Stigmata of hemorrhage in bleeding peptic ulcers: an interobserver agreement study among international experts

Abstract

Background: Stigmata of hemorrhage predict rebleeding and outcome of patients with bleeding peptic ulcers. There are variabilities in reported incidences of stigmata and their respective rebleeding risks. We sought to study the interobserver agreement among experts. Methods: Between June 1994 and July 1994, 100 consecutive patients with bleeding peptic ulcers underwent videoendoscopy within 24 hours of their admissions. An edited videotape of these ulcers was compiled and sent to an international panel of 14 experts. They independently rated these ulcers exclusively into one of the six categories: spurting, oozing, nonbleeding visible vessel, adherent clot, flat pigmented spot, or clean based. Agreement between any two experts was expressed by a kappa estimate (κ). Agreements over individual stigmata and a composite κ estimate (κ w) signifying overall agreement were also computed. Results: Out of the possible 91 pairwise κ estimates among 14 experts, 35 (38.5%) were less than or equal to 0.40, indicating poor agreement. None of the κ estimates was greater than 0.75. Composite κ estimates for individual stigmata were as follows: spurting κ = 0.664, oozing κ = 0.420, nonbleeding visible vessel κ = 0.342, adherent clot κ = 0.426, flat pigmented spot κ = 0.393, and clean-based ulcer κ = 0.371. The weighted κ estimate was 0.426. Conclusion: Agreement between experts was poor in more than a third of occasions. Although the overall interobserver agreement was fair (0.4 < κ < 0.75), agreements for nonbleeding visible vessels, flat pigmented spots, and clean-based ulcers were poor. (Gastrointest Endosc 1997;46:33-6)