Table 3. Association between opioid-related payments and Medicare Part D opioid prescribing for physicians that received payments in 2015, but not in 2013 and 2014.

	Mean Annual Expenditures for Dispensed Opioids Under Medicare Part D*#	Mean Annual Daily Doses for Dispensed Opioids Under Medicare Part D#	Mean Annual Expenditures per Daily Dose for Dispensed Opioids Under Medicare Part D* #
Payment-receiving physicians (n = 8,669)
Pre-Intervention Period (2013 and 2014)	$20,552	10,624	$1.91
Post Intervention Period (2015)	$21,910	10,906	$1.98
Comparison physicians (n = 153,723)
Pre-Intervention Period (2013 and 2014)	$20,498	9,941	$2.12
Post Intervention Period (2015)	$20,826	9,666	$2.12
Difference-in-differences estimate	$1,031	557	$0.06
SE	219	71	0.03
95% CI	(603–1,460)	(417–697)	(0.002–0.13)
p-Value	<0.0001	<0.0001	<0.0441

Notes

* Adjusted for differences in prices over time ($ 2015).

# Adjusted for average risk scores of beneficiaries treated by each provider.