Table 1. Number of subjects with radiographic assessments on days 365 and 729.

	Abatacept n = 376 (%)	Placebo n = 160 (%)
Subjects included in analyses
Day 365	328 (87.2)	144 (90.0)
Baseline and day 365	328 (87.2)	144 (90.0)
Day 729	324 (86.2)	143 (89.4)
Baseline and day 729	315 (83.8)	139 (86.9)
Imputation on day 729*	9 (2.4)	4 (2.5)
Subjects not included in the analyses
No day 365 value†	2 (0.5)	1 (0.6)
No day 729 value‡	6 (1.6)	2 (1.3)

*Subjects are discontinued and qualified for imputation requirement. †Two subjects in the abatacept group had evaluative radiographic assessment outside the pre-specified visit window of day 365, and one subject in the placebo group had no radiographic assessment on day 365. ‡Subjects had evaluative radiographic assessment outside the pre-specified visit window of day 729.