Table 2.

Potential geographic scales or population focuses of interest for the care cascade research agenda.

Geographic scale or population of interest	Potential research approaches	Limitations of the research approaches when applied in a given geographic scale or population
National TB programs / country-level studies	• Nationally-representative cohort studies to identify predictors of poor care cascade outcomes • Systematic mapping of populations without access to TB services • Assessing reasons individuals with active TB have not sought care in large-scale TB prevalence surveys	• National service mapping may identify major service gaps but miss barriers to health facility accessibility for local subpopulations • Reasons for not seeking care or dropping out of care by may vary for sub-populations in local contexts
Key high-risk populations (e.g., people living with HIV, people who inject drugs, slum residents, tribal populations, migrants, refugees, miners, individuals with silicosis, healthcare workers)	• Cohort studies to identify predictors of poor care cascade outcomes by screening and follow-up of affected individuals at specific sites (e.g., HIV clinics, opioid agonist therapy centers, etc.) or using unique sampling methods (e.g., respondent-driven sampling) • Qualitative studies may provide rich information that is generalizable to others in the affected sub-population	• Findings in a given high-risk population may have limited generalizability outside of that sub-population
Local city or district TB programs, hospitals, or clinics	• Cohort and qualitative studies to understand reasons for poor care cascade outcomes	• Findings may directly inform local changes in care delivery but may have limited generalizability