EDITOR,--When Duncan Keeley states in his commentary to our paper that “feasibility studies … that fail to address these issues [workload, earlier diagnosis, and anxiety] should not be undertaken,”1 he ignores appropriate study design. Ours was a validation study: validity must be proved before money is spent on feasibility studies. Furthermore, such pragmatic outcomes are not appropriate in validation studies because the intensive assessment may well affect patient behaviour.

Keeley suggests that workload would “substantially increase.” However, opportunistic screening when patients attend for other reasons would …