Table 2.

Strength of association of laboratory values to the criterion standard, and ROC cutoff values that may be used to differentiate mildly active from moderately or severely active disease.

Laboratory VariablePearson CorrelationROC Area Under CurveROC Cutoffp
WBC0.460.7210.8 × 109 g/l< 0.01
Neutrophil0.410.797.5 × 109 g/l< 0.01
Hemoglobin−0.500.73119 g/l< 0.01
Platelet0.450.71353 × 109 g/l< 0.01
MCV−0.480.7381.0 fl< 0.01
Albumin−0.590.7940.0 g/l< 0.01
Ferritin0.530.6527.9 ng/ml< 0.01
AST−0.200.6424.0 U/l0.14
ALT−0.190.4632.0 U/l0.16
ESR0.620.6723.0 mm/h< 0.01
CRP0.610.735.5 mg/l< 0.01
D-dimer0.460.62367.0 ug/l< 0.01
  • ROC: receiver-operating characteristic curves; WBC: white blood cells; MCV: mean corpuscular volume; AST: aspartate aminotransferase; ALT: alanine aminotransferase; ESR: erythrocyte sedimentation rate; CRP: C-reactive protein.