Clinical and cost evaluation of two models of specialist intensive support teams for adults with intellectual disabilities who display behaviours that challenge: the IST-ID mixed-methods study

Angela Hassiotis, Athanasia Kouroupa, Leila Hamza, Louise Marston, Renee Romeo, Nahel Yaziji, Ian Hall, Peter E. Langdon, Ken Courtenay, Laurence Taggart, Nicola Morant, Vicky Crossey, Brynmor Lloyd-Evans

Research output: Contribution to journalArticlepeer-review


Background: Intensive support teams (ISTs) are recommended for individuals with intellectual disabilities who display behaviours that challenge. However, there is currently little evidence about the clinical and cost-effectiveness of IST models operating in England.

Aims: To investigate the clinical and cost-effectiveness of IST models.

Method: We carried out a cohort study to evaluate the clinical and cost-effectiveness of two previously identified IST models (independent and enhanced) in England. Adult participants (n = 226) from 21 ISTs (ten independent and 11 enhanced) were enrolled. The primary outcome was change in challenging behaviour between baseline and 9 months as measured by the Aberrant Behaviour Checklist-Community version 2.

Results: We found no statistically significant differences between models for the primary outcome (adjusted β = 4.27; 95% CI −6.34 to 14.87; P = 0.430) or any secondary outcomes. Quality-adjusted life-years (0.0158; 95% CI: −0.0088 to 0.0508) and costs (£3409.95; 95% CI −£9957.92 to £4039.89) of the two models were comparable.

Conclusions: The study provides evidence that both models were associated with clinical improvement for similar costs at follow-up. We recommend that the choice of service model should rest with local services. Further research should investigate the critical components of IST care to inform the development of fidelity criteria, and policy makers should consider whether roll out of such teams should be mandated.
Original languageEnglish
Article numbere116
JournalBJPsych Open
Issue number4
Early online date26 Jun 2023
Publication statusPublished - Jul 2023


  • Intellectual disability
  • cost-effectiveness
  • developmental disorders
  • intensive support
  • outcome studies

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