The total site sample was 10 health facilities and 10 matched public schools from Kigali. The
locations of the health facilities were used to define informal local catchment areas.From within
each of those health care catchment areas, the nearest public school was included in the survey.
Thus, workers from the selected schools within each catchment area serve as the reference
from which we assessed the comparative risks of LTBI and TB disease among the health care
workers within the respective catchment areas. We recruited school workers as our control
group because they are socio-demographically similar to health care workers but differ with regards
to workplace exposure to TB.
We recruited all clinical and nonclinical staff from health care facilities and teachers and administrators
employed at participating schools. All HCWs and SWs must have served in the facility
for at least 6 months and be 21 years of age to be eligible. All participants provided a
written informed consent.