Design: Interobserver agreement study using recorded laparoscopy videos
Population: 89 surgeons and trainees rating 30 laparoscopies for suspected appendicitis, Denmark
Primary outcome: Agreement on appendicitis classification and postoperative antibiotics
Effect: Normal vs appendicitis κ 0.72 (0.61–0.84); complex κ 0.66 (0.52–0.80); antibiotics agreement 81% if gangrenous

In a Danish study, 89 surgeons and trainees from seven hospitals watched laparoscopy videos from 30 patients with suspected appendicitis. Each classified the appendix as normal, phlegmonous, gangrenous or perforated and said whether they would give postoperative antibiotics.

Agreement on normal versus inflamed appendix was moderate (κ 0.72, 95% CI 0.61–0.84), and on simple versus complex appendicitis somewhat lower (κ 0.66). Agreement on antibiotics was high for phlegmonous (96%) and perforated (99.7%) appendicitis, but only 81% for gangrenous.

Because the grade written in the operation note drives antibiotics and length of stay, the gangrenous category is where decisions diverge most. A simple versus complex split, with clear criteria, may be more reproducible than four grades.

Describe what you see in the operation note — necrosis, perforation, pus, abscess — not just a grade.
Recognise that gangrenous appendicitis is where surgeons most often disagree about antibiotics.
Agree local criteria for complex appendicitis so postoperative antibiotics are consistent across the team.
Use operative video or photographs in teaching to calibrate trainees' grading.

Why it matters

The intraoperative grade decides antibiotics and discharge, yet it is a judgement with no gold standard.

The statistics, in plain English

Kappa measures agreement beyond chance: 1 is perfect, 0 is no better than chance. Values around 0.6–0.7 are usually called moderate to substantial, meaning surgeons often but not always reach the same call.