- Record: found
- Abstract: not found
- Article: not found
Validation of a new scale for the assessment of bowel preparation quality
There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
Bowel preparation quality scales are used to document the superiority of one preparation
regime vs. another. The validity and reliability of these scales are not routinely
stated in reports of studies in which the scales are used. A new colonoscopy bowel
preparation scale (the Ottawa bowel preparation scale) was developed and validated
prospectively.
Ninety-seven consecutive patients undergoing elective outpatient colonoscopy were
entered into the study. The quality of the bowel preparation was assessed independently
by two investigators who used the Ottawa scale, and the only other validated scale
(Aronchick scale) that could be identified. The interobserver agreement and reliability
of each scale was assessed by the Pearson correlation coefficient (r), the intraclass
correlation coefficient, and regression analysis.
The Pearson correlation coefficients were, respectively, 0.89 and 0.62 for the Ottawa
and Aronchick scales (p<0.001). The values for the kappa statistic, an intraclass
correlation coefficient measuring agreement over and above chance agreement, were,
respectively, 0.94 and 0.77 (p<0.001). Linear regression analysis, mapping the line
best describing the scatter of scores by raters, for the Ottawa scale revealed a slope
of the line of 0.93 and a y intercept of 0.10. The Aronchick scale revealed a slope
of 0.65 and a y intercept of 0.46. The Ottawa scale thus was closer to an identity
line comparing raters (i.e., closer to a line with slope of 1.00 and y intercept of
0.00). The Ottawa scale demonstrated a right colon kappa (intraclass correlation coefficient)
of 0.92: 95% CI[0.88, 0.95], a mid colon kappa (intraclass correlation coefficient)
of 0.88: 95% CI[0.82, 0.92], and a rectosigmoid kappa (intraclass correlation coefficient)
of 0.89: 95% CI[0.83, 0.92].
The Ottawa scale was validated prospectively and demonstrates high interobserver agreement
and reliability, whether used as a total score or for individual colon segments.