An introduction into planning and implementing evaluation studies in child and adolescent psychiatry is presented. After the presentation of theoretical aspects of evaluation studies, the necessity of these studies is elucidated. Further, a conceptualisation of the dimensions of a treatment programme and some criteria for the selection of outcome criteria are offered. In addition to symptomatology, other criteria such as family functioning and quality of life are proposed in this context. Furthermore, it is recommended to ascertain data already at the time of the patient's registration. The influence of drop-out rate on the study result makes it necessary to closely consider any missing data. These and other problems lead to the conclusion that a sophisticated and complex evaluation methodology is required to assess the performance of a child and adolescent treatment programme validly. Finally, the design of the Hamburg evaluation study is presented, which is suitable for the implementation of some of the mentioned aspects.
