The Young Researcher's Guide to Starting a Cohort Study.

A formally recruited, studied, and followed cohort is a rich source of data for a wide range of research questions; the larger the cohort, the greater the quantity of data systematically collected, and the longer the duration of follow-up, the greater the value of the cohort. Despite the ease of conducting cohort studies and the research value of such studies, few centers with long-term research goals conduct such studies. This article provides easy-to-understand practical guidance on how to start and run a cohort study.