placebo. Active treatment consisted of nitrendipine (10 to 40 mg per day) with the possible addition or substitution of enalapril (5 to 20 mg per day) or hydrochlorothiazide (12.5 to 25 mg per day) or both, titrated to reduce the systolic blood pressure by at least 20 mm Hg and to less than 150 mm Hg. In the control group, matching placebo tablets were administered similarly. RESULTS: At randomization, 492 patients (10.5 percent) had diabetes. After a median follow-up of two years, the systolic and diastolic blood pressures in the placebo and active-treatment groups differed by 8.6 and 3.9 mm Hg, respectively, among the diabetic patients. Among the 4203 patients without diabetes, systolic and diastolic pressures differed by 10.3 and 4.5 mm Hg, respectively, in the two groups. After adjustment for possible confounders, active treatment was found to have reduced overall mortality by 55 percent (from 45.1 deaths per 1000 patients to 26.4 deaths per 1000 patients), mortality from cardiovascular disease by 76 percent, all cardiovascular events combined by 69 percent, fatal and nonfatal strokes by 73 percent, and all cardiac events combined by 63 percent in the group of patients with diabetes. Among the nondiabetic patients, active treatment decreased all cardiovascular events combined by 26 percent and fatal and nonfatal strokes by 38 percent. In the group of patients receiving active treatment, reductions in overall mortality, mortality from cardiovascular disease, and all cardiovascular events were significantly larger among the diabetic patients than among the nondiabetic patients (P=0.04, P=0.02, and P=0.01, respectively). CONCLUSIONS: Nitrendipine-based antihypertensive therapy is particularly beneficial in older patients with diabetes and isolated systolic hypertension. Thus, our findings do not support the hypothesis that the use of long-acting calcium-channel blockers may be harmful in diabetic patients. (+info)## Association between age and survival following major amputation. The Scottish Vascular Audit Group. (3/14874)

OBJECTIVES: To determine whether age is associated with survival following major amputation and whether this association is independent or simply reflects selection bias in amputation level. DESIGN AND MATERIALS: Computer linkage of routine discharge and death data on the 2759 patients undergoing major amputation in Scotland between 1989 and 1993 for peripheral arterial disease. METHODS: Cox's proportional hazards model and multivariate logistic regression analysis using death as the outcome variable and age, sex, urgency, amputation level and recent arterial reconstructive surgery as predictor variables. RESULTS: Proximal amputation was more common in older patients. Survival was associated with both age (p < 0.001) and amputation level (p < 0.001). Age was an independent predictor of death at 30 days (p < 0.0001), 6 months (p < 0.001), 12 months (p < 0.0001) and 2 years (p < 0.0001) postoperation. CONCLUSIONS: Survival following amputation was poor, with only half the patients alive at 2 years. Above-knee amputation was associated with poorer survival, presumably due to the presence of more severe and widespread disease, and was undertaken more commonly in older patients. However, age remained a predictor of survival after adjustment for amputation level. Higher early mortality suggest that a worse prognosis in elderly patients cannot be attributed wholly to actuarial considerations. (+info)## Prognostic value of ECG findings for total, cardiovascular disease, and coronary heart disease death in men and women. (4/14874)

OBJECTIVE: To study abnormalities in the resting ECG as independent predictors for all cause, cardiovascular disease (CVD), and coronary heart disease (CHD) mortality in a population based random sample of men and women, and to explore whether their prognostic value is different between sexes. DESIGN AND SUBJECTS: An age and sex stratified random sample was selected from the total Belgian population aged 25 to 74 years. Baseline data were gathered and resting ECGs were classified according to Minnesota code criteria. The sample was then followed for at least 10 years with respect to cause specific death. Results are based on observations from 5208 men and 4746 women free from prevalent CHD at the start of the follow up period. RESULTS: Although the prevalence of major abnormalities in general was comparable between sexes, women had more ischaemic findings, ST segment changes, and abnormal T waves on their baseline ECG, while men showed more arrhythmias, bundle branch blocks, and left ventricular hypertrophy. Fitting the multiplicative effect on subsequent mortality between all ECG classifications under study and sex indicated that the prognostic value of ECG changes was equal in women and men. Independently of other risk factors and other major ECG changes, almost all ECG classifications were significantly related to all cause, CVD, and CHD mortality. The most predictive ECG findings for CVD death were ST segment depression (risk ratio (RR) 4.71), major ECG findings (RR 3.26), left ventricular hypertrophy (RR 2.79), bundle branch blocks (RR 2.58), T wave flattening (RR 2.47), ischaemic ECG findings (RR 2.35), and arrhythmias (RR 2.15). The prognostic value of major ECG findings for CVD and CHD death was more powerful than well established cardiovascular risk factors. CONCLUSIONS: Abnormalities in the baseline ECG are strongly associated with subsequent all cause, CVD, and CHD mortality. Their predictive value was similar for men and women. (+info)## Recurrence in affective disorder: analyses with frailty models. (5/14874)

