Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. (Webster, 3d ed)

Financial support of research activities.

A plan for collecting and utilizing data so that desired information can be obtained with sufficient precision or so that an hypothesis can be tested properly.

The moral obligations governing the conduct of research. Used for discussions of research ethics as a general topic.

Those individuals engaged in research.

Research carried out by nurses, generally in clinical settings, in the areas of clinical practice, evaluation, nursing education, nursing administration, and methodology.

The integration of epidemiologic, sociological, economic, and other analytic sciences in the study of health services. Health services research is usually concerned with relationships between need, demand, supply, use, and outcome of health services. The aim of the research is evaluation, particularly in terms of structure, process, output, and outcome. (From Last, Dictionary of Epidemiology, 2d ed)

The application of discoveries generated by laboratory research and preclinical studies to the development of clinical trials and studies in humans. A second area of translational research concerns enhancing the adoption of best practices.

Research into the cause, transmission, amelioration, elimination, or enhancement of inherited disorders and traits.

Research carried out by nurses in the clinical setting and designed to provide information that will help improve patient care. Other professional staff may also participate in the research.

The study of laws, theories, and hypotheses through a systematic examination of pertinent facts and their interpretation in the field of dentistry. (From Jablonski, Illustrated Dictionary of Dentistry, 1982, p674)

Collaborative process of research involving researchers and community representatives.

Research that involves the application of the behavioral and social sciences to the study of the actions or reactions of persons or animals in response to external or internal stimuli. (from American Heritage Dictionary, 4th ed)

Any type of research that employs nonnumeric information to explore individual or group characteristics, producing findings not arrived at by statistical procedures or other quantitative means. (Qualitative Inquiry: A Dictionary of Terms Thousand Oaks, CA: Sage Publications, 1997)

The use of humans as investigational subjects.

Organizations representing specialized fields which are accepted as authoritative; may be non-governmental, university or an independent research organization, e.g., National Academy of Sciences, Brookings Institution, etc.

Voluntary authorization, by a patient or research subject, with full comprehension of the risks involved, for diagnostic or investigative procedures, and for medical and surgical treatment.

The study, based on direct observation, use of statistical records, interviews, or experimental methods, of actual practices or the actual impact of practices or policies.

Experimentation on, or using the organs or tissues from, a human or other mammalian conceptus during the prenatal stage of development that is characterized by rapid morphological changes and the differentiation of basic structures. In humans, this includes the period from the time of fertilization to the end of the eighth week after fertilization.

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.

The interaction of two or more persons or organizations directed toward a common goal which is mutually beneficial. An act or instance of working or acting together for a common purpose or benefit, i.e., joint action. (From Random House Dictionary Unabridged, 2d ed)

Detailed account or statement or formal record of data resulting from empirical inquiry.

Time period from 1901 through 2000 of the common era.

Experimentation on STEM CELLS and on the use of stem cells.

Works about pre-planned studies of the safety, efficacy, or optimum dosage schedule (if appropriate) of one or more diagnostic, therapeutic, or prophylactic drugs, devices, or techniques selected according to predetermined criteria of eligibility and observed for predefined evidence of favorable and unfavorable effects. This concept includes clinical trials conducted both in the U.S. and in other countries.

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.

A group of techniques developed to apply scientific methods and tools to solve the problems of DECISION MAKING in complex organizations and systems. Operations research searches for optimal solutions in situations of conflicting GOALS and makes use of mathematical models from which solutions for actual problems may be derived. (From Psychiatric Dictionary, 6th ed)

"The business or profession of the commercial production and issuance of literature" (Webster's 3d). It includes the publisher, publication processes, editing and editors. Production may be by conventional printing methods or by electronic publishing.

Systematic gathering of data for a particular purpose from various sources, including questionnaires, interviews, observation, existing records, and electronic devices. The process is usually preliminary to statistical analysis of the data.

An agency of the PUBLIC HEALTH SERVICE established in 1990 to "provide indexing, abstracting, translating, publishing, and other services leading to a more effective and timely dissemination of information on research, demonstration projects, and evaluations with respect to health care to public and private entities and individuals engaged in the improvement of health care delivery..." It supersedes the National Center for Health Services Research. The United States Agency for Health Care Policy and Research was renamed Agency for Healthcare Research and Quality (AHRQ) under the Healthcare Research and Quality Act of 1999.

