Epidemiologic Trend of Smear-Positive, Smear-Negative, Extra Pulmonary and Relapse of Tuberculosis in Iran (2001-2015); A Repeated Cross-Sectional Study

Background: Trend analysis is an important tool to monitor epidemiological changes of disease over time to guide resource allocation. This study aimed to study incidence trends and change-points of smear positive, smear negative, extra-pulmonary and relapse of tuberculosis (TB) in Iran from 2001 to 2015. Study design: Repeated cross-sectional study Methods: Nonlinear segmented regression was used to describe TB incidence trends; annual percent change (APC), average annual percent changes (AAPC) and change points for each disease separately. Results: Of 154930 TB cases, 49.8% were smear positive, 19.7% smear negative, 27.32% extra-pulmonary and 3.18% relapse. For all TB types, the peak of incidence was in 2001. Two change point were estimated for all TB types (P