Table 3.

Instrumental Variable Analysis of the Impact of HSA Resection Rate on Survival for Patients with Pancreatic Ductal Adenocarcinoma

	2SRI IV Model (Cox)		2SLS IV Model
Variable	Hazard Ratio	95% Confidence Interval	Parameter Estimate (change in months survived)	95% Confidence Interval
Pancreatectomy	0.54***	0.39, 0.75	5.54***	2.34, 8.74
Residual Term	0.68*	0.49, 0.94	N/A	N/A
Age	1.02***	1.01, 1.02	−0.13***	−0.17, −0.10
Sex (ref = Female)
Male	1.05	1.00, 1.11	−0.70*	−1.23, −0.17
Race (ref = White)
Black	1.09	1.00, 1.19	−0.49	−1.37, 0.39
Other	0.99	0.89, 1.10	−0.36	−1.40, 0.69
Marital Status (ref = Married)
Divorced	1.18***	1.08, 1.30	−1.35**	−2.27, −0.42
Separated	1.29	0.99, 1.69	−1.77	−4.53, 1.00
Single	1.13**	1.04, 1.24	−1.16*	−2.05, −0.26
Widowed	1.21***	1.12, 1.30	−1.28**	−2.05, −0.50
Unknown	1.08	0.92, 1.27	−0.79	−2.38, 0.80
Tumor Stage (ref = Stage IA)
Stage IB	1.42***	1.20, 1.68	−2.41**	−4.00, −0.83
Stage II NOS	1.80***	1.40, 2.32	−3.71**	−6.27, −1.14
Stage IIA	1.48***	1.27, 1.72	−2.56***	−3.97, −1.15
Stage IIB	1.58***	1.36, 1.84	−3.84***	−5.25, −2.43
County % Below Poverty	1.00	1.00, 1.01	−0.09**	−0.15, −0.03
County % Bachelor’s Degree	0.99***	0.99, 1.00	0.03*	0.0003, 0.07
Model Intercept	N/A	N/A	24.93***	20.33,29.53

^*,**,***indicate parameter estimate associated p-value of <0.05, <0.01, <0.001 respectively.