Health-related quality of life in children and adolescents in Germany: results of the BELLA study

Background The self-perceived health or health-related quality of life of children and adolescents is increasingly recognised as a relevant outcome in medical practice and public health research. Identifying children and adolescents with particularly low health-related quality of life allows for an early detection of hidden morbidity and health care needs. Objectives The present study investigates health-related quality of life in children and adolescents in Germany. Methods In the Mental Health Module (BELLA study) of the German National Health Interview and Examination Survey for Children and Adolescents (KiGGS), the parents of 2,863 children and adolescents aged 7-17 years, and 1,700 children and adolescents aged 11-17 years completed the KINDL-R quality of life questionnaire. Results The reliability (Cronbach's alpha = 0.86) and validity of the measurements using the parent-reported KINDL-R were confirmed. Means and percentiles were calculated for the total sample as well as for strata defined by age, sex, geographical region (east/west), migration status and socioeconomic status. Expected differences in health-related quality of life of children and adolescents from different social backgrounds and with different health statuses were demonstrated by differences in the KINDL-R scores (effect size d up to 1.29). Conclusion This study provides representative, normative data (self-report and parent-report) on the test scores of health-related quality of life (KINDL-R) for the population of children and adolescents in Germany in general, as well as in sociodemographic and socioeconomic subpopulations.