Table 5.

Comparison between the mean and P-value of disease activity measure according to the classification of acute-phase reagents

Variable	CDAI	DAS 28 CRP	DAS 28 ESR
Ferritin
Normal	21.3 ± 12.3	4.0 ± 1.0	4.8 ± 1.0
High	19.7 ± 11.2	4.0 ± 0.9	4.7 ± 1.4
P-value	0.800	0.538	0.881
ESR
Normal	21.8 ± 13.5	4.1 ± 1.0	–
High	19.8 ± 8.9	3.9 ± 0.8	–
P-value	0.364	0.116	–
CRP
Normal	21.2 ± 12.5	–	4.8 ± 1.1
High	21.5 ± 5.1	–	5.2 ± 0.4
P-value	0.932	–	0.190

CDAI = Clinical Disease Activity Index; CRP = C-reactive protein; DAS 28 = disease activity score (28 joints); ESR = erythrocyte sedimentation rate.