Objectives: There is controversy on the proposed\ud benefits of publishing mortality rates for individual\ud surgeons. In some procedures, analysis at the level of\ud an individual surgeon may lack statistical power. The\ud aim was to determine the likelihood that variation in\ud surgeon performance will be detected using published\ud outcome data.\ud Design: A national analysis surgeon-level mortality\ud rates to calculate the level of power for the reported\ud mortality rate across multiple surgical procedures.\ud Setting: The UK from 2010 to 2014.\ud Participants: Surgeons who performed colon cancer\ud resection, oesophagectomy or gastrectomy, elective\ud aortic aneurysm repair, hip replacement, bariatric\ud surgery or thyroidectomy.\ud Outcomes: The likelihood of detecting an individual\ud with a 30-day, 90-day or in-patient mortality rate of up\ud to 5 times the national mean or median (as available).\ud This was represented using a novel heat-map\ud approach.\ud Results: Overall mortality rates for the procedures\ud ranged from 0.07% to 4.5% and mean/median\ud surgeon volume was between 23 and 75 cases. The\ud national median case volume for colorectal (n=55) and\ud upper gastrointestinal (n=23) cancer resections\ud provides around 20% power to detect a mortality rate\ud of 3 times the national median, while, for hip\ud replacement, this is a rate 5 times the national average.\ud At the mortality rates reported for thyroid (0.08%) and\ud bariatric (0.07%) procedures, it is unlikely a surgeon\ud would perform a sufficient number of procedures in\ud his/her entire career to stand a good chance of\ud detecting a mortality rate 5 times the national average.\ud Conclusions: At present, surgeons with increased\ud mortality rates are unlikely to be detected. Performance\ud within an expected mortality rate range cannot be\ud considered reliable evidence of acceptable\ud performance. Alternative approaches should focus on\ud commonly occurring meaningful outcome measures,\ud with infrequent events analysed predominately at the\ud hospital level.