Iranian Journal of Epidemiology
Year:2017 | Volume:12 | Issue:4|Papers Count:11

Background and Objectives: By identifying the causes of death, interventions can be designed and implemented to reduce the risk factors of different diseases. The aim of this study is to determine the trend of ten leading causes of death in the Islamic Republic of Iran in 2011.Methods: The study population comprised all deaths recorded in the death registration system of the Ministry of Health and Medical Education (MOHME) from 2006 to 2011. The data related to causes of death reviewed and modified in terms of quality, underreporting of deaths, and garbage codes using the Global Burden of Disease study methods. Finally, the data were analyzed by sex and age groups.Results: The leading causes of death were cardiovascular diseases (46.12%), cancers and tumors (13.63%) and unintentional injuries (11.55%) in 2011. The 10 leading causes of death in the general population were myocardial infarction, stroke, transportation-related accidents; blood pressure induced heart disease, other cardiovascular diseases, diabetes, chronic pulmonary and bronchial diseases, gastric cancer, other heart diseases and renal failure.Conclusion: Deaths from non-communicable diseases still account for a large proportion of total deaths. According to the Heath System Reform Plan in Iran and the need for new interventions, it is very important to register the exact causes of death to design service packages and also evaluate the success rate of ongoing interventions.

Background and Objectives: Brucellosis in livestock has led to a significant reduction in the economic capital in Iran. Estimation of the economic losses due to this disease helps to highlight the importance of the disease and makes it easy to justify brucellosis control programs.Methods: Estimation was done based on the data received from the Iran Veterinary Organization and statistics book of the Iranian Ministry of Agriculture. Economic Loss was estimated assuming the equality of the incidence of the disease in total livestock population with its incidence in tested livestock. The direct costs of culled brucella positive animals, reduced milk production, reduced weight of animal, abortion, and reduced fertility were calculated based on the price of the animal or the product in each year. Due to inflation, the costs were adjusted using the discount rate. Therefore, the losses were compared in each year.Results: The maximum loss due to brucellosis in the studied period occurred in 2014. Comparison of the losses due to bovine and ovine brucellosis showed that the total economic loss in the sheep and goat population was 5.53 times greater than the loss in the cattle population. Estimation of total economic loss in 12 years of the study was 8,129,116 million IRR (1 USD≅35000 IRR).Conclusion: More serious attention should be paid to animal brucellosis from both health and economic points of view. Prevention from massive economic losses and human brucellosis control and eradication will not be possible without controlling the disease in the animal population.

Background and Objectives: The Haemophilus influenzae (Hib) conjugate vaccine (HibCV) using a pentavalent formulation was introduced to the Iranian routine immunization program from November 2014. Iran is preparing to include Pneumococcal conjugate vaccines (PCV), as well. Measuring and monitoring the impact of HibCV and PCV are necessary to provide evidence for introduction and sustained administration of this vaccine.Methods: We addressed the possibility of implementing the "3-tiered approach to IB VPD surveillance" as proposed by the World Health Organization using a feasibility study. Expert opinions were asked to address published literature regarding the study design and methods of measuring the impact of newly introduced vaccines.Results: There are different methods and study designs to measure the impact of new vaccines, including population based active surveillance systems and vaccine effectiveness studies. The results of the feasibility study and expert opinions highlighted the superiority of a sentinel hospital-based surveillance system in Iran.Conclusion: It is necessary to conduct some systematic reviews and meta-analyses to provide evidence for the trend of Hib and Streptococcus pneumonia related diseases, i.e. invasive bacterial diseases including meningitis, pneumonia, and sepsis. To monitor indirect effects of the PCV vaccine, implementing periodic surveys on the prevalence of nasopharyngeal carriers are recommended.

Background and Objectives: Iran is classically located in the Palearctic zoogeographic zone, but southern pasts of Iran are drastically different from other parts in terms of fauna and flora. Nowadays, considering the technological advances and the ability to locate the zone border using aerial photos, and the need for comparing the prevalence of the diseases in different locations, it is necessary to identify the border of tropicallike zones as detailed as possible.Methods: The shapefile of the political classification of Iran was used as the base map and metrological and terrestrial data were obtained from Iran Climatologic Research Center and literature review. Data were arranged in the Geospatial Information System and after geostatistical analysis, a raster map was generated and a probability map for all tropical conditions was calculated and generated as a raster map. Tropical areas were proposed in two layers.Results: According to our study, between 113 to 125 districts from 8 provinces were located in tropical-like zones. Three of these districts had typical criteria of the Indo-Malayan zone and others resembled the Afrotropical zone. The table of the districts located in the tropical-like zones and the shapefile of these areas are available on the website of Iranian Journal of Epidemiology.Conclusion: Although Iran in located in the Palearctic zoogeographic area, there are some southern areas which resemble tropical regions and accurate definition of borders is a basic essential need for geo-referenced epidemiology and determining the disease pattern. This study provided a preliminary map for this field of study.

