Teacher Stress Inventory: validation of the Greek version and perceived stress levels among 3,447 educators

Background: The Teacher Stress Inventory (TSI) is an instrument for measuring occupational stress in teachers. This study aimed to translate and adapt it for use in Greece, and then assess its reliability and validity. Methods: The Greek versions of the TSI and the 14-item Perceived Stress Scale (PSS-14) were posted on all Greek educators' official sites during May 2012. A nationwide sample of 3,447 teachers of all levels and specialties completed the questionnaires via the Internet. Reliability was determined by the calculation of Cronbach's alpha coefficient. Confirmatory factor analysis was conducted and validity was further examined by investigating the correlation of the TSI with the PSS-14 and their association with demographics and work-related factors. Results: Satisfactory Cronbach's alpha values (above 0.70) were found for all TSI dimensions. Confirmatory factor analysis confirmed the two-factor construct of TSI (root mean square error of approximation, comparative fit index, and goodness-of-fit index values were 0.079, 0.956, and 0.951, respectively), confirming the pre-established theory for the two latent variables, Stress Sources and Stress Manifestations. Significant correlations were found between TSI subscales, PSS-14 sex, age, lack of support, and students' difficulties. Conclusion: The Greek version of the TSI was found to have satisfactory psychometric properties, and its use for assessing stress in Greek teachers is warranted.