Table 2. Baseline Characteristics by Cohortsa.
| Characteristic | Within 2 d of ED Presentation | Within 30 d of ED Presentation | Weekday Patients (n = 571 988) |
Weekend Patients (n = 354 645) |
||
|---|---|---|---|---|---|---|
| No Testing (n = 779 012) |
Testing (n = 147 621) |
No Testing (n = 701 660) |
Testing (n = 224 973) |
|||
| Age, yb,c | 43.2 | 50.3 | 42.6 | 49.7 | 44.4 | 44.3 |
| Femaleb,c | 58.8 | 53.1 | 59.6 | 52.5 | 57.9 | 57.7 |
| Chronic kidney disease | 2.1 | 1.5 | 2.1 | 1.6 | 2.0 | 2.0 |
| Diabetes | 14.4 | 17.9 | 14.2 | 17.5 | 15.0 | 14.9 |
| Hyperlipidemiab,c | 31.8 | 44.1 | 30.6 | 43.4 | 33.8 | 33.6 |
| Hypertensionb,c | 39.1 | 48.4 | 38.2 | 47.8 | 40.7 | 40.3 |
| Ischemic heart disease | 4.7 | 4.7 | 4.5 | 5.2 | 4.7 | 4.7 |
| Peripheral vascular disease | 3.5 | 3.0 | 3.4 | 3.3 | 3.4 | 3.4 |
| Smoking history | 10.5 | 8.2 | 10.7 | 8.4 | 10.2 | 10.0 |
| Acute myocardial Infarction, previous year | 1.4 | 1.5 | 1.1 | 1.4 | 1.5 | 1.4 |
| Coronary angiography, previous year | 4.8 | 3.7 | 4.8 | 4.2 | 4.7 | 4.6 |
| Coronary revascularization, previous yeard | 2.0 | 2.6 | 1.8 | 2.9 | 2.1 | 2.1 |
| Cardiologist evaluation, previous year | 8.6 | 6.7 | 8.6 | 7.4 | 8.3 | 8.3 |
| Cerebrovascular accident, previous year | 4.1 | 3.6 | 4.1 | 3.9 | 4.1 | 4.1 |
| Noninvasive test, previous year | 12.8 | 12.4 | 13.1 | 11.8 | 12.8 | 12.7 |
| Antihyperlipidemic treatmentb,c,e | 15.8 | 23.7 | 15.1 | 23.2 | 17.2 | 16.9 |
| Antiplatelet treatmentc,f | 3.6 | 5.1 | 3.4 | 5.4 | 3.9 | 3.7 |
| Primary beneficiaryb,c,g | 63.5 | 70.2 | 62.9 | 69.7 | 65.2 | 63.5 |
| Total follow-up, dh | 291.6 | 294.8 | 290.6 | 297.1 | 292.2 | 292.1 |
Population of 926 633 patients divided into testing cohorts (no testing vs cardiac testing) in noninstrumented analysis and day of presentation cohorts (weekday and weekend patients) in instrumental variable analysis. Data are given as percentages.
Cohen d > 0.1 for standardized mean difference between testing within 2 days of ED visit and no testing within 2 day. Cohen d < 0.1 for standardized mean differences between weekday and weekend patients for all variables.
Cohen d > 0.1 for standardized mean difference between testing within 30 days of ED visit and no testing within 30 days. Cohen d < 0.1 for standardized mean differences between weekday and weekend patients for all variables.
Includes both percutaneous coronary intervention and coronary artery bypass graft surgery.
Claims for all medications in the therapeutic class of antihyperlipidemic drugs in the year preceding ED presentation.
Claims for aspirin or clopidogrel in the year preceding ED presentation.
Indicates whether patient is primary beneficiary of the insurance plan (as opposed to a dependent).
Number of days from the ED visit with enrollment in the health plan.