Sponsored by:
Response to survey questionnaires is vital for social and behavioral research, and most analyses assume full and accurate response by survey participants. However, nonresponse is common and impedes proper interpretation and generalizability of results. We examined item nonresponse behavior across 109 questionnaire items from a large prospective epidemiological cohort, the UK Biobank (UKB; N=360,628). Phenotypic factor scores for two participant-selected nonresponse answers, "Prefer not to answer" (PNA) and "I don't know" (IDK), each predicted participant nonresponse in follow-up surveys, even when controlling for education and self-reported health. We performed genome-wide association studies on these factors and identified 37 genome-wide significant loci, and further validated these effects with polygenic scores in an independent study (N=3,414), gaining information that we could not have had from phenotypic data alone. PNA and IDK were highly genetically correlated with one another and with education, health, and income, with additional unique genetic effects observed for both PNA and IDK that enhance our understanding of nonresponse behaviors in survey research. We discuss how these effects may bias studies of traits correlated with nonresponse and demonstrate how using these results for IDK and PNA to correct for nonresponse bias could have a substantial effect on GWAS.