Comparison of the Boston Bowel Preparation Scale with an Auditable Application of the US Multi-Society Task Force Guidelines.

For all scales, intra-rater kappas were superior to inter-rater values, the latter reflecting at best moderate agreement. This modest performance may reflect the dichotomized interpretation of the scales (adequate versus inadequate), differing from previous publications assessing scores as continuous variables. Further studies are required to optimally interpret bowel preparation scales with regard to interval to next colonoscopy.