Footnotes

• Funding: the authors acknowledge the financial support of the Stroke Association; Chest, Heart and Stroke Scotland; the National Health Service Research and Development Cardiovascular Disease Programme; and the World Cancer Research Fund. BG is funded by the Medical Research Council through Research Fellowship in Health of the Public. GDS holds a Robert Wood Johnson Foundation Investigators Award in Health Policy Research. PM is supported by a career scientist award funded by the Research and Development Office for Health and Personal Social Services in Northern Ireland. The Centre for Public Health Research (Massey University, Wellington, New Zealand) is supported by a Programme Grant from the Health Research Council of New Zealand. The authors’ work was independent of the funding sources.

• Competing interests: none declared.