Sensitivity and specificity of the EHR-based OSA case definition of two or more ICD-9/ICD-10 diagnostic codes related to OSA is shown overall and at each participating site as a function of PPV, NPV and assumed prevalence. EHR = electronic health record, ICD =, International Classification of Diseases, KPSC = Kaiser Permanente Southern California, NPV = negative predictive value, OSA = obstructive sleep apnea, Penn = University of Pennsylvania, PPV = positive predictive value.