International validation of a PEACE scale assessing cleanliness during esophagogastroduodenoscopy to improve the quality of inspection during endoscopy

Aims Upper gastrointestinal (UGI) endoscopy quality depends on the capability to detect mucosal pathologies. Proper visibility is necessary to identify lesions and subtle mucosal abnormalities. The PEACE scale (Polprep: Effective Assessment of Cleanliness in Esophagogastroduodenoscopy) was recently created to assess UGI cleanliness. Cleanliness assessed using the PEACE scoring system was directly related to detection of clinically significant pathologies ¹. The aim of this study was to validate the concordance of the PEACE scoring system globally.

Methods A group of 16 international experts participated in the study. Prior to the video assessment, the experts underwent training on the PEACE scale scores using 21 photographs and 8 videos. In a single round between April and June 2023, the experts assessed 39 videos of three segments (esophagus, stomach, duodenum). The cleanliness of the mucosa on each video was rated using the PEACE scale – from 0 to 3 (0=completely obscured, 1=poor visibility, 2=good visibility, 3=excellent visibility). To evaluate agreement of all scores (0 – 3) intraclass correlation coefficient (ICC 2.1) was used. The agreement on adequate (scores 2 and 3) and inadequate (scores 0 and 1) cleanliness was assessed with Conger's kappa value. ICC values 0.5 – 0.75 were considered as moderate, 0.75 – 0.9 as good, and>0.9 as excellent. Kappa values 0.33 – 0.5 were considered as fair, 0.5 – 0.67 as moderate, 0.67 – 0.9 as substantial, and over 0.9 as almost perfect.

Results The overall agreement on PEACE scores was good (0.82 95% CI 0.75 – 0.89). The agreement was good in esophagus (0.84; 95% CI 0.71 – 0.95), and stomach (0.81; 95% CI 0.69 – 0.91) and moderate in duodenum (0.69; 95% CI 0.51 – 0.87). The concordance between Eastern and Western experts was comparable (0.86; 95% CI 0.79 – 0.92 and 0.80; 95% CI 0.72 – 0.88 respectively) being good in both cases. The overall agreement in identification of inadequate cleanliness (scores 0 and 1) was substantial (0.75; 95% CI 0.65 – 0.85). It was substantial in stomach and esophagus (stomach 0.77; 95% CI 0.62 – 0.93 and esophagus 0.68; 95% CI 0.23 – 1) and moderate in duodenum (0.55; 95% CI 0.32 – 0.79). The agreement on adequate vs inadequate cleanliness was similar among the Western and Eastern experts (Western: 0.74; 95% CI 0.64 – 0.84 and Eastern: 0.70; 95% CI 0.55 – 0.85) being substantial in both cases. [1]

Conclusions Assessment of mucosal cleanliness of the UGI tract using the PEACE scale shows high concordance for both overall scoring and for identification of adequate cleanliness. This scale allows the implementation of a simple, uniform method to assess and document cleanliness during esophagogastroduodenoscopy (similar to the Boston Bowel Preparation Scale for colonoscopy). The scale being validated among international experts with high concordance, can be used in clinical practice.

Publication History

Article published online:
15 April 2024

• References

• 1 Romańczyk M, Ostrowski B, Lesińska M. et al. The prospective validation of cleanliness in the upper digestive tract according to POLPREP upper gastrointestinal cleanliness scale in reference to endoscopic findings – the VISUAL study Gastrointestinal Endoscopy. 2023 97 06 AB171.