SESQ, a patient-reported outcome instrument addressing excess skin; report on the updated version and the validation process.

Excess skin after weight loss is perceived as a major problem for the majority of the bariatric patients, between 68 and 90% desire additional reconstructive surgery. However, only about 20% of the patients actually have the possibility to undergo these procedures. Reliable and valid patient-reported outcome instruments, PROM, are required in order to consider the patients' perspective of excess skin when discussing reconstructive surgery. The aim of this study was to present the updated version of Sahlgrenska Excess Skin Questionnaire, SESQ and to report on the validation process. The material for the process to evaluate internal consistency and known group validity was based on four different studies conducted at the Department of Plastic Surgery at Sahlgrenska University Hospital, Sweden. Internal consistency was high in all four groups examined; the normal population, the obese patients, the post-bariatric patients and the post-abdominoplasty patients. Values for Cronbach's alpha were >0.86 in all groups, and the highest value was seen in the obese patients (0.92). Furthermore, regarding known group validity, there were strong significant differences between the answers from the normal population in comparison with most of the other studies. In conclusion, patients thought that the questions in SESQ were easy to understand, that they covered all appropriate aspects of excess skin and the patients did not think that SESQ overlooked any questions or aspects concerning excess skin. SESQ is a valid questionnaire addressing excess skin in post-bariatric patients. The updated version of the SESQ is both accurate and user-friendly.