Table 3.
Variation in survival outcomes and proportion of explained variation. The extent of variation is quantified by the median odds ratio (OR). The relative contribution of patient demographics, cardiac arrest characteristics, bystander response (CPR and AED use) and county-level socio-demographic characteristics in explaining variation in survival outcomes was quantified.
| Median OR for county effect (95% CI) | Percent variation explained, % | |
|---|---|---|
| Survival to discharge | ||
| Unadjusted | 1.40 (1.32-1.46) | |
| Adjusted for demographics¶ | 1.38 (1.31-1.45) | 4.8 |
| Adjusted for demographics, and cardiac arrest characteristics§ | 1.33 (1.26-1.39) | 27.7 |
| Adjusted for demographics, cardiac arrest characteristics and bystander response (CPR and AED)δ | 1.29 (1.23-1.35) | 41.0 |
| Adjusted for demographics, cardiac arrest characteristics, bystander response (CPR and AED), and county-level socio-demographic characteristicsϕ | 1.26 (1.20-1.32) | 50.4 |
| Survival with functional recovery | ||
| Unadjusted | 1.53 (1.43-1.62) | -- |
| Adjusted for demographics¶ | 1.50 (1.41-1.58) | 10.9 |
| Adjusted for demographics, and cardiac arrest characteristics§ | 1.44 (1.35-1.51) | 27.7 |
| Adjusted for demographics, cardiac arrest characteristics and bystander response (CPR and AED)δ | 1.40 (1.32-1. 74) | 37.2 |
| Adjusted for demographics, cardiac arrest characteristics, bystander response (CPR and AED), and county-level socio-demographic characteristicsϕ | 1.35 (1.28-1.42) | 49.9 |
Model adjusted for age, sex and race
Model adjusted for age, sex, race, initial rhythm, location, witnessed arrest, calendar year of cardiac arrest
Model adjusted for age, sex, race, initial rhythm, location, witnessed arrest, calendar year of cardiac arrest, bystander CPR and AED use at a patient-level along with county-level rates of bystander CPR and county-level rates of AED
Model adjusted for age, sex, race, initial rhythm, location, witnessed arrest, calendar year of cardiac arrest, bystander CPR and AED use at a patient-level along with county-level rates of bystander CPR, county-level rates of AED, and county-level socio-demographic characteristics (median age, proportion of black residents in the county, proportion of male residents in the county, median household income and population density in 2010