number of risk alleles (see thresholds below) by the negative logarithm (base 10) of the p-value and by the sign of the effect size. Clumping was done with respect to the linkage disequilibrium (LD) pattern in the COGA European ancestry sample (founders only) using a 500 kb physical distance and an LD threshold of r2 ≥ 0.10. Scores representing effect sizes with nine decreasing thresholds of statistical significance in the discovery GWAS were constructed (P < 0.0001, P < 0.001, P < 0.01, P < 0.05, P < 0.1, P < 0.2, P < 0.3, P < 0.4, P < 0.5). For subsequent use in association analysis, PRS values were z-scored. To aid in the interpretation, PRS values were z-scored so that effect sizes could be expressed as standard deviations of coherence values per standard deviation of PRS.
