How can anyone trust anything written today about science? In an earlier SHS post, I touched on how a pair of new studies–we were told by the Washington Post–demonstrated that routine prostate screening for cancer isn’t worth doing. The point of that post was not so much to focus on the findings but to criticize an American Cancer Society spokesperson for accusing those who get screened annually of pursuing a medicine of faith rather than evidence.
Imagine my jaw dropping, then, when I checked the Telegraph as I do every evening and the headline stated that the one of same studies cited in the Post story showed that routine prostate screening could save thousands of lives! From the story:
The European Randomised Study of Screening for Prostate Cancer (ERSPC), which looked at 182,000 men aged between 50 and 74, found that screening them for the disease could cut the number of deaths by 20 per cent.
If the trial’s results were replicated it would mean up to 2,000 lives could be saved in the UK every year. Any national programme could follow the pattern for that of breast cancer screening, which tests women between 50 and 70 and saves an estimated 1,400 lives a year.
Screening would involved men reaching middle age being asked to attend a local clinic every few years to have a blood test. This would check for high levels of a protein called Prostate Specific Antigen (PSA), which increases in people who have a tumour. If the results suggested prostate cancer, a biopsy would be taken and, if the cells appeared dangerous, the patient would undergo surgery or be monitored until intervention was appropriate.
My head is spinning. Back to the Post article:
The PSA blood test, which millions of men undergo each year, did not lower the death toll from the disease in the first decade of a U.S. government-funded study involving more than 76,000 men, researchers reported yesterday. The second study, released simultaneously, was a European trial involving more than 162,000 men that did find fewer deaths among those tested. But the reduction was relatively modest and the study showed that the tests resulted in a large number of men undergoing needless, often harmful treatment.
Together, the studies–released early by the New England Journal of Medicine to coincide with presentations at a scientific meeting in Stockholm–cast new doubt on the utility of one of the most widely used tests for one of the most common cancers.
How are these two diametrically opposed accounts of the same basic story to be reconciled? It looks like the difference arises from the choice of “experts” the respective journalists interviewed to interpret the findings. In the Telegraph, the emphasis was on the number of lives that could be saved with universal screening. In the Post, the experts emphasized the supposedly low utility of lives saved versus the costs in reduced quality of life for those being treated when the cancer is discovered.
Let’s consider this: The same data was used by two different newspaper reporters to promote two opposite conclusions for readers to reach from the stories. Or to put it in the vernaculr, each report spun the same story in a different directon.
Will Rodgers once famously said: “All I know is what I read in the newspapers, and that’s an alibi for my ignorance.” He didn’t know the half of it.