[1] Auckland Univ Technol, Ctr Interdisciplinary Trauma Res, Auckland 1142, New Zealand
[2] Auckland Univ Technol, Fac Hlth & Environm Sci, Auckland 1142, New Zealand
[3] Ko Awatea, Auckland, New Zealand
[4] Univ Otago, Dept Prevent & Social Med, Dunedin, New Zealand
[5] Auckland Univ Technol, Taupua Waiora Ctr Maori Hlth Res, Auckland 1142, New Zealand
[6] Johns Hopkins Univ, Sch Nursing, Baltimore, MD 21218 USA
[7] Oregon Hlth & Sci Univ, Dept Med Informat, Portland, OR 97201 USA
[8] Oregon Hlth & Sci Univ, Dept Clin Epidemiol, Portland, OR 97201 USA