Translation of SCAR-Q into Finnish and psychometric validation of the Finnish version.

Background: An effective patient-reported outcome measure for scars is needed to assess scar treatments and thus improve scar management. The recently developed SCAR-Q questionnaire for all scar types, which consists of the Appearance, Symptom, and Psychosocial impact scales, has been developed with patients' input. The aim of this study was to translate the SCAR-Q into Finnish and to assess its psychometric properties in burn patients.

Methods: The translation protocol followed the International Society for Pharmacoeconomics and Outcomes Research guidelines. Participants for the psychometric validation of the Finnish SCAR-Q were adults with deep second or third degree burns treated with skin grafting in the Helsinki Burn Centre between 2006 and 2017. Internal consistency was assessed by using Crohnbach's alpha and reliability by using ICC, SEM, R values, and Mann-Whitney U-test. The internal structure of each SCAR-Q subscale was investigated by using exploratory factor analysis.

Results: 190 burn patients participated in the psychometric validation of the Finnish SCAR-Q. 135 (71.1 %) of the participants were male. Ceiling effect was present in all subscales. Internal consistency was excellent with all subscales, Crohnbach's alpha 0.97, 0.91, and 0.94. Reliability was good in all subscales, ICC 0.84, 0.88, and 0.91. The parallel analysis suggested inclusion of one factor into factor analysis for the Appearance scale and the Psychosocial impact scale, whereas two factors for the Symptom scale.

Conclusion: The Finnish version of the SCAR-Q is equivalent with the original scale, showed excellent internal consistency, factor analysis confirmed it for the Appearance and Psychosocial impact scale, and demonstrated good reliability with all subscales when used in assessing burn scars.