The circulation or wide dispersal of information.

Interaction between research personnel and research subjects.

The use of statistical methods in the analysis of a body of literature to reveal the historical development of subject fields and patterns of authorship, publication, and use. Formerly called statistical bibliography. (from The ALA Glossary of Library and Information Science, 1983)

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.

A publication issued at stated, more or less regular, intervals.

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.

Facilities that collect, store, and distribute tissues, e.g., cell lines, microorganisms, blood, sperm, milk, breast tissue, for use by others. Other uses may include transplantation and comparison of diseased tissues in the identification of cancer.

The use of animals as investigational subjects.

Copies of a work or document distributed to the public by sale, rental, lease, or lending. (From ALA Glossary of Library and Information Science, 1983, p181)

Educational institutions providing facilities for teaching and research and authorized to grant academic degrees.

The interaction of persons or groups of persons representing various nations in the pursuit of a common goal or interest.

Time period from 2001 through 2100 of the common era.

Human experimentation that is not intended to benefit the subjects on whom it is performed. Phase I drug studies (CLINICAL TRIALS, PHASE I AS TOPIC) and research involving healthy volunteers are examples of nontherapeutic human experimentation.

A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.

A systematic statement of policy rules or principles. Guidelines may be developed by government agencies at any level, institutions, professional societies, governing boards, or by convening expert panels. The text may be cursive or in outline form but is generally a comprehensive guide to problems and approaches in any field of activity. For guidelines in the field of health care and clinical medicine, PRACTICE GUIDELINES AS TOPIC is available.

The study of natural phenomena by observation, measurement, and experimentation.

Branch of medicine concerned with the prevention and control of disease and disability, and the promotion of physical and mental health of the population on the international, national, state, or municipal level.

Criteria and standards used for the determination of the appropriateness of the inclusion of patients with specific conditions in proposed treatment plans and the criteria used for the inclusion of subjects in various clinical trials and other research protocols.

Community or individual involvement in the decision-making process.

Decisions, usually developed by government policymakers, for determining present and future objectives pertaining to the health care system.

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.

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.

Communication, in the sense of cross-fertilization of ideas, involving two or more academic disciplines (such as the disciplines that comprise the cross-disciplinary field of bioethics, including the health and biological sciences, the humanities, and the social sciences and law). Also includes problems in communication stemming from differences in patterns of language usage in different academic or medical disciplines.

Conferences, conventions or formal meetings usually attended by delegates representing a special field of interest.

The process of formulating, improving, and expanding educational, managerial, or service-oriented work plans (excluding computer program development).

The form and structure of analytic studies in epidemiologic and clinical research.

A situation in which an individual might benefit personally from official or professional actions. It includes a conflict between a person's private interests and official responsibilities in a position of trust. The term is not restricted to government officials. The concept refers both to actual conflict of interest and the appearance or perception of conflict.

The privacy of information and its protection against unauthorized disclosure.

The interactions between members of a community and representatives of the institutions within that community.

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.

Conversations with an individual or individuals held in order to obtain information about their background and other personal biographical data, their attitudes and opinions, etc. It includes school admission or job interviews.

Elements of limited time intervals, contributing to particular results or situations.

Human experimentation that is intended to benefit the subjects on whom it is performed.

The prediction or projection of the nature of future problems or existing conditions based upon the extrapolation or interpretation of existing scientific data or by the application of scientific methodology.

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.

The profession of writing. Also the identity of the writer as the creator of a literary production.

Intentional falsification of scientific data by presentation of fraudulent or incomplete or uncorroborated findings as scientific fact.

Research carried out by nurses concerning techniques and methods to implement projects and to document information, including methods of interviewing patients, collecting data, and forming inferences. The concept includes exploration of methodological issues such as human subjectivity and human experience.

A course or method of action selected, usually by a government, from among alternatives to guide and determine present and future decisions.

