Development of an Algorithm to Identify Preoperative Medical Consultations Using Administrative Data

606 individuals, aged older than 40 years, who underwent elective intermediate-to-high-risk noncardiac surgery at 8 randomly selected hospitals

Claims-based algorithm (physician service claim for a consultation by a cardiologist, general internist, endocrinologist, geriatrician, or nephrologist within 4 months before the index surgical procedure)

Medical record abstraction

Accuracy of identifying preoperative medical consultations (sensitivity, specificity, positive predictive value, and negative predictive value)