"Surgeons' Intuition" Versus "Prognostic Models" Predicting the Risk of Liver Resections

Objectives: Analyze surgeons' anticipation of the risk of hepatectomy. Background: Risk prediction enables adequate counseling and improves safety. Models are available that predict postoperative morbidity and length of stay (LOS), but their performance is ill-defined. Surgeons' ability to predict these endpoints is unknown. Methods: This prospectively designed, multicenter trial included all adult patients undergoing elective hepatectomy. Primary endpoints were 90-day morbidity and mortality and LOS. Explanatory variables included (i) "surgeons' intuition" (surgeons' anticipation) of the difficulty of the procedure, postoperative morbidity, and LOS and (ii) "prognostic models" (models based on objective clinic-biological variables) available at the time of anticipation. The performance of "surgeons' intuition" and "prognostic models" was assessed by area under the receiver operating characteristic curve and its accuracy by the diagnostic odd ratios. Results: Between October 2012 and September 2013, 946 patients operated on in hepato-pancreatico-biliary units in 9 teaching hospitals by 26 surgeons were enrolled. Mortality, morbidity, and median LOS were 3.3%, 49.4%, and 8 days, respectively. Preoperative surgeons' intuition of difficulty correlated with actual difficulty (Kendall tau = 0.97; P = 0.0001) but not with morbidity (Kendall tau = 0.01; P = 0.0006) or LOS (Kendall tau = 0.10; P = 0.004). Morbidity was predicted accurately in 38.8% of patients and underestimated in 38.2%. Anticipation of LOS was accurate (+/-2 days) in 30.0% and underestimated in 47.1%. The accuracies and performance of preoperative and postoperative "surgeons' intuition" were not different and were not different between centers or surgeons' experience. The accuracy of "prognostic models" was significantly greater than that of anticipations and not improved by adding "anticipations" to the model. Conclusions: Surgeons should be aware of the limited accuracy of their intuition.