Health care services and survival rates at small, remote hospitals are significantly worse than at other hospitals, according to a Harvard School of Public Health study published Wednesday.

These smaller hospitals, called critical access hospitals, have less in terms of advanced cardiac capabilities, intensive care units, and digital health records, the study found.

Additionally, in the 30-day period following treatment for heart attacks, congestive heart failure, and pneumonia, patients were 30 to 70 percent more likely to die at critical access hospitals than at other hospitals.

Harvard School of Public Health research fellow Karen E. Joynt led the study, which was published in the Journal of the American Medical Association (JAMA) on Wednesday. The study examined over 2.3 million medical records for Medicare recipients from 2008 to 2009 at 4,738 hospitals across the country. Of these hospitals, critical access hospitals comprise 26.8 percent.

“Because Critical Access Hospitals have been exempted from most national quality improvement efforts, we really knew little about their quality or clinical outcomes prior to this study, and we were most surprised at the magnitude of the differences between CAHs and other hospitals," Joynt said in an email.

Those differences will likely grow as advancements in technology and modern medicine leave these smaller hospitals behind. According to the study, these studies face a lack of resources, which forms one of the biggest hurdles these hospitals must face when trying to deliver care comparable to more urban, well-funded hospitals.

"They are small, isolated, and financially vulnerable, and they serve a population that is getting older and poorer," Joynt said.

Joynt said that heeding the advice of rural health specialists is a move that would help improve care nationwide.

“They are the ones who best understand the challenges these hospitals face and who might have great ideas for how we could address them from the policy standpoint," she said.

—Staff writer Leanna B. Ehrlich can be reached at lehrlich@college.harvard.edu.