A note on appropriate use of statistical tests of mutation rates from ordered groups.
Recently it was found that the frequency of familial dysautonomia (FD) carriers in Ashkenazi Jews (AJ) was higher in AJ of Polish descent compared to AJ of non-Polish descent. The study population was classified into groups ranging from no to full Polish origin. The statistical procedure used to compare the frequencies of FD carriers did not incorporate this intrinsic ordering of individuals by degree of Polish ancestry. In this paper we describe a test designed to utilize this information and show that it is more powerful than the standard test of equality of proportions. In particular, the p value of the trend test on their data is noticeably lower (0.003) than 0.012 found by the standard test, providing stronger evidence for a relationship between allele frequency and Polish descent.
Gastwirth
Joseph L
JL
Department of Statistics, George Washington University, Washington, DC 20052, USA. jlgast@gwu.edu
Freidlin
Boris
B
D003627:Data Interpretation, Statistical; D004402:Dysautonomia, Familial / Q000235:genetics; D020022:Genetic Predisposition to Disease; D006801:Humans; D007585:Jews / Q000235:genetics; D009154:Mutation; D011044:Poland; D015203:Reproducibility of Results; D012307:Risk Factors