Background Aggressive behaviour has been identified as a significant problem amongst people with intellectual disabilities living in institutional settings. Anger is a key activator of aggressive behaviour, as well as being an important element of clinical distress related to adverse life experiences. There is some evidence for the value of cognitive–behavioural treatments for anger problems with people having intellectual disabilities. No controlled studies of anger treatment involving intellectually disabled offenders living in secure settings have been conducted to date. A pilot study of an elaborated anger treatment protocol for this client population was undertaken, comparing the specialised anger treatment with routine care.
Methods Detained men with intellectual disabilities and histories of offending were allocated to specially modified cognitive–behavioural anger treatment (n = 9) or to routine care waiting‐list control (n = 10) conditions. Eighteen sessions of individual treatment were delivered over a period of 12 weeks. Treatment outcome was evaluated by participants' self‐report of anger intensity to an inventory of provocations and by staff‐ratings of the anger attributes of participants' ward behaviour.
Results Participants' reported anger intensity was significantly lower following the anger treatment, compared to the routine care wait‐list condition. There were largely no treatment condition effects in staff‐rated anger. Limited evidence for the effectiveness of anger treatment was provided by the staff ratings of participant behaviour post‐treatment.
Conclusions Detained offenders with intellectual disabilities can benefit from intensive individual cognitive–behavioural anger treatment. Further research is required to examine the mechanisms for change and their sustainability.