of SI (“Did you ever in your life have thoughts of killing yourself? [Yes/No]” OR “Did you ever wish you were dead or would go to sleep and never wake up? [Yes/No]”), SP (“Did you ever have any intention to act [on these thoughts/on that wish]? [Yes/No]” AND, if so, (“Did you ever think about how you might kill yourself [e.g., taking pills, shooting yourself] OR work out a plan of how to kill yourself? [Yes/No]”)), and SA (“Did you ever make a suicide attempt [i.e., purposefully hurt yourself with at least some intention to die]? [Yes/No]”). All respondents who reported ideation (regardless of intent/plan) were asked if they had ever attempted suicide. SA was considered present if respondents endorsed ever purposefully hurting themselves with at least some intention to die. Army STARRS participants were genotyped using the Illumina OmniExpress and Exome array or the Illumina PsychChip array. Methods for quality control, imputation, ancestry assignment and PC analysis were described previously23. Briefly, the quality control parameters applied included SNP missingness <0.05, subject missingness <0.02; autosomal heterozygosity deviation; SNP missingness of <0.02; and deviation from Hardy–Weinberg equilibrium P < 1 × 10−6. Genotyped data were pre-phased using SHAPEIT24 and imputed using
