[1] Western Norway Univ Appl Sci, Dept Hlth & Functioning, Bergen, Norway
[2] Haraldsplass Deaconal Hosp HDS, Dept Rehabil Serv, Bergen, Norway
[3] Vestfold Hosp Trust, Norwegian Natl Advisory Unit Ageing & Hlth, Tonsberg, Norway
[4] Newcastle Univ, Fac Med Sci, Newcastle Upon Tyne, England