Sh Arsang, A Kazemnejad, F Amani,
Volume 7, Issue 3 (11 2011)
Abstract
Background & Objectives: 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.
Methods: 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 Joinpoint3.4 and SAS9.1 software.
Results: 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.
Conclusion: 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.
N Mohammadsalehi, K Holakouie Naieni , B Eshrati, A Mohammadbeigi, E Ahmadnezhad, Sh Arsangjang,
Volume 14, Issue 1 (Vol 14, No 1, 2018)
Abstract
Background and Objectives: Cholera is one of the public health ththat has received attention due to climate change and weather variables. In the current study, the trend of cholera and its epidemics was assessed in the last 50 years in Iran based on climatic variables.
Methods: In a retrospective cohort study, all cholera cases and epidemics of the disease in the country (Iran) were assessed using the registry system of the Center for Communicable Disease Control in the Ministry of Health and Medical education (MOH&ME) from 1964 to 2014. Furthermore, the incidence of cholera was evaluated in 2005-2014 by province. The temperature and rainfall data were obtained from the provincial Meteorological Organization. The correlation coefficient test and mixed-effects binomial regression model were used for data analysis.
Results: A significant positive correlation was found between cholera and rainfall (r = 0.168, P = 0.008). A one-millimeter increase in rainfall increased the incidence of cholera by 10.9% but temperature changes had no effect on cholera outbreaks. The incidence of cholera declined significantly by 14.7% each year from 2005 to 2014. The highest incidence of cholera was reported in Sistan-Baluchestan, Qom, Tehran, Kerman and Hormozgan provinces in a descending order.
Conclusion: In recent years, the the overall incidence of cholera has decreased. The occurrence of cholera is an outcome of rainfall in the previous year. Therefore, increased rainfall increases the number of cholera cases in the next year. However, temperature changes are not related to cholera outbreaks.
