<s>[INST] What are the most common types of arthritis? [/INST] The most common form of arthritis in the United States is osteoarthritis. Other common types of arthritis include rheumatoid arthritis, gout, and fibromyalgia. Fibromyalgia is included in arthritis for public health purposes. Source: CDCP GOV. Link: https://www.cdc.gov/arthritis/basics/faqs.htm. Field: Rheumatology. Disease: Arthritis </s>