Competing risks analyses for recurrence from primary breast cancer.
(49/30946)
The effects of prognostic factors on local, regional or distant metastasis are standardly assessed separately. Competing risks analyses may be used to assess simultaneously the effects of factors on different types of first recurrence. Data for a cohort of 678 primary invasive breast cancer patients accrued between 1971 and 1990, updated to 1995, included type of first recurrence (local, regional, distant). We investigated the effects of the traditional factors of age, tumour size, nodal status, ER, PgR, adjuvant therapy (hormones, chemotherapy, radiotherapy) on type of recurrence and time to recurrence for all patients and for those aged > or = 65. For all ages of patients, there were five factors with significant associations with type or time to first recurrence. Adjuvant radiation was the only factor which had an effect (P < or = 0.05) on the type of first recurrence: being associated with a reduction in local recurrence. Age, nodal status, tumour size and adjuvant chemotherapy all had significant associations across all types of first recurrence, and in particular with time to recurrence for both local and distant metastasis. This indicates a potential lack of independence in these end-points. For patients > or = 65 years of age, there were no factors which differentially affected type of recurrence, while only nodal status and tumour size had significant associations with time to recurrence. Analyses were used to assess simultaneously the effects of traditional prognostic factors and treatment options on type of first recurrence and time to first recurrence. The extension to evaluations with newer prognostic factors would expedite the determination and mode of biologic activity for such factors. (+info)
Preventing injuries in children: cluster randomised controlled trial in primary care.
(50/30946)
OBJECTIVE: To assess the effectiveness of safety advice at child health surveillance consultations, provision of low cost safety equipment to families receiving means tested state benefits, home safety checks, and first aid training on frequency and severity of unintentional injuries in children at home. DESIGN: Cluster randomised controlled trial. SETTING: 36 general practices in Nottingham. SUBJECTS: All children aged 3-12 months registered with participating practices. INTERVENTIONS: A package of safety advice at child health surveillance consultations at 6-9, 12-15, and 18-24 months; provision of low cost safety equipment to families on means tested state benefits; and home safety checks and first aid training by health visitors. OUTCOME MEASURES: Primary outcomes measures were frequency and severity of medically attended injuries. Secondary outcome measures were self reported safety practices, possession and use of safety equipment, knowledge and confidence in dealing with first aid, and perceptions of risk of injury and risk of hazards assessed by postal questionnaire at baseline and follow up at 25 months. RESULTS: At baseline, both groups had similar risk factors for injury, sociodemographic characteristics, safety practices, possession and use of safety equipment, knowledge and confidence in dealing with first aid, and perceptions of risk. No significant difference was found in frequency of at least one medically attended injury (odds ratio 0.97, 95% confidence interval 0.72 to 1.30), at least one attendance at an accident and emergency department for injury (1.02, 0.76 to 1.37), at least one primary care attendance for injury (0.75, 0.48 to 1.17), or at least one hospital admission for injury (0.69, 0.42 to 1.12). No significant difference in the secondary outcome measures was found between the intervention and control groups. CONCLUSIONS: The intervention package was not effective in reducing the frequency of minor unintentional injuries in children at home, and larger trials are required to assess the effect on more severe injuries. (+info)
Reducing antibiotics for respiratory tract symptoms in primary care: consolidating 'why' and considering 'how'.
(51/30946)
We summarize recently published evidence showing that antibiotic treatment offers little or no benefit to most patients presenting with sore throats, acute otitis media, maxillary sinusitis, and acute bronchitis. Despite this research, the prescription of antibiotics for respiratory tract conditions is rising in Britain. This wastes money, encourages people to consult for self-limiting conditions, and causes bacteria to become resistant to antimicrobials. Ways of changing present practice are underresearched. Enhanced consulting skills, guidelines and monitoring strategies, patient education, and anti-inflammatory drugs for recurrent and chronic sufferers all hold promise. (+info)
Barriers between guidelines and improved patient care: an analysis of AHCPR's Unstable Angina Clinical Practice Guideline. Agency for Health Care Policy and Research.
(52/30946)
OBJECTIVES: To describe common barriers that limit the effect of guidelines on patient care, with emphasis on recommendations for triage in the Agency for Health Care Policy and Research (AHCPR) Unstable Angina Clinical Practice Guideline. DATA SOURCES: Previously reported results from a prospective clinical study of 10,785 patients presenting to the emergency department (ED) with symptoms suggestive of acute cardiac ischemia. STUDY DESIGN: Design is an analysis of the AHCPR guideline with regard to recognized barriers in guideline implementation. Presentation of hypothetical scenarios to ED physicians was used to determine interrater reliability in applying the guideline to assess risk and to make triage decisions. PRINCIPAL FINDINGS: The AHCPR guideline's triage recommendations demonstrate (1) poor interobserver reliability in interpretation by ED physicians; (2) limited applicability of recommendations for outpatient management (applies to 6 percent of patients presenting to the ED with unstable angina); (3) incomplete specifications of exceptions that may require deviation from guideline recommendations; (4) unexpected effects on medical care by significantly increasing the demand for limited intensive care beds; and (5) unknown effects on patient outcomes. In addition, analysis of the guideline highlights the need to address organizational barriers, such as administrative policies that conflict with guideline recommendations and the need to adapt the guideline to conform to local systems of care. CONCLUSIONS: Careful analysis of guideline attributes, projected effect on medical care, and organizational factors reveal several barriers to successful guideline implementation that should be addressed in the design of future guideline-based interventions. (+info)
An outbreak of hepatitis A associated with an infected foodhandler.
