Table 2– Spearman's rank correlation (ρ) to compare the relationship between 4-m gait speed and other health outcome measurements
ρp-value
Age-0.21<0.001
Height0.030.40
Weight0.010.86
BMI-0.090.03
FEV1 % predicted0.100.01
MRC dyspnoea score-0.55<0.001
ISW test0.78<0.001
ISW test % predicted0.72<0.001
SGRQ
 Symptoms-0.150.007
 Activity-0.51<0.001
 Impact-0.38<0.001
 Total-0.44<0.001
Charlson index-0.120.004
COTE index-0.090.03

  • BMI: body mass index; FEV1: forced expiratory volume in 1 s; MRC: Medical Research Council; ISW: incremental shuttle walk; SGRQ: St George’s Respiratory Questionnaire; COTE: chronic obstructive pulmonary disease-specific comorbidity test.