The Accuracy of Interqual Criteria in Determining the Observation versus Inpatient Status in Older Adults with Syncope

Background: McKesson's InterQual criteria are widely used in hospitals to determine if patients should be classified as observation or inpatient status, but the accuracy of the criteria is unknown. Objective: We sought to determine whether InterQual criteria accurately predicted length of stay (LOS) in older patients with syncope. Methods: We conducted a secondary analysis of a cohort study of adults ≥60 years of age who had syncope. We calculated InterQual criteria and classified the patient as observation or inpatient status. Outcomes were whether LOS were less than or greater than 2 midnights. Results: We analyzed 2361 patients; 1227 (52.0%) patients were male and 1945 (82.8%) were white, with a mean age of 73.2 ± 9.0 years. The median LOS was 32.6 h (interquartile range 24.2–71.8). The sensitivity of InterQual criteria for LOS was 60.8% (95% confidence interval 57.9–63.6%) and the specificity was 47.8% (95% confidence interval 45.0–50.5%). Conclusions: In older adults with syncope, those who met InterQual criteria for inpatient status had longer LOS compared with those who did not; however, the accuracy of the criteria to predict length of stay over 2 days is poor, with a sensitivity of 60% and a specificity of 48%. Future research should identify criteria to improve LOS prediction.