Abstract
AIMS: The development of psychopathology during childhood and adolescence is complex and likely to follow diverse patterns. Mapping trajectories of psychopathological difficulties may improve our understanding of the nature of emerging, resolving and persistent psychopathology. The purpose of this study is to examine trajectories of psychopathology throughout childhood and adolescence by examining multiple data sources, including questionnaire-based reports of emotional and behavioural difficulties, psychiatric diagnoses and prescribed psychotropic medications. METHODS: Group-based multi-trajectory modelling was used to identify the psychopathological trajectories. This study included 49,361 full-term live-born singleton children born between 1996 and 2003, recruited into the Danish National Birth Cohort. Strengths and Difficulties Questionnaire data were collected when the children/adolescents were 7, 11 and 18 years old. Annual information about psychiatric diagnoses and redeemed prescriptions for psychotropic medication was retrieved from nationwide registries between the ages of 1 and 18. We included six predefined dimensions to identify the trajectories: internalizing behavioural problems, externalizing behavioural problems, neurodevelopmental diagnoses, affective diagnoses, mixed psychiatric diagnoses and psychotropic medications. RESULTS: Six distinct trajectory groups were identified for both boys and girls. Approximately 6% of the boys and 8% of the girls receive the bulk of the psychiatric diagnoses and psychotropic medications. We found no support for 'pure' internalizing or externalizing patterns in any identified trajectory, as problems in one dimension often indicated the presence of problems in another dimension. CONCLUSIONS: Our results demonstrate substantial psychiatric comorbidity and add new insights to the understanding of child and adolescent well-being and the complex patterns of developmental psychopathology.