Abstract
Background: Development of tools for measuring stress has been considered by mental health researchers for many years. The purpose of this study was to develop and validate a "Stressful Events Inventory"(SEI) using exploratory and confirmatory factor analyses. Methods: Using a representative sample (n=6000) from all people who reside in Tehran, the validity of the inventory was confirmed by exploratory and confirmatory factor analyses, and its reliability was also confirmed by Cronbach's alpha. Results: Eleven major sets of stressful events were identified as follow: political problems (α=0.731), neighborhood's problems (α=0.739), livelihood problems (α=0.609), fear of the future (α=0.663), educational events (α=0.635), educational changes (α=0.704), individual changes (α=0.463), occupational difficulties (α=0.64), housing problems (α=0.69), problems related to occupational relations (α=0.46), and family problems (α=0.69). The value of correlation between the factors was equal to 0.82 and the value of variance determined by these factors was 0.49 (r^2=0.49). In the confirmatory factor analysis, these factors also had an appropriate fitness (RMSEA=0.02). Conclusion: The developed instrument has suitable psychometric properties, which make it appropriate for future research on psychosocial stress.