Table 3 Spearman’s rank correlation coefficients of EQ-5 domains, EQ-VAS, EQ-5D index and derived disability weights

Mobility

1

Self-care

0.3916*

1

Usual activities,

0.5849*

0.4725*

1

Pain/discomfort

0.4721*

0.3898*

0.4550*

1

Anxiety/depression

0.3364*

0.3429*

0.2253

0.3151*

1

EQ-VAS

− 0.6308*

− 0.4928*

− 0.6051*

− 0.4300*

− 0.4162*

1

EQ-5D index

− 0.7553*

− 0.7494*

− 0.7160*

− 0.6270*

− 0.5922*

0.7288*

1

EQ-VAS disability weight

0.6308*

0.4928*

0.6051*

0.4300*

0.4162*

− 1

− 0.7288*

1

EQ-5D disability weight

0.7553*

0.7494*

0.7160*

0.6270*

0.5922*

− 0.7288*

− 1

0.7288*

1

.90 to 1.00

Nearly, practically, or almost: perfect, distinct, infinite

.70 to .90

Very large, very high, huge

.50 to .70

Large, high, major

.30 to .50

Moderate, medium

.10 to .30

Small, low, minor

.00 to .10

Trivial, very small, insubstantial, tiny, practically zero