Validation of a novel hernia recurrence grading classification system: a surgeon survey using clinical vignettes

Hernia recurrence following ventral hernia repair (VHR) is the primary outcome reported across the hernia surgery literature, yet it has historically been described as a binary, dichotomous variable - present or absent - without accounting for its clinical severity, symptom burden, or impact on quality of life. Our group previously published a novel grading classification for hernia recurrence (Grades 0 through VI) designed to standardize the nomenclature and provide a clinically meaningful framework for evaluating recurrence after VHR. To advance this classification toward widespread use, external validation is essential.

We designed a web-based survey instrument consisting of 26 standardized clinical vignettes, each constructed to correspond to a single, unambiguous grade within the Hernia Recurrence Grading System. Respondents were asked to assign the most appropriate grade (0, IA, IB, IIA, IIB, III, IV, V, or VI) to each scenario. The survey was distributed to practicing abdomninal wall surgery specialists. A total of 39 respondents completed the survey. Accuracy was defined as agreement with the a priori correct classification grade for each vignette, and overall concordance rates were calculated.

Thirty-nine respondents completed the survey, generating 1,014 individual responses across 26 vignettes. The overall concordance rate was 90.5% (918/1,014), with a mean per-vignette accuracy of 90.5% (median 93.6%; range 53.8%-100.0%). Fleiss' kappa was 0.815, indicating almost perfect inter-rater agreement. Three vignettes achieved 100% accuracy, and seventeen of twenty-six (65.4%) met a 90% concordance threshold. The highest grade-level accuracy was observed for Grades IV (97.4%), 0 (96.6%), IIB (96.6%), and III (95.7%). The lowest mean grade-level accuracy was Grade IB (73.5%), driven by a single outlier vignette (53.8%). The predominant misclassification patterns involved adjacent-grade confusion between Grades IB and IIA (21 errors) and between Grades IIA and IIB (16 errors).

This surgeon survey using standardized clinical vignettes provides initial evidence supporting the usability and inter-rater comprehensibility of the Hernia Recurrence Grading System. These findings represent an important step toward prospective multicenter validation of the classification and its integration into hernia registry reporting and clinical trial outcome definitions.