Classification of contour deformities after massive weight loss: the applicability of the Pittsburgh Rating Scale in The Netherlands

Abstract

Background: The Pittsburgh Rating Scale is the only validated classification system of skin deformities occurring after massive weight loss. The purpose of this study was to replicate the validation of the Pittsburgh Rating Scale classification and to evaluate its usefulness in the treatment of massive weight-loss patients in The Netherlands.

Methods: Thirteen trained observers applied the Pittsburgh Rating Scale to photographs of 25 patients. These photographs showed the 10 regions of the body for which the Pittsburgh Rating Scale is designed. Six of the observers were medical specialists, three were medical interns in plastic surgery and four observers were specialised nurse practitioners. As a measure of inter-rater agreement we calculated the intraclass correlation with a threshold value of 0.6 for good validity. The observers also answered 11 questions about the scale's usefulness in daily practice.

Results: In two consecutive tests the photographs of 10 regions were scored, which resulted in a total of 20 observations per patient. Sixty percent of the intraclass correlation values were below the threshold of 0.6 for good validity. The mean intraclass correlation value was 0.577.

Conclusions: The Pittsburgh Rating Scale could not be validated as a reliable classification system for skin deformities after massive weight loss. The scale however seems to be a good first step in a challenging task. There was no doubt among the observers that a good classification system would be beneficial for adequate treatment. A modified Pittsburgh Rating Scale should include, besides anatomical parameters, functional disability and hygienic impairment scores and perioperative risk factors.

Keywords: Body-contouring surgery; Classification; Contour deformities; Massive weight loss; Post-bariatric; Rating scale.