Table 3.

Results from the Primary Instrumental Variable Analysis Reporting Adjusted Risks of Adverse Events among Patients Hospitalized and Discharged after ED Evaluation for Chest Pain. Risk Reduction Reports the Difference between Hospitalized (Treated) and Discharged (Control) Patients for Comparisons among 30-Day Patient Outcomes

Outcome	Adjusted risk		Risk reduction (RR)	Number needed to treat (NNT)
	Not hospitalized (control) (N= 62,876) Mean (Std error)	Hospitalized (treated) (N= 16,164) Mean (Std error)	Hospitalized adjusted risk- control adjusted risk Mean* (95% CI)	1/Absolute risk reduction
Death/AMI	0.003 (0.001)	0.006 (0.002)	0.002 (−0.002 to 0.007)	N/A^
Death	0.001 (<0.001)	0.001 (0.001)	<0.001 (−0.001 to 0.001)	N/A^
Acute MI	0.002 (<0.001)	0.005 (0.003)	0.003 (−0.003 to 0.010)	N/A^
Coronary revascularization	0.002 (<0.001)	0.002 (0.001)	<−0.001 (−0.002 to 0.001)	N/A^
MACE	0.003 (0.001)	0.006 (0.002)	0.003 (−0.002 to 0.007)	N/A^

^Difference in event rates are not statistically significant at α=0·05 and the 95% CI contains zero

*All models adjusted for age, sex, race, smoking, BMI, insurance type, self and family history of CVD, initial troponin, antidiabetic medication, anticoagulant medication, anti-hyperlipidemia medication, anti-hypertension medication, and Elixhauser comorbidities