A note on power approximations for the transmission/disequilibrium test.
The transmission/disequilibrium test (TDT) is a popular method for detection of the genetic basis of a disease. Investigators planning such studies require computation of sample size and power, allowing for a general genetic model. Here, a rigorous method is presented for obtaining the power approximations of the TDT for samples consisting of families with either a single affected child or affected sib pairs. Power calculations based on simulation show that these approximations are quite precise. By this method, it is also shown that a previously published power approximation of the TDT is erroneous.
Knapp
M
M
Institute for Medical Statistics, University of Bonn, 53105 Bonn, Germany. knapp@imsdd.meb.uni-bonn.de
D000483:Alleles; D001714:Bipolar Disorder / Q000235:genetics; D002874:Chromosome Mapping / Q000379:methods / Q000706:statistics & numerical data*; D003198:Computer Simulation; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease / Q000235:genetics; D005838:Genotype; D006801:Humans; D016013:Likelihood Functions; D015810:Linkage Disequilibrium / Q000235:genetics*; D008297:Male; D016555:Matched-Pair Analysis; D008433:Mathematics; D008957:Models, Genetic; D009679:Nuclear Family; D016017:Odds Ratio; D018401:Sample Size; D014365:Tryptophan Hydroxylase / Q000235:genetics
D014365:Tryptophan Hydroxylase