The DOI matches its Crossref record; 5 of the 5 references it cites were found in a registry or an index.
The role of internal pilot studies in increasing the efficiency of clinical trials
Abstract
Investigators often design clinical trials without knowing precisely the values of such necessary parameters as the variances or the event rates in the control group. In order to determine reasonable values for such parameters, they may design a small pilot study external to the main trial. In this paper we propose designs, which we term internal pilot studies, that designate a portion of the main trial as a pilot phase. At the end of the internal pilot study, the investigators recompute preselected parameters and recalculate required sample size. The study then proceeds with the modifications dictated by the internal pilot. Final analyses of the results incorporate all data, disregarding the fact that part of the data came from a pilot phase. As one example of this type of design, we consider a study to compare two normally distributed means. By simulation, we show a numerical example for which the effect of the procedure on the α‐level is negligible, but the potential gain in power considerable. We urge considering a similar approach for a number of types of endpoints.
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Cites
A Two-Sample Test for a Linear Hypothesis Whose Power is Independent of the Variance
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A Prospective, Randomized, Controlled Trial of Prednisone for Dilated Cardiomyopathy
Parrillo, J. E., Cunnion, R. E., Epstein, S. E., Parker, M. M., Suffredini, A. F., Brenner, M., Schaer, G. L., Palmeri, S. T., Cannon, R. O., Alling, D., et al. (1989) · New England Journal of Medicine · doi:10.1056/nejm198910193211601 · Cited by 353
Self-citationSystolic Hypertension in the Elderly Program (SHEP): Antihypertensive efficacy of chlorthalidone
Hulley, S. B., Furberg, C. D., Gurland, B., McDonald, R., Perry, H. M., Schnaper, H. W., Schoenberger, J. A., Smith, W. M., & Vogt, T. M. (1985) · The American Journal of Cardiology · doi:10.1016/0002-9149(85)90404-7 · Cited by 197
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Cited by
A tutorial on pilot studies: the what, why and how
Thabane, L., Ma, J., Chu, R., Cheng, J., Ismaila, A., Rios, L. P., Robson, R., Thabane, M., Giangregorio, L., & Goldsmith, C. H. (2010) · BMC Medical Research Methodology · doi:10.1186/1471-2288-10-1 · Cited by 3,384
Design and analysis of pilot studies: recommendations for good practice
Lancaster, G. A., Dodd, S., & Williamson, P. R. (2004) · Journal of Evaluation in Clinical Practice · doi:10.1111/j..2002.384.doc.x · Cited by 2,572
Lakens, D. (2022) · Collabra Psychology · doi:10.1525/collabra.33267 · Cited by 1,962
Sim, J., & Lewis, M. (2012) · Journal of Clinical Epidemiology · doi:10.1016/j.jclinepi.2011.07.011 · Cited by 1,036
Evaluation of Experiments with Adaptive Interim Analyses
Bauer, P., & Kohne, K. (1994) · Biometrics · doi:10.2307/2533441 · Cited by 865
Metadata
- Authors
- Wittes, J., & Brittain, E.
- Venue
- Statistics in Medicine
- Publisher
- Wiley
- Published
- 1990-01
- Volume
- 9
- Issue
- 1-2
- Pages
- 65-72
- ISSN
- 0277-6715 (ISSN-L)
- 1097-0258
- OpenAlex
- W2171991128
- Cited by
- 440
- References
- 5
- FWCI
- 2.98
- Type
- journal article
- Language
- en
- Open access
- closed
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
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