Adaptive bandit algorithms increase efficiency of mobile tuberculosis screening programs

Community-based tuberculosis screening using mobile X-ray units can effectively increase case detection rates by reducing barriers to accessing services. This study evaluated the multi-armed bandit (MAB) framework, a machine learning approach, for optimizing mobile screening locations. Using simulations, we compared two MAB algorithms-Exp3 and LinUCB-with strategies based on historical case rates and random placement. The MAB algorithms continually updated site selection based on observed screening yields, and LinUCB additionally incorporated local socioeconomic indicators associated with tuberculosis rates. Over three years, assuming two mobile units serving 95 sites in Lima, Peru, 1,000 simulations demonstrated the MAB algorithms significantly reduced the average number of screenings needed to detect one individual with tuberculosis: 112 (standard deviation [SD]: 10) for Exp3 and 79 (SD: 12) for LinUCB, versus 152 (SD: 11) for random placement and 143 (SD: 11) for historic case-rate-driven placement. LinUCB performed best, achieving a 20% increase in detection efficiency by week 16 and 50% by week 40 compared to case-rate-driven placement. Overall, both MAB algorithms improved tuberculosis screening yields, emphasizing the value of data-driven approaches for optimizing mobile screening interventions. Incorporating adaptive models into screening programs may enhance targeting efficiency and offers a promising direction for policymakers and implementers seeking to optimize resource allocation in high-burden setting.