The Glucosamine/chondroitin Arthritis Intervention Trial (GAIT) was a large, randomized, placebo-controlled trial conducted at several sites across the United States. The GAIT team, funded by NCCAM and the National Institute of Arthritis and Musculoskeletal and Skin Diseases, actually conducted two studies:

• a primary, or original, study that investigated whether glucosamine and/or chondroitin could treat the pain of knee osteoarthritis.
• an ancillary, or additional, study that investigated whether the dietary supplements could diminish the structural damage of knee osteoarthritis.