RESUMO
AIM: To evaluate validity of the Greek version of a global measure of perceived stress PSS-14 (Perceived Stress Scale - 14 item). MATERIALS AND METHODS: The original PSS-14 (theoretical range 0-56) was translated into Greek and then back-translated. One hundred men and women (39 +/- 10 years old, 40 men) participated in the validation process. Firstly, participants completed the Greek PSS-14 and, then they were interviewed by a psychologist specializing in stress management. Cronbach's alpha (a) evaluated internal consistency of the measurement, whereas Kendall's tau-b and Bland & Altman methods assessed consistency with the clinical evaluation. Exploratory and Confirmatory Factor analyses were conducted to reveal hidden factors within the data and to confirm the two-dimensional character of the scale. RESULTS: Mean (SD) PSS-14 score was 25(7.9). Strong internal consistency (Cronbach's alpha = 0.847) as well as moderate-to-good concordance between clinical assessment and PSS-14 (Kendall's tau-b = 0.43, p < 0.01) were observed. Two factors were extracted. Factor one explained 34.7% of variability and was heavily laden by positive items, and factor two that explained 10.6% of the variability by negative items. Confirmatory factor analysis revealed that the model with 2 factors had chi-square equal to 241.23 (p < 0.001), absolute fix indexes were good (i.e. GFI = 0.733, AGFI = 0.529), and incremental fix indexes were also adequate (i.e. NFI = 0.89 and CFI = 0.92). CONCLUSION: The developed Greek version of PSS-14 seems to be a valid instrument for the assessment of perceived stress in the Greek adult population living in urban areas; a finding that supports its local use in research settings as an evaluation tool measuring perceived stress, mainly as a risk factor but without diagnostic properties.