Showing 3 results for Longitudinal Study
M Gholami Fesharaki , A Kazemnejad, F Zayeri, J Sanati, H Akbari,
Volume 8, Issue 4 (3-2013)
Abstract
Background and Objectives: Since there is inconsistency reports in relationship between shift work (SW) and blood pressure (BP), therefore we aimed to show any association between SW and BP by using of Bayesian Multilevel Modeling, which is a reliable method for this type of analysis.
Methods: The profiles of 4145 workers in Polydactyl Iran Corporation were examined in historical cohort between 1996 until 2008. All relevant analysis was performed by Win Bugs software.
Results: Approximately 98 percent of study population was male. Of total 1886 (45.5%), 307(7.4%), 1952 (47.1%) of participation were day worker, two rotation shift worker and three rotation shift worker respectively. After controlling confounding factors, there was no significant relationship with Systolic BP (P=0.911) and Diastolic BP (P=0.278).
Conclusion: In general, the results of our historical cohort study do not support a relationship between SW and BP. We suggest multi center and prospective cohort studies with controlling more confounding factors in this area.
P Rezanejad Asl , M Hosseini, S Eftekhary, M Mahmoodi , K Nouri,
Volume 10, Issue 3 (12-2014)
Abstract
Background & Objectives : Longitudinal studies are used in many psychiatric researches to evaluate the effectiveness of treatment. The main characteristic of longitudinal studies is repeated measurements of the patients over time. Since observations from the same patient are not independent from each other, especial statistical methods must be used for analyzing the data. Missing data is an indispensable component in longitudinal. In this study, we examined the effect of comprehensive treatment on social-individual performance in patients with the first episode of psychosis.
Methods : The data was from a clinical trial involving patients who were admitted to the clinics of Roozbeh Hospital between 2006_2008. We employed a random effect model for the analysis of longitudinal ordinal responses with non-monotone missingness using the R software version 3.0.2.
Results: The results showed that comprehensive treatment with follow-up at home, age, and family history of the disease had a significant effect on the social-individual performance of the patients. The estimation of the coefficient of age and its standard deviation were 0.05 and 0.03, respectively. The estimation of the coefficient of family history of the disease was -0.82 with a standard deviation of 0.41, and the coefficient of comprehensive treatment with follow-up at home and its standard deviation, were estimated -1.04 and 0.44, respectively.
Conclusion: The model used in this study showed that the comprehensive treatment with follow-up at home was better because individuals under this type of treatment are more likely to have social-individual performance.
F Zayeri, M Amini, H Hasanzadeh,
Volume 13, Issue 4 (3-2018)
Abstract
Background and Objectives: Shift work as a pervasive phenomenon in various industrial sectors is one of the most stressful factors in the workplace. Considering the contradictory reports on the relationship of shift work and hypertension, the main objective of the present study was to investigate the relationship between these two variables among petrochemical industry staff of Mahshahr, Iran.
Methods: In this longitudinal study, 3254 petrochemical staff were investigated during 2008-2011. According to work schedule, shift workers were divided into two groups of shift work and day work (1872 day workers and 1382 shift workers). The aim of this research was to assess the effect of shift work on hypertension by adjusting confounding variables such as gender, age, body mass index, and smoking. The data were analyzed using a random-effects logistic regression model.
Results: Of 3254 (3142 males and 112 females) subjects, 37.85% (860 subject) were hypertensive. The random effects model, with controlling covariates, showed no significant relationship between shift work and hypertension (OR=1.04, 95% CI= (0.98, 1.10). Moreover, the variance of the random effects was significant.
Conclusion: Generally, according to the results of this study, shift work is not a significant risk factor for hypertension.
