Purpose: This study tested the scale properties and validity of the ten-item body image scale (BIS) in patients undergoing surgery for colorectal cancer (CRC).
Methods: Patients completed the BIS and a validated measure of health-related quality of life (European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30) after open or laparoscopic resection. A sample of the patients had also previously completed questionnaires before and after surgery. Multi-trait scaling and factor analysis were used to examine the questionnaire scaling, and tests of reliability, clinical and construct validity were performed.
Results: Eighty-two patients (48 male, 59 open, 23 laparoscopic) participated. Scaling analyses suggested a nine-item scale and one single item. This revised scale structure demonstrated good test-retest reliability (r = 0.94) and no overlap with the key domains of the EORTC QLQ-C30 (r < 0.40). Patients with a stoma reported significantly poorer BIS scores than those undergoing simple resection (p = 0.005).
Conclusions: This study provides psychometric and clinical evidence for a revised scale structure for the BIS in CRC, and the questionnaire is suitable to assess body image in CRC clinical trials.