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Table 3 Summary of model performance for best OLS Tobit and TPM Item and domain models

From: Mapping the EQ-5D index from the cystic fibrosis questionnaire-revised using multiple modelling approaches

  Observed EQ-5D OLS models Tobit models TPM models
Domain (3) Item (5) Domain (3) Item (5) Domain (3) Item (8)
Mean 0.671 0.671 0.671 0.672 0.672 0.691 0.679
SD 0.282 0.223 0.245 0.225 0.250 0.236 0.254
Range of values - 0.349 - 1 - 0.099 - 1.04 - 0.165 - 1.183 - 0.053 - 0.985 - 0.167 - 1 - 0.221 - 0.985 - 0.200 - 1
ICC   0.715 0.801 0.716 0.811 0.717 0.820
RMSE - 0.127 0.111 0.173 0.136 0.127 0.096
MSE - 0.030 0.029 0.030 0.018 0.029 0.017
BIC - −214 383 45 626 256, − 201 574, 379
AIC - −254 −173 5 71 240, − 247 270, − 150
  1. OLS, ordinary least squares; TPM, two-part model; SD, standard deviation; Adj. R2, adjusted R2; RMSE, root of the mean square error; MSE, mean square error; AIC, Akaike information criterion; BIC, Bayesian information criterion.
  2. Model 3 = CFQ-R domains that are statistically significant at the 10% level + statistically significant squared terms; Model 5 = All CFQ-R items excluding the health domain items; TPM Model 8 = All CFQ-R items excluding the health domain items + age and gender.