Digital approaches to reducing TB treatment loss to follow-up.

Poor adherence to TB treatment leads to adverse clinical outcomes. A range of digital technologies to support adherence have been developed and the COVID-19 pandemic considerably accelerated the implementation of digital interventions. Here, we review the current evidence on digital adherence support tools and update the findings of a previous review, with evidence published from 2018 to date. Interventional and observational studies, as well as primary and secondary analyses were included, and we summarised available evidence on effectiveness, cost-effectiveness and acceptability. The studies were heterogenous and varied in outcome measures and approaches used. Overall, our findings show that digital approaches, such as digital pillboxes and asynchronous video-observed treatment, are acceptable and have the potential to improve adherence and be cost-effective over time if implemented at scale. Digital tools should be part of multiple strategies to support adherence. Further research to integrate behavioural data on reasons for non-adherence will help to determine how to best implement these technologies in different settings.