Table 2 Determinants of generics use (logistic regression)
From: Determinants of generic drug substitution in Switzerland
| Â | Model A Cantons and patients variables | Model B Model A + substitution groups dummies | Model C Model A + substitution groups variables |
|---|---|---|---|
| Â | Coeff. [95%CI] | Coeff. [95%CI] | Coeff. [95%CI] |
CANTON: | Â | Â | Â |
   Aargau (reference) |  |  |  |
   Vaud | -0.253 [-0.31,-0.20] | -0.247 [-0.31,-0.19] | -0.248 [-0.31,-0.19] |
   Ticino | -1.391 [-1.46,-1.32] | -1.459 [-1.53,-1.39] | -1.463 [-1.53,-1.39] |
PATIENTS' VARIABLES Female | 0.023 [0.00,0.05] | 0.031 [0.01,0.06] | 0.017 [-0.01,0.04] |
Age: | Â | Â | Â |
   0-19 | 0.340 [0.24,0.44] | 0.238 [0.12,0.36] | 0.207 [0.09,0.32] |
   20-39 | 0.291 [0.22,0.36] | 0.101 [0.02,0.18] | 0.127 [0.05,0.21] |
   40-59 | 0.237 [0.18,0.30] | 0.158 [0.09,0.22] | 0.164 [0.10,0.23] |
   60-79 (reference) |  |  |  |
   80+ | -0.135 [-0.21,-0.06] | -0.018 [-0.10,0.06] | -0.041 [-0.12,0.04] |
Age 0-19 in Vaud | 0.199 [0.12,0.28] | -0.004 [-0.10,0.09] | 0.086 [-0.00,0.18] |
Age 20-39 in Vaud | 0.026 [-0.05,0.10] | 0.055 [-0.02,0.14] | 0.051 [-0.03,0.13] |
Age 40-59 in Vaud | -0.058 [-0.12,0.01] | -0.051 [-0.12,0.02] | -0.046 [-0.11,0.02] |
Age 80+ in Vaud | 0.185 [0.10,0.27] | 0.194 [0.10,0.29] | 0.211 [0.12,0.30] |
Age 0-19 in Ticino | -0.437 [-0.58,-0.30] | -0.548 [-0.70,-0.40] | -0.484 [-0.63,-0.34] |
Age 20-39 in Ticino | -0.160 [-0.26,-0.06] | -0.176 [-0.28,-0.07] | -0.168 [-0.27,-0.07] |
Age 40-59 in Ticino | -0.208 [-0.29,-0.13] | -0.192 [-0.28,-0.11] | -0.189 [-0.27,-0.10] |
Age 80+ in Ticino | 0.095 [-0.01,0.20] | 0.075 [-0.03,0.18] | 0.098 [-0.01,0.20] |
Optional health insurance deductible | 0.065 [0.04,0.09] | 0.039 [0.01,0.07] | 0.043 [0.02,0.07] |
Out-of-pocket participation | 0.233 [0.18,0.28] | 0.146 [0.09,0.20] | 0.178 [0.12,0.23] |
Out-of-pocket participation at age 0-19 | 0.084 [-0.02,0.19] | 0.069 [-0.04,0.18] | 0.043 [-0.07,0.15] |
Out-of-pocket participation at age 20-39 | 0.205 [0.13,0.28] | 0.165 [0.08,0.25] | 0.139 [0.06,0.22] |
Out-of-pocket participation at age 40-59 | 0.052 [-0.01,0.11] | -0.020 [-0.09,0.05] | -0.025 [-0.09,0.04] |
Out-of-pocket participation at age 80+ | -0.161 [-0.24,-0.09] | -0.150 [-0.23,-0.07] | -0.136 [-0.22,-0.05] |
Out-of-pocket participation in Vaud | -0.062 [-0.12,-0.01] | -0.066 [-0.12,-0.01] | -0.067 [-0.12,-0.01] |
Out-of-pocket participation in Ticino | -0.107 [-0.18,-0.04] | -0.097 [-0.17,-0.02] | -0.116 [-0.19,-0.04] |
Treatment complexity: | Â | Â | Â |
