Table 1 Relevant terminology

• Stages in the care cascade are defined as the steps required to progress from the diagnosis of an infection or disease to treatment for viral suppression or disease cure [14, 15]. In the context of this study, the stages cover: (1) community-based testing, (2) linkage to care, and/or (3) adherence to treatment for HBV and HCV, HIV, and TB. The continuum of care aims at maintaining continuity of engagement of individuals from testing, linkage to care, and adherence to treatment and across multiple care and treatment facilities.

• Interventions are efforts that aim to improve one or more stages in the care cascade (case management, contingency management, cooperation, decentralisation of services, directly observed therapy [DOT], integrated services, opioid agonist treatment [OAT], peers, telemedicine). The definitions of the interventions follow those used in the preceding systematic review by Schwarz et al. [9].

• Models of Good Practice (MoGP) were defined as an intervention or a package of interventions that has shown evidence of effectiveness in particular settings and is likely to be replicable.