1. Optimized Group Sequential Study Designs for Tests of Genetic Linkage and Association in Complex Diseases 
Inke R. König, Helmut Schäfer, Hans-Helge Müller, Andreas Ziegler 
The American Journal of Human Genetics 
Volume 69, Issue 3, Pages (September 2001)
DOI: /323250
Copyright © 2001 The American Society of Human Genetics Terms and Conditions

2. Figure 1
Simulated average sample sizes for the one-sided mean test under H0 and H1. α=.0001, and β=.2; number of replications = 3,900,000 under H0 and 700,000 under H1. Gray line, simulated average sample sizes in the fixed-sample design. Solid and dotted black lines, simulated average sample sizes in the group sequential designs with two and three stages, respectively.
The American Journal of Human Genetics  , DOI: ( /323250)
Copyright © 2001 The American Society of Human Genetics Terms and Conditions