Table 3.
Estimates of the generalized linear mixed models on the probability of generic and branded substitution
| Generic substitution | Branded substitution | |||
|---|---|---|---|---|
| Log Odds (β) | P-value | Log Odds (β) | P-value | |
| Fixed effects estimates | ||||
| Intercept | 4.262 | < 0.001 | -6.978 | < 0.001 |
| Prescriptions to female patients | -0.163 | 0.284 | 0.095 | 0.391 |
| First prescription in the drug class | -2.582 | < 0.001 | 2.752 | < 0.001 |
| Prescription history | 0.076 | < 0.001 | 0.016 | 0.361 |
| Branded ratio | ||||
| Branded ratio [0 - 0.33) | baseline | |||
| Branded ratio [0.33 - 0.66) | -3.210 | < 0.001 | 2.960 | < 0.001 |
| Branded ratio [0.66 - 1] | -5.952 | < 0.001 | 5.809 | < 0.001 |
| Pharmacy property status | ||||
| Individually owned pharmacy | baseline | |||
| Pharmacy in a partnership | 0.954 | 0.046 | -1.752 | < 0.001 |
| Pharmacy in a chain | 0.687 | < 0.001 | -0.605 | < 0.001 |
| Duration after patent expiry (months) | -0.011 | 0.002 | -0.046 | < 0.001 |
| Age | ||||
| Age [16-31] | baseline | |||
| Age (31-46] | 0.568 | < 0.007 | -0.399 | 0.038 |
| Age (46-52] | 0.546 | 0.012 | -0.146 | 0.307 |
| Age (52-88] | 0.474 | 0.028 | -0.153 | 0.262 |
| Drug group | ||||
| ACE Inhibitors | baseline | |||
| Antidepressants | -0.579 | 0.004 | 1.846 | < 0.001 |
| PPIs | -1.085 | < 0.001 | 0.986 | < 0.001 |
| Statins | 0.574 | 0.001 | -0.634 | < 0.001 |
| Random effects estimates | ||||
| Pharmacy-level residual variance | 1.915 | 0.350 | ||
| Patient- level residual variance | 2.346 | 1.879 | ||
| Somers Dxy criterion | 0.985 | 0.981 | ||