Long-term risk prediction after major lower limb amputation: 1-year results of the PERCEIVE study

Background Decision-making when considering major lower limb amputation is complex and requires individualized outcome estimation. It is unknown how accurate healthcare professionals or relevant outcome prediction tools are at predicting outcomes at 1-year after major lower limb amputation.Methods An international, multicentre prospective observational study evaluating healthcare professional accuracy in predicting outcomes 1 year after major lower limb amputation and evaluation of relevant outcome prediction tools identified in a systematic search of the literature was undertaken. Observed outcomes at 1 year were compared with: healthcare professionals' preoperative predictions of death (surgeons and anaesthetists), major lower limb amputation revision (surgeons) and ambulation (surgeons, specialist physiotherapists and vascular nurse practitioners); and probabilities calculated from relevant outcome prediction tools.Results A total of 537 patients and 2244 healthcare professional predictions of outcomes were included. Surgeons and anaesthetists had acceptable discrimination (C-statistic = 0.715), calibration and overall performance (Brier score = 0.200) when predicting 1-year death, but performed worse when predicting major lower limb amputation revision and ambulation (C-statistics = 0.627 and 0.662 respectively). Healthcare professionals overestimated the death and major lower limb amputation revision risks. Consultants outperformed trainees, especially when predicting ambulation. Allied healthcare professionals marginally outperformed surgeons in predicting ambulation. Two outcome prediction tools (C-statistics = 0.755 and 0.717, Brier scores = 0.158 and 0.178) outperformed healthcare professionals' discrimination, calibration and overall performance in predicting death. Two outcome prediction tools for ambulation (C-statistics = 0.688 and 0.667) marginally outperformed healthcare professionals.Conclusion There is uncertainty in predicting 1-year outcomes following major lower limb amputation. Different professional groups performed comparably in this study. Two outcome prediction tools for death and two for ambulation outperformed healthcare professionals and may support shared decision-making.This manuscript reports the 1-year results from the PERCEIVE study. We aimed to evaluate the accuracy of healthcare professionals (surgeons, anaesthetists and allied healthcare professionals) in predicting outcomes at 1 day following a major lower limb amputation and evaluate the accuracy of relevant amputation-specific risk prediction tools in a prospective cohort of patients undergoing major lower limb amputation. Our findings show that healthcare professionals were reasonably accurate in predicting the risk of death but were poor at predicting revision surgery and ambulation. We demonstrate that two death outcome prediction tools outperformed healthcare professionals. Two outcome prediction tools aiming to predict ambulation performed better than healthcare professionals, but estimations were still poor.