Iranian Journal of

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Background & Objectives: Tuberculosis (TB) is one of the major infectious diseases in Iran and has pulmonary and extra-pulmonary manifestations. Considering the differences in the distribution of the cases across different regions, we decided to study the geographical distribution, epidemiologic characteristics, and disease pattern in Lorestan.

 Methods: This ecologic (descriptive analytical) survey was done in Lorestan between 2002 and 2008. The data was collected from the Health Department of Lorestan University of Medical Sciences and included the history of 1481 patients suffering from TB. The study variables were sex, disease type, residential location, age, and year. The data were analyzed using statistical package SAS 9.2 and descriptive and inferential statistics were applied.

Results: From 1481 registered patients 58.4% were male and 41.6% were female among which 68.74% and 29.98% lived in urban and rural areas and 1.28% were nomads. The mean age of the patients was 41.87. The highest and lowest incidence rates were observed in Khoram Abad (19.38 per 100000) and Azna (7.04 per 100000), respectively. Using Poisson regression, it was observed that the effects of age structure and residency on the incidence rate were significant.

Conclusion: The percentage of nomads was identified as the most important demographic factor in the incidence rate of TB in Lorestan. Allocation of better resources and appropriate training can be effective in controlling and preventing the disease.

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Background and Objectives: Academic failure is of paramount importance for medical students because it might lead to a decline in scientific level of the community of physicians in the future. This study was conducted to investigate the predictors of academic failure in medical students of Lorestan University of Medical Sciences using classification tree. 
 
Methods: In this cohort study, academic records of all medical students of Lorestan University of Medical Sciences during the academic years of 1999-2008 were selected by census and were followed up until September 2016. Academic failure was defined as having at least one of the components of appropriate grade point average, prolonged graduation, academic probation, dropout, expulsion, and any failure in ccomprehensive exams and the CART classification tree was adopted using the SPSS 22 software to predict it.
 
Results: The cumulative incidence of academic failure was 26.4% and the most prevalent components were prolonged graduation (21.7%) and academic probation (15.0%). The probability of academic failure was 0.449 in subjects taking guest courses, 0.220 in subjects with no history of guest courses admitted to courses with less than 40 students and admission quotas of zone 1 or 3, and 0.456 in subjects with no history of guest courses admitted to courses with more than 40 students and males.
 
Conclusion: With respect to identifying the predictors of academic failure, it is suggested that these students be referred to consulting centers of the university or educational supervisors’ moreover, the regulations of taking guest courses in other universities should be revised.

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Background and Objectives: Suicide is one of the psychosocial problems in Lorestan Province due to its socio-cultural and economic structure. The aim of this study was to investigate the effect of age group, time period, and birth cohort on the suicide incidence in Lorestan Province during the 2006-2015.
 
Methods: In this study, to overcome the identifiability problem, the Carstensen approach and natural cubic smoothing character were used in age-period-cohort models (APC). Cohort effect was calculated as the relative rate from the 1984 reference cohort for men and 1987 cohort for women. The period effect in both sexes constrained to be relative to 1390 and to be 0 on average with 0 slope. The best APC model for both sexes was the models with "AC-P" parameter, 7 knots, and natural splines for men and B splines for women. All analyses were performed using the R software with Epi package.
 
Results: The age effect showed that the highest suicide incidence rate was seen in the elderly. Two strong birth cohort effects were observed, one increasing one in the 1980 cohort and one decreasing one in 1991 cohort. The most significant period effect was seen in men in 2011.
 
Conclusion: The effects of 1991 and 1980 birth cohorts could be due to the consequences of imposed war in Iran. The three economic phenomena, oil price change, increased divorce rate, and increased unemployment rate can be effective in the emergence of the period effect in year 2011.