Sample size considerations for non-randomized comparative studies.

Abstract Historical controls are frequently used in the clinical evaluation of a new therapy. Sample size tables are needed for such non-randomized studies since these determinations can differ markedly from the widely published sample size estimates appropriate for randomized comparative studies. A comprehensive array of sample size tables are therefore provided to aid investigators in the planning of non-randomized comparative trials. The equations and tables presented in this paper reflect the extent to which the number of patients required to receive the new therapy depends on the number of historical controls selected for comparison. Guidelines for the use of historical controls and the pooling of several historical-control groups are discussed.

[1]  H. N. Magoun Thomas, Springfield, Illinois , 1965 .

[2]  Max Halperin,et al.  Sample sizes for medical trials with special reference to long-term therapy , 1968 .

[3]  F. J. Anscombe,et al.  THE TRANSFORMATION OF POISSON, BINOMIAL AND NEGATIVE-BINOMIAL DATA , 1948 .

[4]  A. B. Hill Statistical Methods in Clinical and Preventive Medicine , 1962 .

[5]  J. Ware,et al.  Randomized clinical trials. Perspectives on some recent ideas. , 1976, The New England journal of medicine.

[6]  B. Pasternack Sample sizes for clinical trials designed for patient accrual by cohorts. , 1972, Journal of chronic diseases.

[7]  B. Pasternack,et al.  Planning the duration of long-term survival time studies designed for accrual by cohorts. , 1971, Journal of chronic diseases.

[8]  C. Dunnett,et al.  Significance testing to establish equivalence between treatments, with special reference to data in the form of 2X2 tables. , 1977, Biometrics.

[9]  G. W. Snedecor Statistical Methods , 1964 .

[10]  David R. Cox,et al.  Regression models and life tables (with discussion , 1972 .

[11]  J B Block,et al.  Controlled studies in clinical cancer research. , 1972, The New England journal of medicine.

[12]  R. Makuch,et al.  Sample size requirements for evaluating a conservative therapy. , 1978, Cancer treatment reports.

[13]  M. Gail The determination of sample sizes for trials involving several independent 2x2 tables. , 1973, Journal of chronic diseases.

[14]  E. Gehan,et al.  Non-randomized controls in cancer clinical trials. , 1974, The New England journal of medicine.

[15]  E. Gehan,et al.  Planning and analysis of clinical studies , 1971 .

[16]  J J Gart,et al.  The determination of sample sizes for use with the exact conditional test in 2 x 2 comparative trials. , 1973, Biometrics.

[17]  J. Lachin Sample size determinants for r X c comparative trials. , 1977, Biometrics.

[18]  D. Chanter Modifications of the Angular Transformation , 1975 .

[19]  S. Greenhouse,et al.  Determination of Sample Size and Selection of Cases. , 1959 .

[20]  S. Pocock Randomised clinical trials. , 1977, British medical journal.

[21]  S. George,et al.  Planning the size and duration of a clinical trial studying the time to some critical event. , 1974, Journal of chronic diseases.