^aCentre for Research into Cancer Prevention and Screening, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland

^bDivision of Gastroenterology, University of California San Francisco, San Francisco, California, USA

^cFlinders Centre for Innovation in Cancer, Flinders University, Bedford Park (Adelaide), South Australia

^dBowel Cancer Screening Hub – South of England, Royal Surrey County Hospital NHS Foundation Trust and University of Surrey, Guildford, Surrey, UK

Correspondence to Callum G. Fraser, PhD, Centre for Research into Cancer Prevention and Screening, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland Tel: +44 1382 553799; fax: +44 1382 425679; e-mail: callum.fraser@nhs.net

Received December 25, 2013

Accepted January 29, 2014