It is well understood that statistical power to detect a variant of a given effect through a GWAS increases with both sample size and the density of markers across the genome 1, but power also depends ...

Missing data are a frequently encountered problem in epidemiologic and clinical research.1, 2 One approach is to include in the analysis only those participants without missing observations (complete ...

The plots used by Viale et al 2 are one way of exploring prognostic effects of continuous variables nonparametrically, but a more relevant question is that of an interaction between treatment and a ...

One way of viewing covariates is as extra sources of variation in the dependent variable that may mask the variation due to primary factors. This example demonstrates the use of the COVAR= option in ...

In addition to finding optimal block designs, you can use the BLOCKS statement to find designs that are optimal with respect to more general covariate models. You can specify the data set containing ...