External validation of the Meggitt-Wagner, Texas University, SINBAD, and Saint Elian classifications for predicting major amputation in patients with diabetes at a public hospital in Peru - Luis Alberto Gallardo-Alburqueque; Yudith Quispe-Landeo; Ann Chanamé-Marín; Leonardo J. Uribe-Cavero; Marlon Yovera-Aldana (PLoS ONE, 2026)