The Italian version of the Sickness Impact Profile-Roland Scale for chronic pain: cross-cultural adaptation, reliability, validity and sensitivity to change

Purpose. As no adapted form of the 23-item Sickness Impact Profile (SIP)-Roland Scale for patients with chronic pain has ever been validated in the Italian population, the aim of this study was to translate, culturally adapt and validate an Italian version. Methods. The development of the Italian version involved translation and back-translation, a final review by an expert committee and the testing of the pre-final version to establish its correspondence with the original. The psychometric testing included testing reliability by internal consistency (Cronbach's α) and test-retest repeatability (intraclass coefficient correlation; ICC), construct validity by comparison with an 11-point pain intensity numerical rating scale (NRS; Pearson's correlation) and the Short Form Health Survey (SF-36; Pearson's correlation) and sensitivity to change by calculating the minimum detectable change (MDC). Results. It took 3 months to obtain a shared version of the scale, which was administered to 243 subjects and proved to be satisfactorily acceptable. It had a high degree of internal consistency (α=0.860) and test-retest reliability (ICC=0.972). Construct validity testing revealed a moderate correlation with the NRS (r=0.418), close correlations with the SF-36 physical subscales and moderate-poor correlations with the mental and social subscales; the MDC was 2.33. Conclusions. The SIP-Roland scale was successfully translated into Italian, showing satisfactory psychometric properties. The measure can be recommended for use in research and clinical practice to improve the assessment of physical dysfunction in subjects with chronic pain.