Studies designed to assess the efficacy of programs. They may include the evaluation of cost-effectiveness, the extent to which objectives are met, or impact.

Revealing of information, by oral or written communication.

The process of making a selective intellectual judgment when presented with several complex alternatives consisting of several variables, and usually defining a course of action or an idea.

The interactions between representatives of institutions, agencies, or organizations.

Centers for acquiring, characterizing, and storing organs or tissue for future use.

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

Organizational development including enhancement of management structures, processes and procedures, within organizations and among different organizations and sectors to meet present and future needs.

The decision process by which individuals, groups or institutions establish policies pertaining to plans, programs or procedures.

Preferentially rated health-related activities or functions to be used in establishing health planning goals. This may refer specifically to PL93-641.

Studies in which the presence or absence of disease or other health-related variables are determined in each member of the study population or in a representative sample at one particular time. This contrasts with LONGITUDINAL STUDIES which are followed over a period of time.

Medical complexes consisting of medical school, hospitals, clinics, libraries, administrative facilities, etc.

The science of controlling or modifying those conditions, influences, or forces surrounding man which relate to promoting, establishing, and maintaining health.

Countries in the process of change with economic growth, that is, an increase in production, per capita consumption, and income. The process of economic growth involves better utilization of natural and human resources, which results in a change in the social, political, and economic structures.

The broad dissemination of new ideas, procedures, techniques, materials, and devices and the degree to which these are accepted and used.

The systematic study of the complete DNA sequences (GENOME) of organisms.

Encouraging consumer behaviors most likely to optimize health potentials (physical and psychosocial) through health information, preventive programs, and access to medical care.

Informed consent given by a parent on behalf of a minor or otherwise incompetent child.

The principles of professional conduct concerning the rights and duties of the physician, relations with patients and fellow practitioners, as well as actions of the physician in patient care and interpersonal relations with patient families.

An enduring, learned predisposition to behave in a consistent way toward a given class of objects, or a persistent mental and/or neural state of readiness to react to a certain class of objects, not as they are but as they are conceived to be.

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).

Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.

The scientific disciplines concerned with the embryology, anatomy, physiology, biochemistry, pharmacology, etc., of the nervous system.

Exercise of governmental authority to control conduct.

The protection of animals in laboratories or other specific environments by promoting their health through better nutrition, housing, and care.

Organized activities related to the storage, location, search, and retrieval of information.

A branch of applied ethics that studies the value implications of practices and developments in life sciences, medicine, and health care.

Knowledge, attitudes, and associated behaviors which pertain to health-related topics such as PATHOLOGIC PROCESSES or diseases, their prevention, and treatment. This term refers to non-health workers and health workers (HEALTH PERSONNEL).

The portion of an interactive computer program that issues messages to and receives commands from a user.

Sequential operating programs and data which instruct the functioning of a digital computer.

The terms, expressions, designations, or symbols used in a particular science, discipline, or specialized subject area.

Individual's rights to obtain and use information collected or generated by others.

The concept concerned with all aspects of providing and distributing health services to a patient population.

The field of information science concerned with the analysis and dissemination of medical data through the application of computers to various aspects of health care and medicine.

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)

Federal, state, or local government organized methods of financial assistance.

A way of providing health care that is guided by a thoughtful integration of the best available scientific knowledge with clinical expertise. This approach allows the practitioner to critically assess research data, clinical guidelines, and other information resources in order to correctly identify the clinical problem, apply the most high-quality intervention, and re-evaluate the outcome for future improvement.

Those factors which cause an organism to behave or act in either a goal-seeking or satisfying manner. They may be influenced by physiological drives or by external stimuli.

Organizations and individuals cooperating together toward a common goal at the local or grassroots level.

The attitude of a significant portion of a population toward any given proposition, based upon a measurable amount of factual evidence, and involving some degree of reflection, analysis, and reasoning.

A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.

Societies whose membership is limited to physicians.

Patient involvement in the decision-making process in matters pertaining to health.

That segment of commercial enterprise devoted to the design, development, and manufacture of chemical products for use in the diagnosis and treatment of disease, disability, or other dysfunction, or to improve function.

Application of statistical procedures to analyze specific observed or assumed facts from a particular study.