The risk of recurrence in affective disorder is influenced by the number of prior episodes and by a person's tendency toward recurrence. Newly developed frailty models were used to estimate the effect of the number of episodes on the rate of recurrence, taking into account individual frailty toward recurrence. The study base was the Danish psychiatric case register of all hospital admissions for primary affective disorder in Denmark during 1971-1993. A total of 20,350 first-admission patients were discharged with a diagnosis of major affective disorder. For women with unipolar disorder and for all kinds of patients with bipolar disorder, the rate of recurrence was affected by the number of prior episodes even when the effect was adjusted for individual frailty toward recurrence. No effect of episodes but a large effect of the frailty parameter was found for unipolar men. The authors concluded that the risk of recurrence seems to increase with the number of episodes of bipolar affective disorder in general and for women with unipolar disorder. (+info)## Influence of a family history of cancer within and across multiple sites on patterns of cancer mortality risk for women. (6/14874)

A case-control study nested within a large cohort, the American Cancer Society Cancer Prevention Study-1, was conducted to test associations between a family history of cancer and cancer mortality in women. By using logistic regression, the authors analyzed family history, as reported by 429,483 women enrolled in 1959, relative to subsequent mortality through 1972 from cancer within and across multiple sites. The associations between family history and cancer mortality were generally stronger within cancer sites than across cancer sites. Within-site associations were found for breast cancer (odds ratio (OR) = 1.9), colorectal cancer (OR = 1.6), stomach cancer (OR = 1.9), and lung cancer (OR = 1.7). Across-site associations were observed for a family history of 1) breast cancer as a risk factor for ovarian cancer mortality (OR = 1.6), 2) stomach cancer as a risk factor for ovarian cancer mortality (OR = 1.5), and 3) uterine cancer as a risk factor for pancreatic cancer mortality (OR = 1.6). A general pattern of positive associations was observed between a family history of cancer at several sites and subsequent death from pancreatic cancer. These findings support the growing body of evidence from cancer genetics suggesting that inherited cancer-susceptibility genes increase the risk for cancer at many sites and are not specific to cancer risk within a single site. (+info)## Prognostic significance of extent of disease in bone in patients with androgen-independent prostate cancer. (7/14874)

PURPOSE: To evaluate the prognostic significance of a bone scan index (BSI) based on the weighted proportion of tumor involvement in individual bones, in relation to other factors and to survival in patients with androgen-independent prostate cancer. PATIENTS AND METHODS: Baseline radionuclide bone scans were reviewed in 191 assessable patients with androgen-independent disease who were enrolled onto an open, randomized trial of liarozole versus prednisone. The extent of skeletal involvement was assessed by scoring each scan using the BSI and independently according to the number of metastatic lesions. The relationship of the scored bone involvement to other known prognostic factors was explored in single- and multiple-variable analyses. RESULTS: In single-variable analyses, the pretreatment factors found to be associated with survival were age (P = .0446), performance status (P = .0005), baseline prostate-specific antigen (P = .0001), hemoglobin (P = .0001), alkaline phosphatase (P = .0002), AST (P = .0021), lactate dehydrogenase (P = .0001), and treatment (P = .0098). The extent of osseous disease was significant using both the BSI (P = .0001) and the number of lesions present (P = .0001). In multiple-variable proportional hazards analyses, only BSI, age, hemoglobin, lactate dehydrogenase, and treatment arm were associated with survival. When the patient population was divided into three equal groups, with BSI values of < 1.4%, 1.4% to 5.1%, and > 5.1%, median survivals of 18.3, 15.5, and 8.1 months, respectively, were observed (P = .0079). CONCLUSION: The BSI quantifies the extent of skeletal involvement by tumor. It allows the identification of patients with distinct prognoses for stratification in clinical trials. Further study is needed to assess the utility of serial BSI determinations in monitoring treatment effects. The BSI may be particularly useful in the evaluation of agents for which prostate-specific antigen changes do not reflect clinical outcomes accurately. (+info)## Hematocrit level and associated mortality in hemodialysis patients. (8/14874)

