In the article “Use of radiographic measurements to diagnose stage B2 preclinical myxomatous mitral valve disease in dogs” (J Am Vet Med Assoc 2020;256:1129–1136), incorrect values are reported in the text for the combined variable of vertebral heart size and vertebral left atrial size (VHS + VLAS) at the cutoff that resulted in maximum specificity and for the positive predictive value (PPV) at that cutoff. The correct value for the VHS + VLAS cutoff that resulted in maximum specificity is 14.75 vertebral body units (VBUs), and the PPV at that cutoff is 93%. The values reported in Table 3 are correct.