Sources of error in neuropathology intraoperative diagnosis.
OBJECTIVE
The goal of this study was to optimize intraoperative neuropathology consultations by studying trends and sources of diagnostic error. We hypothesized that errors in intraoperative diagnoses would have sampling, technical, and interpretive sources. The study also audited diagnostic strengths, weaknesses and trends associated with increasing experience. We hypothesized that errors would decline and that the accuracy of "qualified" diagnoses would improve with experience.


METHODS
The pathologist's first 100 cases (P1), second 100 (P2), and most recent 100 (P3, after ten years in practice) formed the data set. Intraoperative diagnoses were scored as correct, minor error or major error using the final diagnosis as the gold-standard. Incorrect diagnoses were re-examined by two reviewers to identify sources of error.


RESULTS
Among the 300 cases there were 22 errors with 11 in P1, 9 in P2 and 2 in P3. Sampling contributed to 17 errors (77%), technical factors to 7 (32%) and interpretive factors to 16 (73%). Improvement in diagnostic accuracy between P1 and P2 (p = 0.8143), or P2 and P3 (p = 0.0582) did not reach significance. However, significant improvement was found between P1 and P3 (p = 0.0184).


CONCLUSIONS
The present study was a practical and informative audit for the pathologist and trainees. It reaffirmed the accuracy of intraoperative neuropathology diagnoses and informed our understanding of sources of error. Most errors were due to a combination of sampling, technical and interpretive factors. A significant improvement in diagnostic proficiency was observed with increasing experience.
Department of Epidemiology and Biostatistics, Schulich School of Medicine and Dentistry, University of Western Ontario, London Health Sciences Centre, London, Canada.
Matthew
M
Meyer
Julia
J
Keith-Rokosh
Hasini
H
Reddy
Joseph
J
Megyesi
Robert R
RR
Hammond
D001921:Brain / Q000473:pathology* / Q000601:surgery; D003951:Diagnostic Errors / Q000706:statistics & numerical data*; D006801:Humans; D010340:Pathology, Surgical / Q000379:methods*; D012189:Retrospective Studies; D013997:Time Factors