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, 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.