Interim Analyses in Randomized Clinical Trials: Ramifications and Guidelines for Practitioners
BiometricsPublished 1 March 1987
Nancy L. Geller, Stuart Pocock
Citations199
SJR quartileQ1
SJR score1.26
SNIP1.20
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Abstract
Recent developments in group sequential methods have had a great impact on the design and analysis of randomized clinical trials. The consequences for both planned and unplanned interim analyses are discussed using several real trials as illustrations. Guidelines for the conduct of interim analysis are given, including tables of nominal significance levels and required sample sizes for several group sequential plans. Areas in need of further theoretical advance include multiple endpoints, estimation of treatment differences, stratification, and design of multiple-armed trials.
Keywords
Mathematics
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