Assessment of Clinical Effectiveness and Safety of Adalimumab and High Dose Methotrexate in Routine Clinical Practice

The Clinical Disease Activity Index (CDAI) is a composite index for assessing rheumatoid arthritis disease activity. Twenty-eight tender joint counts, 28 swollen joint counts, the participant's global assessment of disease activity (on a visual analog scale [VAS] from 0 to 10 cm), and a physician's global assessment of disease activity (measured on a VAS from 0 to 10 cm) are summed to yield the total score. The total CDAI score ranges from 0 to 78 with higher scores indicating higher disease activity. Remission is defined as a CDAI score ≤ 2.8.

The SDAI is a validated measure of rheumatoid arthritis disease activity. Twenty-eight tender joint counts, 28 swollen joint counts, global disease activity assessed by the participant on a visual analogue scale from 0 to 10 (cm), global disease activity assessed by an investigator on a visual analogue scale from 0 to 10 (cm), and serum levels of C-reactive protein (CRP; mg/dL) were included in the SDAI score. Scores on the SDAI range from 0 to 86. An SDAI score ≥26.1 indicates high disease activity, an SDAI score between 11.1 and 26.0 indicates moderate disease activity, an SDAI score between 3.4 and 11.0 indicates low disease activity, and an SDAI score ≤3.3 indicates clinical remission.

The Health Assessment Questionnaire - Disability Index (HAQ-DI) is a self-reported assessment specific for rheumatoid arthritis. It consists of 20 questions referring to eight domains: dressing/grooming, arising, eating, walking, hygiene, reach, grip, and daily activities. Participants assessed their ability to do each task over the past week using the following response categories: without any difficulty (0); with some difficulty (1); with much difficulty (2); and unable to do (3). Scores on each task were summed and averaged to provide an overall score ranging from 0 to 3, where zero represents no disability and three very severe, high-dependency disability. HAQ remission indicating normal physical function is defined as HAQ-DI < 0.5.

The European Quality of Life-5 Dimensions Health Questionnaire (EQ-5D) is a participant-answered questionnaire scoring 5 dimensions: mobility, self-care, usual activities, pain/discomfort and anxiety/depression. For each dimension the participant is asked for a three-level assessment of their health on the current day: "no problems" (1), "some problems" (2), "extreme problems" (3). EQ-5D health states, defined by the EQ-5D descriptive system, are converted into a single summary index by applying a formula that essentially attaches values (also called QOL weights or QOL utilities) to each of the levels in each dimension. EQ-5D Summary Index values range from -0.11 (worst health state) to 1.00 (perfect health state). Positive numbers indicate improvement from baseline.

The van der Heijde modified Total Sharp Score (mTSS) is a measure of the level of joint damage. X-rays of hands and feet were taken at the visit. Joints were scored for erosions on a scale of 0 (no damage) to 5 (complete collapse) and joint space narrowing on a scale of 0 (no damage) to 4 (ankylosis or complete dislocation). Erosion scores and narrowing scores were added to obtain the mTSS (range = 0 [normal] to 398 [maximal disease]). An increase in mTSS from Baseline represents disease progression and/or joint worsening, no change represents halting of disease progression, and a decrease represents improvement.