Table 4.
Sensitivity analyses by treatment group
| Manipulation of variables | Incremental cost versus usual care per person (€) | Cost utility ratioa (€/QALY) | 
| Health system analysis: | ||
| Number of participants per pool session: | ||
| 30% lower (10 patients/group) | 773 | 5,900 | 
| 30% higher (20 patients/group) | 389 | 2,969 | 
| Salary of personnel: | ||
| 30% lower (monitor and nurse) | 479 | 3,656 | 
| 30% higher (monitor and nurse) | 554 | 4,229 | 
| No additional salary of nurse | 465 | 3,550 | 
| Best case scenario of salary, participation and effectivenessb | 348 | 1,200 | 
| Worst case scenario of salary, participation and effectivenessv | 830 | 75,455 | 
| Societal analysis: | ||
| Number of participants per pool session: | ||
| 30% lower (10 patients/group) | 1,288 | 9,832 | 
| 30% higher (20 patients/group) | 904 | 6,901 | 
| Salary of personnel: | ||
| 30% lower (monitor and nurse) | 994 | 7,588 | 
| 30% higher (monitor and nurse) | 1,069 | 8,160 | 
| No additional salary of nurse | 980 | 7,481 | 
| Distance to facilities per session: | ||
| Near (without bus ticket and 1.5 h spent) | 831 | 6,344 | 
| Far (4 bus ticket and 2.5 h spent) | 1,442 | 11,008 | 
| Best case scenario of salary, participation, effectiveness and nearb | 662 | 2,283 | 
| Worst case scenario of salary, participation, effectiveness and farc | 1,755 | 159,545 | 
QALY, quality adjusted life year.
aFrom the Spanish Health System, the cost-utility ratio threshold was set at € 23,153/QALY for 8 months in 2005; bpool rental + participation 20 persons per group + QALY differential at higher limit of 95% confidence interval; csalary 30% higher (monitor and nurse) + participation 10 persons per group + QALY differential at lower limit of 95% confidence interval.