Appropriateness criteria for outpatient CT, MR have room for improvement
CHICAGO—In evaluating the appropriateness of outpatient CTs and MRIs referred from primary care clinics at an academic medical center, researchers found that 26 percent do not meet appropriateness criteria, according to a paper presented Wednesday at the 94th annual meeting of the Radiological Society of North America (RSNA).

Bruce Lehnert, MD, from the department of radiology at the University of Washington in Seattle, who presented the research during the ISP: Health Services, Policy and Research session, said that the purpose of the IRB-approved, HIPPAA-compliant study was to retrospectively analyze a large group of CT and MRI exams for appropriateness using evidence-based guidelines.     

According to Lehnert, researchers reviewed medical records from 462 elective outpatient CT and MR exams: 286 were CT and 176 were MRI. Evidence-based appropriateness criteria from a national radiology benefit company (HealthHelp) were used to determine if the exam would have met criteria for approval.

Radiology reports were examined for the clinical history obtained at the time of interpretation, without looking at the impression or diagnosis. “If the radiology report did not provide enough clinical content, the clinic notes and lab results preceding the date of the imaging study were examined to add further information, simulating a real-time consultation with the referring provider,” he said.

Of the 462 exams, 74 percent were considered appropriate based upon evidence-based appropriateness criteria, and 26 percent were not considered appropriate based upon the information available from the medical record. Lehnert said that of the modality exams analyzed, “CT of the head stood out the most as considered not appropriate” at 66 percent. Of the 184 CTs of the chest or abdomen, 17 percent were considered not appropriate. Of the 158 MRI of brain, spine, shoulder and knee, 25 percent were not appropriate, the authors noted.

Examples of inappropriate exams include brain CT for chronic headache; lumbar spine MR for acute back pain without radiculopathy; knee or shoulder MRI in patients with obvious osteoarthritis; CT chest to follow pneumonia with a normal chest x-ray; and CT for hematuria during a urinary tract infection.

Lehnert said that the results revealed opportunities for improvement in evidence-based appropriateness criteria for imaging and that an intervention with web-enabled clinical decision support is being considered.

“A high percentage of exams not meeting appropriateness criteria suggests a crucial need for tools to help primary care physicians improve the quality of their imaging decisions,” he concluded.