Scale-up of 99DOTS for TB treatment supervision: an interrupted time series analysis

<sec><title>BACKGROUND</title>Digital adherence technologies such as 99DOTS are being scaled-up for TB treatment despite limited evidence of their effectiveness and concerns about accessibility. We evaluated the reach and effectiveness of 99DOTS during its scale-up in Uganda.</sec><sec><title>METHODS</title>We included all adults initiating drug-susceptible pulmonary TB treatment between August 2019 to June 2021 at 12 99DOTS-naïve health facilities (n = 3,526). Using an interrupted time series design, we compared the proportion with treatment success (primary outcome) and enrolled on 99DOTS in the 9 months before and 12 months after implementing an 'enhanced 99DOTS' intervention. This included providing low-cost phones to people with TB when needed, task shifting monitoring and support to community health workers, and automated task lists. Treatment data were derived from routine TB treatment registers.</sec><sec><title>RESULTS</title>The proportion enrolled on 99DOTS post-intervention was high (87.2%) and had a slight upward trend (proportion ratio 1.01, 95% CI 1.00-1.01). Treatment completion remained similar across periods (89.8% post-intervention vs. 87.1% pre-intervention). There was no immediate level or slope change in treatment success following the intervention.</sec><sec><title>CONCLUSIONS</title>With appropriate implementation supports, 99DOTS can have high uptake without negatively impacting treatment outcomes. Equity in access should be prioritized during implementation.</sec>.