Table 2.
Comparison of results from three methods of regression analysis of costs per patient
| |
GLM on complete cases n = 592[[1]]a |
GLM on MI dataset n = 717[[2]]b |
Heckman on complete cases n = 717, 125 obs censored[[3]]c |
||||
|---|---|---|---|---|---|---|---|
| Variables | Exp (Coeff) | S.E. | Exp (Coeff) | S.E. | Exp (Coeff) | S.E. | |
| Episode Characteristics |
Age in 2003 |
0.996 |
0.003 |
0.997 |
0.002 |
1.000 |
0.012 |
| Gender |
0.982 |
0.063 |
1.009 |
0.060 |
1.085 |
0.281 |
|
| Lives alone |
1.052 |
0.059 |
1.047 |
0.056 |
1.106 |
0.275 |
|
| Barthel score at admission |
0.973 |
0.009** |
0.984 |
0.008* |
0.884 |
0.061* |
|
| EQ5D score at admission |
0.973 |
0.090 |
0.935 |
0.087 |
1.400 |
0.435 |
|
| Descriptors of IC Service |
Acute Admission Avoidance Service |
0.930 |
0.129 |
0.812 |
0.092* |
6.723 |
0.960* |
| Type of IC |
3.181 |
0.079** |
3.150 |
0.070** |
5.146 |
1.274 |
|
| Transferred before end of IC episode |
1.144 |
0.310 |
1.259 |
0.258 |
1.316 |
1.422 |
|
| Completed IC episode |
2.094 |
0.300* |
2.396 |
0.248** |
4.611 |
1.318 |
|
| Other IC Outcome |
2.703 |
0.337** |
2.796 |
0.287** |
4.374 |
1.475 |
|
| Patient Died (Reference. Group) |
|
|
|
|
|
|
|
| Descriptorsof IC-related Services |
Referral – Primary |
0.777 |
0.123* |
0.764 |
0.121* |
0.936 |
0.576 |
| Referral – Hospital |
0.914 |
0.158 |
0.777 |
0.134 |
4.523 |
0.930 |
|
| Referral – Other |
1.001 |
0.212 |
0.935 |
0.195 |
2.240 |
0.984 |
|
| Referral – Social Workers (Reference Group) |
|
|
|
|
|
|
|
| Alternative to IC – Other |
1.053 |
0.079 |
1.058 |
0.077 |
0.508 |
0.451 |
|
| Alternative to IC – Home |
1.121 |
0.074 |
1.058 |
0.070 |
1.112 |
0.329 |
|
| Alternative to IC – Hospital (Reference Group) |
|
|
|
|
|
|
|
| Interactions | Barthel score at admission*Type of IC |
1.031 |
0.018 |
1.017 |
0.097 |
1.131 |
0.092 |
| Acute Admission Avoidance Service* Type of IC |
1.214 |
0.163 |
1.217 |
0.136 |
0.579 |
0.752 |
|
| Transfer before IC end*Type of IC |
1.145 |
0.185 |
1.176 |
0.169 |
1.145 |
0.825 |
|
| Completed Episode*Type of IC |
1.152 |
0.195 |
1.112 |
0.162 |
0.240 |
0.952 |
|
| Other IC Outcome*Type of IC |
0.717 |
0.708 |
0.583 |
0.534 |
0.773 |
2.846 |
|
| Patient died*Type of IC (Reference group) |
|
|
|
|
|
|
|
| _constant |
1140.3 |
0.421** |
951.5 |
0.360** |
345.3 |
1.866** |
|
| N |
|
592 |
717 |
|
|
717 |
|
| Censored obs |
|
|
|
|
|
125 |
|
| R-Squared |
|
0.359 |
|
|
|
0.634 |
|
| Rho | 0.950 | ||||||
* 5% level of significance, ** 1% level of significance; Dependent variable: cost per patient for GLM and log of cost per patient for Heckman Selection model;
IC = Intermediate care; aMethod 1 assumes that missing data are MCAR;
bMethod 2 assumes that missing data are MAR; cMethod 3 assumes that missing data are MNAR.