As a follow on from my previous post about misleading food labels, this is also from the excellent NHS Behind the Headlines webpage. The bottom line is
“Don’t believe everything you read in the papers.”
My favourite example of where newspaper headlines can be misleading is the ongoing attempt by the Daily Mail to classify everything on the planet as either a cause or cure for cancer (take a look here).
Give the article a read (it is well worth it), but here are some of the highlights: Examples of spin in medical stories include:
- Reporting positive effects that were not statistically significant – so that the effects could have been the result of chance.
- Focusing on an outcome that the trial was not designed to study – for example, a trial that aimed, without success, to use acupuncture to treat hot flushes found incidentally that the treatment produced a slight improvement in sex drive. So the trial was spun with headlines such as “Acupuncture perks up sex drive”.
- Focusing on inappropriate sub-groups – for example, a trial of a new type 2 diabetes drug might be a total failure in the population at large but show a slight improvement in women in their twenties. This can be spun as an important breakthrough. However, type 2 diabetes is rare in women in their twenties, so the new drug would not actually be of great use.
- Ignoring safety data – we need to be sure that the potential benefits of treatment outweigh the risks but research summaries and press releases routinely omit mention of risks, side effects and so forth, and thus give an overly positive impression of results.
When you read a news report about a medical study, you may find it useful to consider:
- Was the research in humans? Headlines that talk of a “miracle cure” often relate to research conducted on, say, mice – and the results may not apply to people.
- How many people did the study involve? Small studies involving just a handful of people are more likely than large studies to reach conclusions that could simply be the result of chance.
- Did the study actually assess what’s in the headline? As mentioned, a headline saying acupuncture boosts your sex-life was actually based on a study into whether acupuncture could treat hot flushes.
- Who paid for the study? While most commercially funded studies are reliable, it is always worth checking if there could be any potential conflict of interest, for example where a company funds research into its own products.