Sitas, F., Yap, S., Egger, S., Christian, K., Hodgkinson, V., Barton, M., Banks, E., Canfell, K., O'Connell, D. L., Nair-Shalliker, V.. Elsevier; 2015. The Cancer, Lifestyle and Evaluation of Risk Study (CLEAR): rationale and design of an unmatched "case-spouse control" study of over 10,000 participants in New South Wales, Australia.