For an extrem-sibpair (ESP) study design using both extremely discordant and concordant (EDAC) sibpairs, this web-based utility calculates necessary numbers of various types of extreme sibpairs for a desired power, or estimates the power for a given configuration of different types of ESPs. Please refer to papers listed at the end of this page for details. Note that the optimization procedure described in the papers was not implemented in this web calculator.
1. Gu C, Todorov AA and Rao DC. Combining extremely concordant sibpairs with extremely discordant sibpairs provides a cost effective way to linkage analysis of QTL. Genetic Epidemiology 13:513-533, 1996.
2. Gu C and Rao DC. A linkage strategy for detection of human quantitative-trait loci: I. Generalized relative risk ratios and power of sib pairs with extreme trait values. American Journal of Human Genetics 61:200-210, 1997.
3. Gu C and Rao DC. A linkage strategy for detection of human quantitative-trait loci: II. Optimization of study designs based on extreme sib pairs and generalized relative risk ratios. American Journal of Human Genetics 61:211-222, 1997.