Medical imaging costs at a steady percentage of overall hospital costs

May 24 2005

The substantial increase in the use of medical imaging during recent years has fueled speculation that imaging costs were a major factor behind the rise in overall health care costs.

However, a study from the Institute for Technology Assessment at Massachusetts General Hospital (MGH) has found that imaging costs remained at a steady percentage of overall hospital costs during a six-year period. The report will appear in the June issue of Radiology and has been released on the journal's website.

"There have been several news stories and reports from insurers claiming that imaging costs are catching and even surpassing drug costs as major drivers of health care inflation," says Scott Gazelle, MD, MPH, PhD, an MGH radiologist who is director of the Institute for Technology Assessment and co-author of the Radiology article. "Those of us who work in imaging believe that its use should be celebrated, since imaging has truly transformed the way we deliver health care. But we also need to understand the value that imaging brings to health care; and when looking at its costs, we need to make sure our analyses are accurate."

In order to objectively assess imaging's contribution to hospital costs, Gazelle and his co-author Molly Beinfeld, MPH, analyzed billing records for patients admitted to MGH between 1996 and 2002. They reviewed data on more than 17,000 patients with diagnoses in six areas typically utilizing imaging – stroke, appendicitis, lung cancer, upper gastrointestinal disorders, colon cancer and back pain – and compiled information regarding specific imaging studies that were carried out and their costs.

During the study period, the total number of CT scans and MRI studies more than doubled, reflecting increases in the number of patients in the groups analyzed, how many had imaging studies and the number of studies ordered per patient. However, the contribution of imaging to the overall cost of care for these patients remained steady at about 10 percent.

"We actually expected that imaging would represent a higher percentage of costs, but this result makes it hard to say that imaging is driving increased overall costs," says Gazelle. "A particularly surprising finding suggests that patients with higher imaging costs might have a shorter length of stay, but that observation needs to be confirmed in further studies."

He adds that future research should look at the impact of imaging costs across a broader range of institutions and settings and throughout patients' entire course of care, not just during hospitalization. Gazelle is an associate professor of Radiology at Harvard Medical School.