1. Institute of Applied Health Research, University of Birmingham, United Kingdom (S.J., S.K.).
2. Oxford University Hospitals NHS Foundation Trust and University of Oxford, United Kingdom (G.A.F.).
3. Nuffield Department of Primary Care Health Sciences, University of Oxford, United Kingdom (F.D.R.H., R.J.M., J.P.S.).
4. Primary Care Research Centre, University of Southampton, Southampton, United Kingdom (M.L.).
5. Primary Care Unit, Department of Public Health & Primary Care, University of Cambridge, United Kingdom (J.M.).
6. Centre for Academic Primary Care, Population Health Sciences, University of Bristol, United Kingdom (R.P.).