Iranian Journal of Epidemiology
Year:2016 | Volume:12 | Issue:2|Papers Count:12

Background and Objectives: Cutaneous leishmaniasis (CL) is a public health problem in Iran and Kerman Province which is expanding to new foci. This study was conducted to estimate the incidence of CL by a simple and cost-effective method in a major focus of CL in the city of Kerman, southeastern Iran.Methods: A combination of two longitudinal and cross-sectional studies was performed. First, the frequency of referred patients to the CL treatment clinic in 2009-2014 was assessed. Then, four highly infected zones consisting of 800 households in the city were selected. In addition, the relative proportions of referred and non-referred subjects were assessed. Eventually, the incidence of CL was calculated by dividing the number of CL cases over the total at risk population for the corresponding period (2009-2014).Results: The mean annual incidence was 175 per 100000 (943 patients) in the city of Kerman, while it was 500 per 100000 people (0.5%) in the new foci. The highest CL infection was observed among the <25-year-old individuals but there was no significant difference between the sexes.Conclusion: The incidence rate probably increased significantly following the 2003 Bam earthquake because of the migration of CL patients to southern, eastern, and northeastern areas of the city of Kerman. Since only 50% of the cases were passively referred to the CL treatment clinic, health authorities should actively detect CL cases by house-to-house visit for effective treatment strategies.

Background and Objectives: One of the main concerns of heart specialists is the occurrence of restenosis after coronary angioplasty which can lead to coronary artery bypass graft, myocardial infarction, and death. The present study was conducted to investigate the factors affecting the frequency of restenosis during four years in patients of Zanjan.Methods: In the present retrospective cohort study, all the patients who underwent angioplasty in Ayatollah Musavi Hospital of Zanjan from April of 2009 to June of 2011 were examined in terms of the frequency of restenosis. According to the patients’ medical records, all the demographic and clinical data of the patients were collected. Since the dependent variable was count in nature and the data were over-dispersed, negative binomial regression was used for modeling.Results: The incidence of at least one restenosis during four years after angioplasty was calculated to be 43%. According to the negative binomial regression model, the ratio of restenosis in patients suffering from diabetes, unstable angina, chronic kidney disease, and myocardial infarction was 32%, 44%, 66%, and 30% more than other patients, respectively (P<0.05).Conclusion: In the present study, the effective factors of restenosis were recognized as diabetes, unstable angina, chronic kidney disease, and history of myocardial infarction; hence, assessment and periodic follow-up of these patients are strongly recommended.

Background and Objectives: Infertility is one of the most important crises in the lives of couples, which create psychological consequences beside the economic, social and individual problems,. Decreased sexual satisfaction is one of the consequences of infertility. Given the importance of this concept in the life of infertile couples, a tool to measure the sexual satisfaction of this group of people is necessary. Thus, the study aimed to assess the psychometric properties of the Persian version of the LSSQ in Iranian infertile couples in 2013.Methods: In this methodological study, 150 Iranian infertile couples completed the 25-item Larson's sexual satisfaction questionnaire in Qazvin. Its reliability was determined by the calculation of Cronbach's alpha coefficient. Exploratory and confirmatory factor analyses were done by SPSS-AMOS22.Results: The internal consistency of the sexual satisfaction questions estimated with Cronbach's alpha was more than 0.7. Exploratory factor analysis was used to evaluate the construct validity of the questionnaire which showed 4 factors (desire to have sexual relations, sexual attitude, quality of sex life, and sexual compatibility) with Eigen values greater than one. Four latent factors explained 53.21% of the total variance. Confirmatory factor analysis confirmed the final model of the construct of the questionnaire.Conclusion: The results of study showed that the Persian version of LSSQ has a suitable validity and reliability in the Iranian infertile couples. Factor analysis confirmed that the LSSQ had a multi-dimensional structure.

Background and Objectives: Salmonella contamination of broiler breeder farms is of great importance regarding transmission of the bacteria through the production chain of poultry meat. The aim of this study was to determine the prevalence and management related factors of Salmonella contamination in broiler breeder flocks in Iran.Methods: This cross sectional study was carried out between 2013 and 2014 in 23 provinces of Iran. Fecal samples were obtained from 139 broiler breeder farms and were subjected to standard bacteriological tests for Salmonella isolation. The serogroups of isolated Salmonella were determined using standard serological tests. Relevant information of sampled holdings was acquired from the GIS system and used for risk factor detection.Results: The prevalence of Salmonella contamination in broiler breeder holdings was 7.9% and the more positive samples were from Tehran and Fars provinces. The flock age (P=0.019) and the number of poultry houses in the farm (P=0.037) were major risk factors of Salmonella contamination in broiler breeder farms.Conclusion: This investigation showed that the prevalence of Salmonella contamination in broiler breeder farms was relatively high. It is necessary to establish an appropriate program for controlling Salmonella contamination in broiler breeder farms. Regular sampling for early detection of contaminated farms would be very important in this case. Sampling from old flocks should be the first priority.