Background and Objectives: Cardiac diseases are a major cause of death in Iran. The number of deaths from cardiac diseases can be reduced through controlling air pollution. The aim of this study was to determine the relationship between increased air pollution and mortality from respiratory and cardiac diseases in Tehran.Methods: The average daily concentrations of five pollutants, including carbon monoxide (CO), nitrogen dioxide (NO2), ozone (O3), sulfur dioxide (SO2), and particulate matter less than 10 microns (PM10) were collected from 8 stations in Tehran, Iran. Then, their effects on the number of daily deaths due to cardiovascular and respiratory diseases were calculated using time series and Poisson GLARMA model (generalized linear autoregressive moving average). The climatic elements such as mean, maximum, and minimum temperature and daily humidity were considered as confounding factors.Results: After adjustment for potential confounding variables of the final model of the pollutants, the mean daily ozone level (P=0.02) and particulate matters less than 10 microns (P<0.001) had a significant correlation with the number of daily deaths.Conclusion: According to the results of this study that addressed the relationship between air pollutants and death using new statistical methods, it is necessary to take more effective measures to control ozone and particulate matters less than 10 microns to reduce the mortality of heart and respiratory diseases in Tehran.

Background and Objectives: Food is one of the major needs of the humans that is defined in the context of food security. The objective of this study was to find the relationship between food insecurity and stunting combined with obesity and overweight in children aged 7-11 years old in Zabol.Methods: This study had two phases. In the first phase (cross-sectional), 3443 students aged 7-11 years old were selected with stratified-cluster sampling. In the second phase, all of the children with stunting and obesity or overweight based on the CDC growth chart comprised the case group and 112 students with normal height and weight based on the CDC growth chart comprised the control group. The case and control groups were matched in terms of age, sex, and school. The food security USDA questionnaire that consists of 18 items was completed through interview with mothers to evaluate the family food security.Results: The prevalence of stunting, obesity, and overweight was 17.95%, 4.56%, and 10.98% respectively and the prevalence of stunting combined with obesity and overweight was 1.71% in the first phase of the study. There was a significant relationship between food insecurity and stunting combined with obesity and overweight. Food insecurity had a significant relationship with low economic status, living in rented homes, labor job and unemployment of the household head, and low education level of the household head in the case group.Conclusion: Because of the significant relationship between food insecurity and stunting combined with obesity and overweight, it is necessary to design interventional programs to prevent or reduce food insecurity.

Background and Objectives: When computing a confidence interval for a binomial proportion p, one must choose an exact interval that has a coverage probability of at least 1-α for all values of p. In this study, we compared the confidence intervals of Clopper-Pearson, Wald, Wilson, and double ArcSin transformation in terms of maintaining a constant nominal type I error.Methods: Simulations were used to compare four methods of estimating a confidence interval, including the Clopper-Pearson, Wald, Wilson, and double ArcSic. The data were generated from the binomial and Poison distribution with parameters p, n and m=np, 1000 were produced. Type I error of each method was calculated per simulation. The above methods were used to estimate confidence intervals in a meta-analysis study.Results: The results of the simulation study showed that double ArcSin keep confidence interval at [0,1], but for some proportion has high type I error or low coverage probability. The Clopper-Pearson interval guarantees that the coverage probability is always equal to or above the nominal confidence level for any fixed p.Conclusion: This study showed that confidence interval estimations the Clopper-Pearson than other methods of calculating the type I error fixed and smaller.

Calculation of Cronbach's Alpha which measures the internal reliability of a tool is easy, but misuse and misconception are widely observed. Common misunderstandings of the Cronbach's Alpha include inability to differentiate between being one-dimensional and consistency, and between raw and standardized alpha. Violations of the assumptions of alpha could also cause an increase or decrease in the calculated alpha. In this paper, we showed that a very large but confusing alpha coefficient could be obtained, particularly when the one-dimensional theory is violated. Also, the use of standard error measurement as an index of the reliability has been presented. Finally, the generalizability of alpha coefficient is also discussed.