INTER-OBSERVER AGREEMENT IN BROTZ CLEANING SCALES FOR CAPSULE ENDOSCOPY

Aims:

The diagnostic yield of capsule endoscopy (CE) depends on the adequate visualization of the mucosa. As with colonoscopy, cleaning scales should be described in the report in order to better interpret results. In 2008, Brotz et al proposed and validated 3 different cleansing scales. The aim of this study was to evaluate the inter-observer variability of this cleaning scales.

Methods:

A hundred CE videos (Mirocam) were reviewed by 2 authors at a fixed frame rate of 100 frames per second in quadruple view (Miroview Client). The CE were evaluated according to the Brotz scales:

1. Overall adequacy assessment (adequate/inadequate)

2. Qualitative scale (excellent, good, fair, poor) and

3. Quantitative scale (0 – 10 score, graded from 0 – 2 visualization of the mucosa, fluids, bubbles, bile and luminosity).

The kappa coefficient was used to calculate the inter-observer agreement in overall adequacy assessment and the intra-class correlation coefficient was used to evaluate the concordance of the qualitative and quantitative scales.

Results:

In overall adequacy assessment, the quality of intestinal small bowel preparation was classified as adequate by observer 1 in 67% and by observer 2 in 73%, with an inter-observer kappa index of 0.76 (p > 0.001) suggesting strong agreement.

In the qualitative scale, most of the intestinal small bowel preparations were considered reasonable (40% observer 1 vs. 36% observer 2), with an intra-class coefficient of 0.89 (p < 0.001).

In the quantitative scale, the mean score of the two observers was 6.5 and 6.7, resulting in an intra-class agreement of 0.78 (p < 0.001).

Conclusions:

The optimization of the quality of the intestinal small bowel preparation and the diagnostic yield of the CE requires, first, a well-validated cleaning scale. Brotz's rating scales have strong inter-observer agreement. The qualitative scale is easier to apply and has better inter-observer agreement.