Development of the Italian version of the Pain Catastrophising Scale (PCS-I): cross-cultural adaptation, factor analysis, reliability, validity and sensitivity to change.

Purpose The aim of this study was to create an Italian version of the Pain Catastrophising Scale (PCS-I) and evaluate its psychometric properties in a sample with chronic low back pain. Methods The PCS was culturally adapted in accordance with international standards. The psychometric testing included factor analysis, reliability by internal consistency (Cronbach’s alpha) and test–retest repeatability (intraclass coefficient correlations), and concurrent validity by comparing the PCS-I with a numerical rating scale (NRS), the Tampa Scale of Kinesiophobia (TSK), the Roland Morris Disability Questionnaire (RMDQ), the Hospital Anxiety and Depression Scale (HADS) and the Positive Affect and Negative Affect Scale (PANAS) (Pearson’s correlation). Results It took 4 months to develop an agreed version of the PCS-I, which was satisfactorily administered to 180 subjects with chronic low back pain. Factor analysis revealed a three-factor 13-item solution (68% of explained variance). The questionnaire was internally consistent with one exception (a = 0.92 as a whole; 0.89 for Helplessness, 0.87 for Rumination and 0.56 for Magnification subscales) and showed a high degree of test–retest reliability (ICC = 0.842). Concurrent validity showed moderate correlations with the NRS (r = 0.44), TSK (r = 0.59), RMDQ (r = 0.45), HADS (Anxiety: r = 0.57; Depression r = 0.46) and PANAS (Negative Affect r = 0.54). The minimum detectable change was 10.45. The subscales were also psychometrically analysed. Conclusion The successfully translated Italian version of the PCS has good psychometri