[1] Univ Auckland, Facil Med & Hlth Sci, Auckland, New Zealand
[2] Univ Otago, Dept Med, Christchurch, New Zealand
[3] Kia Kaha Chemists, Christchurch, New Zealand
[4] Univ Christchurch, Te Whare Wananga Waitaha, Fac Hlth, Te Kaupeka Oranga, Christchurch 8041, New Zealand
[5] Univ Queensland, Sch Clin Med, Primary Care Clin Unit, Brisbane, Australia
[6] Univ Bath, Ctr Therapeut Innovat, Dept Life Sci, Bath, England
[7] Univ Otago, Dept Med, Burwood Campus,POB 4345, Christchurch, New Zealand