Crispin A, et al. – The authors conducted this study to give a web–based calculator predicting complication probabilities of patients undergoing colorectal cancer (CRC) surgery in Germany. While most models demonstrated agreeable discrimination and calibration, this did not preclude overly optimistic or pessimistic individual predictions. One had to understand the basic principles of risk calculation and risk communication to avoid misinterpretation. An e–learning tool outlining the appropriate use of the risk calculator was provided.