BACKGROUND: Clinical scales are useful to assess skin laxity in different areas of the body. OBJECTIVE: To elaborate and validate a photonumeric scale to assess buttocks skin laxity. MATERIALS AND METHODS: The Buttocks' Skin Laxity Severity Scale (SLSS) was developed based on a sample of 120 patients. The SLSS validity and reliability were assessed in 2 validation cycles, performed by 8 dermatologists assessing 50 clinical cases. Both criteria and construct validity were tested. RESULTS: The Buttocks' SLSS is composed by 5 clinical aspects of skin laxity graded from absent (0) to severe (3): buttocks ptosis, skin scalloped appearance, infragluteal fold, localized fat on the lower third of the buttocks, and linear depressed lesions. Final skin laxity classification results from the sum of each item grade multiplied by its weight and varies from 0 to 24. Overall, Kendall, weighted kappa, and intraclass correlation coefficients indicated very good reliability and consistent interrater and intrarater agreement (p < .001). Cronbach alpha of 0.82 indicates high scale reliability. The scale validity was confirmed by criteria validity tests (rs: 0.72, p < .05). CONCLUSION: Buttocks' SLSS is a reliable and valid scale to identify skin laxity severity and its different features, and it is an accurate tool for clinical research.
BACKGROUND: Clinical scales are useful to assess skin laxity in different areas of the body. OBJECTIVE: To elaborate and validate a photonumeric scale to assess buttocks skin laxity. MATERIALS AND METHODS: The Buttocks' Skin Laxity Severity Scale (SLSS) was developed based on a sample of 120 patients. The SLSS validity and reliability were assessed in 2 validation cycles, performed by 8 dermatologists assessing 50 clinical cases. Both criteria and construct validity were tested. RESULTS: The Buttocks' SLSS is composed by 5 clinical aspects of skin laxity graded from absent (0) to severe (3): buttocks ptosis, skin scalloped appearance, infragluteal fold, localized fat on the lower third of the buttocks, and linear depressed lesions. Final skin laxity classification results from the sum of each item grade multiplied by its weight and varies from 0 to 24. Overall, Kendall, weighted kappa, and intraclass correlation coefficients indicated very good reliability and consistent interrater and intrarater agreement (p < .001). Cronbach alpha of 0.82 indicates high scale reliability. The scale validity was confirmed by criteria validity tests (rs: 0.72, p < .05). CONCLUSION: Buttocks' SLSS is a reliable and valid scale to identify skin laxity severity and its different features, and it is an accurate tool for clinical research.