Rheumatoid arthritis is an autoimmune disease in which the joint lining becomes inflamed as part of the body's immune system activity, leading to chronic pain and loss of function. Gout is a painful condition attacking the small joints, such as the big toe, and can usually be controlled by medication and changes in diet. Lupus is a chronic rheumatic disease which causes inflammation that may affect many parts of the body, including the heart, lungs, skin, joints, kidneys, and nervous system. Fibromyalgia is an arthritis-related condition characterized by generalized muscular pain and fatigue. The most prevalent form of arthritis, osteoarthritis, is often simply referred to as arthritis and is a degenerative joint disease in which the cartilage covering the ends of bones in the joints degenerates, causing pain and loss of movement.

The Field Representative's Manual for 2002 forward defined the term "arthritis," as "an inflammation of one or more joints of the body, usually producing pain, redness, and stiffness." This definition was not routinely shared with respondents.

Possible responses included:

• Arthritis (ARTHRITEV)

• Rheumatoid arthritis (ARTHRHEUMEV)

• Gout (ARTHGOUTEV)

• Lupus (ARTHLUPUSEV)

• Fibromyalgia (ARTHFIBROEV)

• Other joint condition (ARTHOTHEV)

The variable ARTHRITEV (Ever told arthritis) is also available for sample children in 1997 forward, as well as all sample adults in 2001.