Cost-utility analysis of community occupational therapy in dementia (COTiD-UK) versus usual care: Results from VALID, a multi-site randomised controlled trial in the UK

BACKGROUND: A community-based occupational therapy intervention for people with mild to moderate dementia and their family carers: the Community Occupational Therapy in Dementia–UK version (COTiD-UK); and Treatment as usual (TAU) were randomly assigned to 468 pairs (each comprising a person with dementia and a family carer) in the Valuing Active Life in Dementia (VALID) randomised controlled trial (RCT). OBJECTIVES: To compare the cost-utility of the COTiD-UK intervention compared to TAU, using data from the VALID RCT. METHODS: We performed a cost-utility analysis estimating mean costs and quality adjusted life years (QALYs) per person with dementia and carer for both treatments over a 26 weeks’ time horizon based on resource use data and utility values collected in the trial. RESULTS: Taking the National Health Service and Personal Social Services perspective, including costs and benefits to the person with dementia only, measuring Health Related Quality of Life based on Dementia Quality of Life scale (DEMQOL), accounting for missing data and adjusting for baseline values, there was a significant difference in costs between COTiD-UK and TAU (mean incremental cost for COTiD-UK £784 (95% CI £233 to £1334)), but no significant difference in outcomes (mean QALYs gained 0.00664 (95% CI -0.00404, 0.01732)). The Incremental Net Monetary Benefit (INMB) for COTiD-UK versus TAU was negative at a maximum willingness to pay for a QALY of £20000 (mean -£651, 95% CI -£878 to -£424) or £30000 (mean -£585, 95% CI -£824 to -£345). Extensive sensitivity analyses confirmed the results. CONCLUSIONS: This community-based occupational therapy intervention has a very low probability of being cost-effective.