Evaluating specialist intensive support teams for adults with intellectual disabilities who display behaviours that challenge: The IST-ID mixed methods study

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. Methods 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 (10 independent and 11 enhanced) were enrolled. The primary outcome was change in challenging behaviour between baseline and 9 months measured by the Aberrant Behaviour Checklist-Community 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. Study registration number [ClinicalTrials.gov][1] [NCT03586375][2]; IRAS 239820; National Institute for Health Research (NIHR) Central Portfolio Management System (CPMS) 38554. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This project is funded by The National Institute for Health Research (NIHR) Health Services and Delivery Research (HS&DR) programme (NIHR Ref. No 16/01/24). The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study was performed in accordance with the Declaration of Helsinki. Ethical approval was provided by the London Bromley Research Ethics Committee (18/LO/0890). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes Anonymised data included in the survey are available from the authors on request and subject to internal review of proposals. [1]: http://ClinicalTrials.gov [2]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT03586375&atom=%2Fmedrxiv%2Fearly%2F2022%2F05%2F16%2F2022.05.16.22275150.atom