How study design affects outcomes in comparisons of therapy. I: Medical

Statistics in Medicine - Tập 8 Số 4 - Trang 441-454 - 1989
Graham A. Colditz1, James N. Miller2, Frederick Mosteller3
1Channing Laboratory, Department of Medicine, Harvard Medical School and Brigham and Women's Hospital, 180 Longwood Avenue, Boston, MA 02115, U.S.A.
2Center for Science and International Affairs, John F. Kennedy School of Government, Harvard University, Cambridge, MA 02138, U.S.A.
3Technology Assessment Group, Department of Health Policy and Management, Harvard University School of Public Health, 677 Huntington Avenue, Boston, MA 02115, U.S.A.

Tóm tắt

AbstractWe analysed 113 reports published in 1980 in a sample of medical journals to relate features of study design to the magnitude of gains attributed to new therapies over old. Overall we rated 87 per cent of new therapies as improvements over standard therapies. The mean gain (measured by the Mann—Whitney statistic) was relatively constant across study designs, except for non‐randomized controlled trials with sequential assignment to therapy, which showed a significantly higher likelihood that a patient would do better on the innovation than on standard therapy (p = 0.004). Randomized controlled trials that did not use a double‐blind design had a higher likelihood of showing a gain for the innovation than did double‐blind trials (p = 0.02). Any evaluation of an innovation may include both bias and the true efficacy of the new therapy, therefore we may consider making adjustments for the average bias associated with a study design. When interpreting an evaluation of a new therapy, readers should consider the impact of the following average adjustments to the Mann—Whitney statistic: for trials with non‐random sequential assignment a decrease of 0.15, for non‐double‐blind randomized controlled trials a decrease of 0.11.

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Tài liệu tham khảo

Committee for Evaluating Medical Technologies in Clinical Use., 1985, Assessing Medical Technologies, 70

10.1056/NEJM197207132870205

10.1056/NEJM197711172972004

Sacks H. S., 1983, Randomized versus historical assignment in controlled clinical trials, New England Journal of Medicine, 309, 1353

Wortman P. M., 1983, Evaluation Studies Review Annual, 536

Gilbert J. P., 1977, Cost, Risks, and Benefits of Surgery, 124

10.2105/AJPH.72.4.359

Sackett D. L., 1981, Coping with the Biomedical Literature: A Primer for the Scientist and the Clinician

10.1002/9780470316542

Colditz G. A., 1988, The effected study designs on gains in the evaluations of new treatments on medicine and surgery, Drug Information Journal, 22, 10.1177/009286158802200307

Garfield E., 1980, Journal Citation Reports: A bibliometric analysis of science journals on the 1st data base, 12A

10.1056/NEJM198412063112305

DerSimonian R., 1984, Reporting on methods in clinical trials, New England Journal of Medicine, 311, 442

10.1016/0002-8703(80)90314-2

10.1378/chest.78.3.429

Shaikh W., 1976, A systematic review of the literature on evaluation studies of tonsillectomy and adenoidectomy, Pediatrics, 57, 401, 10.1542/peds.57.3.401

Colditz G. A. Miller J. N.andMosteller F.‘Measuring gain in the evaluation of medical technology: The probability of a better outcome’ International Journal of Technology Assessment Health Care (1988) (in press).

10.2105/AJPH.72.10.1103

10.2105/AJPH.72.10.1119

Fineberg H. V., 1985, Assessing Medical Technologies, 176

10.1016/0197-2456(82)90006-X

Chassin M. P., Health Technology Case Study, 24: Variations in hospital length of stay: Their relationship to health outcomes

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Statistics in Medicine

Tập 8 Số 4

441-454

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