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Covariate imbalance and random allocation in clinical trials
Abstract
A model is developed to estimate the effect of covariate imbalance on the size of a test of treatment efficacy in randomized clinical trials comparing two treatments when dispersion parameters are known. It is concluded that tests of homogeneity on the covariates should not be performed, that covariate imbalance is just as much a problem for large studies as for small ones in terms of effect on size, and that the effect of correlation between covariates and measures of efficacy is more complex than has previously been sugested. The best way to adjust for covariate imbalance is by an analysis of covariance.
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Citations
Cited by
Austin, P. C. (2009) · Statistics in Medicine · doi:10.1002/sim.3697 · Cited by 6,758
Subgroup analysis and other (mis)uses of baseline data in clinical trials
Assmann, S. F., Pocock, S. J., Enos, L. E., & Kasten, L. E. (2000) · The Lancet · doi:10.1016/s0140-6736(00)02039-0 · Cited by 1,167
Assessing the Generalizability of Prognostic Information
Justice, A. C., Covinsky, K. E., & Berlin, J. A. (1999) · Annals of Internal Medicine · doi:10.7326/0003-4819-130-6-199903160-00016 · Cited by 1,160
Pocock, S. J., Assmann, S. E., Enos, L. E., & Kasten, L. E. (2002) · Statistics in Medicine · doi:10.1002/sim.1296 · Cited by 1,077
Confounding and Collapsibility in Causal Inference
Greenland, S., Pearl, J., & Robins, J. M. (1999) · Statistical Science · doi:10.1214/ss/1009211805 · Cited by 933
Metadata
- Authors
- Senn, S. J.
- Venue
- Statistics in Medicine
- Publisher
- Wiley
- Published
- 1989-04
- Volume
- 8
- Issue
- 4
- Pages
- 467-475
- ISSN
- 0277-6715 (ISSN-L)
- 1097-0258
- OpenAlex
- W2043458654
- Cited by
- 279
- References
- 0
- FWCI
- 6.89
- Type
- journal article
- Language
- en
- Open access
- closed
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