Longitudinal research on the developmental epidemiology of mental disorders: Aims, concepts and major results of the Mannheim Study of Risk Children

Background: The follow-up of risk groups is considered the "via regia" of t he developmental epidemiology of mental disorders. Objective: To follow the development of children born with different risks and to identify risk and protective factors for various developmental outcomes, as well as to analy ze the mechanisms underlying heterogeneous courses. Method: In a prospectiv e longitudinal study (with assessments at 3 months, 2, 4 1/2, 8, and lr yea rs) the onset and course of developmental and behavioral disorders in 384 c hildren was investigated. Organic (obstetric complications) and psychosocia l risks (family adversity) were varied in a two-factorial design. Results: The negative impact of early risk factors persisted into school age. While organic complications were associated with to disturbances in motor and cog nitive development, the adverse effects of psychosocial adversity pertained to cognitive and social-emotional functioning. Both risks contributed addi tively to outcome. Conclusions: Early risk factors have specific and long-t en sequelae. Children with multiple risks exhibit the most unfavourable dev elopment.