Journal of Biostatistics and Epidemiology http://jbe.tums.ac.ir/index.php/jbe Tehran University of Medical Sciences en-US Journal of Biostatistics and Epidemiology Multivariate logistic regression analysis using multilevel model http://jbe.tums.ac.ir/index.php/jbe/article/view/204 <p><strong>Background &amp; Aim: </strong>One of the basic assumptions in simple linear regression models is the statistical independence of observations. Sometimes this assumption is not true for study subject and consequently the use of general regression models may not be appropriate. In this case, one of the leading methods is the use of multilevel models. The present study utilizesmultivariate logistic regression model using a multilevel&nbsp; model to exhibit the chance of having elbow, wrist and knee disorders over the past year based on elbow, wrist and disorders during the past week.<br><strong>Methods &amp; Materials:</strong> This study is a cross-sectional study that was carried out from April 2015 to May 2016 in Mobarakeh Steel Company, Isfahan. The study population includes 300 male employees of Mobarakeh Steel Company, with a mean age of 41.40±8.17 years and an average working experience of 16.0±7.66 years. Data were analyzed using SPSS (version 24) and MLwiN software.<br><strong>Results:</strong> Based on this study, results obtained from single variable and multivariable regression were different.<br><strong>Conclusion:</strong> Based on this study, it can be suggested that multivariable regression cause a better and more accurate deduction compared to single variable method.</p> Ahmad Vakili Basir Mohammad Gholami Fesharaki Mohsen Rowzati ##submission.copyrightStatement## 2018-12-05 2018-12-05 4 3 1 5 Alpha-power power distribution http://jbe.tums.ac.ir/index.php/jbe/article/view/182 <p><strong>Background &amp; Aim: </strong>Due to the applicability of the statistical distributions in many areas of sciences, adding parameters to an existing distribution for developing more flexible models have been overlooked in the statistical literatures.<br><strong>Methods &amp; Materials: </strong>A new generalization of power distribution is proposed using alpha power transformation method. The new distribution is more flexible than the power distribution and contains distributions that can be unimodal or right skewed.<br><strong>Results: </strong>We study some statistical properties of the new distribution, including mean residual lifetime, quantiles, mode, moments, moment generating function, order statistics, some entropies and maximum likelihood estimators.<br><strong>Conclusion: </strong>We fit the APP and some competitive models to one real data set and show that the new model has a superior performance among the compared distributions as evidenced by some goodness-of fit statistics</p> Malek Fathizadeh Abbas Mahdavi Leila Jabbari ##submission.copyrightStatement## 2018-12-05 2018-12-05 4 3 11 17 Weighted Negative Binomial-Poisson Lindley with Application to Genetic Data http://jbe.tums.ac.ir/index.php/jbe/article/view/201 <p><strong>Background &amp; Aim:</strong> Mixed Poisson and mixed negative binomial distributions have been considered as alternatives for fitting count data with over-dispersion. This study introduces a new discrete distribution which is a weighted version of Poisson-Lindley distribution.<br><strong>Methods &amp; Materials:</strong> The weighted distribution is obtained using the negative binomial weight function and can be fitted to count data with over-dispersion. The p.m.f., p.g.f. and simulation procedure of the new weighted distribution, namely weighted negative binomial- Poisson-Lindley (WNBPL), are provided. The maximum likelihood method for parameters estimation is also presented.<br><strong>Results:</strong> The WNBPL distribution is fitted to several datasets, related to genetics and compared with the Poison distribution. The goodness of fit test shows that the WNBPL can be a useful tool for modeling genetics datasets. <br><strong>Conclusion:</strong> This paper introduces a new weighted Poisson-Lindley distribution which is obtained using negative binomial weight function and can be used for fitting over-dispersed count data. The p.m.f., p.g.f. and simulation procedure are provided for the new weighted distribution, namely the weighted negative binomial-Poisson Lindley (WNBPL) to better inform parents from possible time of occurrence reflux and treatment strategies.</p> Hossein Zamani Noriszura Ismail Marzieh Shekari ##submission.copyrightStatement## 2018-12-05 2018-12-05 4 3 18 23 A governmental model for special patients http://jbe.tums.ac.ir/index.php/jbe/article/view/197 <p><strong>Background &amp; Aim: </strong>Over the past decades, due to the high acceptance of patients in hospitals, the consequent relapse of the disease, the high cost of treatment and medication, the lack of coordination between the provision of hospital services and the needs of the community, the necessity of paying attention to the status of special patients and conducting a study for designing a suitable model in the country has been increased.<br><strong>Methods &amp; Materials: </strong>This research is descriptive-correlation-exploratory and the data were collected through qualitative and quantitative methods. The research sample involves 392 persons in the quantitative section and 20 in the qualitative section. The research instrument was an open-ended questionnaire and a test; the data were collected using cluster sampling.<br><strong>Results: </strong>A total of 7 factors were identified as the final model of health management services for special patients, including: policymaking and load factor planning (0.72), organizational structure (0.63), government intervention methods in financing (0.81), control mechanism (0.88), government intervention in the affairs of special patients (0.79), pharmaceutical and therapeutic support services and medical aids (0.69), and educational support and prevention services (0.68). Also, the fitting of the designed model is 0.027, indicating appropriate fit for the model. <br><strong>Conclusion: </strong>Providing health services to patients by government has a significant role in the patient health services management, and prevention-based education, identification of primary risk factors, and preventing the epidemics and applying the pattern of health services management to special patients with all dimensions and emphasizing the effective role of government control over the provision of services can lead to presenting executive strategies over time.</p> Esmaeil Hosseini Mahmoud Mahmoudi Majd Abadi Irvan Masoudi Asl Behzad Karami Matin ##submission.copyrightStatement## 2018-12-05 2018-12-05 4 3 24 34 The role of Hospital Performance Assessment on Medical Tourism Development http://jbe.tums.ac.ir/index.php/jbe/article/view/194 <p><strong>Background &amp; Aim</strong>- Medical tourism industry would not be developed without well-known healthcare centers which popular for their therapeutic outcome, efficiency, patient centeredness, responsive to governance and staff orientation. To do so, this study designed and carried out.<br><strong>Materials &amp; Methods-</strong> This was an applied, correlation and cross-sectional study which was done in first quarter of 2018. The population of study consisted of International patient department hospitals staff that were selected randomly (N=263). There were used two kinds of research-made questionnaires for medical tourism development and hospital performance assessment which were included of 14 and 45 questions respectively and validated by experts. The reliabilities determined as 0.85 for medical tourism development and 0.68 for hospital performance assessment by Cronbach’s alpha coefficient .The Pearson correlations counted as 0.85. SPSS version 21 was used for all descriptive and inferential analysis.<br><strong>Results</strong>- It has been shown that there was a significant correlation between all hospital performance assessment dimensions and medical tourism industry (P&lt;0.05). The most correlation related to patient centeredness (r=0.45) and the least went to staff orientation (r=0.30). Total amount of correlation between two variables determined as 0.76.<br><strong>Conclusion</strong>- There was a significant and direct relation between hospital performance assessment dimensions and medical tourism development. So, it is strongly recommended that hospital managers as well as policy makers implement hospital performance strengthening strategies for generating medical tourism attraction.</p> Mona Mohammadnia Kamran Hajinabi Mahmoud Mahmoudi Majd Abadi Ali Komeli ##submission.copyrightStatement## 2018-12-05 2018-12-05 4 3 44 48