(53/30946)
OBJECTIVE: The recommended criteria for public notification of a hepatitis A virus (HAV)-infected foodhandler include assessment of the foodhandler's hygiene and symptoms. In October 1994, a Kentucky health department received a report of a catering company foodhandler with hepatitis A. Patrons were not offered immune globulin because the foodhandler's hygiene was assessed to be good and he denied having diarrhea. During early November, 29 cases of hepatitis A were reported among people who had attended an event catered by this company. Two local health departments and the Centers for Disease Control and Prevention, in collaboration with two state health departments, undertook an investigation to determine the extent of the outbreak, to identify the foods and event characteristics associated with illness, and to investigate the apparent failure of the criteria for determining when immune globulin (IG) should be offered to exposed members of the public. METHODS: Cases were IgM anti-HAV-positive people with onset of symptoms during October or November who had eaten foods prepared by the catering company. To determine the outbreak's extent and factors associated with illness, the authors interviewed all case patients and the infected foodhandler and collected information on menus and other event characteristics. To investigate characteristics of events associated with transmission, the authors conducted a retrospective analysis comparing the risk of illness by selected event characteristics. To evaluate what foods were associated with illness, they conducted a retrospective cohort study of attendees of four events with high attack rates. RESULTS: A total of 91 cases were identified. At least one case was reported from 21 (51%) of the 41 catered events. The overall attack rate was 7% among the 1318 people who attended these events (range 0 to 75% per event). Attending an event at which there was no on-site sink (relative risk [RR] = 2.3, 95% confidence interval [CI] 1.4, 3.8) or no on-site kitchen (RR = 1.9, 95% Cl 1.1, 2.9) was associated with illness. For three events with high attack rates, eating at least one of several uncooked foods was associated with illness, with RRs ranging from 8 to undefined. CONCLUSION: A large hepatitis A outbreak resulted from an infected foodhandler with apparent good hygiene and no reported diarrhea who prepared many uncooked foods served at catered events. Assessing hygiene and symptoms s subjective, and may be difficult to accomplish. The effectiveness of the recommended criteria for determining when IG should be provided to exposed members of the public needs to be evaluated. (+info)
Significance of vomiting after head injury.
(54/30946)
OBJECTIVES: To determine whether the presence and severity of post-traumatic vomiting can predict the risk of a skull vault fracture in adults and children. METHODS: Data were analysed relating to a consecutive series of 5416 patients including children who presented to an emergency service in the United Kingdom during a 1 year study period with a principal diagnosis of head injury. Characteristics studied were age, sex, speed of impact, level of consciousness on arrival, incidence of skull fracture, and the presence and severity of post-traumatic vomiting. RESULTS: The overall incidence of post-traumatic vomiting was 7% in adults and 12% in children. In patients with a skull fracture the incidence of post-traumatic vomiting was 28% in adults and 33% in children. Post-traumatic vomiting was associated with a fourfold increase in the relative risk for a skull fracture. Nausea alone did not increase the risk of a skull fracture and multiple episodes of vomiting were no more significant than a single episode. In patients who were fully alert at presentation, post-traumatic vomiting was associated with a twofold increase in relative risk for a skull fracture. CONCLUSION: These results support the incorporation of enquiry about vomiting into the guidelines for skull radiography. One episode of vomiting seems to be as significant as multiple episodes. (+info)
An evaluation of "informed consent" with volunteer prisoner subjects.
(55/30946)
"Informed consent" sets a goal for investigators experimenting with human subjects, but little is known about how to achieve or evaluate it in an experiment. In a 3-year, double-blind study with incarcerated men, we attempted to provide a "free and informed consent" and evaluated our efforts with an unannounced questionnaire administered to subjects after they completed the experiment. At that time, approximately two-thirds had sufficient information for an informed consent, but only one-third was well informed about all key aspects of the experiment and one-third was insufficiently informed to give an informed consent. We found that institution- or study-based coercion was minimal in our experiment. From our evaluation of the questionnaire and experience at the study institution, we conclude that an experiment with human subjects should be designed to include an ongoing evaluation of informed consent, and active attempts should be made to avoid or minimize coercive inducements. Experiments with significant risk, which require a long duration and/or large sample size relative to the institution's population, should probably not be performed on prisoner subjects. The experimenter should be independent of the penal institution's power structure. Presenting and explaining a consent form to volunteers on one occasion is probably an in adequate procedure for obtaining and maintaining an informed consent. (+info)
Intake of vitamins B6 and C and the risk of kidney stones in women.
(56/30946)
Urinary oxalate is an important determinant of calcium oxalate kidney stone formation. High doses of vitamin B6 may decrease oxalate production, whereas vitamin C can be metabolized to oxalate. This study was conducted to examine the association between the intakes of vitamins B6 and C and risk of kidney stone formation in women. The relation between the intake of vitamins B6 and C and the risk of symptomatic kidney stones were prospectively studied in a cohort of 85,557 women with no history of kidney stones. Semiquantitative food-frequency questionnaires were used to assess vitamin consumption from both foods and supplements. A total of 1078 incident cases of kidney stones was documented during the 14-yr follow-up period. A high intake of vitamin B6 was inversely associated with risk of stone formation. After adjusting for other dietary factors, the relative risk of incident stone formation for women in the highest category of B6 intake (> or =40 mg/d) compared with the lowest category (<3 mg/d) was 0.66 (95% confidence interval, 0.44 to 0.98). In contrast, vitamin C intake was not associated with risk. The multivariate relative risk for women in the highest category of vitamin C intake (> or =1500 mg/d) compared with the lowest category (<250 mg/d) was 1.06 (95% confidence interval, 0.69 to 1.64). Large doses of vitamin B6 may reduce the risk of kidney stone formation in women. Routine restriction of vitamin C to prevent stone formation appears unwarranted. (+info)