Cohort methods and applications in human biology.

Cohort studies can broadly be defined as any non-interventional study in which a group of individuals are recruited (at any point in their lives) and followed up over time. The UK does not have an equivalent "sequential" birth cohort study but instead has a series of much larger nationally representative birth cohort studies initiated in 1946, 1958, 1970, and 2000 (Elliott and Shepherd [9]; Power and Elliott [24]; Wadsworth et al. [30]; Kuh et al. [19]; Hansen [13]). Using data from the Cambridge Baby Growth Study (Prentice et al. [25]), the special issue paper by Ong et al. provides evidence that the prediction of childhood percentage body fat by infant weight gain is unlikely to be largely improved upon by incorporation of infant length and skinfold thickness data. The special issue paper by Hardy & O'Neill is a commentary outlining the work of CLOSER on harmonising existing data across the UK studies, developing a meta-data platform containing information (in one place) on what has been collected in which studies and when, and building capacity in the necessary advanced analytical skills for cross-cohort analyses of longitudinal data. [Extracted from the article]