The objective of the study described in this thesis was to examine several aspects of quality of
life (QoL) of children with psychiatric disorders. In Chapter 1, the background and the main
aims were presented. Because treatment effects for severe and chronic diseases have been
improved in the last decades, QoL emerged as an important outcome measure. For the present
thesis, a longitudinal study with two assessments across a one-year follow-up period was
conducted among 310 children and adolescents (aged 6-18 years) who had been referred to
outpatient mental health agencies. Besides, a community sample of 74 children without
psychiatric problems was included. The aims of this study were: (1) to assess the usefulness
of the Pediatric Quality of Life Inventory (PedsQL) as an instrument measuring QoL in
children with psychiatric problems, (2) to compare QoL of children with psychiatric problems
to QoL of children from the general population without psychiatric problems, (3) to compare
QoL of children with different psychiatric disorders, (4) to identify factors that are associated
with QoL, (5) to determine the course of QoL, and (6) to identify predictors of change in QoL
across time