Author: Guo L et al.
Anesthesiology, September 15, 2025. doi:10.1097/ALN.0000000000005751
This study assessed whether Medicaid anesthesia claims data can reliably approximate anesthesia time, focusing on appendectomy and cholecystectomy cases in beneficiaries under 65. Using 902,492 fee-for-service claims from 48 states and DC (1999–2013), investigators examined the “quantity of service” (QoS) variable as a proxy for anesthesia time. QoS reporting varied: 14 states used units, 19 used minutes, and 16 reported both.
The majority of states demonstrated strong correlations (Spearman >0.7) between QoS values, expected anesthesia times, and Medicaid payments, suggesting usability. Specifically, 64% of unit-reporting states and 74% of minute-reporting states met all validation criteria. However, only about half of the states reporting both formats met criteria for each. Outliers and inconsistent coding were observed, indicating risks of misclassification.
Overall, QoS appears useful for estimating anesthesia time in Medicaid claims but reliability varies across states, requiring careful validation before use in research or policy.
What You Should Know
• Medicaid anesthesia claims contain a QoS variable that can proxy anesthesia time.
• Most—but not all—states’ claims data showed strong validity against expected times and payments.
• Unit-reporting states often used 15-minute blocks, while others reported exact minutes.
• Misclassification and outliers remain a challenge, limiting generalizability.
• Researchers should validate state-specific coding before using QoS as a measure of anesthesia time.
Thank you to Anesthesiology for making this work available.