SEATTLE, WA — A nationwide hospital safety analysis has found that 11 hospitals in Washington received an "A" grade for preventing medical errors, accidents, injuries and infections, which collectively are the third leading cause of death in America.

However, two hospitals received a "D", although neither hospital is near Puget Suond. A number of other hospitals around Puget Sound - including Harborview Medical Center and St. Joseph's in Tacoma - got "C" grades. The Leapfrog Group released it's bi-yearly hospital safety grades on Tuesday, finding that hospitals overall have improved in reducing the number of avoidable deaths. The group assessed roughly 2,500 hospitals. Of those, 30 percent earned an "A," 28 percent earned a "B," 35 percent a "C," 6 percent a "D" and 1 percent an "F."

"The national numbers on death and harm in hospitals have alarmed us for decades. What we see in the new round of Safety Grades are signs of many hospitals making significant improvements in their patient safety record," Leah Binder, president and CEO of Leapfrog, said in a release. The assessment system assigns school-style letter grades to general acute-care hospitals. The hope is to determine a patient's risk of further injury or infection if they visit a certain hospital.

Here are the hospital grades for facilities around Puget Sound: EvergreenHealth, Kirkland - A Multicare Good Samaritan Hospital, Puyallup - A Overlake Hospital Medical Center, Bellevue - A Swedish Health Services, Issaquah - A Swedish Medical Center Ballard, Seattle - A Swedish Medical Center First Hill, Seattle - A Virginia Mason Medical Center, Seattle - A Northwest Hospital and Medical Center, Seattle - B Providence Regional Medical Center, Everett - B Providence St. Peter, Olympia - B St. Anthony, Gig Harbor - B St. Francis Hospital, Federal Way - B Swedish Edmonds Hospital - B Tacoma General Hospital - B Valley Medical Center, Renton - B Harborview Medical Center - C Highline Medical Center, Burien - C Multicare Allenmore, Tacoma - C Multicare Auburn Medical Center - C St. Clare Hospital, Lakewood - C Among the findings nationally, five hospitals that received an "A" grade for the first time this year previously received an "F" grade, the group said, and 46 hospitals earned an "A" for the first time since the grading system began six years ago.

Leapfrog said its analysis showed 89 hospitals that had previously received "D" or "F" ratings had improved to an "A" this year.

Rhode Island, Hawaii, Wisconsin and Idaho all previously ranked near the bottom of the state rankings with low percentages of "A" hospitals, but now all rank in the top 10.

Here are some of the other findings: The five states with the highest percentage of "A" hospitals this spring are Hawaii, Idaho, Rhode Island, Massachusetts and Virginia

Ten states have hospitals with "F" grades are California, the District of Columbia, Florida, Iowa, Illinois, Maryland, Michigan, Mississippi, New Jersey and New York Leapfrog says you shouldn't refuse emergency care because of a bad safety grade. They're meant to be used as a guide for planned events and a research tool for potential emergencies.