Yield of pulmonary tuberculosis cases by employing two screening methods in a community survey

Abstract

OBJECTIVE: To compare the yield of tuberculosis (TB) cases by two screening methods. SETTING: Two disease surveys conducted in Tiruvallur, south India. RESULTS: Of bacteriologically confirmed cases, 60% were identified by symptom inquiry alone whereas 82% were identified using chest radiography (CXR). CONCLUSION: The prevalence of TB was underestimated by both methods. The total cases in this community can be estimated by multiplying the number of identified cases by a correction factor (CF) of 1.7 when symptom inquiry alone is used or 1.2 when CXR is used. The CF may be different in other settings