1. Centre for Public Health Research, Massey University, Wellington, New Zealand
2. School of Fundamental Sciences – Statistics, College of Sciences, Massey University, Palmerston North, New Zealand
3. Statistical Consulting Unit, The Australian National University, Acton Australian Capital Territory, Canberra, Australia
4. Faculty of Engineering and Information Sciences, University of Wollongong, New South Wales, Australia
5. Health Services Research Centre, Victoria University of Wellington, Wellington, New Zealand
6. Section of Epidemiology and Biostatistics, School of Population Health, Faculty of Medical and Health Sciences, The University of Auckland, Auckland, New Zealand