an increasing trendP=0.065
LTBI incidence did not significantly differ by classification (Group 1: 0.8%, Group 2: 0.3%, Group 3: 1.2%, Group 4: 1.0%; P< 0.001) but showed an increasing trend with exposure frequency (No exposure: 0.7%, One exposure: 0.6%, Two exposures: 2.2%, Three or more: 3.8%; P=0.065).