U.S. News & World Report on Tuesday released its 27th annual Best Hospitals rankings, with Mayo Clinic topping the publication's "Honor Roll" after coming in second last year.

For this year's list, U.S. News evaluated 4,667 hospitals across 16 specialties and identified 153 hospitals that earned scores high enough to be included in the rankings. The publication also named 20 hospitals to its "Honor Roll" for achieving strong performance in multiple specialties.

How hospitals were ranked

U.S. News ranked four specialties—ophthalmology, psychiatry, rehabilitation, and rheumatology—based only on a reputational survey of specialists.

For those rankings, U.S. News asked physicians in each specialty to list hospitals they considered among the best in their field for difficult cases. Hospitals cited by at least 5 percent of surveyed physicians in a specialty were included in its rankings.

The remaining 12 specialty rankings were largely data-driven and based on survival rates, adverse events, and nurse staffing levels, among other measures. Those 12 specialty rankings also considered a reputational survey of specialists.

To qualify for this year's 12 data-driven lists, hospitals had to be a teaching hospital; be affiliated with a medical school; have at least 200 beds; or have at least 100 beds and offer four or more types of medical technology considered by U.S. News to be key to high-quality care, such as PET/CT scanners.

To achieve a ranking in a specific specialty, hospitals had to meet a volume requirement that included a minimum number of fee-for-service Medicare inpatient discharges for certain procedures and conditions between 2012 and 2014, or hospitals had to have received nominations from at least 1 percent of specialists responding to U.S. News surveys conducted between 2014 and 2016.

The 1,891 hospitals that met those requirements in at least one specialty then received a score between 0 and 100 based on four factors (with the exception of cardiology and heart surgery, which had a slightly different methodology):

• Survival rates within 30 days of admission (37.5 percent);
• Care-related factors such as nurse staffing patient volumes (30 percent);
• Reputation (27.5 percent); and
• Patient safety, based on hospitals' rates of six medical errors or oversights (5 percent).

Cardiology and heart surgery programs also were judged on a fifth factor: public transparency, for publicly reporting quality metrics through American College of Cardiology and the Society of Thoracic Surgery websites. Transparency was weighted at 3 percent, while reputation was weighted at 24.5 percent.

One key to improving quality: Identifying clinical variation

Ben Harder, chief of health analysis at U.S. News, said, "We strive to provide patients with the highest-quality information on hospitals available," adding, "Driving for broader transparency and evaluating hospitals in a comprehensive, fair way reflects that mission."

Honor Roll

U.S. News assembled an "Honor Roll" recognizing 20 facilities that achieved high scores in a range of specialties. This year, U.S. News updated it Honor Roll methodology to deemphasize reputation-based rankings.

The Honor Roll institutions, ranked from one to 20, are:

1. Mayo Clinic (Rochester, Minnesota)
2. Cleveland Clinic
3. Massachusetts General Hospital (Boston)
4. Johns Hopkins Hospital (Baltimore)
5. UCLA Medical Center (Los Angeles)
6. New York-Presbyterian University Hospital of Columbia and Cornell
7. UCSF Medical Center (San Francisco)
8. Northwestern Memorial Hospital (Chicago)
9. Hospitals of the University of Pennsylvania-Penn Presbyterian (Philadelphia)
10. NYU Langone Medical Center
11. Barnes-Jewish Hospital/Washington University (St. Louis)
12. UPMC Presbyterian Shadyside (Pittsburgh)
13. Brigham and Women's Hospital (Boston)
14. Stanford Health Care-Stanford Hospital (Stanford, California)
15. Mount Sinai Hospital (New York)
16. Duke University Hospital (Durham, North Carolina)
17. Cedars-Sinai Medical Center (Los Angeles)
18. University of Michigan Hospitals and Health Centers (Ann Arbor)
19. Houston Methodist Hospital
20. University of Colorado Hospital (Aurora)

Reaction

Mayo Clinic President and CEO John Noseworthy said that his organization is "honored to be recognized in this way, but what truly matters is where it all begins—with our patients, with everyone who looks to Mayo Clinic for hope and healing."

Cleveland Clinic CEO Toby Cosgrove said the rankings, including the Clinic's top ranking for cardiology and heart surgery, are a draw to patients and "a recognition that speaks to the experience and quality of the Cleveland Clinic's cardiac team."

Cosgrove also said there is "a growing frustration amongst hospitals across the country that there are so many different metrics and rating systems" and said he hoped the industry eventually moves toward more standardized assessments of care quality (U.S. News release, 8/2; U.S. News Honor Roll, 8/2; U.S. News FAQ, 8/2; U.S. News methodology, accessed 8/2; Zeltner, Plain Dealer, 8/2; Mayo Clinic website, accessed 8/2).