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Background: The Wellness Ready Test (WRT) 1 is a stable-side lateral-flow test for measuring blood insulin concentrations in equids. The assay has been validated and compared with a radioimmunoassay used commercially in the USA. A method comparison with insulin assays commonly used in the UK has not been reported and would facilitate clinical application of the WRT. Objectives: To compare the results of WRT insulin analysis with the Immulite chemiluminescent immunoassay (ICLIA) 2 and the Tosoh immunofluorescent assay (TIFA) 3. Study Design: Method comparison. Methods: Basal insulin concentrations were analysed from clinical cases for routine diagnosis (ICLIA). Residual blood was used for comparative analysis using the WRT and TIFA. To account for the WRT’s restricted range (20 – 99.9 µIU/mL), data were reformatted, with ICLIA and TIFA values restricted to the same range. Continuous data were analysed using Lin’s concordance correlation coefficients (CCC) and Pearson’s r values. Clinically relevant WRT cut-offs for laminitis risk were derived by ROC analysis compared with the reference method (TIFA). Continuous insulin data were categorised using method-specific laminitis risk cut-offs. Cohen’s kappa coefficient is reported for the inter-method agreement of categorical insulin data. Results: 59 samples were analysed. Concordance between testing methods was strong; WRT/TIFA CCC 0.90 (95% CI 0.86-0.95), Pearson’s r 0.93, p<0.001, WRT/ICLIA CCC 0.84 (95% CI 0.76-0.91), Pearson’s r 0.85, p<0.001. Derived cut-offs for WRT basal insulin values were low risk < 22.2µIU/ml, high risk > 48.3µIU/ml. Cohen’s kappa coefficient for laminitis risk categories for WRT and TIFA was substantial at 0.79 (p<0.001), but moderate for WRT and ICLIA at 0.67 (p<0.001). Main limitations: Limited data from a single hospital and a restricted readable range on the WRT. Conclusions: The WRT shows substantial agreement with established laboratory-based insulin assays in the UK. Results support the stable-side use of the WRT in UK equine practice.