Interpretations of diffusion-weighted MR imaging by radiology residents in the emergency department: is diagnostic performance influenced by the level of residency training?

To evaluate the diagnostic performance of radiology residents' interpretations for diffusion-weighted MR imaging (DWI) in the emergency department at different levels of residency training. A total of 160 patients who underwent DWI with acute neurologic symptoms were included in this retrospective study with an institutional review board approval. Four radiology residents with different training years and one attending neuroradiologist independently assessed the DWI results. Discordances between the results of residents and attending neuroradiologist were classified as follows: false positive (FP) and false negative (FN). We also evaluated the diagnostic performance of four residents according to the reference standard. Overall, the concordance rate was 84.8 %, with a 15.2 % overall discordance rate. There were 83 FN results. The most common misses were small vessel disease (n = 55), acute focal infarction (n = 10), diffuse axonal injury (n = 6), solitary mass (n = 5), extraaxial hemorrhages (n = 3), posterior reversible encephalopathy syndrome (n = 2), and postictal change (n = 2). Fourteen FP results were interpreted as hemorrhage and acute infarction. The 4th year resident exhibited the highest diagnostic performance, and the level of training had a significant influence on the rates of concordance (P < 0.05). Interobserver reliability was good between the interpretations of the residents and the final interpretations of the attending neuroradiologists. The level of resident training had a significant effect on their diagnostic performance, and good interobserver reliability was noted between the results of the residents and attending neuroradiologist.