Latent Tuberculosis Infection among a Large Cohort of Medical Students at a Teaching Hospital in Italy

Table 2

Proportion of positive tuberculin skin testing response stratified by the main collected variables.

Variables	TST-positive result	%	value
Gender
Male	5/560	0.9	0.9
Female	6/742	0.8
Nationality
Italian	4/1226	0.3	<0.0001
Foreign	7/76	9.2
Born in a high TB incidence country^*
No	8/1281	0.6	<0.0001
Yes	3/21	14.3
Year of attendance
First	2/219	0.9	0.6
Second	2/287	0.7
Third	0/186	0
Fourth	4/262	1.5
Fifth	1/183	0.5
Sixth	2/165	1.2
Level of training
Preclinical	4/692	0.6	0.3
Clinical	7/610	1.2
BCG immunization
No	4/1255	0.3	<0.0001
Yes	7/47	14.9
Previous professional exposure to active TB case
No	9/1221	0.7	0.09
Yes	2/63	3.2

SD: standard deviation.
TB: tuberculosis.
BCG: Bacille Calmette-Guérin.
TST: tuberculin skin testing.
High incidence: ≥20 cases per 100,000 population [12].