Patients' and rheumatologists' preferences for the attributes of biological agents used in the treatment of rheumatic diseases in Spain.

Purpose: To define importance values assigned to attributes of biological agents (BAs) by Spanish patients with rheumatic diseases (rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis) and rheumatologists.

Patients And Methods: This was an observational, cross-sectional design based upon a rank-based full-profile conjoint analysis. A literature review and four focus groups were undertaken to identify attributes and levels.