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The reporting emphasis here (unlike in the original paper) is on differences between survival rates in the UK and elsewhere, but there is an inherent likelihood of bias when survival rates are compared by observational data derived from general populations. In addition, the UK has been shown to be more competent than some other countries at coding and registering cancers at the time of diagnosis. (1)
It would make more sense to present survival rates alongside incidence and mortality rates, as the reader could then easily draw their own conclusions on whether comparisons such as those made in the headline are faulty. The original paper states that "truly valid comparisons require differences in registration practice, classification, and coding to be minimal."