Table 2

Summary of utility values and VFQ-25 scores
N Mean (SD) Median (IQR) Observed range Possible range*
EQ-5D 131 0.8 (0.2) 0.8 (0.7 - 1.0) −0.1 - 1.0 −0.6 – 1.0
SF-6D 126 0.7 (0.1) 0.7 (0.6 - 0.9) 0.4 - 0.9 0.3 – 1.0
TTO 123 0.9 (0.2) 1.0 (0.8 - 1.0) 0.2 - 1.0 0 – 1.0
VFQ-25 132 72.9 (22.1) 81.1 (57.8 - 91.6) 17.1 - 99.4 0 – 100

* Higher values indicate better health.

EQ-5D = UVs derived using EuroQoL Index tool. UK population norms (n = 1763) by age group are the following, mean (SD) 45–54: 0.85 (0.25); 55–64: 0.80 (0.26); 65–74: 0.78 (0.26); 75+: 0.73 (0.27) [52].

SF-6D = UVs derived from SF-36 using SF-6D algorithm [53].

TTO = time trade-off utility value.

VFQ-25 = 25-item national eye institute visual function questionnaire.

Bozzani et al.

Bozzani et al. BMC Ophthalmology 2012 12:43   doi:10.1186/1471-2415-12-43

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