Table 2.

Mean utility value (health state value) for people with secondary progressive multiple sclerosis stratified by postal ambulation scale score

Postal ambulation scale score (descriptor)	No of patients	Mean (SD) utility	Change in utility
1 (Unrestricted)	2	1.00
2 (Up to 500 m unaided)	1	0.620	0.380
3 (Up to 250 m with aid)	9	0.643 (0.087)	−0.023
4 (Walk indoors with assistance)	20	0.389 (0.343)	0.254
5 (Wheelchair dependent)	46	0.015 (0.31)	0.374
6 (Restricted to bed)	6	−0.260 (0.24)	0.275

Delaying progression from postal ambulation scale 4 to 5 by 9 months gained 0.281 (0.374×0.75) QALYs; 0.031 (0.374×0.083) QALYs are gained by preventing a one month hospital treated relapse and 0.021 (0.254×0.083) QALYs for each untreated or community treated relapse prevented.