The "CAP questionnaire," developed by modifying the CAP-Knee questionnaire to assess potential nociplastic pain features in painful musculoskeletal disorders, has been described. The "CAP questionnaire" is used in people with musculoskeletal pain and diagnostic subgroups of osteoarthritis, back pain, and fibromyalgia. There is no Turkish version of the CAP questionnaire. This study aims to investigate the cultural adaptation, validity, and reliability of the Turkish version of the "CAP questionnaire."