Social and economic factors that characterize the individual or group within the social structure.

Spread and adoption of inventions and techniques from one geographic area to another, from one discipline to another, or from one sector of the economy to another. For example, improvements in medical equipment may be transferred from industrial countries to developing countries, advances arising from aerospace engineering may be applied to equipment for persons with disabilities, and innovations in science arising from government research are made available to private enterprise.

Attitudes of personnel toward their patients, other professionals, toward the medical care system, etc.

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.

Time period from 1801 through 1900 of the common era.

A collective expression for all behavior patterns acquired and socially transmitted through symbols. Culture includes customs, traditions, and language.

The exchange or transmission of ideas, attitudes, or beliefs between individuals or groups.

Public attitudes toward health, disease, and the medical care system.

Documents describing a medical treatment or research project, including proposed procedures, risks, and alternatives, that are to be signed by an individual, or the individual's proxy, to indicate his/her understanding of the document and a willingness to undergo the treatment or to participate in the research.

Assessment of psychological variables by the application of mathematical procedures.

Acquisition of knowledge as a result of instruction in a formal course of study.

Organized collections of computer records, standardized in format and content, that are stored in any of a variety of computer-readable modes. They are the basic sets of data from which computer-readable files are created. (from ALA Glossary of Library and Information Science, 1983)

All organized methods of funding.

A subspecialty of internal medicine concerned with the study of neoplasms.

A course or method of action selected to guide and determine present and future decisions.

The purposes, missions, and goals of an individual organization or its units, established through administrative processes. It includes an organization's long-range plans and administrative philosophy.

A generic concept reflecting concern with the modification and enhancement of life attributes, e.g., physical, political, moral and social environment; the overall condition of a human life.

Published materials which provide an examination of recent or current literature. Review articles can cover a wide range of subject matter at various levels of completeness and comprehensiveness based on analyses of literature that may include research findings. The review may reflect the state of the art. It also includes reviews as a literary form.

Organizations established by endowments with provision for future maintenance.

Studies beyond the bachelor's degree at an institution having graduate programs for the purpose of preparing for entrance into a specific field, and obtaining a higher degree.

Theoretical representations and constructs that describe or explain the structure and hierarchy of relationships and interactions within or between formal organizational entities or informal social groups.

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

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

Clusters of topics that fall within the domain of BIOETHICS, the field of study concerned with value questions that arise in biomedicine and health care delivery.

Experimentation on, or using the organs or tissues from, a human or other mammalian conceptus in the postembryonic period, after the major structures have been outlined. In humans, this corresponds to the period from the third month after fertilization until birth.

Refusal to take part in activities or procedures that are requested or expected of an individual. This may include refusal by HEALTH PERSONNEL to participate in specific medical procedures or refusal by PATIENTS or members of the public to take part in clinical trials or health promotion programs.

Programs of study which span the traditional boundaries of academic scholarship.

Societies whose membership is limited to scientists.

Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.

The smallest continent and an independent country, comprising six states and two territories. Its capital is Canberra.

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.

Confidence in or reliance on a person or thing.

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.

Groups set up to advise governmental bodies, societies, or other institutions on policy. (Bioethics Thesaurus)

The reciprocal interaction of two or more professional individuals.

Stipends or grants-in-aid granted by foundations or institutions to individuals for study.

The guidelines and policy statements set forth by the editor(s) or editorial board of a publication.

Extensive collections, reputedly complete, of references and citations to books, articles, publications, etc., generally on a single subject or specialized subject area. Databases can operate through automated files, libraries, or computer disks. The concept should be differentiated from DATABASES, FACTUAL which is used for collections of data and facts apart from bibliographic references to them.

Directions or principles presenting current or future rules of policy for assisting health care practitioners in patient care decisions regarding diagnosis, therapy, or related clinical circumstances. The guidelines may be developed by government agencies at any level, institutions, professional societies, governing boards, or by the convening of expert panels. The guidelines form a basis for the evaluation of all aspects of health care and delivery.

The application of technology to the solution of medical problems.

Psychiatric illness or diseases manifested by breakdowns in the adaptational process expressed primarily as abnormalities of thought, feeling, and behavior producing either distress or impairment of function.