Although a number of clinical studies have shown that increased hematocrits are associated with improved outcomes in terms of cognitive function, reduced left ventricular hypertrophy, increased exercise tolerance, and improved quality of life, the optimal hematocrit level associated with survival has yet to be determined. The association between hematocrit levels and patient mortality was retrospectively studied in a prevalent Medicare hemodialysis cohort on a national scale. All patients survived a 6-mo entry period during which their hematocrit levels were assessed, from July 1 through December 31, 1993, with follow-up from January 1 through December 31, 1994. Patient comorbid conditions relative to clinical events and severity of disease were determined from Medicare claims data and correlated with the entry period hematocrit level. After adjusting for medical diseases, our results showed that patients with hematocrit levels less than 30% had significantly higher risk of all-cause (12 to 33%) and cause-specific death, compared to patients with hematocrits in the 30% to less than 33% range. Without severity of disease adjustment, patients with hematocrit levels of 33% to less than 36% appear to have the lowest risk for all-cause and cardiac mortality. After adjusting for severity of disease, the impact of hematocrit levels of 33% to less than 36% is vulnerable to the patient sample size but also demonstrates a further 4% reduced risk of death. Overall, these findings suggest that sustained increases in hematocrit levels are associated with improved patient survival. (+info)###### survival - Interval censored Cox proportional hazards model in R - Cross Validated

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Regression modelsKaplan-MeierCox'sWeibullExponentialEstimatesSemi-parametricEstimateLikelihoodWeightsMultivariateEstimationAssumption holdsSemiparametric proportionalRisk factorsDataNonparametricLogisticExplanatory variablesCovariateBaseline hazard rateMethodsLogarithm of the hazardLikelihoodBootstrapStatisticalAdditiveEpidemiologyTime dependentTreatment effect in randomizedCoxphPiecewiseProportionalityPredictiveExponential distributionVersusPrognosisIncidenceCoefficientsSurvival timesEstimator2019SubsetParametersProbabilityExtensions

###### Regression models2

- Likelihood based regression models, such as the normal linear regression model and the linear logistic model, assume a linear (or some other parametric) form for the covariate effects. (psu.edu)
- This course will also explore semi-parametric models such as the Cox proportional hazards regression models and parametric models inlcuding exponential, Weibull and log-logistic regression model. (luc.edu)

###### Kaplan-Meier1

- Concepts, models and techniques in survival analysis including types of censoring and truncation, Kaplan-Meier estimators, log-rank statistics, parametric models, proportional hazards models, extended PH models, competing risks, recurrent events and frailty models. (utoronto.ca)

###### Cox's1

- Local Scoring can also be applied to non-standard models like Cox's proportional hazards model for survival data. (psu.edu)

###### Weibull1

- Likewise, if a baseline Weibull distribution aft model is used, the parameter estimates are just a linear transformation of those used in the proportional hazards model with Weibull baseline distribution. (stackexchange.com)

###### Exponential1

- In the case of the exponential distribution, the proportional hazards and aft model are equivalent, so if distribution is set to exponential, this is a proportional hazards model with an exponential baseline. (stackexchange.com)

###### Estimates1

###### Semi-parametric1

- If a semi-parametric model is desired, as found implemented in intcox, a word of caution: there are several issues with the current version of intcox (algorithm typically prematurely terminates significantly far from the MLE, fails outright with uncensored observations, no standard errors automatically presented). (stackexchange.com)

###### Estimate1

###### Likelihood1

- The technique is applicable to any likelihood-based regression model: the class of Generalized Linear Models contains many of these. (psu.edu)

###### Weights1

- The authors propose a two-stage inverse-probability-of-selection weighted proportional hazards model, using weights estimated from auxiliary information on the sampling process. (ssc.ca)

###### Multivariate4

- Estimation of multivariate frailty models using penalized partial likelihood. (deepdyve.com)
- In labor and population economics, the Mixed Proportional Hazard (MPH) model and its multivariate extensions, the so-called Multivariate Mixed Proportional Hazard (MMPH) models, are state of the art and the most widely used models to estimate durations and their determinants. (uni-tuebingen.de)
- Determinants of infant and child mortality in Zimbabwe: Results of multivariate hazard analysis ," Demographic Research , Max Planck Institute for Demographic Research, Rostock, Germany, vol. 21(13), pages 367-384, October. (repec.org)
- The effects of treatment were examined using a multivariate Cox proportional hazards model and Kaplan-Meier survival analysis. (medscape.com)

