Familial Risk and Heritability of Cancer Among Twins in Nordic Countries.

Importance: Estimates of familial cancer risk from population-based studies are essential components of cancer risk prediction.

Objective: To estimate familial risk and heritability of cancer types in a large twin cohort.

Design, Setting, And Participants: Prospective study of 80,309 monozygotic and 123,382 same-sex dizygotic twin individuals (N = 203,691) within the population-based registers of Denmark, Finland, Norway, and Sweden.

Global teaching and training initiatives for emerging cohort studies.

A striking disparity exists across the globe, with essentially no large-scale longitudinal studies ongoing in regions that will be significantly affected by the oncoming non-communicable disease epidemic. The successful implementation of cohort studies in most low-resource research environments presents unique challenges that may be aided by coordinated training programs. Leaders of emerging cohort studies attending the First World Cohort Integration Workshop were surveyed about training priorities, unmet needs and potential cross-cohort solutions to these barriers through an electronic pre-workshop questionnaire and focus groups.