There were 49 distinct findings related to distinct pathology at one motion segment in the 10 exams.
Plus marked variability in the reported interpretive findings and high prevalence of interpretive errors in the radiologist’s reports of an MRI exam of the lumbar spine performed on the same patient at 10 different MRI centers over a short period.
Variability in diagnostic error rates of ten MRI centers performing lumbar spine MRI exams on the same patient within a three week period.
BACKGROUND CONTEXT: In today’s healthcare climate, Magnetic Resonance Imaging (MRI) is often perceived as a commodity – a service where there are no meaningful differences in quality and thus an area in which patients can be advised to select a provider based on price and convenience alone. If this prevailing view is correct, then a patient should expect to receive the same radiological diagnosis regardless of which imaging center he or she visits or which radiologist reviews the examination. Based on their extensive clinical experience, the authors believe that this assumption is not correct and that it can negatively impact patient care, outcomes and costs.
PATIENT SAMPLE: A 63-year old female with a history of low back pain and right L5 radicular symptoms.
METHODS: The complete set of interpretive findings from the 10 study MRI exams were tabulated and compared for variability and errors. Two of the authors, both subspecialist spine radiologists from different institutions, independently reviewed the reference exams and then came to a final diagnosis by consensus. Errors of interpretation in the study exams were considered present if a finding present or not present in the study exam’s report was not present in the reference exams.
RESULTS: Across all 10 study exams there were 49 distinct findings reported related to the presence of a distinct pathology at a specific motion segment. Zero interpretive findings were reported in all 10 study exams and only one finding was reported in nine out of 10 study exams. 32.7% of the interpretive findings appeared only once across all 10 of the study exams’ reports. A global Fleiss’ Kappa statistic, computed across all reported findings, was 0.20±0.06, indicating poor overall agreement on interpretive findings. The average interpretive error count in the study exams was 12.5±3.2 (both false positives and false negatives). The average false negative count per exam was 10.9±2.9 out of 25 and the average false positive count was 1.6±0.9, which corresponds to an average true positive rate (sensitivity) of 56.4%±11.7 and miss rate of 43.6%±11.7.
CONCLUSIONS: This study found marked variability in the reported interpretive findings and a high prevalence of interpretive errors in the radiologists’ reports of an MRI exam of the lumbar spine performed on the same patient at 10 different MRI centers over a short time period. As a result, the authors’ conclude that where a patient obtains their MRI exam and which radiologist interprets the exam may have a direct impact on their radiologic diagnosis, subsequent choice of treatment and clinical outcome.