Translation, Cross-Cultural Adaptation, and Reliability of the EULAR Systemic Sclerosis Impact of Disease (ScleroID) questionnaire in a Danish population

Abstract
Objectives
This study aims to translate and cross-culturally adapt the European Alliance of Associations for Rheumatology (EULAR) Systemic Sclerosis Impact of Disease (ScleroID) questionnaire to Danish; and to assess its reliability in patients with systemic sclerosis (SSc).

Method
The translation and cross-cultural adaptation of the ScleroID questionnaire were conducted according to COnsensus-based Standard for the selection of health Measurement INstruments (COSMIN) guidelines. The test–retest reliability was assessed in 50 Danish patients with SSc.

Results
All steps for the translation process were followed and approved by the developers of ScleroID. The translation process resulted in changes to the wording of ‘aspects’ to ‘symptoms’, ‘phenomenon’ to ‘syndrome’, and ‘social life’ to ‘social relations and leisure activities’ to create a more meaningful translation in a Danish context. For the Danish version of the ScleroID, the intraclass correlation coefficient (ICC) was 0.90 [95% confidence interval (CI) 0.83; 0.94]. The ICC for each of the 10 individual health domains in ScleroID ranged from 0.52 (95% CI 0.29; 0.70) (digital ulcers) to 0.87 (0.78; 0.92) (lower gastrointestinal symptoms and fatigue).

Conclusion
The overall ICC for the Danish version of the ScleroID was excellent, which indicates that it can be implemented as a reliable patient-reported outcome measure in patients with SSc in Denmark.