The media in the UK and many other countries have been full this week of stories about mobile phones and brain cancer. Some were really pretty scary - the Daily Express gave a SHOCK WARNING: MOBILE PHONES CAN GIVE YOU CANCER. But others were much more cautious. The BBC reported that a link between phones and cancer was "not clearly established" and that "the evidence was too weak to draw strong conclusions from." What's going on?
In our article on ESP and the significance of significance, I made a prediction on the controversy surrounding psychologist Daryl Bem's paper "Feeling the Future" - the one that claimed to find evidence for some forms of ESP (extra-sensory perception). "This one will run and run", I boldly prophesied. And so it came to pass.
The media today are full of reports that women who drink lots of coffee might reduce their risk of developing one type of breast cancer. For instance, the BBC reported on it here, and the Daily Mail here. But is the evidence really there?
The UK news media have reported quite extensively a newly published paper by Wald, Simmonds and Morris on screening for cardiovascular disease (CVD) - that is, disease of the heart and blood vessels (principally heart attacks and strokes). The paper concluded that screening should be based on the patient's age alone, and not on other risk factors for CVD. But I'm not going to examine the conclusion - I'm interested in the way the authors dealt with uncertainty.
The New York Times has published an excellent (well, I thought so) article called Do Cellphones Cause Brain Cancer?. What's particularly good about it is the clear but thorough way that it explains the problems of looking for causes of rare diseases, and describes the methods used for dealing with uncertainty in this challenging context.
Statistical significance testing is one of the commonest formal ways of handling some kinds of uncertainty, but arguably it's one of the most misunderstood. We've posted a new article about statistical significance, in the context of some very controversial psychological experiments about extra-sensory perception (ESP).
The recent study on alcohol and cancer published in the British Medical Journal is a fine piece of epidemiology and attracted a lot of coverage of the estimate that 10% of male cancers and 3% of female cancers could be attributed to alcohol. But while it is useful as a description of what happens in populations, as usual when translated to an individual it stops looking so impressive.
Yesterday’s announcement that the Fukushima accident was now upgraded to a Level 7 was greeted with some consternation, since this is not only the same level as Chernobyl but as high as the scale can go – there is no Level 8. But is this scale really fit for its purpose?
Statistical significance testing is a pretty tricky concept. We're planning to post an article on it soon, but until we get round to it, here's a link to something excellent on the topic from the xkcd Web comic. They're illustrating exactly what people misunderstand. Maybe we needn't bother with the article after all...
