Risk factors associated with tuberculin skin test positivity among university students and the use of such factors in the development of a targeted screening program

The present study evaluated the accuracy of a risk assessment questionnaire (RAQ) for identifying candidates for tuberculin testing. A 33-question RAQ was administered to students before they underwent tuberculin screening at Virginia Commonwealth University (Richmond). Test operating characteristics for the complete and abbreviated RAQs compared to tuberculin skin test (TST) results were determined. Of 5382 students screened, 125 (2.3%) had a positive TST result; 113 (90.4%) of these 125 students had greater than or equal to1 affirmative response on the RAQ (i.e., a "positive RAQ"). The prevalence of TST positivity among students not born in the United States was 33.2-fold higher than that among students born in the United States. A 2-question RAQ had a sensitivity of 81.6%, a specificity of 91.0%, and positive and negative predictive values of 17.7% and 99.5%, respectively. Risk assessment can be an accurate means of identifying candidates for tuberculin screening.