Reliability and Validity of Persian Version of Perceived Stress Scale (PSS-10) in Adults with Asthma

Background: Asthma is a major public health problem in the world, and recent findings suggest that stress inluences asthma and asthma morbidity. The 10-item Perceived Stress Scale (PSS-10) is one of the most frequently used instruments to measure psychological stress. This study was conducted to evaluate the psychometric properties of the Persian versions of the PSS-10 in adults with asthma. Methods: In this descriptive cross-sectional study as a methodological research, 106 asthmatic patients referring to several clinics in Sanandaj (western Iran) were selected through convenience sampling. The PSS-10 and the 21-item Depression anxiety and stress scale (DASS-21) were administrated to all patients. Cronbach s alpha was used to evaluate reliability of PSS-10, and confirmatory factor analysis (CFA) and convergent validity were used to evaluate its validity. Results: The results of confirmatory factor analysis indicated that a two-factor structure of PSS-10 provided a good fit to data. The Cron- bach s alpha coefficients for negative factor, positive factor and total score (PSS-10) were 0.86, 0.83, and 0.90, respectively. The PSS-10 was positively correlated with the DASS-21 and its subscales, indicating an acceptable convergent validity. Female asthmatic patients scored higher on PSS-10 in comparison with male asthmatic patients. Conclusion: The Persian version of PSS-10 is a valid and reliable instrument to measure perceived stress in adults with asthma.