An older woman presents with fatigue, pain throughout her entire body, and the feeling that her brain is in a "fog." After taking a history and doing a thorough assessment, you conclude that this woman has fibromyalgia. What test would you do to confirm your diagnosis?
A. Erythrocyte sedimentation rate
B. Thyroid test
C. Cyclic citrullinated peptide test
D. There is no particular test that is diagnostic for fibromyalgia