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Biomedical subjects

K Schulman

Publications and source records attributed to K Schulman.

7 recordsLinked to original sources

BRCA1 testing in families with hereditary breast-ovarian cancer. A prospective study of patient decision making and outcomes.

OBJECTIVES: To identify predictors of utilization of breast-ovarian cancer susceptibility (BRCA1 gene) testing and to evaluate outcomes of participation in a testing program. DESIGN: Prospective cohort study with baseline interview assessment of predictor variables (eg, sociodemographic factors, knowledge about hereditary cancer and genetic testing, perceptions of testing benefits, limitations, and risks). BRCA1 test results were offered after an education and counseling session in a research setting. Outcome variables (including depression, functional health status, and prophylactic surgery plans [follow-up only]) were assessed at baseline and 1-month follow-up interviews. PARTICIPANTS: Adult male and female members (n=279) of families with BRCA1-linked hereditary breast-ovarian cancer (HBOC). RESULTS: Of subjects who completed a baseline interview (n=192), 60% requested BRCA1 test results (43% of all study subjects requested results). Requests for results were more frequent for persons with health insurance (odds ration [OR], 3.74; 95% confidence interval [CI], 2.06-6.80); more first-degree relatives affected with breast cancer (OR, 1.59; 95% CI, 1.16-2.16); more knowledge about BRCA1 testing (OR, 1.85; 95% CI, 1.36-2.50); and indicating that test benefits are important (OR, 1.45; 95% CI, 1.13-1.86). At follow-up, noncarriers of BRCA1 mutations showed statistically significant reductions in depressive symptoms and functional impairment compared with carriers and nontested individuals. Individuals identified as mutation carriers did not exhibit increases in depression and functional impairment. Among unaffected women with no prior prophylactic surgery, 17% of carriers (2/12) intended to have mastectomies and 33% (4/12) to have oophorectomies. CONCLUSIONS: Only a subset of HBOC family members are likely to request BRCA1 testing when available. Rates of test use may be higher in persons of a higher socioeconomic status and those with more relatives affected with breast cancer. For some high-risk individuals who receive test results in a research setting that includes counseling, there may be psychological benefits. More research is needed to assess the generalizability of these results and evaluate the long-term consequences of BRCA1 testing.

Adult

Evaluation of quality of life for diverse patient populations.

Quality of life is used increasingly as a primary and secondary endpoint of clinical investigations of new therapies. Quality of life information may be especially useful for the assessment of cancer treatments, where increases in survival may be accompanied by detrimental side effects. The recognition of the importance of quality of life has led to the recent proliferation of cancer specific quality of life instruments. As more is understood about the heterogeneity of patient populations, however, we must assess how culturally defined factors may impact patient quality of life and its assessment. Quality of life instruments are diverse, ranging from those focusing on objective measures of functionality to those assessing subjective measures of patient preferences for their current health state. These instruments have been developed for use in the general population and for disease-specific populations. Assessment of the appropriateness of potential quality of life instruments in specific clinical settings, in addition to understanding the cultural diversity of the clinical population being studied, will guide the researcher in the choice of an appropriate quality of life instrument for cancer clinical trials.

Clinical Trials as Topic

Ethics, economics, and the publication policies of major medical journals.

OBJECTIVE: To evaluate aspects of the publication process that may affect the quality of the literature in clinical economics and biomedical ethics, and to learn about the policies of medical journals regarding disclosure of relationships between investigators and research sponsors. DESIGN: Mail survey. PARTICIPANTS: Editors in chief of 15 major medical journals. RESULTS: Twelve editors responded to the survey. Ten reported having statisticians among their editors, while only two had health economists and none had ethicists. Clinicians in the specialty field were almost always the primary reviewers of submissions, while methodologists (statisticians, health economists, or ethicists) were involved less frequently. Journals reported little knowledge of the training of their reviewers in these fields. While nine journals requested disclosure of the financial relationship between author and sponsor, only one inquired whether the sponsor's written approval was required prior to manuscript submission, and only one knew whether there was an independent steering committee for the study. CONCLUSIONS: These findings suggest that the peer review process can be strengthened to improve the quality of the medical literature in clinical economics and biomedical ethics. Journal editors also need to better understand the terms of research sponsorship agreements.

Biomedical Research

Confidence intervals for cost-effectiveness ratios: a comparison of four methods.

We evaluated four methods for computing confidence intervals for cost-effectiveness ratios developed from randomized controlled trials: the box method, the Taylor series method, the nonparametric bootstrap method and the Fieller theorem method. We performed a Monte Carlo experiment to compare these methods. We investigated the relative performance of each method and assessed whether or not it was affected by differing distributions of costs (normal and log normal) and effects (10% absolute difference in mortality resulting from mortality rates of 25% versus 15% in the two groups as well as from mortality rates of 55% versus 45%) or by differing levels of correlation between the costs and effects (correlations of -0.50, -0.25, 0.0, 0.25 and 0.50). The principal criterion used to evaluate the performance of the methods was the probability of miscoverage. Symmetrical miscoverage of the intervals was used as a secondary criterion for evaluating the four methods. Overall probabilities of miscoverage for the nonparametric bootstrap method and the Fieller theorem method were more accurate than those for the other the methods. The Taylor series method had confidence intervals that asymmetrically underestimated the upper limit of the interval. Confidence intervals for cost-effectiveness ratios resulting from the nonparametric bootstrap method and the Fieller theorem method were more dependably accurate than those estimated using the Taylor series or box methods. Routine reporting of these intervals will allow individuals using cost-effectiveness ratios to make clinical and policy judgments to better identify when an intervention is a good value for its cost.

Computer Simulation