Comparing the effects of decreasing prescription opioid shipments and the release of an abuse deterrent OxyContin formulation on opioid overdose fatalities in WV: an interrupted time series study

Table 2 Interrupted time series results of opioid-involved overdoses in West Virginia involving illicit opioids.^a

	3-Month Lag/Transition Period					6-Month Lag/ Transition Period
Intervention: Oxycontin ADF released (2010 Q3)					Intervention: Oxycontin ADF released (2010 Q3)
	Parameter	Estimate	P-value	AIC		Parameter	Estimate	P-value	AIC
	AR1 (𝜖)	0.60	< 0.001	-183.7		AR1 (𝜖)	0.57	< 0.001	-185.6
	Intercept (𝛽₀)	0.21	< 0.001			Intercept (𝛽₀)	0.17	< 0.001
	Ramp (𝛽₂)	0.023	< 0.001			Ramp (𝛽₂)	0.02	< 0.001
Intervention: Peak dosage units (2011 Q3)					Intervention: Peak dosage units (2011 Q3)
	Parameter	Estimate	P-value	AIC		Parameter	Estimate	P-value	AIC
	AR1 (𝜖)	0.50	< 0.001	-188.7		AR1 (𝜖)	0.50	< 0.001	-189.4
	Intercept (𝛽₀)	0.18	< 0.001			Intercept (𝛽₀)	0.18	< 0.001
	Ramp (𝛽₂)	0.02	< 0.001			Ramp (𝛽₂)	0.02	< 0.001
Intervention: Peak MMEs (2012 Q4)					Intervention: Peak MMEs (2012 Q4)
	Parameter	Estimate	P-value	AIC		Parameter	Estimate	P-value	AIC
	AR1 (𝜖)	0.11	< 0.001	-182.9		AR1 (𝜖)	0.67	< 0.001	-180.7
	Intercept (𝛽₀)	0.02	< 0.001			Intercept (𝛽₀)	0.21	< 0.001
	Ramp (𝛽₂)	0.00	< 0.001			Ramp (𝛽₂)	0.02	< 0.001

^a Illicit opioid overdoses were defined as those involving heroin and synthetic opioids other than methadone, including fentanyl, fentanyl analogues, 4-anpp, and u-47,700. Data are from the West Virginia Forensic Drug Database, which compiles data from the West Virginia Office of the Chief Medical Examiner
^b Akaike Information Criteria (AIC). A lower value is considered better model fit and a difference of more than two AIC units indicates a meaningfully better-fitting model

ISSN: 1747-597X