Amended reports in surgical pathology and implications for diagnostic error detection and avoidance: a College of American Pathologists Q-probes study of 1,667,547 accessioned cases in 359 laboratories.

OBJECTIVES: To evaluate amended report rates relative to surveillance methods and to identify surveillance methods or other practice parameters that lower amended report rates.
DESIGN: Participants in the 1996 Q-Probes quality improvement program of the College of American Pathologists were asked to prospectively document amended surgical pathology reports for a period of 5 months or until 50 amended reports were recorded. The methods of error detection were also recorded and laboratory and institutional policies surveyed. Four types of amended reports were investigated: those issued to correct patient identification errors, to revise originally issued final diagnoses, to revise preliminary written diagnoses, and to revise other reported diagnostic information that was significant with respect to patient management or prognosis. PARTICIPANTS: Three hundred fifty-nine laboratories, 96% from the United States.
RESULTS: A total of 3147 amended reports in all four categories from a survey of 1,667,547 surgical pathology specimens accessioned during the study period were issued by the participants. The aggregate mean rate of amended reports was 1.9 per 1000 cases (median, 1.5 per 1000 cases). Of these, 19.2% were issued to correct patient identification errors, 38.7% to change the originally issued final diagnosis, 15.6% to change a preliminary written diagnosis, and 26.5% to change clinically significant information other than the diagnosis. Most frequently, a request from a clinician to review a case (20.5%) precipitated the error detection. Although not statistically significant, a higher amended report rate (1.6 per 1000) for all error types was associated with routine diagnostic slide review that was performed after completion of the surgical pathology report. This is compared to rates for institutions that had routine diagnostic slide review of cases prior to finalization of pathology reports (1.2 per 1000) and institutions that had no routine diagnostic slide review (1.4 per 100). Slide review of cases prior to completion of reports lowered the rate of amended reports issued for two types of amended reports: those in which the originally issued final diagnosis was changed and those in which information other than the diagnosis was changed for patient management or prognostic significance. Other laboratory practice variables examined were not found to be associated with the amended report rate.
CONCLUSIONS: There is an association between lower amended report rates and diagnostic slide review of cases prior to completion of the pathology report. The level of case review and type of case mix that is necessary for optimal quality assurance needs further investigation.