Intra and inter-observer agreement on polyp detection in colon capsule endoscopy evaluations

Background: Colon capsule endoscopy is a promising technique for evaluation of the colon, but its reproducibility is still unknown. 

Objective: This study assesses intra and inter-observer agreement in evaluations of colon capsule endoscopy videos. 

Methods: Forty-two complete colon capsule endoscopy investigations were analysed by three experts and two beginners. Intra-observer agreement was assessed in paired readings of two experts and two beginners. Agreement was determined by the intraclass correlation coefficient: poor (<0.5), moderate (0.5–0.75), good (0.75–0.9) and excellent (>0.9). 

Results: Agreement on ‘indication for a following colonoscopy’ based on the number and size of detected polyps and bowel cleansing quality was poor among all observers. Agreement among experts on the detection of large polyps and number of polyps was moderate, but agreement on bowel cleansing quality was poor. Beginners were in moderate agreement with the experts on polyp detection. Intra-observer agreement in experts was moderate to excellent for the detection of large polyps (≥10 mm), excellent for the number of polyps, and poor to moderate for bowel cleansing quality. Intra-observer agreement in beginners was poor to moderate for all variables. 

Conclusions: This study shows a poor agreement on ‘indication for a following colonoscopy’, but a high intra and inter-observer agreement for polyp detection among experts, as well as a moderate agreement between beginners and experts.