Association between participation in the Northern Finland Birth Cohorts and cardiometabolic disorders.

The results suggest that participation in the NFBC1986 may have a weak positive health effect among men. Agreement to follow-up studies focusing on diet, substance use, and physical activity, may slightly decrease the incident risk of cardiometabolic disorders in the study population.KEY MESSAGESEven mild interventions, such as follow-up studies in the prospective follow-up studies, might affect participants' behaviour and consequently the incidence of cardiometabolic disordersThe fact that follow-up itself might affect the study population in terms of risk factors, has to be taken into account when estimating the representativeness of the followed population.