Where is the evidence? The use of routinely-collected patient data to retain adults on antiretroviral treatment in low and middle income countries-a state of the evidence review.

Retention rates in antiretroviral treatment (ART) in low- and middle-income countries are suboptimal for meeting global "90-90-90" treatment targets. Interventions using routinely collected patient data to follow up with ART defaulters is recommended to improve retention; yet, little is documented on how these data are used in practice. This state of the evidence review summarizes how facilities and programmes use patient data to retain adults on ART in low- and middle-income countries, and what effect, if any, these interventions have on retention. The authors searched peer-reviewed and grey literature in PubMed, POPLINE, OVID, Google Scholar, and select webpages; screened publications for relevance; and applied eligibility criteria to select articles for inclusion. Over 4,000 records were found, of which 19 were eligible. Interventions assessed within the studies were sorted into three categories: patient tracing (18), data reviews (3), and improved data capture systems (9). Nine studies demonstrated increased retention or reduced lost to follow-up; however, the quality of evidence was weak. We recommend that future research investigates how various combinations of these interventions are being implemented and their effectiveness on ART retention across diverse country contexts, taking into account cultural, social and economic barriers and differences in countries' HIV epidemics and health information systems.