Table 3: Sensitivity, specificity, and predictive values for claims-based administrative ICD code combinations to identify sleep disorders (includes any ICD code identifying a sleep disorder).

Data presented as %. *At least noted number of the relevant ICD diagnostic code appearance in the noted database; ID - Index date (Sleep clinic visit date, the date recorded in the medical record review as the date patient was consulted in the sleep clinic); y - year(s); PC - Practitioners’ Claims Database (Physician Claims); DAD - Discharge Abstract Database (inpatient hospital discharge); NACRS - National Ambulatory Care Reporting System (emergency department/ambulatory care); Sn - Sensitivity; Sp - Specificity; PPV - Positive Predictive Value; NPV - Negative Predictive Value

Administrative datadiagnosis definition	Timing of ICD code appearance
	2 y prior to ID				1 y prior to ID				2 y prior and 1 y post ID
	Sn	Sp	PPV	NPV	Sn	Sp	PPV	NPV	Sn	Sp	PPV	NPV
1 PC	36.0	71.6	90.4	13.1	33.3	73.0	90.2	12.9	79.2	28.4	89.1	15.6
1 DAD	1.7	98.6	90.0	11.9	1.4	98.6	88.2	11.9	2.3	98.6	92.3	12.0
1 PC or 1 DAD	36.6	71.2	89.3	14.5	34.0	71.8	88.8	14.1	79.7	28.8	88.1	17.7
2 PC or 1 DAD	15.3	85.9	87.8	13.3	13.1	90.4	90.0	13.6	43.0	66.7	89.5	15.1
3 PC or 1 DAD	8.6	92.3	88.1	13.3	6.2	94.2	87.7	13.2	23.8	82.1	89.7	14.0
1 NACRS	12.7	90.8	91.1	12.3	7.9	96.5	90.8	12.4	85.4	20.6	88.8	15.9
2 NACRS	8.2	95.7	93.5	12.3	7.9	96.5	94.3	12.4	71.9	54.6	92.1	20.8
3 NACRS	4.6	99.3	98.0	12.3	4.4	99.3	97.9	12.3	45.6	89.4	97.0	18.2
1 PC or 1 NACRS	38.3	68.8	90.1	13.1	35.7	70.5	88.9	14.2	90.8	15.6	88.9	18.6
1 PC or 1 NACRS or 1 DAD	38.9	68.9	89.1	14.5	36.3	69.2	88.6	14.1	91.0	15.4	87.7	20.5