Cancer survival figures are misleading

2 Survival is a perfectly valid measure for comparisons within randomised control trials but is misleading for comparisons across time and place. 3 The apparent increases in survival since 1971 are, unfortunately, unlikely to be the result of improvements in cancer treatment alone as the article seems to claim.(29 April.) 2 Wegwarth O, Schwartz LM, Woloshin S, Gaissmaier W, Gigerenzer G. Do physicians understand cancer screening statistics? A national survey of primary care physicians in the United States.