Hearing dogs for people with severe and profound hearing loss: a wait-list design randomised controlled trial investigating their effectiveness and cost-effectiveness

BACKGROUND: Hearing loss increases the risk of poor outcomes across a range of life domains. Where hearing loss is severe or profound, audiological interventions and rehabilitation have limited impact. Hearing dogs offer an alternative, or additional, intervention. They live permanently with recipients, providing sound support and companionship. METHODS: A single-centre, randomised controlled trial (RCT) evaluated the impacts of a hearing dog on mental well-being, anxiety, depression, problems associated with hearing loss (responding to sounds, fearfulness/social isolation), and perceived dependency on others. Participants were applicants to the UK charity ‘Hearing Dogs for Deaf People’. Eligibility criteria were as follows: first-time applicant; applying for a hearing dog (as opposed to other support provided by the charity). Participants were randomised 1:1 to the following: receive a hearing dog sooner than usual [HD], or within the usual application timeframe (wait-list [WL] comparator). The primary outcome was mental well-being (Short Warwick-Edinburgh Mental Well-Being Scale) 6 months (T1) after HD received a hearing dog. The cost-effectiveness analysis took a health and social care perspective. RESULTS: In total, 165 participants were randomised (HD n = 83, WL n = 82). A total of 112 (67.9%) were included in the primary analysis (HD n = 55, WL n = 57). At T1, mental well-being was significantly higher in the HD arm (adjusted mean difference 2.53, 95% CI 1.27 to 3.79, p < 0.001). Significant improvements in anxiety, depression, functioning, fearfulness/social isolation, and perceived dependency, favouring the HD arm, were also observed. On average, HD participants had used fewer statutory health and social care resources. In a scenario whereby costs of provision were borne by the public sector, hearing dogs do not appear to be value for money. If the public sector made a partial contribution, it is possible that hearing dogs would be cost-effective from a public sector perspective. CONCLUSIONS: Hearing dogs appear to benefit recipients across a number of life domains, at least in the short term. Within the current funding model (costs entirely borne by the charity), hearing dogs are cost-effective from the public sector perspective. Whilst it would not be cost-effective to fully fund the provision of hearing dogs by the public sector, a partial contribution could be explored. TRIAL REGISTRATION: The trial was retrospectively registered with the International Standard Randomised Controlled Trial Number (ISRCTN) registry on 28.1.2019: ISRCTN36452009. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13063-021-05607-9.