Evaluating the Prognostic Accuracy of AMPREDICT in Predicting 1-Year Mortality Following Major Lower Limb Amputation

Accurately predicting postoperative outcomes is fundamental to informed clinical decision-making, and alignment of patient and family expectations. The AMPREDICT Decision Support Tool is a predictive tool designed to assess the probability of mortality 1 year after major and minor amputations. We aimed to evaluate the prognostic accuracy of AMPREDICT in our Veteran patient population. Retrospective review of lower extremity amputations completed at the West Los Angeles Veterans Affairs hospital from 2000 to 2020. Staged open amputations and previous minor amputations were excluded. Using the AMPREDICT tool, the probability of mortality 1 year postsurgery for single-stage transfemoral and transtibial amputations was calculated, then compared with observed patient outcomes. Observed to predicted mortality was compared through boxplots, at 1 year after surgery, confidence intervals were calculated, and group means were compared using Student’s t-test. Receiver operator curves were constructed to assess discriminatory capacity of the tool. Significance was set at P