Change in dispensing of controlled-release oxycodone after reformulation, by participant age and formulation strength
| Strength of oxycodone CR, mg | ARIMA model specification | Form of impact of reformulation | Percent immediate level shift after reformulation (95% CI) | Percent total level shift (95% CI) |
|---|---|---|---|---|
| Participant age < 65 yr | ||||
| 10–30 | (0,1,1)(0,1,0) (12) | Gradual level shift over 6 mo | −2.8 (−4.5 to −1.1)* | −11.1 (−17.2 to −4.6) |
| 40–80 | (0,1,1)(0,1,0) (12) | Gradual level shift over 7 mo | −10.6 (−13.0 to −8.2) | −31.5 (−37.5 to −24.9) |
| Participant age ≥ 65 yr | ||||
| 10–30 | (0,1,1)(0,1,0) (12) | Gradual level shift over 3 mo | −2.9 (−5.1 to 0.0)* | −5.0 (−6.1 to 0.0) |
| 40–80 | (2,1,0)(0,1,0) (12) | Gradual level shift over 7 mo | −2.3 (−6.3 to 2.0) | −8.2 (−21.7 to 7.5) |
Note: ARIMA = autoregressive integrated moving average, CI = confidence interval, CR = controlled release.
↵* Impact lagged by 1 month.