Measurements
aggression, social dysfunction, autism
SECONDARY, DYSFUNCTION
The primary outcome was the sum of the aggressive incidents at either the residential or the daycare facility, as reported daily with the modified overt aggression scale (MOAS) by the support staff (Kay et al., As a secondary outcome, quality of life was measured with the Intellectual Disability Quality of Life Scale (IDQOL‐16). This self‐report scale consists of 16 statements, which were visualised with pictograms and were scored on a 5‐point Likert scale in the shape of faces (smiley's), with the leftmost face smiling and the rightmost face looking angry (Hoekman et al., The social dysfunction and aggression scale (SDAS‐11) is an 11‐item observer‐rated questionnaire used to measure social dysfunction and aggressive behaviour during the previous week. Support staff scored each item on a 5‐point Likert scale, ranging from 0 (not present) to 4 (extremely severe). The total score ranges from 0 to 44, with higher scores indicating more social dysfunctional and aggressive behaviour (Wistedt et al., The Dutch Healthy Diet Food Frequency Questionnaire (DHD) can be used to estimate the extent to which the eating pattern is in accordance with the Dutch guidelines for a healthy diet from 2015 (Looman et al., We used case file data provided by the healthcare organisations to obtain IQ scores, medication, autism spectrum diagnosis, and demographic characteristics of participants. This information was collected at baseline by the research assistant.