Representation of people with intellectual disabilities in randomised controlled trials on antipsychotic treatment for behavioural problems.

Background Behavioural problems are common in people with intellectual disability (ID) and are often treated with antipsychotics. Aim To establish the frequency and characteristics of people with ID included in randomised controlled trials (RCTs) on antipsychotic treatment for behavioural problems, and to investigate the quality of these RCTs. Methods A literature search in EMBASE, PubMed and Cochrane was performed and reviewed. Results People with ID participated in 27 of the 100 included RCTs. The RCTs were of good quality but smaller compared with trials in patients with dementia or schizophrenia (average sample sizes = 55, 124 and 374). In 13/27 trials no clear definition of ID was given. Over 25 different outcome measures were used to assess behavioural problems. Conclusions Studies in which people with ID are included are of a sufficient quality, but of a small size. The heterogeneity in the characteristics of the ID population included as well as in the applied assessment instruments makes performing meta-analyses unfeasible.