Selection of the multi-SNP model. (A) Reduction in the −2 log likelihood comparing the best 1 SNP, 2 SNP, … 8 SNP model from the study data (—) as well as expected reduction resulting from chance (). (B) Ranking of the percentage of 1000 stepwise bootstrap Cox models that included each SNP. The top 4 SNPs in the bootstrap model are the same 4 SNPs in the best 4 SNP risk model.