1. Centre for Health, Activity and Rehabilitation Research (CHARR), School of Physiotherapy, Dunedin 9016, New Zealand
2. Department of Medicine, University of Otago—Wellington, Wellington 6242, New Zealand
3. Foundation for Equity & Research New Zealand, Wellington 6147, New Zealand
4. Department of Respiratory Medicine, Te Whatu Ora Capital, Coast and Hutt Valley, Wellington 6140, New Zealand