Journal of School of Public Health and

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Background and Aim: Children are one of the most vulnerable groups in the population. Child abuse is a complex phenomenon with multiple causes. The purpose of this study was to do a confirmatory factor analysis of child abuse potential inventory among Ahvazi children in Ahvaz, Iran.

Materials and Methods: This was a descriptive-analytical study, including all Ahvazi primary school pupils aged 8-13 years in the academic year 2015-2016.

The sample size for confirmatory factor analysis was determined based on the number of questions per parameter.The variance was extracted on the basis of mean scores and

composite reliability for structural equation modeling was determined based on the first-order and second-order confirmatory factor analysisusing the LISREL software.

Results: Confirmatory factor analysis revealed a short form of the child abuse's original 3-actor structure, including the psychological, physical and neglect scales. The outcomes indicated that the firstorder model was a better fit for the data than the second.

Conclusion: It can be concluded that the Ahvazi version of the child abuse potential inventory questionnaire is acceptable from a psychometric point of view. We think it is essential to take into consideration the diversity of perspectives between parents and children in future research in this area.

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Background and Aims: Generalized Structural Equation Modeling (GSEM) is a family of statistical techniques utilized in the analysis of multivariate, categorical and ordinal data in order to measure latent variables and their connection with each other. The aim of this study is to consider the structure of data, and introducing GSEM to medical science researchers and presenting a practical example of in medical science researches.

Materials and Methods: An introduction to Structural Equation Modeling (SEM), along with its advantages and disadvantages was presented, and also GSEM and its all kind of forms was specified. An example to study hypertension risk factors in patients suffering from diabetes was carried out, which was a demonstration of using GSEM method for binary response variables. The data includes a random sample of 2716 people from Golestan province cohort studies.

Results: Age, body mass index, abdominal obesity, residence place, socioeconomic status, salt intake had direct effect on hypertension. Race, education, vitamin D and physical activity had direct and reverse effect on hypertension (p.value<0.05).

Discussion: Unlike SEM, the limitative hypothesis that our data should have a normal distribution do not needed in this model, also GSEM is powerful tool in the analysis of categorized data. Nevertheless this method cannot perform goodness of fit test, and adjustment and modification method of the model directly, and that they are some limitation in using this method.

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Background and Aim: Good governance results in better health outcomes for the society thorugh improving health system performance. The governance of Iran health stsyem faces some challenges. Hence, this study aimed to propose and verify a model for strengthening Iranian health system governance.
Materials and Methods: This descriptive study was conducted in 2016 using the Delphi method. A health governance model with six dimentions including sturucture, communication, regulation, policy making and planning, stewardship and evaluation and accreditation has been proposed. Then, the proposed model verified using 25 Iranian healthcare experts’ opinions in two rounds.
Results: Developing an integrated health system model comprising health system enablers and results, downsizing and reducing the number of directorates in ministry of health,determining basic principles for regulation, enhancing communication with other external organizations affecting people health, using more evidence in policy making and planning, developing a strategic plan and national health policy, enhancing leadership, management and stewardship; and developing comprehensive systemic standards for evaluation and accreditation of healthcare organizations are recommended to enhance the effectiveness and efficiency of Iran health system governance.
Conclusion: Iran health system governance faces numerous challenges. Using successful countries’ experience and internal health care experts’ opinions help to reduce the current challenges and achieve health system goals.
 

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Background and Aim: High concentrations of particulate matter-25 (PM_2.5) have been the cause of the unhealthiest days in Tehran, Iran in recent years. This study was conducted with the aim of the spatio-temporal analysis of traffic volume and its relationship with PM_2.5 pollutant concentrations in Tehran metropolis, Tehran during 2015-2018, using the Geographic Information System (GIS).
Materials and Methods: In this study in different regions of Tehran, the Inverse Distance Weighting (IDW) model was used for prediction and zoning of the PM_2.5 concentrations and traffic volume during the period 2015-2018. In addition, the association between the PM_2.5 concentrations and traffic volume was determined based on the Geographically Weighted Regression (GWR) model.
Results: The findings showed that the southern and southwestern regions of Tehran had the highest PM_2.5 pollutant concentration (annual average more than 40 μg/m³), while the eastern and northern regions had the highest traffic volume. In addition, based on the GWR model, the eastern regions were found to have the highest local R² values (between 0.36 and 0.70).
Conclusion: In most regions of Tehran, no strong association can be found between high concentrations of PM_2.5 and traffic volume. However, based on the findings of this study we cannot reject the relationship between traffic volume and PM_2.5 pollutant but postulate other sources to be the main reason for the high concentrations of PM_2.5. Thus, in the first step, these sources should be identified, followed by adopting strategies for traffic volume control and reduction aiming at having a cleaner air in Tehran.