Background and Objectives: Syndromic surveillance systems are used to early detection of outbreaks. The purpose of this study was to determine the feasibility of clinical and non-clinical data sources used in influenza syndromic surveillance in Zanjan.Methods: In this time series study, clinical and non-clinical data related to influenza like illness (ILI) as a potential data source of syndromic surveillance systems, including the number of missed school days collected from 12 schools and the data of over the counter (OTC) drug sale obtained from 15 pharmacies selected randomly in Zanjan during 2014 were used. We used the line plot and moving average chart to explore trends and detect potential explainable patterns of data sources. The autocorrelation function and cross correlation function besides corresponding graphs were used to assess the feasibility of school absenteeism and OTC sale in timely detection of influenza outbreaks.Results: Line plots indicated the presence of explainable patterns and the effect of the day of the week. The cross correlation value was 0.5 and cross correlogram revealed the similarity of both data sources in this study.Conclusion: Our findings indicated the feasibility of influenza data sources, including school absenteeism and OTC, as potential data sources of syndromic surveillance systems.

Background and Objectives: Breast cancer is one of the most common malignancies in women which accounts for the highest number of deaths after lung cancer. The aim of the current study was to compare the logistic regression and classification tree models in determining the risk factors and prediction of breast cancer.Methods: We used from the data of a case-control study conducted on 303 patients with breast cancer and 303 controls. In the first step, we included 16 potential risk factors of breast cancer in both the logistic regression and classification tree models. Then, the area under the ROC curve (AUC), sensitivity, and specificity indexes were used for comparing these models.Results: From 16 variables included in the models, 5 variables were statistically significant in both models. Sensitivity, specificity, and AUC was 71%, 69%, and 74.7% for the logistic regression and 63.3%, 68.8%, and 71.1% for the classification tree, respectively.Conclusion: The obtained results suggest that the classification tree has more power for separating patients from healthy people. Menopausal status, number of breast cancer cases in the family, and maternal age at the first live birth were significant indicators in both models.

Background and Objectives: Hirschsprung's disease is one of the congenital movement disorders of the bowel whose accurate and timely diagnosis in childhood is important. The disease occurs due to lack of ganglion cells in the distal part of the digestive system and leads to functional obstruction of the colon. Recently, by the frozen section method, the diagnosis and treatment of the disease is possible through one-stage surgery with fewer complications and lower costs without the need for early colostomy. The aim of this study was to evaluate the validity of frozen section in Hirschsprung's disease.Methods: this retrospective study was done on 406 frozen section results obtained from patients admitted to Mofid Hospital during 1389-90. We evaluated the frequency of “positive” and “negative” samples and compared them with the results of the permanent section. Moreover, the validity, sensitivity, specificity, and positive and negative predictive value of frozen section were calculated.Results: After examining 406 frozen section samples and comparison with the results of permanent section, the results were consistent for both methods in 369 cases (90.89%) while the results were inconsistent in 37 cases (9.11%). Frozen section showed 7 (1.7%) false negative and 30 false positive (7.3%) cases. The sensitivity, specificity, positive predictive value, and negative predictive value of frozen section was 94.44%, 89.29%, 79.87%, and 97.28%, respectively.Conclusion: Frozen section is a good tool for screening and diagnosis. Its power to rule out the disease is rather more than its power to confirm its presence. so it is capable of ruling out the disease in 97% and confirming its presence in 80% of the cases.

Sampling hidden populations is challenging due to the lack of convenience statistical frames. Since most populations exposed to special diseases are hidden and hard to reach, sampling methods that produce representative and efficient samples from the populations have become a study subject for researches all over the world. Because of the unknown probability of selecting samples in conventional sampling methods and also invalidity of generalizing the results of non-probability sampling methods to the statistical population, the necessity of introducing probability chain-referral sampling methods, such as the respondent driven sampling method becomes imperative. In this article, besides introducing the respondent driven sampling method, some of the advantages of this method as relative decrease of the bias of estimates, declining the non-response rate by paying incentives and allocating weights proportional to reciprocal of the social network size of respondents to produce unbiased estimates are described. Moreover, some disadvantages of this method such as lack of producing differential samples by selecting similar seeds, lack of reaching more efficient method than snowball sampling by implementing this method improperly and lack of achieving to equilibrium by existing weak social networks among members of interested population are stated. Another aim of this article is to compare sampling methods of hidden population with the respondent driven sampling method which are the results of implementing this method in different surveys and existing simulations.