Tehran University of Medical Sciences Iranian Journal of Psychiatry 1735-4587 9 1 2014 03 15 1 7 Ali Reza Soltanian Department of Biostatistics & Epidemiology, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran Mohammad Amiri Section of Healthy heart, the Persian Gulf Health Research Center, Bushehr University of Medical Sciences, Bushehr, Islamic Republic of Iran Soudabeh Namazi Department of Psychologic, Bushehr University of Medical Sciences, Bushehr, Iran Hossein Qaedi Department of Management and Health Care, School of Public Health, Bushehr University of Medical Sciences, Bushehr, Islamic Republic of Iran Gholam Reza Kohan Department of Health, Bushehr University of Medical Sciences, Bushehr, Iran 2015 10 14 This 7-year observational study examines the hours of TV-watching, phone conversation with friends, using the internet, and physical activity as predictors of mental health among adolescents in south of Iran.At the baseline (in 2005), the participants were 2584 high school students in the 9th to 11th grade. At the baseline, 30% of the available participants (n = 775) were selected in the follow-up (2012) using convenience sampling method. This study used the path analysis to examine the predictors of mental health and to obtain direct, indirect and total effects of the independent variables.At the baseline (2005), female gender, internet use, maternal education, physical activity and father's education were associated with mental health (p<0.05). Baseline mental health, internet use and physical activity predicted mental health of the participants in the follow up (p<0.05).The findings of the study revealed that better mental health in later life is associated with better mental health at baseline, male gender, higher physical activity and phone communication with friends, and less use of the internet and TV. https://ijps.tums.ac.ir/index.php/ijps/article/view/140 https://ijps.tums.ac.ir/index.php/ijps/article/download/140/136