###### Estimation20

- A counting process approach to maximum likelihood estimation in frailty models. (deepdyve.com)
- Two-stage residual inclusion estimation: addressing endogeneity in health econometric modeling. (deepdyve.com)
- The random herd-year and sire effects were later included in the model for the estimation of sire and herd-year variance components. (sun.ac.za)
- In paper, we propose a novel Gaussian quadrature estimation method in various frailty proportional hazards models. (northwestern.edu)
- Liu, L & Huang, X 2008, ' The use of Gaussian quadrature for estimation in frailty proportional hazards models ', Statistics in Medicine , vol. 27, no. 14, pp. 2665-2683. (northwestern.edu)
- In my presentation I will describe the stochastic gradient descent algorithm that was applied in the log- likelihood estimation process of coefficients' calcualtions of the Cox proportional hazards model. (sthda.com)
- Adaptive Penalized Weighted Least Absolute Deviations Estimation for the Accelerated Failure Time Model. (wroc.pl)
- We consider the estimation of the semiparametric proportional hazards model with an unspecified baseline hazard function where the effect of a continuous covariate is assumed to be monotone. (elsevier.com)
- Previous work on nonparametric maximum likelihood estimation for isotonic proportional hazard regression with right-censored data is computationally intensive, lacks theoretical justification, and may be prohibitive in large samples. (elsevier.com)
- Fine, Jason P. / Partial likelihood estimation of isotonic proportional hazards models . (elsevier.com)
- In particular, MMPH models allow for the estimation of several durations per individual. (uni-tuebingen.de)
- Marafa Haliru Muhammad, Usman Umar, Estimation of Population Based Colorectal Cancer Survival Analysis Using Cox Proportional Hazards Model, Biomedical Statistics and Informatics . (bsijournal.org)
- Non-parametric estimation of the survival and cumulative hazard functions. (york.ac.uk)
- It includes imputation methods for dealing with missing data effectively, methods for dealing with nonlinear relationships and for making the estimation of transformations a formal part of the modeling process, methods for dealing with "too many variables to analyze and not enough observations," and powerful model validation techniques based on the bootstrap. (springer.com)
- It starts with the tests of hypotheses and moves on to regression modeling, time-to-event analysis, density estimation, and resampling methods. (routledge.com)
- The objective of this study is to investigate the problem of goodness of fit testing based on nonparametric function estimation techniques for the random censorship model. (koreascience.or.kr)
- Math Nauk 1987 no.3 Estimation of Probability Density and the Hazard Rate Function in the Koziol-Green Model of Random Censorship Abdushukurov, A.A. (koreascience.or.kr)
- Statistics v.19 Maximum Likelihood Estimation of a survival Function under the Koziol-Green Proportional hazards model of random censorship Cheng, P.E.;Lin, G.D. (koreascience.or.kr)
- Statistics v.19 Estimation in the proportional hazards model of random censorship Csorgo, S. (koreascience.or.kr)
- This text employs numerous actual examples to illustrate survival curve estimation, comparison of survivals of different groups, proper accounting for censoring and truncation, model variable selection, and residual analysis. (indigo.ca)

###### Assumption holds1

- Sir David Cox observed that if the proportional hazards assumption holds (or, is assumed to hold) then it is possible to estimate the effect parameter(s) without any consideration of the hazard function. (wikipedia.org)

###### Semiparametric proportional1

- We use a semiparametric proportional hazard model which is augmented by an ARMA structure very similar to the wide spread ACD model to obtain consistent estimates of the baseline survivor function and to capture well known serial dependencies in the trade intensity process. (uni-konstanz.de)

###### Risk factors4

- In the MSM model, the weight was based on measurements of established cardiovascular risk factors and co-morbidity. (eur.nl)
- Furthermore, the Cox regression model extends survival analysis methods to assess simultaneously the effect of several risk factors on survival time. (sthda.com)
- Use proportional hazards regression techniques to make inferences about the possible relationship between survival time and potential risk factors. (york.ac.uk)
- The present study was conducted to apply the semi-parametric Cox PH model and use parametric proportional hazards (PH) and accelerated failure time (AFT) models to identify the risk factors related to survival of TM patients. (ac.ir)

