Measuring treatment response in rheumatoid arthritis : the use of patient‐reported outcome measures

Rheumatoid arthritis (RA) is a chronic inflammatory joint disease that may have major consequences for a patient’s life. Treatment generally consists of pharmacological and non-pharmacological interventions, and focuses on relieving symptoms, reducing inflammation, controlling joint damage, and maintaining or improving functional ability and psychosocial functioning. To justify these interventions from health care and health economic perspectives, it is important to assess their effects using reliable, valid, and responsive outcome measures. This thesis consists of three main parts. The first part (Chapters 2 and 3) focuses on the psychometric properties of commonly used patient‐reported outcome measures. The second (Chapters 4 and 5) and third (Chapters 6 and 7) parts focus on the effects of non‐pharmacological treatment interventions, with an emphasis on the use of orthoses and assistive devices, respectively. In this final chapter, the main findings of the studies conducted within these themes are summarized.