Inter-Observer Variability of Gerd-Related Metrics on High-Resolution Manometry and Calculation of the Milan Score.
Sozzi M, Siboni S, Latorre-Rodriguez AR, Mittal SK, Marabotto E, Pasta A, Calabrese F, Andreatta E, Aldinio G, Coletta M, Penagini R, Lee YY, Ehab SAM, Tee V, Lee RH, Alcala-Gonzalez LG, Rogers B, Hennen MS, Haworth J, Patel A, Patel P, Masuda T, Coss-Adame E, Salvador R, Provenzano L, Nicoletti L, Piccirelli S, Pezzuto E, Tolone S, Asti E, Savarino EV, Gyawali CP
Background
High-resolution manometry (HRM) is increasingly used to assess risk of gastroesophageal reflux disease (GERD). The Milan Score (MS) integrates four HRM variables-EGJ morphology, EGJ contractile integral (EGJ-CI), ineffective esophageal motility (IEM), and straight leg raise (SLR) response-to predict pathological esophageal acid exposure. The inter-observer reproducibility of the MS and its components has never been formally assessed.
Methods
A total of 50 consecutive HRM plots from patients undergoing evaluation for suspected GERD at a tertiary referral center were distributed to a multicenter pool of esophageal experts for blind review. Participants assessed EGJ type, EGJ-CI, IEM, and SLR response; the MS and corresponding GERD risk were automatically calculated. Inter-observer variability was evaluated using Fleiss' κ for categorical variables and Kendall's coefficient for continuous variables. MS accuracy was assessed by comparing calculated scores against MII-pH results.
Results
Twenty-three esophageal experts from 16 international institutions reviewed all 50 plots. Agreement was fair for EGJ morphology (κ = 0.321), moderate for SLR (W = 0.531), and good for IEM (κ = 0.638), EGJ-CI (W = 0.675) and the final MS (W = 0.641). Median plot-level concordance between MS and pH-impedance study was 71.74% [IQR 51.08%]; median reader accuracy for Milan Score was 64% [IQR 12%], ranging from 54% to 80%.
Conclusions
Inter-observer variability of the Milan Score is good across a diverse international cohort of esophageal experts, supporting its reproducibility as a clinical tool. However, agreement for individual parameters was heterogeneous, and the assessment of EGJ morphology and the SLR maneuver achieved only fair-to-moderate agreement, highlighting the need for improved standardization.
The Milan Score is a high‐resolution manometry tool that integrates four variables to predict the risk of a pathological esophageal acid exposure: EGJ morphology, EGJ contractile integral, ineffective esophageal motility, and response to the straight leg raise maneuver. Blinded assessment of inter‐observer variability of the score and its components across a diverse international cohort of esophagologists demonstrated a heterogeneous agreement for individual parameters and only fair‐to‐moderate agreement for EGJ morphology and the SLR maneuver, highlighting the need for standardization to improve reproducibility. Nevertheless, the good reproducibility for the final Milan Score supports its use as a clinical tool to assess the risk of GERD.