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.

A field of biology concerned with the development of techniques for the collection and manipulation of biological data, and the use of such data to make biological discoveries or predictions. This field encompasses all computational methods and theories for solving biological problems including manipulation of models and datasets.

Disorders related to substance abuse.

The science and technology dealing with the procurement, breeding, care, health, and selection of animals used in biomedical research and testing.

A quantitative measure of the frequency on average with which articles in a journal have been cited in a given period of time.

Field of medicine concerned with the determination of causes, incidence, and characteristic behavior of disease outbreaks affecting human populations. It includes the interrelationships of host, agent, and environment as related to the distribution and control of disease.

Persons living in the United States having origins in any of the black groups of Africa.

The act or fact of grasping the meaning, nature, or importance of; understanding. (American Heritage Dictionary, 4th ed) Includes understanding by a patient or research subject of information disclosed orally or in writing.

Stress wherein emotional factors predominate.

The aggregate of social and cultural institutions, forms, patterns, and processes that influence the life of an individual or community.

Individuals enrolled in a school or formal educational program.

The concept pertaining to the health status of inhabitants of the world.

The body of truths or facts accumulated in the course of time, the cumulated sum of information, its volume and nature, in any civilization, period, or country.

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.

Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps.

Abstract standards or empirical variables in social life which are believed to be important and/or desirable.

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

The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.

Intellectual or mental process whereby an organism obtains knowledge.

Institutional committees established to protect the welfare of animals used in research and education. The 1971 NIH Guide for the Care and Use of Laboratory Animals introduced the policy that institutions using warm-blooded animals in projects supported by NIH grants either be accredited by a recognized professional laboratory animal accrediting body or establish its own committee to evaluate animal care; the Public Health Service adopted a policy in 1979 requiring such committees; and the 1985 amendments to the Animal Welfare Act mandate review and approval of federally funded research with animals by a formally designated Institutional Animal Care and Use Committee (IACUC).

A severe emotional disorder of psychotic depth characteristically marked by a retreat from reality with delusion formation, HALLUCINATIONS, emotional disharmony, and regressive behavior.

The reciprocal interaction of two or more persons.

Component of the NATIONAL INSTITUTES OF HEALTH. Through basic and clinical biomedical research and training, it conducts and supports research with the objective of cancer prevention, early stage identification and elimination. This Institute was established in 1937.

The philosophy or code pertaining to what is ideal in human character and conduct. Also, the field of study dealing with the principles of morality.

An infant during the first month after birth.

The external elements and conditions which surround, influence, and affect the life and development of an organism or population.

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

The state of being free from intrusion or disturbance in one's private life or affairs. (Random House Unabridged Dictionary, 2d ed, 1993)

Education that increases the awareness and favorably influences the attitudes and knowledge relating to the improvement of health on a personal or community basis.

Administrative units of government responsible for policy making and management of governmental activities.

A method of comparing the cost of a program with its expected benefits in dollars (or other currency). The benefit-to-cost ratio is a measure of total return expected per unit of money spent. This analysis generally excludes consideration of factors that are not measured ultimately in economic terms. Cost effectiveness compares alternative ways to achieve a specific set of results.

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

The medical science that deals with the origin, diagnosis, prevention, and treatment of mental disorders.

The educational process of instructing.

A course of study offered by an educational institution.

Use for general articles concerning medical education.

A medical specialty concerned with maintaining health and providing medical care to children from birth to adolescence.

Component of the NATIONAL INSTITUTES OF HEALTH. It seeks to improve oral, dental and craniofacial health through research, research training, and the dissemination of health information by conducting and supporting basic and clinical research. It was established in 1948 as the National Institute of Dental Research and re-named in 1998 as the National Institute of Dental and Craniofacial Research.

The ability to understand the nature and effect of the act in which the individual is engaged. (From Black's Law Dictionary, 6th ed).

Duties that are based in ETHICS, rather than in law.

Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.

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

A state of harmony between internal needs and external demands and the processes used in achieving this condition. (From APA Thesaurus of Psychological Index Terms, 8th ed)