Fig. 3: Development of confirmed tuberculosis among participants with differing subcategories of uncertain and stable X-ray findings, stratified by the time period of follow-up.

Cox proportional hazards models show adjusted hazard ratios for the development of confirmed tuberculosis among participants with differing subcategories of uncertain and stable chest X-ray findings. Models are adjusted for age, sex, body mass index, and prior tuberculosis. The unit of study is the individual participant; all data points represent biological replicates (n = 183,382 independent subjects across all groups). The screening time period occurred from March 1 to October 31, 2020. The total follow-up time period was defined as November 1, 2020–October 31, 2022. Referent category are persons with no abnormal X-ray findings (n = 155,833) at the baseline mass screening visit. Precise sample sizes for each subgroup are as follows: Uncertain, non-patchy lesions (n = 4002); Uncertain, patchy lesion (n = 5243); Stable, fibrous lesion (n = 9290); Stable, sclerotic lesion (n = 2920); Stable, Calcification (n = 4277). To account for any undiagnosed, early tuberculosis patients that may have been diagnosed in year 1 of follow-up, a secondary follow-up period with a one year lead-in time was analyzed. This time period began > 1 year after completion of screening and ran from November 1, 2021–October 31, 2022. Referent category are persons with no abnormal X-ray findings (n = 154,447) at the secondary follow-up period. Precise sample sizes for each subgroup are as follows: Uncertain, non-patchy lesions (n = 3819); Uncertain, patchy lesion (n = 5202); Stable, fibrous lesion (n = 9080); Stable, sclerotic lesion (n = 2857); Stable, Calcification (n = 4163).Error bars represent the 95% confidence intervals (CI).