Which imaging or laboratory test is commonly used in the diagnosis of rheumatoid arthritis?

The rheumatoid factor test is commonly utilized in the diagnosis of rheumatoid arthritis because it detects the presence of rheumatoid factor antibodies in the blood, which are often elevated in individuals suffering from this autoimmune condition. This test serves as an important diagnostic tool, as rheumatoid arthritis typically presents with these specific antibodies.

While x-rays of affected joints can help assess joint damage and progression of the disease over time, they are not specifically used for initial diagnosis. A complete blood count (CBC) can provide valuable information regarding overall health and detect anemia or inflammation but does not specifically indicate rheumatoid arthritis. Joint aspiration, which involves withdrawing fluid from a joint for analysis, may help in diagnosing conditions causing joint swelling but is not routinely used to diagnose rheumatoid arthritis specifically. The rheumatoid factor test provides distinct evidence that aligns with the autoimmune nature of rheumatoid arthritis, making it a key component of the diagnostic process.