Table 2 Clinical and laboratory characteristics of the rheumatoid arthritis and primary knee osteoarthritis patients

Disease duration (years)

0.005*

 Range

2–17

1.5–15

 (Mean ± SD)

(6.94 ±2.98)

(4.69 ± 3.21)

Morning stiffness duration (min)

< 0.001*

 Median (IQR)

45 (20–60)

15 (10–25)

VAS

0.64

 Range

0–9.5

0–8.5

 (Mean ± SD)

(3.85±2.78)

(4.09 ± 2.35)

ESR mm/1^st h

< 0.001*

 Range

10–90

8–17

 Median (IQR)

20 (13–32.25)

12 (10–15)

CRP mg/dl

< 0.001*

 Range

2–33

2–5

 Median (IQR)

12 (5.5–15)

4(2–5)

RF (positive)

41/50

5/50

< 0.001*

RF titer IU/ml

 Range

8–220

–

 Mean ± SD

48 (28–73.3)

Positive Anti-CCP titer U/ml

31/50

0/50

Anti-CCP Abs titer U/ml

5–70

–

29.5 (17.5–39.5)