###### Data42

- In: Jewell N.P., Kimber A.C., Lee ML.T., Whitmore G.A. (eds) Lifetime Data: Models in Reliability and Survival Analysis. (springer.com)
- To actually run the model, you will need to enter the data into a hazard model regression calculator, which can be found online . (metafilter.com)
- This approach to survival data is called application of the Cox proportional hazards model , sometimes abbreviated to Cox model or to proportional hazards emodel . (wikipedia.org)
- a missing-data filter function, applied to the model.frame, after any subset argument has been used. (psu.edu)
- The Cox proportional hazards model 92 is the most popular model for the analysis of survival data. (springer.com)
- A key element in any statistical simulation is the existence of an appropriate data-generating process: one must be able to simulate data from a specified statistical model. (ices.on.ca)
- While proportional hazard models are a key instrument for survival analysis within the last centuries, the assumption of hazard proportionality might be overly restrictive and their applicability to complex data remains difficult. (springer.com)
- The model is evaluated on multiple datasets, including metastatic colorectal cancer computed tomography imaging data, and significantly reduces the average prediction error compared to the Cox proportional hazards model. (springer.com)
- Background: The appropriate handling of missing covariate data in prognostic modelling studies is yet to be conclusively determined. (ebscohost.com)
- A resampling study was performed to investigate the effects of different missing data methods on the performance of a prognostic model. (ebscohost.com)
- Frailty models for survival data. (deepdyve.com)
- When studying the causal effect of drug use in observational data, marginal structural modeling (MSM) can be used to adjust for time-dependent confounders that are affected by previous treatment. (eur.nl)
- What I have done so far: used 9 months of data to fit the model and 3 remaining months as a holdout validation set. (stackexchange.com)
- This simulation selects a survival time with replacement from the data and then assigns a covariate according to the model of proportional hazards. (umn.edu)
- From an inspection of conditional transaction probabilities based on Bund future transaction data of the DTB we find a decreasing hazard shape providing evidence for the use of non-trading intervals as an indication for the absence of price information among market participants. (uni-konstanz.de)
- We first apply our method to simple frailty models for correlated survival data (e.g. recurrent or clustered failure times), then to joint frailty models for correlated failure times with informative dropout or a dependent terminal event such as death. (northwestern.edu)
- We apply our method to three real data examples: (1) the time to blindness of both eyes in a diabetic retinopathy study, (2) the joint analysis of recurrent opportunistic diseases in the presence of death for HIV-infected patients, and (3) the joint modeling of local, distant tumor recurrences and patients survival in a soft tissue sarcoma study. (northwestern.edu)
- The cox proportional-hazards model is one of the most important methods used for modelling survival analysis data. (sthda.com)
- The results of the different models were finally compared for estimating the effects of correlated aspects of occupational exposure to asbestos on the risk of mesothelioma, using population-based case-control data. (biomedcentral.com)
- The weights proposed in the WC model are therefore time-dependent and estimated from data of the source population. (biomedcentral.com)
- The Cox PH model, because it is built on top of a nonparametric baseline hazard rate, cannot extrapolate to loan ages that are not observed in the data set. (mathworks.com)
- The logistic model treats the age of the loan as a continuous variable, and, therefore, it can extrapolate to predict PDs for ages not observed in the data set. (mathworks.com)
- If, for a particular age, the PD is small and there are no observed defaults in the data, the Cox PH model predicts the PD as zero. (mathworks.com)
- May, M. Royston, P. Egger, M. Justice, A. C. and Sterne, J.A.C. (2004) Development and Validation of Prognosis Model for Survival Time Data: Application to Prognosis of HIV Positive Patients Treated with Anti-retroviral Therapy. (sciencepublishinggroup.com)
- The Cox proportional hazards (PH) model is frequently used to model survival data or time-to-event data, particularly in the presence of censored survival times [ 1 ]. (hindawi.com)
- The aim of this study is to estimate the population based colorectal cancer survival analysis using cox Proportional Hazards model, in order to fits colorectal cancer data in population-based research. (bsijournal.org)
- Also the results show that the data met Cox Proportional Hazards Assumptions. (bsijournal.org)
- Applied Survival Analysis: Regression Modeling of Time- to- Event Data. (bsijournal.org)
- Instead of presenting isolated techniques, this text emphasizes problem solving strategies that address the many issues arising when developing multivariable models using real data and not standard textbook examples. (springer.com)
- Working through the case studies in the book will demonstrate what can be achieved with a little imagination, when modelling complex and challenging data sets. (springer.com)
- Hello, I am a statistician with 2+ years of experience in statistical modeling, data mining, survival analysis, and data visualization on data to derive predictive business insight. (freelancer.com)
- Hi, I have strong statistical background and I have an experince in statistical modelling , analysis and handling data. (freelancer.com)
- Applied Survival Analysis, Second Edition provides a comprehensive and up-to-date introduction to regression modeling for time-to-event data in medical, epidemiological, biostatistical, and other health-related research. (worldcat.org)
- This book fills this gap, providing a comprehensive, self-contained introduction to regression modeling used in the analysis of time-to-event data in epidemiological, biostatistical, and other health-related research. (worldcat.org)
- Most prediction models are developed using a regression model, such as linear regression for continuous outcomes (eg, pain score), logistic regression for binary outcomes (eg, presence or absence of pre-eclampsia), or proportional hazards regression models for time-to-event data (eg, recurrence of venous thromboembolism). (bmj.com)
- The concept of censored data is discussed, and the proportional hazards model is introduced. (xula.edu)
- The proportional hazards model has been developed by Cox (1972) in order to treat continuous time survival data. (xlstat.com)
- Statisticians call this problem censoring , a problem that surfaces when you try to model a time-to-event response measure using data captured over a limited time period. (informit.com)
- Thus, it is often informative to examine the hazard function when time to response data is being analyzed. (pjsor.com)
- In this study Cox proportional hazard model is fitted to patient data of Acute Myeloid Leukemia. (pjsor.com)
- Journal of the American Statistical Association v.74 Nonparametric Statistics Data Modeling Parazen, E. (koreascience.or.kr)
- The course also introduces and explains the concept of modelling survival data based on the widely-use Cox regression model. (jiscmail.ac.uk)

