To enhance mental healthcare, it is important to measure the effectiveness of a treatment. Currently, there is a focus on clinical symptoms when evaluating mental healthcare. This longitudinal...Show moreTo enhance mental healthcare, it is important to measure the effectiveness of a treatment. Currently, there is a focus on clinical symptoms when evaluating mental healthcare. This longitudinal retrospective study examined whether the focus on clinical symptoms for children with an intellectual disability (ID) and psychopathology is justified, or if it should prioritize a more comprehensive examination of adaptive functioning. Therefore, it examines the associations between clinical symptoms and adaptive functioning before and after treatment for these children, compared to children with psychopathology alone. Furthermore, it investigates the differences between these groups regarding the changes in clinical symptoms and adaptive functioning during treatment and examines the association between those changes. Participants included children with and without an ID who received mental healthcare. Clinical symptoms and adaptive functioning were measured using the Strengths and Difficulties Questionnaire. Fisher’s Z-test showed that there was no difference between the groups regarding the association between clinical symptoms and adaptive functioning before treatment (Z= .658, p= 0.510). However, the association was weaker for children with an ID and psychopathology after treatment (Z= -2.241, p= .025). Furthermore, ANCOVA analysis showed a difference between the groups regarding changes in clinical symptoms during treatment (F= 12.72, p< .001), indicating that children with an ID and psychopathology showed less, or less rapid, improvements in clinical symptoms during treatment than children with psychopathology alone. However, there was no difference regarding the changes in adaptive functioning during treatment (F= 1.39, p= .240). Regarding the association between those changes, there was no difference between the groups (Z= -1.55, p=.121), again demonstrated with a Fisher Z-test. These results highlight the importance to assess limitations in understanding and communication skills to choose a tailored intervention for children with an ID and psychopathology. Moreover, it emphasizes the need to re-evaluate the way we measure healthcare effectiveness for children with an ID. Instead of focusing primarily on clinical symptoms, there is a need for a comprehensive and nuanced approach to the understanding of their disability within their environment. Therefore, embracing a comprehensive framework to assess adaptive functioning is essential for improving the measurement of mental healthcare for children with an ID and psychopathology.Show less