Centre for Behavioural Research in Cancer, Cancer Council Victoria, 615 St Kilda Road, Melbourne, Victoria, 3004, Australia. Helen.Dixon@cancervic.org.au. Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, 3010, Australia. Helen.Dixon@cancervic.org.au. Centre for Behavioural Research in Cancer, Cancer Council Victoria, 615 St Kilda Road, Melbourne, Victoria, 3004, Australia. Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, Victoria, 3010, Australia.