EXHIBIT 2.

Bivariate trends in opioid and benzodiazepine prescription fills, before and after enrollment in the North Carolina Medicaid lock-in program

	Overall		Before enrollment		After enrollment
	Mean, no., %	(SD), %	Mean, no., %	(SD), %	Mean, no., %	(SD), %	Percent change
Mean per person per month fills
Total	2.56	(2.06)	2.72	(2.13)	2.26	(189)	−17
Covered by Medicaid	2.07	(186)	2.43	(1.94)	1.39	(1.50)	−43
Circumvented	0.50	(113)	0.30	(0.85)	0.87	(1.45)	195
Mean pharmacies used per person per month	0.99	(0.81)	1.18	(0.87)	0.64	(0.52)	−46
No. of subjects with any circumvented fills	1,566	95%	1,337	81%	1,436	87%	7
Percent of person-months with any circumvented fills	26.1		17.6		42.3		140

SOURCEAuthors’ analysis of data from the North Carolina Medicaid program and the North Carolina Controlled Substances Reporting System. NOTES“Circumvented” fills were defined as opioid analgesic or benzodiazepine prescription fills purchased from a community pharmacy in North Carolina and paid for entirely out of pocket despite the purchaser’s having Medicaid coverage. All bivariate associations comparing measures before and after lock-in enrollment were significant (p < 0.001). There were 33,882 person-months observed in the period before lock-in enrollment and 17,916 person-months observed after lock-in enrollment. SD is standard deviation.