Design an Intervention Study.

Randomized controlled trials are commonly designed to compare the effectiveness of treatments in rheumatoid arthritis (RA). In a clinical trial (intervention study), researchers apply interventions or preventive services to patients and examine outcomes. Clinical trial design consists of the following categories: choice of intervention and control, selection of patients, informed consent, baseline measurement, bank specimens, randomized allocation and blinding, and outcome measurements. Here, we discuss the design of clinical trials for RA.