Interventions to Increase Hepatitis B Testing Uptake Amongst Detained Populations: A Systematic Review.

People who have been detained have a higher prevalence of hepatitis B virus (HBV) than the general population, yet testing uptake remains limited. Improving testing uptake in high-risk settings is essential to the World Health Organization 2030 elimination target. This systematic review examines interventions aimed at increasing hepatitis B testing uptake in prison. MEDLINE, EMBASE, CENTRAL and CINAHL were searched from January 2000 to April 2025. Quantitative interventional studies were included. Quality appraisal was conducted using the JBI critical appraisal tool. A random effects meta-analysis with Freeman-Tukey transformation estimated testing uptake. Subgroup analysis explored heterogeneity by sex, geographical region and the screening approach. Sixteen papers (15 studies) were included. Eleven were post-interventional quasi-experimental studies. Nine were conducted in Europe. The pooled testing uptake was 64% (95% CI 46%-80%; I2 = 98%). Opt-in interventions were associated with a higher testing uptake (77%, 95% CI 59%-91%), in comparison to opt-out testing uptake (33%, 95% CI 17%-52%; p < 0.001), although opt-in screening had enhanced characteristics such as counselling, peer education and culturally tailored approaches. HBV prevalence amongst institutions ranged between 0% and 11.4%. Only one study reports costs. Opt-in programmes were associated with a higher testing uptake in comparison to opt-out programmes, which may reflect the underlying programme characteristics rather than the screening approach alone. Evidence on cost-effectiveness is limited. Most studies were heterogeneous and conducted in high-income countries. Further robust studies are needed to evaluate enhanced screening approaches to determine the most effective and scalable screening programme.