Proposal for Development of EBM-CDSS (Evidence-Based Clinical Decision Support System) To Aid Prognostication in Terminally Ill Patients

Background: Pancreatic adenocarcinoma is uniformly fatal without operative intervention. Resection can prolong survival in some patients; however, it is associated with significant morbidity and mortality. Regret theory serves as a novel framework linking both rationality and intuition to determine the optimal course for physicians facing difficult decisions related to treatment. Methods: We used the Cox proportional hazards model to predict survival of patients with pancreatic adenocarcinoma and generated a decision model using regret-based decision curve analysis, which integrates both the patient’s prognosis and the physician’s preferences expressed in terms of regret associated with a certain action. A physician’s treatment preferences are indicated by a threshold probability, which is the probability of death/survival at which the physician is uncertain whether or not to perform surgery. The analysis modeled three possible choices: perform surgery on all patients, never perform surgery, and act according to the prediction model. Results: The records of 156 consecutive patients with pancreatic adenocarcinoma were retrospectively evaluated by a single surgeon at a tertiary referral center. Significant independent predictors of overall survival included preoperative stage (p=0.005, CI 1.19-2.27), vitality (p<0.001, CI 0.96-0.98), daily physical function (p<0.001, CI 0.97-0.99) and pathologic stage (p<0.001, CI 3.06-16.05). Compared with the “always aggressive” or “always passive” surgical treatment strategies, the survival model was associated with the least amount of regret for a wide range of threshold probabilities. Conclusions: Regret-based decision curve analysis provides a novel perspective for making treatment-related decisions by incorporating the decision maker’s preferences expressed as his/her estimates of benefits and harms associated with the treatment considered.