[Epidemiology of tuberculosis in Iran [2001-08]]

The characterization of any disease have important role for the evaluation and control strategy and programming of diseases. This study was done to determine the epidemiology of Tuberculosis in Iran during 2001-08. In this descriptive cross sectional study, Annual percentage change [APC], average annual percentage change [AAPC] of Tuberculosis incidence rate, mortality of Tuberculosis, case detection rate, success percentage in Tuberculosis treatment and relapses cases during 2001-08 have been studied in Iran. Linear segmented regression model was used for analysis trend of Tuberculosis and estimate parameters. The trend of Tuberculosis smear positive [SP] incidence rate was reduced in Iran during 2001-08. Anually, 4.1% and 3.6% reduction took place in incidence rate and relapses cases, respectively. Tuberculosis mortality decreased annually by 6.8% and success in case detection increased by 2.5%. The Tuberculosis treatment though AAPC is decreasing by 0.5%. The trend of Tuberculosis are higher among women and in both sexes over 65 years of age. This study showed that trend of SP pulmonary tuberculosis and treatment success rate is decreased, but case detection was increased

[Applying segmented regression model to analysis the trend of tuberculosis incidence rate in Iran between 1964 -2008]

Study trend of observed rates changes provide valuable information for need assessment, plan, reload programs and develop indicators of each country. The main objective of this paper is to determine the changes in tuberculosis incidence rate trend in Iran by applying segmented regression model. In this study, segmented Linear Regression employed to analyze the trend of changes in pattern of Tuberculosis incidence rate during past 44 years [1964-2008] in Iran. We used least square method and permutation test and Bayesian Information Criteria to decide which of the two segment regression model and poison regression would be better. Data analyzed by Joinpoint 3.4 and SAS 9.1 software. According the permutation test, it was detected that there were two breakpoints over 1977 and 1993 years [p=0.0108]. Incidence rate of tuberculosis during the first 11 years of review had declined with annual percentage change = -10.1%, for second segment it rose upward with 4.3% increase in per year and for end segment TB incidence rate again declined with annually 4.5%. The average annual change of Tuberculosis incidence rate in Iran for at least 10 years has been estimated -4.5 percentages. The findings of this study have shown that the incidence rate of Tuberculosis decreased after 1992 that interestingly this decline seems faster than estimated by international TB control program. This indicates that preventive and treatment of Tuberculosis programs have been successful in Iran