A Study of MabThera (Rituximab) in Patients With Rheumatoid Arthritis and an Inadequate Response to Methotrexate

Percentage Change in Disease Activity Score 28 (DAS28) From Baseline to Week 24

The DAS28 score is a measure of the participant's disease activity calculated using the tender joint count (TJC) \[28 joints\], swollen joint count (SJC) \[28 joints\], participant's global assessment of disease activity \[visual analog scale: \[VAS\] 0 equals (=) no disease activity to 100=maximum disease activity\] and the erythrocyte sedimentation rate (ESR) for a total possible score of 0 to 10. Scores less than (\<) 2.6 indicate best disease control and scores greater than or equal to (≥) 5.1 indicate worse disease control. DAS28 Remission is defined as a DAS28 score \< 2.6. The average improvement at each visit to the group score is equal to the formula (Previous DAS28 minus \[-\] current DAS 28)/ Previous DAS 28 x 100. Negative percentages indicate that the participant has worsened in comparison to last evaluation, and positive percentages indicate improvement of its DAS28 score and correlated with a bettering of clinical situation.

Time frame: Baseline and Week 24

Percentage of Participants Whose DAS28 Improved by >1.2 at Week 24

The DAS28 score is a measure of the participant's disease activity calculated using the TJC \[28 joints\], SJC \[28 joints\], participant's global assessment of disease activity \[VAS: 0 = no disease activity to 100 = maximum disease activity\] and the ESR for a total possible score of 0 to 10. Scores \< 2.6 indicate best disease control and scores ≥ 5.1 indicate worse disease control. DAS28 Remission is defined as a DAS28 score \< 2.6. An improvement of \>1.2 was considered to be clinically significant improvement.

Time frame: Baseline and Week 24

Change in Bone Density (in Participants Untreated With Bisphosphonates)

Bone mineral density test was performed using x-ray radiation and the values of bone density were provided directly by the apparatus as grams per square centimeter (g/cm\^2) . T-score is the number of standard deviations above or below the mean for a healthy 30 year old adult of the same sex and ethnicity as the participant. A T-score with above -1 is normal bone density level. A T-score between -1 and -2.5 means that the bone density is below normal and it might be a sign of an osteopenia and may also lead into osteoporosis. A T-score below -2.5 indicates osteoporosis.