1 The Farr Institute of Health Informatics Research, University College London, London NW1 2DA, UK. Electronic address: s.luchenski@ucl.ac.uk.
2 Institute for Social Policy, Housing and Equalities Research, Heriot-Watt University, Edinburgh, UK.
3 Pathway Charity, London, UK.
4 The Farr Institute of Health Informatics Research, University College London, London NW1 2DA, UK; Centre for Public Health Data Science, Institute of Health Informatics, University College London, London NW1 2DA, UK.
5 The Farr Institute of Health Informatics Research, University College London, London NW1 2DA, UK; Centre for Public Health Data Science, Institute of Health Informatics, University College London, London NW1 2DA, UK; Institute of Epidemiology and Health Care, University College London, London NW1 2DA, UK.