Interrater variability in ASA physical status assignment: an analysis in the pediatric cancer setting

Background The American Society of Anesthesiologists (ASA) physical status is a universal classification system that helps clinicians to categorize their patients preoperatively. However, there is a lack of both inter-rater and intra-rater reliability among clinicians for the ASA physical status classification. Our study focuses on testing these reliabilities within pediatric anesthesia providers in the cancer setting. Methods In our retrospective observational study, a total of 1177 anesthesia records were reviewed. The cohort included all pediatric patients (<= 18 years old) diagnosed with either retinoblastoma or neuroblastoma who had two or more anesthesia procedure within a 14-day time period. Results Overall, the ASA physical status score among two different anesthesia providers for the same patient treated at different times had very little inter-rater reliability, kappa = - 0.042 (95% CI - 0.17; 0.09). Of the 1177-patient anesthesia records, only 25% had two or more ASA physical status score assigned by the same anesthesiologist within a 14-day time period. There was moderate intra-rater reliability kappa = 0.48 (95% CI 0.29; 0.68) for patients who were assigned an ASA physical status score by the identical anesthesia provider at different times points within a 14 day period. Conclusion In contrast to observations in earlier studies, findings indicate poor agreement in inter-rater reliability. Although there was moderate agreement in intra-rater reliability, one would expect to find stronger, even perfect, intra-rater reliability. These findings suggest the need to develop a specific physical status classification system directed toward patients with a systemic illness such as cancer in both young and adult patients.