Two groups have come out with free ratings tools that allow consumers to search online for surgeons who perform major types of operations. (iStock)

One of the most frustrating experiences for patients is choosing a doctor for surgery.

Now two groups have come out with free ratings tools that allow people to search online for surgeons performing several major types of operations. One consumer group compiled a database that lists only top performers. The second, ProPublica, an investigative journalism group, includes information on poor performers.

Consumers’ Checkbook/Center for the Study of Services has created a Web site — it can be seen at www.surgeonratings.org — that allows people to type in a Zip code and search as far as 500 miles away for top-performing surgeons in 14 types of major surgery.

They include heart valve and bypass surgery; total knee and hip replacement; and gastric, hernia and spine-fusion surgery.

The ratings are based on Medicare claims data used to pay doctors and hospitals from 2009 to 2012. They include more than 4 million surgeries performed by more than 50,000 doctors.

Using star ratings (five stars being the best), the group identified surgeons with better-than-average performances based on three criteria:

• Death rates.

• Other bad outcomes, such as infections, falls or other complications that resulted in longer hospital stays or readmissions.

• Recommendations by other doctors, based on the group’s survey of all actively practicing doctors in the same region.

Consumers’ Checkbook publishes many consumer guides, including one that rates top doctor specialists in more than 50 metropolitan regions and another that rates more than 4,500 acute-care hospitals.

“We chose this time to focus on the good ones and to tell people who they are,” said Robert Krughoff, Checkbook’s president.

Some doctors aren’t listed because Checkbook included only those who had performed enough surgeries to provide statistically meaningful comparisons. Giving a surgeon a five-star rating, for example, means the nonprofit is 97.5 percent sure that the surgeon’s performance is better than the average U.S. surgeon.

The ratings take into account how frail or sick the surgeons’ patients were. Even after this adjustment, however, results varied dramatically.

For heart valve and heart bypass surgery, the patients of the best-performing one-tenth of surgeons had death rates of less than 3 percent in the hospital or within 90 days of discharge, compared with death rates of more than 11 percent for patients of the worst-performing one-tenth of surgeons.

ProPublica focused on eight common elective surgeries, including knee and hip replacements and three types of spinal fusions.

Its Surgeon Scorecard, viewable at projects.propublica.org/surgeons, is also based on Medicare billing records. The database calculated death and complication rates for nearly 17,000 surgeons operating at more than 3,500 hospitals. The group analyzed 2.3 million hip and knee replacements, spinal fusions, gallbladder removals, prostate resections and prostate removals done on Medicare patients between 2009 and 2013.

ProPublica consulted with two dozen physicians to identify complications directly related to each of the operations. These include infections, blood clots, misaligned orthopedic devices and uncontrolled bleeding. The group counted only cases in which the patient died in the hospital or had a complication requiring readmission within 30 days.

The database also adjusts for differences in patient health, age and hospital quality.

Consumers can look up a hospital and see how its surgeons compare to each other. They can also search for surgeons by name to learn which procedures they performed, how many times and where, as well as how many complications were involved. Consumers can also review a listing of all the surgeons in a state who perform a particular type of operation.

Overall complication rates were relatively low, the group found, ranging from 2 percent to 4 percent, depending on the type of surgery. But it found that nearly 800 surgeons who each did at least 50 operations did not record a single complication in the five years covered by the analysis.