Some surgeons' patients have much higher rates of deaths and other bad outcomes than other surgeons'. This shows the percentage of bad outcomes for the best-performing one-tenth of surgeons, the average surgeon, and the worst performing one-tenth of surgeons.

Surgeons receive the following ratings based on our definitions, methods, and analysis of the cases we used/studied from a set of five years of hospital records (see also "Advice & Explanations"):

☆☆☆☆☆ Five stars indicates that, using our analysis methods, a surgeon has met two criteria (1) based on the surgeon's outcomes and number of cases, we can be at least 95 percent confident that his/her better-than-average outcomes were not just the result of good luck; and (2) the surgeon's outcome rates were among the best 1/5th of all surgeons studied.

☆☆☆☆ Four stars indicates that, using our analysis methods, while the surgeon did not meet our criteria to qualify for a 5 star rating, the surgeon performed better than average and based on the surgeon's outcomes and number of cases, we can be at least 90 percent confident that his/her better-than-average outcomes were not just the result of good luck.

☆☆☆☆ Three and a half stars indicates that, using our analysis methods, the surgeon's outcome rates were among the best 1/5th of all surgeons studied but the surgeon did not have enough cases that we can be at least 90 percent confident that his/her better-than-average outcomes are not just the result of good luck.

☆☆☆ Three stars indicates that, using our analysis methods, (1) the surgeons' rates were not among the best 1/5th of all surgeons studied and (2) neither can we be 90 percent confident that the surgeon had better-than-average outcomes that were not just the result of good luck and nor can we be 95 percent confident that the surgeon had worse-than-average outcomes that were not just the result of bad luck.

☆☆ Two stars indicates that, using our analysis methods, while the surgeon did not meet our criteria to get a 1 star rating, the surgeon's outcomes were worse than average and, based on the surgeon's outcomes and number of cases, we can be at least 95 percent confident that his/her worse-than-average outcomes were not just the result of bad luck.

☆ One star indicates that, using our analysis methods, a surgeon has met two criteria (1) based on the surgeon's outcomes and number of cases, we can be at least 95 percent confident that his/her worse-than-average outcomes were not just the result of bad luck; and (2) the surgeon's outcome rates we calculated were among the worst 1/5th of the rates we calculated for all surgeons studied.

— A dash mark indicates that the surgeon did not have enough of this type of surgeries in the records we were able to analyze to provide a basis for us to report on their outcomes.