###### Nonparametric3

- The Cox PH model has a nonparametric baseline hazard rate that can match patterns in the PDs much more closely than the fully parametric logistic model. (mathworks.com)
- The book covers, very completely, the nuances of regression modeling with particular emphasis on binary and ordinal logistic regression and parametric and nonparametric survival analysis. (springer.com)
- It then discusses smoothing techniques (loess and thin-plate splines) for classical nonparametric regression as well as binary logistic and Poisson models. (routledge.com)

###### Logistic6

- The exact method computes the exact partial likelihood, which is equivalent to a conditional logistic model. (psu.edu)
- begingroup$ @seanv507 Yes, I'm very new to Survival analysis as explained, I'm even considering doing a Logistic Regression for each period, but I also would like to learn more about Survival models. (stackexchange.com)
- The objectives of the present study were to investigate through simulations a new variance estimator and to compare the estimates from the WC model and standard logistic regression for estimating the effects of correlated temporal aspects of exposure with detailed information on exposure history. (biomedcentral.com)
- The performances of the WC model using the two variance estimators were compared to standard logistic regression. (biomedcentral.com)
- In contrast, the logistic model always gives nonzero probabilities. (mathworks.com)
- In linear and logistic regression models, the ridge regression estimator has been applied as an alternative to the maximum likelihood estimator in the presence of collinearity. (cdc.gov)

###### Explanatory variables7

- We present a bootstrap resampling plan for the Cox partial likelihood estimator for proportional hazards models with nonrandom explanatory variables. (springer.com)
- This expression gives the hazard function at time t for subject i with covariate vector (explanatory variables) X i . (wikipedia.org)
- In an alternative group of models, the explanatory variables act multiplicatively straight on the failure time. (statshelponline.com)
- In occupational settings, it is common to have an occupational exposure as one of the explanatory variables in the model and the association between the outcome and this exposure is of interest. (hindawi.com)
- A Cox model is a well-recognized statistical technique for exploring the relationship between the survival of a patient and several explanatory variables. (xlstat.com)
- A Cox model provides an estimate of the treatment effect on survival after adjustment for other explanatory variables. (xlstat.com)
- The natural log of the hazard function is the response and two of the explanatory variables age and cellularity level of the patient. (pjsor.com)

###### Covariate2

- In a proportional hazards model, the unique effect of a unit increase in a covariate is multiplicative with respect to the hazard rate . (wikipedia.org)
- Effects of covariate omission and categorization when analysing randomized trials with the Cox model. (deepdyve.com)

###### Baseline hazard rate1

- CPH models the underlying hazard rate (for example, risk of death) as a function of a baseline hazard rate and the incremental effects of predictor variables. (informit.com)

