The aim was to translate, revise, and standardize the Perceived Stress Questionnaire (PSQ) by Levenstein et al. (1993) in German. The instrument assesses subjectively experienced stress independent of a specific and objective occasion.
Exploratory factor analyses and a revision of the scale content were carried out on a sample of 650 subjects (Psychosomatic Medicine patients, women after delivery, women after miscarriage, and students). Confirmatory analyses and examination of structural stability across subgroups were carried out on a second sample of 1,808 subjects (psychosomatic, tinnitus, inflammatory bowel disease patients, pregnant women, healthy adults) using linear structural equation modeling and multisample analyses. External validation included immunological measures in women who had suffered a miscarriage.
Four factors (worries, tension, joy, demands) emerged, with 5 items each, as compared with the 30 items of the original PSQ. The factor structure was confirmed on the second sample. Multisample analyses yielded a fair structural stability across groups. Reliability values were satisfactory. Findings suggest that three scales represent internal stress reactions, whereas the scale “demands” relates to perceived external stressors. Significant and meaningful differences between groups indicate differential validity. A higher degree of certain immunological imbalances after miscarriage (presumably linked to pregnancy loss) was found in those women who had a higher stress score. Sensitivity to change was demonstrated in two different treatment samples.
We propose the revised PSQ as a valid and economic tool for stress research. The overall score permits comparison with results from earlier studies using the original instrument.
PSQ = Perceived Stress Questionnaire; ICD = International Classification of Diseases; QoL = quality of life; IBD = inflammatory bowel disease; SEM = structural equation modeling; MSA = multisample analysis; TLI = Tucker-Lewis index; CFI = comparative fit index.
From the Department of Psychosomatic Medicine, Charité-University Hospital Berlin, Berlin, Germany.
Received for publication December 1, 2003; revision received August 19, 2004.
Address correspondence and reprint requests to Dr. Herbert Fliege, Department of Psychosomatic Medicine, Charité - University Hospital Berlin, Luisenstrasse 13 a, D-10117 Berlin, Germany. E-mail: email@example.com
Financial aid was granted by the Humboldt-University Medical Faculty Research Fund (UFF-N°. 99–648/99–652). The ethics committee approved of the study design (N° 209/98/107/99).