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Background & objectives: One of the factors affecting the performance of video display terminal users is their mental work load. Since low sleep quality causes fault and decreased accuracy in work, this study aimed to evaluate the relationship between mental work load and sleep quality in video display terminals users.
Methods: This descriptive cross-sectional study was performed on 191 video display terminal users. National Aeronautics and Space Administration Task Load Index questionnaire (NASA TLX) which is a six-dimensional tool and measures mental, physical, temporal, performance, Frustration and Effort demands, was used in the study. For evaluation of sleep quality, Pittsburgh Sleep Quality questionnaire was used. Data were analyzed by descriptive statistics, independent T-test, one way ANOVA, Pearson correlation coefficient and regression analysis in SPSS version 20 software.
Results: Mean score of sleep quality and mean of overall mental work load were 6.29±2.67 and 66.61±17.69, respectively. Pearson correlation coefficient showed no significant relationship between mental work load and sleep quality (p=0.34, r=-0.06). Independent       T-test showed that there was a significant difference in sleep quality between males and females (p=0.001). 39.2% of participants demonstrated good sleep quality, 4/52% relatively low quality and 4/8% low sleep quality. NASA-TLX showed that the lowest and highest scores of six scales were related to physical demand (16.27±22.43) and mental demand (78.57±21.31), respectively.
Conclusion: In this study, there was no significant relationship between mental work load and sleep quality. Since mental work load was high in video display terminal users, use of effective programs to reduce the mental work load seems to be essential for these users.

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Background & objectives: The quality of sleep and life are variables that have a very important role in organizing the social, physical and psychological aspects of human. This study aimed to compare the quality of life and sleep of active and passive soldiers.
Methods: Among 400 soldiers of shahid Abbas Doran Air Force base in Shiraz, 200 soldiers were selected by available sampling method and participated in this descriptive study. They were divided into two groups of active and inactive based on the amount of their physical activity per week and completed the Pittsburgh sleep quality and quality of life (SF-36) questionnaires. For data analysis, Mann-Whitney test was used in SPSS-16 software.
Results: The results showed that there was no difference between passive and active soldiers in the scale of the delay in falling asleep (p=0.41) and use of sleep medications (p=0.13), While there was a significant difference in overall score and other sleep quality variables (p<0.05). It was also found that there were significant differences in the quality of life variables between active and inactive soldiers (p<0.05).
Conclusion: Since active soldiers have better sleep quality and quality of life than passive soldiers, it can be concluded that the physical activity and exercise can have a positive impact on the quality of sleep and life of soldiers.

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Background & objectives: The aging population of the world is increasing. One of the problems that occur along with age is sleep disorder, leading to a gradual decrease in the quality of life in the elderly. The aim of this study was to evaluate the quality of sleep and related factors in the elderly patients hospitalized in Imam Khomeini Hospital of Khalkhal in 2016.
Methods: The present study was a descriptive-analytic study, performed on 409 elderly patients admitted to Imam Khomeini Hospital in Khalkhal city in 2016. Data collection tool was a Pittsburgh Sleep Quality Questionnaire. Data were analyzed using SPSS software.
Results: The findings of this study showed that the mean and standard deviation of total sleep quality score of participants in the study was 8.61±3.31. The average sleep quality score in women was higher than men and men had better sleep quality, however, no significant differences was observed between two genders. The relationship between demographic variables and sleep quality in the elderly showed no significant relationship between age and number of children with sleep quality. There were significant relationships between other variables such as marital status, occupation type, income level and hospitalization unit with sleep quality (p<0.05).
Conclusion: The results of this study indicated that the sleep quality of elderly patients in studied hospital was low and directly related to some of the underlying variables. So, it is necessary to take measures in hospitals to reduce sleep disorders.

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Background & objectives: Coronavirus disease (Covid-19) can have several psychological effects. This research aimed to investigate mental health status and its relationship with the sleep quality of healthcare workers during the covid-19 pandemic in southern Iran. 
Methods: This‌ descriptive-analytical cross-sectional study was conducted in 2021 on 496 personnel of Hazrat Ali Asghar (AS) Hospital, the center of COVID-19 in Fars province. The participants were selected using the census method. The online General Health Questionnaire (GHQ) and Pittsburgh Sleep Quality Index (PSQI) were provided for participants. Data were analyzed using t-test, ANOVA, and Pearson correlation coefficient in SPSS23 at a significance level of 0.05. 
Results: The mean mental health and sleep quality scores were 48.73±17.14 (of 84) and 8.43±6.21 (of 21), respectively. It indicates a high probability of developing mental health disorders and poor sleep quality among participants. We saw a positive and significant correlation between mental health and sleep quality (p= 0.01, r= 0.33). The level of mental health disorders was significantly higher in single participants (p= 0.02) and participants with bachelor's degrees (p= 0.04). Also, the sleep quality of males (p= 0.03) and single employees (p= 0.04) was significantly lower than the others.
Conclusion: The participants had high mental health disorders, and their sleep quality seems unfavorable. Supportive interventions, counseling, and psychological services are recommended to reduce mental health disorders and improve sleep quality.
 

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Background & objectives: Sleep is essential for physical and mental restoration, crucial for enhancing athletic performance. Vitamin D plays both direct and indirect roles in sleep regulation, with deficiencies linked to sleep disorders. This study aimed to explore the sleep quality (SQ) of young soccer players and its relationship with their vitamin D status.
Methods: This descriptive-analytical study included 75 young male soccer players, aged 18-22 years, with over three years of sports experience, selected through simple random sampling. The Pittsburgh Sleep Quality Index (PSQI) was used to assess SQ, with scores of 5 or above indicating poor SQ. Levels of 25-hydroxyvitamin D (25(OH)D) were measured using ELISA. Spearman's correlation coefficient was employed to evaluate the relationship between 25(OH)D levels and SQ (p≤0.05).
Results: The study revealed that 22.67% of participants had vitamin D deficiency, and 40% had insufficient vitamin D levels. Additionally, 69.33% of participants exhibited poor SQ. A significant positive correlation was found between 25(OH)D levels and SQ among players with deficient and insufficient vitamin D levels (p<0.05).
Conclusion: Vitamin D deficiency and poor SQ are prevalent among young soccer players, and inadequate vitamin D levels may be associated with poor SQ, especially in winter. It is recommended that athletes maintain adequate vitamin D levels to enhance sports performance.