RT Journal Article SR Electronic T1 Functional disorders and chronic pain JF Clinical Medicine JO Clin Med FD Royal College of Physicians SP e242 OP e243 DO 10.7861/clinmed.Let.21.2.4 VO 21 IS 2 A1 Richard Sawyer YR 2021 UL http://www.rcpjournals.org/content/21/2/e242.2.abstract