[Detection and reduction of mental and motor disorders in childhood. 2. Fundamentals and risks in longitudinal research in pediatrics].

The study characterizes basic types of longitudinal research designs for the long-term follow-up of children in health and disease. First the authors mention briefly the principles and disadvantages of cross-sectional research designs. Then they present a detailed account of methods of longitudinal research projects, evaluation of their advantages and their risks. Roughly fifty-year experience with longitudinal designs indicates that this pretentious research strategy can provide an overall view of developmental trends as regards changes of the health status of children in the ontogenetic perspective and contribute to improvement of health care of the child population.