US active-synovitis negative (PD+GS)	US active-synovitis positive (PD+GS)	p
	(n=55)	(n=45)
ADA serum trough levels (mean ± SD) (n=35)	6.9±4	7.2±4	0.836
ADA suboptimal serum trough levels (<1.274 μg/ml) (n=5)	3	2	0.619
ADA optimal serum trough levels (>1.274 μg/ml) (n=30)	17	13	0.419
ETN serum trough levels (mean ± SD) (n=50)	1.8±1	1.8±1	0.994
ETN suboptimal serum trough levels (<1.242 μg/ml) (n=18)	10	8	1.00
ETN optimal serum trough levels (>1.242 μg/ml) (n=32)	17	15	0.552
IFX serum trough levels (mean ± SD) (n=15)	4.1±4	3±2	0.570
IFX suboptimal serum trough levels (<1.5 μg/ml) (n=5)	3	2	1.00
IFX optimal serum trough levels (>1.5 μg/ml) (n=10)	5	5	0.573