###### Methods9

- We develop methods for comparative APC analysis of two independent cause-specific hazard rates assuming that an APC model holds for each one. (nih.gov)
- One of the most popular regression methods for survival analysis is Cox proportional hazards regression, which is utilized to relate a number of threat elements or direct exposures, thought about concurrently, to survival time. (statshelponline.com)
- Statistical Methods in Credit Risk Modelling, University of Michigan, 3 4-27. (sciencepublishinggroup.com)
- Truncated power basis expansions and penalized spline methods are demonstrated for estimating nonlinear exposure-response relationships in the Cox proportional hazards model. (hindawi.com)
- Methods for modeling nonlinearities are needed in those situations when a linear exposure-response is not expected or when one desires to formally assess a nonlinear association. (hindawi.com)
- Many different types of models and methods are discussed. (springer.com)
- Since publication of the first edition nearly a decade ago, analyses using time-to-event methods have increased considerably in all areas of scientific inquiry, mainly as a result of model-building methods available in modern statistical software packages. (worldcat.org)
- The reply to Frost & Thompson by Longford (2001) refers the reader to other methods, expanding the regression model to acknowledge the variability in the x variable, so that no bias arises. (wikipedia.org)
- In general, methods for the structural model require some estimate of the variability of the x variable. (wikipedia.org)

###### Logarithm of the hazard1

- The Cox model can be written as a multiple linear regression of the logarithm of the hazard on the variables \(x_i\) , with the baseline hazard being an 'intercept' term that varies with time. (sthda.com)

###### Likelihood3

- The Cox partial likelihood, shown below, is obtained by using Breslow's estimate of the baseline hazard function, plugging it into the full likelihood and then observing that the result is a product of two factors. (wikipedia.org)
- The iterative convex minorant algorithm which uses pool-adjacent-violators techniques has also been shown to perform well in related parametric likelihood set-ups, but evidences computational difficulties under the proportional hazards model. (elsevier.com)
- To estimate the β parameters of the model (the coefficients of the linear function), we try to maximize the partial likelihood function. (xlstat.com)

###### Bootstrap3

- Bootstrap Applications in Proportional Hazards Models , Ph.D. Dissertation, Iowa State University. (springer.com)
- Loughin T.M., Koehler K.J. (1996) A Semiparametric Bootstrap for Proportional Hazards Models. (springer.com)
- package makes this easy, and it can use the bootstrap to correct for overfitting if you are honest about including all candidate variables in the model. (stackexchange.com)

###### Statistical9

- In statistics and regression analysis , proportional hazards models are "statistical models used in survival analysis that assert that the effect of the study factors on the hazard rate in the study population is multiplicative and does not change over time. (citizendium.org)
- Healthcare informatics research is a scientific endeavor that applies information science, computer technology, and statistical modeling techniques to develop decision support systems for improving both health service organizations' performance and patient care outcomes. (ebscohost.com)
- However, both the sign and the statistical significance of our model are retained in the CDS spread regressions. (mdpi.com)
- The Cox proportional-hazards model (Cox, 1972) is essentially a regression model commonly used statistical in medical research for investigating the association between the survival time of patients and one or more predictor variables. (sthda.com)
- Statistical model is a frequently used tool that allows to analyze survival with respect to several factors simultaneously. (sthda.com)
- Additionally, statistical model provides the effect size for each factor. (sthda.com)
- Statistical Models Based on Counting Process. (sciencepublishinggroup.com)
- 1999) Variation over Time of the Effects of Prognostic Factors in a Population based Study of Colon Cancer: Comparison of Statistical Models. (bsijournal.org)
- Participants will be assumed to have some knowledge of elementary statistical techniques (e.g. hypothesis testing, standard errors and confidence intervals) and linear regression (e.g. concept of a statistical model, comparing models). (jiscmail.ac.uk)

###### Additive2

- a) complete case analysis (CC) b) single imputation using regression switching with predictive mean matching (SI), c) multiple imputation using regression switching imputation, d) multiple imputation using regression switching with predictive mean matching (MICE-PMM) and e) multiple imputation using flexible additive imputation models. (ebscohost.com)
- Instrumental variable additive hazards models. (deepdyve.com)

###### Epidemiology1

- Age-period-cohort (APC) analysis is widely used in cancer epidemiology to model trends in cancer rates. (nih.gov)

###### Time dependent5

- The proportional hazards model included time-dependent effects of herd-year-season contemporary group and parity by stage of lactation interaction, as well as time-independent effects of sire and age at first calving. (pubfacts.com)
- The fixed effects model comprised of the time-independent effect of age at first calving, the combined time-dependent effects of region x year of calving, number of lactations x within-herd milk production class, year of calving x within-herd protein and year of calving x fat percentage production class. (sun.ac.za)
- Model also had the combined time-dependent effect of herd size x annual herd size change. (sun.ac.za)
- A weighted Cox (WC) model has been proposed to estimate the effects of time-dependent exposures. (biomedcentral.com)
- Different models with selected time-dependent aspects of exposure such as intensity, duration, and time since cessation were considered. (biomedcentral.com)

