Aims To determine whether the provision of contingencymanagement using financial incentives to improve hepatitis B vaccine completion in people who inject drugs entering community treatment represents a cost-effective use of healthcare resources. Design A probabilistic cost-effectiveness analysis was conducted, using a decision-tree to estimate the short-term clinical and health-care cost impact of the vaccination strategies, followed by a Markov process to evaluate the long-term clinical consequences and costs associated with hepatitis B infection. Settings and participants Data on attendance to vaccination from a UK cluster randomized trial. Intervention Two contingency management options were examined in the trial: fixed versus escalating schedule financial incentives. Measurement Life-time health-care costs and quality-adjusted life years discounted at 3.5% annually; incremental cost-effectiveness ratios. Findings The resulting estimate for the incremental life-time health-care cost of the contingency management strategy versus usual care was £21.86 [95% confidence interval (CI) = –£12.20 to 39.86] per person offered the incentive. For 1000 people offered the incentive, the incremental reduction in numbers of hepatitis B infections avoided over their lifetime was estimated at 19 (95% CI = 8–30). The probabilistic incremental cost per quality adjusted life-year gained of the contingency management programmewas estimated to be £6738 (95% CI = £6297–7172),with an 89% probability of being considered cost-effective at a threshold of £20 000 per quality-adjusted life years gained (97.60% at £30 000). Conclusions Using financial incentives to increase hepatitis B vaccination completion in people who inject drugs could be a cost-effective use of health-care resources in the UK as long as the incidence remains above 1.2%.
Bibliographical noteFunding Information:
J.S. has contributed to UK guidelines, which include consideration of the potential role of contingency management in the management of opiate addiction (NICE, 2007; chaired by J.S.), and J.S. also chaired the broader-scope pan-UK working group preparing the 2007 Orange Guidelines for the UK Departments of Health, providing guidance on management and treatment of drug dependence and misuse, including guidance on possible inclusion of contingency management and is also currently chairing the new Expert Group updating these Guidelines for the four UK Departments of Health. J.S. and J.S.’s institution have received support and funding from the Department of Health (England) and National Treatment Agency (England), and J.S. and J.S.’s institution have provided funded consultancy advice on possible novel addiction treatments, products and formulations to a range of pharmaceutical companies, but these do not have any connection to the intervention being investigated nor the analyses in this paper. J.S.’s employer (King’s College London) has registered intellectual property on a novel buccal naloxone with which J.S. is involved, and J.S. has been named in a patent registration by a pharmaceutical company as inventor of a potential novel concentrated nasal spray, but these do not have any connection to the work being reported in this paper. A fuller account of J.S.’s interests is on his personal web-page of the Addictions Department at http://www.kcl.ac.uk/ioppn/ depts/addictions/people/hod.aspx. J.S. is supported by the National Institute for Health Research (NIHR) Biomedical Research Centre for Mental Health at South London and Maudsley NHS Foundation Trust and King’s College London.
This paper presents independent research funded by the National Institute for Health Research (NIHR) under its Programme Grants for Applied Research Programme (Grant Reference no. RP-PG-0707-10 149). The views expressed are those of the authors and not necessarily those of the NHS, the NIHR, Public Health England or the Department of Health. J.M.H. and J.S. are supported in part by the NIHR Biomedical Research Centre for Mental Health at South London and Maudsley NHS Foundation Trust and King’s College London. The trial was supported by the Mental Health Research Network.
- Contingency management
- Methadone maintenance program
- Viral hepatitis