Mediating Role of Physical Activity in the Relationship between Personality Traits and Body Mass Index (BMI) among the Participants of the Employees’ Health Cohort Study of Iran (EHC-SIR): A Generalized Structural Equation Modeling - Motevalian, Seyed Abbas; Ahmadi, Seyyed Amir Yasin; Tehrani-Banihashemi, Arash (Iranian Journal of Public Health, 2025)