Observational Trial With Enbrel

EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single index value. The VAS component rates current health state on a scale from 0 millimeter (mm) (worst imaginable health state) to 100 mm (best imaginable health state); higher scores indicate a better health state.

EQ-5D: participant rated questionnaire to assess health-related quality of life in terms of a single utility score. Health state profile component assesses level of current health for 5 domains: mobility, self-care, usual activities, pain or discomfort, and anxiety or depression; 1 indicates better health state (no problems); 3 indicates worst health state (confined to bed). Scoring formula developed by EuroQol group assigns a utility value for each domain in the profile. EQ-5D score is transformed to EQ-5D-TTO score ranging from -0.205 to 0.999; higher score indicates a better health state.

WPAI:SHP is 6-question participant rated questionnaire to determine the amount of absenteeism, presenteeism, work productivity loss and daily activity impairment attributable to rheumatoid arthritis for a period of 7 days prior to each visit. It yields 4 sub-scores: work time missed (absenteeism), impairment while working (presenteeism or reduced on-the-job effectiveness), overall work impairment (work productivity loss or absenteeism plus presenteeism) and activity impairment (daily activity impairment). These sub-scores are transformed to impairment percentages (range from 0 to 100), with higher numbers indicating greater impairment and less productivity.

Participants' utilization of healthcare resources was evaluated as number of events for healthcare resources utilization including: number of visits to general practitioners, visits to rheumatologist, visits to other medical specialists, inpatient hospitalizations, inpatient rehabilitations, inpatient follow-up treatment, outpatient rehabilitations, physiotherapy, and other healthcare utilizations. At baseline, number of events for participants' healthcare resources utilization during last 12 months before enrollment into the study were documented. After enrollment, number of events for participants' healthcare resources utilization were documented for last 6 months after previous documentation.

Participants' duration of healthcare resources utilization was evaluated as number of days for healthcare resources utilization including: duration of visits to general practitioners, to rheumatologist, to other medical specialists, inpatient hospitalizations, inpatient rehabilitations, inpatient follow-up treatment, outpatient rehabilitations, physiotherapy, and other healthcare utilizations. At baseline, number of days for participants' healthcare resources utilizations during last 12 months before enrollment into the study were documented. After enrollment, number of days for participants' healthcare resources utilization were documented for last 6 months after previous documentation.

Duration of working disability was assessed as number of days a participant was disable to work. Duration of work disability was considered as "0" if participant was not disable to work during period of assessment. At baseline, participants' duration of working disability during last 12 months before enrollment into the study was documented. After enrollment, participants' duration of working disability was documented for last 6 months after previous documentation.

DAS28 calculated from the number of swollen joints (SJC) and tender joints (TJC) using the 28 joints count, the erythrocyte sedimentation rate (ESR) (millimeters per hour [mm/hour]) and Patient global assessment of disease activity (recorded on a VAS of 0 mm [very good] to 100 mm [very bad]). Total score range: 0 to 10, higher score indicated more disease activity. DAS28 less than (<) 2.6 = remission, DAS28 less than or equal to (<=) 3.2 = low disease activity, DAS28 greater than or equal to (>=) 3.2 to <=5.1 = moderate disease activity, DAS28 greater than (>) 5.1 = high disease activity.

Number of swollen joints was determined by examination of 28 joints and identifying when swelling was present. The number of swollen joints was recorded on the joint assessment form at each visit, no swelling = 0, swelling =1.

Number of tender joints was determined by examining 28 joints and identified the joints that were painful under pressure or to passive motion. The number of tender joints was recorded on the joint assessment form at each visit, no tenderness = 0, tenderness = 1.

ESR is a laboratory test that provides a non-specific measure of inflammation. The test assesses the rate at which red blood cells fall in a test tube. Normal range is 0-30 mm/hour. A higher rate is consistent with inflammation.

DAS28 calculated from the number of swollen joints (SJC) and tender joints (TJC) using the 28 joints count, the erythrocyte sedimentation rate (ESR) (millimeters per hour [mm/hour]) and Patient global assessment of disease activity (recorded on a VAS of 0 mm [very good] to 100 mm [very bad]). Total score range: 0 to 10, higher score indicated more disease activity. DAS28 defined remission was classified as a score of <2.6.

The DAS28-based European League Against Rheumatism (EULAR) response criteria was used to measure individual response as none, good, and moderate, depending on the extent of change from baseline and level of disease activity reached (final values). Good responders: change from baseline >1.2 with DAS28 final value <=3.2; moderate responders: change from baseline >1.2 with DAS28 final values >3.2 to <=5.1 and >5.1 or change from baseline >0.6 to <=1.2 with DAS28 final values <=3.2 and >3.2 to <=5.1; non-responders: change from baseline <=0.6 with DAS28 final values <=3.2, >3.2 to <=5.1 and >5.1 or change from baseline >0.6 to <=1.2 with DAS28 final values >5.1. Good and moderate responders were considered to have DAS28 response.

Duration of morning stiffness was defined as the time elapsed when participant woke up in the morning and was able to resume normal activities without stiffness in minutes (If none was present = 0; If stiffness persisted the entire day, 999 minutes was recorded [largest value possible to document] which may also include values up to 1440 minutes [= complete day]).

Participants assessed arthritis pain using a 0 mm - 100 mm Visual Analog Scale (VAS) where 0 mm = minimum possible pain (best) and 100 mm = maximum possible pain (worst).

Physician global assessment of disease activity was measured on a 0 mm to 100 mm Visual Analog Scale (VAS), with 0 mm = no disease activity and 100mm = maximum possible disease activity.

Patient global assessment of disease activity was measured using a 100 mm Visual Analog Scale (VAS) ranging from 0 mm= very good to 100 mm = very bad.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement.

Participants assessed their fatigue during the last 7 days using a 0 mm - 100 mm VAS, where 0 mm = no fatigue and 100 mm = worst possible fatigue.