The DAS28 was calculated using the tender and swollen joint counts, c-reactive Protein (CRP), or erythrocyte sedimentation rate (ESR), and the Patient's Global Assessment of Disease Activity (PtGADA). The joint assessment was carried out on 28 joints.

For the analysis, DAS28 values were categorized into the following groups:

• DAS28 < 2.6: clinical remission
• DAS28 from 2.6 to ≤ 3.2: low disease activity
• DAS28 from > 3.2 to 5.1: moderate disease activity
• DAS28 > 5.1: high disease activity

Full Analysis Set (FAS) using Non-Responder Imputation (NRI). FAS is defined as all patients with a DAS28 ≥ 2.6 at baseline who took at least 1 dose of Certolizumab Pegol and had at least 1 valid post-Baseline DAS28 value.

Patients rated how much pain they were experiencing at the time of the visit caused by their Arthritis using a Visual Analog Scale (VAS) ranging from 0 (no pain) to 100 (most severe pain). A negative value in Change from Baseline indicates an improvement from Baseline to Visit 9 (around Week 104).

Full Analysis Set (FAS) using Mixed Model with Repeated Measures imputation (MMRM). FAS is defined as all patients with a DAS28 ≥ 2.6 at baseline who took at least 1 dose of Certolizumab Pegol and had at least 1 valid post-Baseline DAS28 value.

The HAQ-DI contains 20 items on a 4-point scale ranging from 0 (without any difficulty) to 3 (unable to do). The 20 items are grouped in 8 categories with 2 to 3 items each. The category scores are averaged into an overall HAQ-DI from 0 to 3. Scores of 0 to 1 generally represent mild to moderate difficulty, 1 to 2 represent moderate to severe disability, and 2 to 3 indicate severe to very severe disability. A negative value in Change from Baseline indicates an improvement from Baseline to Visit 9 (around Week 104).

Full Analysis Set (FAS) using Mixed Model with Repeated Measures imputation (MMRM). FAS is defined as all patients with a DAS28 ≥ 2.6 at baseline who took at least 1 dose of Certolizumab Pegol and had at least 1 valid post-Baseline DAS28 value.

The CDAI was calculated with the equation:

CDAI= Tender Joint Count + Swollen Joint Count + PtGADA/10 + PhGADA/10 where PtGADA (mm) is the Patient's Global Assessment of Disease Activity using a Visual Analog Scale (VAS) ranging from 0 to 100, and PhGADA (mm) is the Physician's Global Assessment of Disease Activity using a VAS ranging from 0 to 100. Thus, the CDAI ranges from 0 to 76, with higher values indicating higher disease activity. If any individual term was missing, then the CDAI was set to missing. A negative value in Change from Baseline indicates an improvement from Baseline to Visit 9 (around Week 104).

Full Analysis Set (FAS) using Mixed Model with Repeated Measures imputation (MMRM). FAS is defined as all patients with a DAS28 ≥ 2.6 at baseline who took at least 1 dose of Certolizumab Pegol and had at least 1 valid post-Baseline DAS28 value.