Table 3.
Probit model and WTP in the rare disease scenario
| Exploratory variables | Model 1 (without covariates) a | Model 2 (reduced model) b | Model 3 (full model) c | |||
|---|---|---|---|---|---|---|
| Coefficient | 95% CI | Coefficient | 95% CI | Coefficient | 95% CI | |
| Bid | 8.45E−06*** | (7.64e−06, 9.25e−06) | 8.63E−06*** | (7.80e−06, 9.46e−06) | 8.66E−06*** | (7.82e−06, 9.50e−06) |
| Female | – | – | − 0.199* | (− 0.423, 0.026) | − 0.202* | (− 0.427, 0.024) |
| Working experience (senior) | – | – | − 0.178 | (− 0.418, 0.062) | − 0.201 | (− 0.454, 0.051) |
| Expertise in health insurance | – | – | − 0.189* | (− 0.420, 0.042) | − 0.219* | (− 0.460, 0.022) |
| Expertise in Pharmacy | – | – | 0.271 | (− 0.021, 0.563) | 0.252 | (− 0.062, 0.566) |
| Expertise in pharmacoeconomics | – | – | – | – | − 0.065 | (− 0.358, 0.227) |
| South | – | – | – | – | − 0.103 | (− 0.355, 0.149) |
| Western | – | – | – | – | 0.091 | (− 0.272, 0.453) |
| constant term | − 1.856*** | (− 2.044, − 1.668) | − 1.650*** | (− 1.927, − 1.373) | − 1.588*** | (− 2.195, − 0.980) |
| WTP | 219,691.1*** | (206,480.5, 232,901.7) | 191,155.8*** | (162,576, 219,735.6) | 183,391.5*** | (114,306.4, 252,476.6) |
aModel 1 includes response as the explained variable and Bid as the main exploratory variable; no other covariates are included in the model. bModel 2 is the reduced model, with the lowest AIC and four covariates. cModel 3 is the full model
*p < 0.1; **p < 0.05; ***p < 0.01