Agreement among veterinarians evaluating gross lesions of lungs, livers, and nasal turbinates of pigs

Objective - To evaluate agreement between trained veterinarians and a reference inspector when recording gross lesions of lungs, livers, and nasal turbinates of pigs. Design - Prospective study. Sample Population - 10 veterinarians in workshop 1 and 11 veterinarians in workshop 2. Procedure - Analysis of data obtained from 2 workshops in which veterinarians evaluated fresh tissues (30 lungs and 30 livers) and 100 slides of nasal turbinates previously evaluated by the reference inspector. Veterinarians independently recorded observations of gross lesions. Agreement was evaluated by percentage agreement, kappa or weighted kappa, and sensitivity and specificity, where relevant. Results - Agreement between veterinarians and the reference inspector was excellent for detecting consolidation of lung lobes typical of enzootic pneumonia (κ = 0.81 and 0.87 for workshops 1 and 2, respectively) and white spots on livers (κ = 0.76 and 0.78). Estimates of the extent of consolidation as a proportion of lung volume also agreed closely with reference values. Agreement was closer for veterinarians who had undergone repeated training and evaluation. Agreement was good for detecting nasal turbinate atrophy (weighted κ = 0.63 and 0.68) and was poorest for detecting lesions of pleuritis (κ = 0.39 and 0.44). Clinical Implications - For most of the lesions evaluated, acceptable levels of agreement with reference scores were achieved after training of veterinarians to use standardized methods to record gross lesions. Standardization of veterinarians' recordings of gross lesions should improve the reliability and usefulness of data collected by inspection of slaughtered pigs.