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 1 Interrupted time series results of opioid-involved overdoses in West Virginia involving prescription 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)	0.36	0.002	-183.1		AR1 (𝜖)	0.32	0.007	-185.5
	Intercept (𝛽₀)	0.27	< 0.001			Intercept (𝛽₀)	0.28	< 0.001
	Time (𝛽₁)	0.02	< 0.001			Time (𝛽₁)	0.02	< 0.001
	Ramp (𝛽₂)	-0.03	< 0.001			Ramp (𝛽₂)	-0.03	< 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)	0.25	0.042	-189.2		AR1 (𝜖)	0.25	0.042	-188.6
	Intercept (𝛽₀)	0.31	< 0.001			Intercept (𝛽₀)	0.32	< 0.001
	Time (𝛽₁)	0.01	< 0.001			Time (𝛽₁)	0.01	< 0.001
	Ramp (𝛽₂)	-0.03	< 0.001			Ramp (𝛽₂)	-0.03	< 0.001
Intervention: Peak MMEs (2012 Q4)					Intervention: Peak MMEs (2012 Q4)
	Parameter	Estimate	P-value	AIC		Parameter	Estimate	P-value	AIC
	AR1 (𝜖)	0.38	0.001	-181.6		AR1 (𝜖)	0.43	< 0.001	-178.3
	Intercept (𝛽₀)	0.35	< 0.001			Intercept (𝛽₀)	0.36	< 0.001
	Time (𝛽₁)	0.01	< 0.001			Time (𝛽₁)	0.01	< 0.001
	Ramp (𝛽₂)	-0.03	< 0.001			Ramp (𝛽₂)	-0.03	< 0.001

^a Prescription opioid overdoses were defined as those associated with oxycodone or hydrocodone. 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