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

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.

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.

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, κ = - 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 κ = 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.

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.