Table 5.
Total knee replacement: differences in costs and outcomes between APEX randomised groups
| Difference (intervention – control) | |||
|---|---|---|---|
| N | Mean | (95 % CI) | |
| OUTCOMES | |||
| QALYs | |||
| QALY gain – available cases a | 201 | 0.010 | (−0.039 to 0.060) |
| QALY gain – imputed data b | 316 | 0.009 | (−0.040 to 0.057) |
| Primary clinical outcome | |||
| WOMAC pain score improvement – available cases c | 273 | 3.83 | (−0.83 to 8.49) |
| WOMAC pain score improvement – imputed data d | 316 | 3.33 | (−1.21 to 7.88) |
| COST | |||
| Initial inpatient stay | |||
| Total of inpatient stay – available cases a | 268 | £89 | (£–194 to £371) |
| Total of inpatient stay – imputed data b | 316 | £152 | (£–140 to £444) |
| Secondary care after initial discharge | |||
| Inpatient admissions – available cases a | 213 | -£170 | (£–365 to £24) |
| Inpatient admissions – imputed data b | 316 | -£239 | (£–489 to £11) |
| Outpatient visits – available cases a | 265 | £2 | (£–47 to £52) |
| Outpatient visits with – imputed data b | 316 | £13 | (£–43 to £70) |
| Total secondary care cost – available cases a | 203 | -£165 | (£–391 to £61) |
| Total secondary care cost – imputed data b | 316 | -£226 | (£–485 to £34) |
| Community-based resources | |||
| Total community based costs – available cases a | 170 | -£56 | (£–142 to £31) |
| Total community based costs – imputed data b | 316 | £0 | (£–99 to £99) |
| Total NHS cost – complete NHS cost cases a | 148 | -£343 | (£–822 to £137) |
| Total NHS cost – imputed data b | 316 | -£74 | (£–490 to £343) |
| Personal social services (PSS) | |||
| Total personal social services – available cases a | 259 | -£4 | (£–95 to £87) |
| Total personal social services – imputed data b | 316 | -£4 | (£–89 to £82) |
| Total NHS + PSS cost – complete NHS+PSS cost cases a | 145 | -£404 | (£–924 to £117) |
| Total NHS + PSS cost – imputed data b | 316 | -£77 | (£–528 to £374) |
a Adjusted for minimisation variables (baseline WOMAC c pain score and surgical approach) and baseline utility for QALYs, robust standard errors
b Adjusted for minimisation variables (and baseline utility for QALYs), robust standard errors, M=20 multiple imputation sets, bootstrapped confidence intervals with 1000 replications
c Adjusted for minimisation variables (baseline WOMAC pain score and surgical approach) and baseline utility for QALYs
d Adjusted for minimisation variables, M=20 multiple imputation sets from main statistical analysis