Supplementary file 1_Pre-screening village tuberculosis notification rates and the yield of interferon-gamma release assay testing in a rural health-examination campaign in Xinjiang, China.docx

Village-level regression, burden-group comparisons, and 1,000 village-cluster bootstrap resamples complemented the principal analysis.</p>Results<p>Overall, 1,006 of 3,742 participants were IGRA positive (26.88%, 95% CI 25.49–28.33%); village-specific positivity ranged from 19.13 to 39.67%. High-burden villages contributed 39.56% of positive results while accounting for 33.27% of participants. Pooled positivity was 31.97% in high-burden villages, compared with 24.51 and 24.19% in low- and medium-burden villages.

Each increase of 100 notifications per 100,000 was associated with 15.3% higher adjusted odds of positivity (OR 1.153, 95% CI 1.043–1.275; p = 0.006); the village-bootstrap estimate was similar. At village level, the corresponding increase in positivity was 2.92 percentage points (95% CI 1.18–4.67; p = 0.002). Male sex, ages 50–79 years, lower-income program category, known TB exposure, and previous TB were independently associated with positivity.</p>Conclusion<p>IGRA positivity was common among campaign participants and increased with pre-screening village notification rates.

Within the annual health-examination program, the continuous notification rate can be combined with individual risk factors to inform the scheduling of IGRA outreach and clinical assessment while maintaining access in every village. The 26.88% estimate pertains to participants and should not be interpreted as township prevalence.</p>