The Avon Longitudinal Study of Parents and Children (ALSPAC) recruited 14,541 pregnant women residing in Avon, UK, with expected dates of delivery April 1, 1991, to December 31, 1992. The enrolled sample consisted of 14,775 children. Additional details are provided in the Supplemental Materials. For the current analyses, phenotypic data were available for up to 5,911 participants, depending on the phenotype and wave of assessment. Ethical approval for the study was obtained from the ALSPAC Ethics and Law Committee and the Local Research Ethics Committees.
