Table 3.
Model | Estimated Mortality Benefit from Transfer to Level I Trauma Center (%) | 95% CI (Bootstrapped with 1,000 Replications, Bias-Corrected) |
---|---|---|
Single-equation probit* | 1.9 | (−3.2%, 6.5%) |
Instrumental variables, bivariate probit† | 10.1 | (0.3%, 22.2%) |
Bivariate probit, reduced covariates model 1‡ | 9.9 | (−2.1%, 20.6%) |
Bivariate probit, reduced covariates model 2§ | 7.3 | (0.1%, 20.3%) |
Bivariate probit, reduced covariates model 3¶ | 12.6 | (1.9%, 26.1%) |
Two-stage, linear probability model† | 7.0 | (0.04%, 13.8%) |
Covariates include: whether the patient was transferred to a level I or level II trauma center; dichotomous variables for children <12 years old and adults >55 years old; gender; a history of comorbid condition(s); whether the patient was transferred within Oregon; log (ISS); Head Abbreviated Injury Scale (AIS) of 5; AVPU score=V; AVPU score=P; AVPU score=U; hypotension in the emergency department (ED).
Covariates include: whether the patient was transferred to a level I or level II trauma center; dichotomous variables for children <12 years old and adults >55 years old; gender; a history of comorbid condition(s); whether the patient was transferred within Oregon; log (ISS); Head AIS of 5; AVPU score=V; AVPU score=P; AVPU score=U; hypotension in the ED. Differential distance is used as the instrumental variable.
Covariates include primarily demographic variables: whether the patient was transferred to a level I or level II trauma center; whether the patient was transferred within Oregon; dichotomous variables for children <12 years old and adults >55 years old; gender; history of comorbid condition(s); log (ISS). Differential distance is used as the instrumental variable.
Covariates include mostly measures of injury severity: whether the patient was transferred to a level I or level II trauma center; log (ISS); AVPU score=V; AVPU score=P; AVPU score=U; hypotension, and head AIS=5; hypotension in the ED. Differential distance is used as the instrumental variable.
Covariates include: whether the patient was transferred to a level I or level II trauma center; dichotomous variables for adults >55 years old; whether the patient was transferred within Oregon; log (ISS); head AIS of 5; AVPU score=U. Differential distance is used as the instrumental variable.