The self-administered Cochin 17-item Scleroderma Functional scale (CSF-17) provides reliable patient-reported outcome assessment of mobility and general tasks in patients with systemic sclerosis, study data in the British Journal of Dermatology suggest.
Patients with systemic sclerosis who were enrolled in the Scleroderma Patient-centered Intervention Network Cohort (n=184) were emailed a provisional 65-item International Classification of Functioning, Disability and Health (ICF)-based questionnaire that was developed on the basis of interviews of patients with the disease.
In addition to the 65-item questionnaire, participants also completed other patient-reported outcome measures, including 5 activity limitation scales, a health-related quality-of-life (HRQoL) scale, and 3 impairment scales. Respondents were followed up at the internal medicine department of Cochin hospital for survey question reduction and assessment of psychometric properties. Patients’ input was used to reduce the number of items on the 65-item ICF-based questionnaire in an effort to make the survey more time efficient and less burdensome. Items with a response rate <90% were removed. Test-retest reliability and agreement assessments were conducted in an independent sample of 75 French patients with systemic sclerosis.
More than half (61.4%) of the participants completed the provisional questionnaire. After the item reduction process, a total of 17 items remained in the ICF-based questionnaire, which was termed the CSF-17. The 2 dimensions extracted from the principal component analysis included 10 items related to mobility (section A) and 7 items related to cognitive functions and complex tasks (section B). In regard to test-retest reliability, the intraclass correlation coefficients were 0.92 (95% CI, 0.83-0.96) for the CSF-17 total score, 0.90 (95% CI, 0.79-0.95) for section A, and 0.94 (95% CI, 0.85-0.97) for section B.
The recruitment of only French patients as well as the small sample size were noted as study limitations.
The researchers note that the questionnaire’s “content validity and psychometrics properties are very good,” and they are currently planning to use the international Scleroderma Patient-centered Intervention Network Cohort for additional external validation of the assessment tool.
Daste C, Abdoul H, Foissac F, et al. Development of a new patient-reported outcome measure to assess activities and participation in people with systemic sclerosis: The Cochin 17-item Scleroderma Functional Scale [published online February 4, 2020]. Br J Dermatol. doi: 10.1111/bjd.18922