General characteristics of participants in the two-stage GWAS.

aT-test was used to compare means of the continuous variables between the first and the second stage; Chi-square test was used to compare the differences for categorical variables.General characteristics of participants in the two-stage GWAS.采用t检验对第一阶段与第二阶段的连续变量均值进行比较；采用卡方检验对分类变量的组间差异进行比较。两阶段全基因组关联研究（Genome-Wide Association Study, GWAS）的参与者一般特征。