About the Authors

Stewart J. Richmond

stewart.richmond@york.ac.uk

Affiliation Department of Health Sciences, University of York, Heslington, York, United Kingdom

Shalmini Gunadasa

Affiliation Health Services Research Unit, University of Aberdeen, Aberdeen, United Kingdom

Martin Bland

Affiliation Department of Health Sciences, University of York, Heslington, York, United Kingdom

Hugh MacPherson

Affiliation Department of Health Sciences, University of York, Heslington, York, United Kingdom

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: SJR. Performed the experiments: SJR. Analyzed the data: SG SJR MB HM. Wrote the paper: SJR SG HM MB.