[1] AUT Univ, Sch Rehabil & Occupat Studies, Auckland, New Zealand
[2] Univ Auckland, Sch Populat Hlth, Auckland 1, New Zealand
[3] Univ Otago Christchurch, Princess Margaret Hosp, Dept Med, Christchurch, New Zealand
[4] Univ Auckland, Freemasons Dept Geriatr Med, Auckland 1, New Zealand