###### Treatment effect in randomized1

- The use of restricted mean survival time to estimate the treatment effect in randomized clinical trials when the proportional hazards assumption is in doubt. (semanticscholar.org)

###### Coxph1

- Displays diagnostics graphs presenting goodness of Cox Proportional Hazards Model fit, that can be calculated with coxph function. (datanovia.com)

###### Piecewise2

- We approximate the unspecified baseline hazard by a piecewise constant one, resulting in a parametric model that can be fitted conveniently by Gaussian quadrature tools in standard software such as SAS Proc NLMIXED. (northwestern.edu)
- I need an expert in R who knows cox proportional hazard model to help fit a piecewise exponential baseline hazard. (freelancer.com)

###### Proportionality1

- We propose a deep model for computed-tomography-based survival analysis providing a hazard probability output representation comparable to Cox regression without relying on the hazard proportionality assumption. (springer.com)

###### Predictive3

- Campbell, Hilscher and Szilagyi [ 2 ] concluded that the strong predictive power of the Merton DD model came from the functional form imposed by the Merton model. (mdpi.com)
- in predictive modelling applications, correction is neither necessary nor appropriate. (wikipedia.org)
- In predictive modelling, no. (wikipedia.org)

###### Exponential distribution1

- In the case of the exponential distribution, the proportional hazards and aft model are equivalent, so if distribution is set to exponential, this is a proportional hazards model with an exponential baseline. (stackexchange.com)

###### Versus1

- Dyana Kwamboka Mageto, Samuel Musili Mwalili, Anthony Gichuhi Waititu, Modelling of Credit Risk: Random Forests versus Cox Proportional Hazard Regression, American Journal of Theoretical and Applied Statistics . (sciencepublishinggroup.com)

###### Prognosis1

###### Incidence2

- The purpose of this study was to assess the relationship between the psychosocial concepts of the demand-control model and the incidence of shoulder symptoms in a working population. (cdc.gov)
- We used Cox proportional hazards regression to estimate the relative incidence rate of diabetes by serostatus, with adjustment for age, sex, education, cardiovascular disease, smoking, and cholesterol levels. (diabetesjournals.org)

###### Coefficients2

- We use these simulation techniques to estimate the bias and variance of regression coefficients and to approximate the significance levels of goodness-of-fit statistics for testing the assumption of the proportional hazards model. (umn.edu)
- Interpreting a Cox model involves examining the coefficients for each explanatory variable. (xlstat.com)

###### Survival times1

- 3.4 Fitting the Proportional Hazards Model with Tied Survival Times. (wiley.com)

###### Estimator3

- The WC model with the superpopulation variance estimator provides an alternative analytical approach for estimating the effects of time-varying exposures with detailed history exposure information in case-control studies, especially if many subjects have time-varying exposure intensity over lifetime, and if only one control is available for each case. (biomedcentral.com)
- A separate estimator of the baseline hazard function is provided. (elsevier.com)
- Wekesa O. (2012), Modelling Credit Risk for Personal Loans Using Product-Limit Estimator. (sciencepublishinggroup.com)

###### 20191

- Anonymous (2019), Proportional hazards model (English). (citizendium.org)

###### Subset1

- Simulation studies show that the proposed procedures are more stable in prediction and more effective in computation than the best subset variable selection, and they reduce model complexity as effectively as the best subset variable selection. (elsevier.com)

###### Parameters2

- When a given proportional hazards model appears adequate, we derive simple expressions for the relative hazards using identifiable APC parameters. (nih.gov)
- Some of the underlying theory is discussed, including Cox regression to estimate parameters of the model. (xula.edu)

###### Probability3

- Hi, I am analyzing the influence of some variables on the probability of failure in the sample of firms using parametric survival model in STATA. (stata.com)
- The Cox proportional hazard model is used to compare the forecasting power of Bharath and Shumway's naive model, which retains the functional form of the Merton DD model and computes the default probability in a naive way, with our new model, which treats investors' ambiguity aversion as additional information. (mdpi.com)
- The hazard function is the probability that an individual will experience an event (for example, death) within a small time interval, given that the individual has survived up to the beginning of the interval. (xlstat.com)

###### Extensions2

- Extensions of the random forest approach to survival analysis provide an alternative way to build a risk prediction model. (sciencepublishinggroup.com)
- This course begins with an overview and continues to cover the following topics: summary statistics and exploratory graphics, simple hypothesis testing, regression modelling using the Cox model and some extensions to this model. (jiscmail.ac.uk)