   1-5 drugs | 0.112 [0.08,0.14] | 0.096 [0.06,0.13] | 0.082 [0.05,0.11] |
   6-10 drugs (reference) |  |  |  |
   11-15 drugs | -0.063 [-0.09,-0.03] | -0.055 [-0.09,-0.02] | -0.055 [-0.09,-0.02] |
   16-20 drugs | -0.089 [-0.13,-0.05] | -0.101 [-0.14,-0.06] | -0.102 [-0.14,-0.06] |
   21+ drugs | -0.186 [-0.23,-0.14] | -0.175 [-0.22,-0.13] | -0.174 [-0.22,-0.13] |
PHYSICIANS' VARIABLES Specialist prescriber | -0.245 [-0.27,-0.22] | -0.203 [-0.23,-0.17] | -0.194 [-0.22,-0.16] |
Hospital prescriber in Aargau | -0.871 [-0.93,-0.81] | -1.125 [-1.19,-1.06] | -1.101 [-1.17,-1.04] |
Hospital prescriber in Vaud | -0.344 [-0.40,-0.29] | -0.559 [-0.62,-0.50] | -0.571 [-0.63,-0.51] |
Hospital prescriber in Ticino | -0.737 [-0.84,-0.63] | -0.778 [-0.89,-0.67] | -0.756 [-0.86,-0.65] |
SUBSTITUTION GROUPS' VARIABLES Number of generics: | Â | Â | Â |
   1-2 (reference) |  |  |  |
   3-4 |  |  | 0.506 [0.46,0.55] |
   5-6 |  |  | 0.745 [0.70,0.79] |
   7+ |  |  | 0.522 [0.46,0.58] |
Number of treated patients: | Â | Â | Â |
   1-1000 (reference) |  |  |  |
   1001-2000 |  |  | 0.109 [0.07,0.15] |
   2001-3000 |  |  | 0.412 [0.35,0.47] |
   3001+ |  |  | 0.013 [-0.03,0.06] |
Price of brand medication: | Â | Â | Â |
   1st quintile |  |  | 0.181 [0.13,0.23] |
   2nd quintile |  |  | -0.006 [-0.07,0.05] |
   3rd quintile (reference) |  |  |  |
   4th quintile |  |  | 0.072 [0.03,0.12] |
   5th quintile |  |  | -0.064 [-0.12,-0.01] |
Relative price difference: | Â | Â | Â |
   1st quintile |  |  | -0.303 [-0.35,-0.25] |
   2nd quintile |  |  | -0.167 [-0.21,-0.12] |
   3rd quintile (reference) |  |  |  |
   4th quintile |  |  | 0.026 [-0.02,0.07] |
   5th quintile |  |  | 0.219 [0.16,0.28] |
Administration mode: Oral (reference) | Â | Â | Â |
   Topic |  |  | -0.644 [-0.71,-0.57] |
   Inhalation, nasal & ophthalmic |  |  | -1.329 [-2.05,-0.61] |
   Parenteral, rectal & vaginal |  |  | -0.676 [-0.76,-0.59] |
Original with special galenic form | Â | Â | -0.476 [-0.55,-0.41] |
At least one drug sold under license | Â | Â | -0.309 [-0.36,-0.26] |
Multiple package sizes | Â | Â | -0.233 [-0.27,-0.19] |
Constant | -0.554 [-0.60,-0.50] | 0.717 [0.64,0.80] | -0.289 [-0.38,-0.20] |
Substitution groups dummies | No | Yes | No |
3 char. ATC codes dummies | No | No | Yes |
Pseudo-R-squared | 0.089 | 0.229 | 0.194 |
AIC | 196,349 | 166,597 | 173,677 |
BIC | 196,671 | 169,867 | 174,542 |
Area under ROC curve | 0.699 | 0.811 | 0.791 |
Hosmer-Lemeshow chi2 | 4.295 | 101.676 | 139.595 |
Prob > chi2 | 0.830 | 0.000 | 0.000 |
Observations | 173,212 | 173,212 | 173,212 |