Table 3 The results of interrupted time series analysis for DDDc
Categories | Constant β0(Yt0) | Secular trend β1(Yt1) | Level change β2(Yt2) | Trend change β3(Yt3) |
|---|---|---|---|---|
Drugs under the same generic name | ||||
Bid-winning drugs | 28.20*** (29.99) | -0.59* (24.64) | -7.12*** (15.25) | 0.56* (13.84) |
Generic drugs | 25.04*** (25.54) | 0.03 (25.21) | -7.62*** (19.55) | 0.05 (18.32) |
Branded drugs | 82.04*** (80.92) | -1.65*** (72.60) | -3.08* (57.21) | 1.54*** (56.57) |
Total | 46.72*** (46.61) | -0.89*** (41.69) | -3.01**(31.17) | 0.60** (30.53) |
Alternative drugs under different generic names | ||||
Perfect clinical equivalence | 9.31*** (9.32) | 0.00 (9.33) | 0.03 (9.33) | -0.05* (9.13) |
Fundamental clinical equivalence | 26.91*** (26.61) | -0.05* (26.60) | -6.02*** (20.34) | 0.02 (20.12) |
Limited clinical equivalence | 49.41*** (49.02) | -0.17** (48.37) | 0.65 (48.39) | 0.14 (47.61) |
Total | 40.12*** (39.78) | -0.13** (39.36) | -1.28** (37.59) | 0.09 (37.01) |