Comprehensive validation of the Boston Bowel Preparation Scale

Background: The Boston Bowel Preparation Scale (BBPS) is a novel bowel cleanliness rating scale that has undergone partial validation previously.

Objective: To fully validate the BBPS and assess the ease of its dissemination.

Design: Observational study.

Setting: Various endoscopy units worldwide.

Subjects: Endoscopists.

Methods: Video recordings of colonoscopies with varying degrees of cleanliness were viewed twice by gastroenterologists at 1 medical center. For each video, participants assigned segment and total BBPS scores. Endoscopists worldwide were also surveyed about their experience with the BBPS after viewing an instructional video.

Main outcome measurements: Intraclass correlation coefficients and weighted κ values assessed inter- and intrarater reliability, respectively. The BBPS was used among 983 patients undergoing screening colonoscopy.

Results: The BBPS demonstrated near-perfect interrater reliability (intraclass correlation coefficient = 0.91) and substantial intrarater reliability (weighted κ = 0.78; 95% CI, 0.73-0.84). Among 983 colonoscopies, right and left colon segment scores of 2 or 3 had a multivariate odds ratio of 1.60 (95% CI, 1.01-2.55) and 2.58 (95% CI, 1.34-4.98), respectively, for polyp detection compared with segment scores of 0 or 1. Endoscopists from a variety of settings worldwide found the BBPS easy to implement and applicable to their patient population.

Limitations: Single-center reliability testing.

Conclusions: The BBPS is a valid and reliable instrument for assessing bowel cleanliness during colonoscopy. Segment scores may represent a standardized way to determine bowel preparation adequacy. The BBPS can be easily disseminated through the use of a brief instructional video.