Minimal important difference in weight loss following bariatric surgery: Enhancing BODY‐Q interpretability

Abstract

SummaryBODY‐Q is a patient‐reported outcome measure for comprehensive assessment of outcomes specific to patients undergoing bariatric surgery. The clinical utility of BODY‐Q is hampered by the lack of guidance on score interpretation. This study aimed to determine minimal important difference (MID) for assessment of BODY‐Q. Prospective BODY‐Q data from Denmark and the Netherlands pre‐ and post‐bariatric surgery were collected. Two distribution‐based methods were used to estimate MID by 0.2 standard deviations of baseline scores and the mean standardized response change of scores from baseline to 3‐years postoperatively. In total, 5476 assessments from 2253 participants were included of which 1628 (72.3%) underwent Roux‐en‐Y gastric bypass, 586 (26.0%) sleeve gastrectomy, 33 (1.5%) gastric banding, and 6 (0.03%) other surgeries. The mean age was 45.1 ± 10.9 with a mean BMI of 46.6 ± 9.6. Baseline MID ranged from 1 to 4 in health‐related quality of life (HRQL) and from 2 to 8 in appearance scales. The mean change of scores ranged from 4 to 5 in HRQL and from 4 to 7 in the appearance scales. The estimated MID for the change in BODY‐Q HRQL and appearance scales ranged from 3 to 8 and is recommended for use to interpret BODY‐Q scores and assess treatment effects in bariatric surgery.