The DOI matches its Crossref record; 9 of the 9 references it cites were found in a registry or an index.
Internal pilot studies for estimating sample size
Abstract
We develop the idea of using data from the first ‘few’ patients entered in a clinical trial to estimate the final trial size needed to have specified power for rejecting H0 in favour of H1 if a real difference exists. When comparing means derived from Normally distributed data, there is no important effect on test size, power or expected trial size, provided that a minimum of about 20 degrees of freedom are used to estimate residual variance. Relative advantages and disadvantages of using larger internal pilot studies are presented. These revolve around crude expectations of the final study size, recruitment rate, duration of follow‐up and practical constraints on the ability to prevent the circulation of unblinded randomization codes to investigators and those involved in editing and checking data.
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Cites
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Goodman, W. K. (1989) · Archives of General Psychiatry · doi:10.1001/archpsyc.1989.01810110048007 · Cited by 7,712
A Note on the Generation of Random Normal Deviates
Box, G. E. P., & Muller, M. E. (1958) · The Annals of Mathematical Statistics · doi:10.1214/aoms/1177706645 · Cited by 3,401
The Yale-Brown Obsessive Compulsive Scale: II. Validity
Goodman, W. K. (1989) · Archives of General Psychiatry · doi:10.1001/archpsyc.1989.01810110054008 · Cited by 2,799
A Two-Sample Test for a Linear Hypothesis Whose Power is Independent of the Variance
Stein, C. (1945) · The Annals of Mathematical Statistics · doi:10.1214/aoms/1177731088 · Cited by 886
The role of internal pilot studies in increasing the efficiency of clinical trials
Wittes, J., & Brittain, E. (1990) · Statistics in Medicine · doi:10.1002/sim.4780090113 · Cited by 440
(1999) · Technometrics · doi:10.1080/00401706.1999.10485691 · Cited by 379
Interim analyses for monitoring clinical trials that do not materially affect the type I error rate
Gould, A. L. (1992) · Statistics in Medicine · doi:10.1002/sim.4780110107 · Cited by 145
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Sample sizes required for binomial trials when the true response rates are estimated
Gould, A. L. (1983) · Journal of Statistical Planning and Inference · doi:10.1016/0378-3758(83)90061-7 · Cited by 10
Cited by
Sample size of 12 per group rule of thumb for a pilot study
Julious, S. A. (2005) · Pharmaceutical Statistics · doi:10.1002/pst.185 · Cited by 3,068
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
Whitehead, A. L., Julious, S. A., Cooper, C. L., & Campbell, M. J. (2016) · Statistical Methods in Medical Research · doi:10.1177/0962280215588241 · Cited by 1,936
Sim, J., & Lewis, M. (2012) · Journal of Clinical Epidemiology · doi:10.1016/j.jclinepi.2011.07.011 · Cited by 1,036
Teare, M. D., Dimairo, M., Shephard, N., Hayman, A., Whitehead, A., & Walters, S. J. (2014) · Trials · doi:10.1186/1745-6215-15-264 · Cited by 773
Metadata
- Authors
- Birkett, M. A., & Day, S. J.
- Venue
- Statistics in Medicine
- Publisher
- Wiley
- Published
- 1994-12-15
- Volume
- 13
- Issue
- 23-24
- Pages
- 2455-2463
- ISSN
- 0277-6715 (ISSN-L)
- 1097-0258
- OpenAlex
- W2129512582
- Cited by
- 332
- References
- 9
- FWCI
- 0.83
- Type
- journal article
- Language
- en
- Open access
- closed
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Bibliographic data: Semantic Scholar, OpenAlex, Crossref.
Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
