The SELCoH study is an epidemiological cohort study of randomly selected households within Southwark and Lambeth. The study is funded by the National Institute for Health Research (NIHR) Biomedical Research Centre at South London and Maudsley NHS Foundation Trust (SLaM) and the Institute of Psychiatry, Psychology & Neuroscience (IoPPN), King’s College London; The Guy's and St Thomas' Charity and the Economic and Social Research Council.