Table 4.

Adjusted cost ratios before and after the index date

	Before index date			After index date
Healthcare resource	Cost ratioε	95% CI (ROBUST)	P value	Cost Ratioε	95% CI (ROBUST)	P value
Office visits	1.195	0.939 - 1.519	0.147	1.210	0.929 - 1.575	0.157
Outpatient visits	0.855	0.685 - 1.067	0.164	1.490	1.055 - 2.103	0.024
ER visits	0.844	0.627 - 1.136	0.263	1.160	0.830 - 1.624	0.386
Inpatient days	0.844	0.531 - 1.342	0.473	0.906	0.568 - 1.444	0.677
Other services	6.245	3.424 - 11.388	< 0.001	11.834	7.834 - 17.875	< 0.001
Prescription drugsω	0.995	0.782 - 1.267	0.970	1.372	1.087 - 1.731	0.008

ε: Fully adjusted cost ratio; generalized Linear Model (gamma family, log link) adjusted for age category, gender, race, period of COPD diagnosis census region, oxygen use, Charlson Comorbidity Score, and interaction terms: AATD*CCI, AATD*Oxygen use and AATD*Period of COPD diagnosis

ϒ: number of additional visits/IP days/Prescription drugs on a raw scale attributable to the presence of AATD; generalized linear model

Ω: for a subset of patients who had prescription drug coverage through the same payer