Service use and outcomes
In many developed countries such as the UK there have been rapid moves away from institutionalized care towards community care for people with intellectual disabilities (ID). This has been in the context of changes in policy regarding the health and social care for people with ID (see Chapter 1). Over the same period it has become increasingly recognized that people with ID are actually more likely to have additional mental disorders than people of typical IQ (Deb et al. 2001; Cooper et al. 2007). A signi®cant proportion of people with ID in the community therefore have coexisting mental health problems causing much morbidity, carer burden and health and social care service costs. Despite this situation there remains a serious lack of evidence on the effectiveness of mental health services for them.