Category Archives: Plain language summaries

A collection of scientific abstracts translated to “plain English”

Plain language summary: calcium supplements and heart attacks

The research:

Calcium supplements with or without vitamin D and risk of cardiovascular events: reanalysis of the Women’s Health Initiative limited access dataset and meta-analysis

The summary:

This trial took information from 36,282 women who had been through the menopause, and looked at them to see whether taking calcium supplements made them more likely to have a heart attack.  Half of the women were given calcium and vitamin D supplements, while half were given a placebo (sugar-pill).  The trial found that taking calcium and vitamin D increased the risk of heart problems slightly, including heart attacks.  Some women took their own personal calcium supplements as well as those provided by the study, and these women had no increased risk of heart attack.

Re-analysis of some older trials found that calcium and vitamin D increased the risk of heart attacks and strokes.  The way that calcium supplements are used should be examined, to see if change is needed.

The caveats:

This paper appears to find that women who take the highest amount of calcium (their own tablets plus the ones provided by the study) have no increase in risk compared to women who don’t take any calcium at all.  If this was a true effect, we would expect women who take the most calcium to have the highest risk. Other authors have published papers that find no evidence of risk with calium and vitamin D supplements.

This paper is discussed in more detail in this blog post.

Plain language summary: Trastuzumab emtansine for breast cancer

The research:

Trastuzumab Emtansine for HER2-Positive Advanced Breast Cancer.

The summary:

This trial looked at a drug called T-DM1, which is designed to treat a type of breast cancer called HER-2 positive breast cancer. T-DM1 was compared to a combination of two drugs that are already available.  It found that cancer progression was delayed by about three months in women who received T-DM1, from 6.5 months to 9.5 months.  These women also lived roughly six months longer than the other group. Serious side effects were common in both groups, however they were less common in women receiving T-DM1.

The caveats:

The women recruited for this trial were reasonably healthy when they started.  Women were only allowed to enrol if:

  • they had breast cancer that had failed to respond to treatment with trastuzumab (which is one of the components of T-DM1) plus another drug
  • their breast cancer had spread (either locally or more widely).
  • they were still able to perform light work, such as housework or an office job.

In real-world conditions, women who receive treatment with T-DM1 might not be this fit, so might not get the same benefits as the women in the trial.

The problem with abstracts

I’ve written at reasonable length here and here about why I think plain language summaries on scientific abstracts would be a good idea. I plan to start producing a few myself (and if anyone would like to volunteer to chip in, I’d be more than grateful!). Before I start though, I thought a brief post on why we should treat abstracts with a little caution might be a good idea.

Abstracts are pretty ubiquitous in the scientific literature. They’re designed to give a brief overview of the paper; summarising the methods and the main results so that the reader can tell if the article is relevant to their needs without reading the whole thing. If the abstract looks promising, then that’s a good sign that it’s worth investing the time to read the whole thing.

But there are some caveats. Some of the same temptations that journalists face crop up – it’s very alluring to state your findings in the grandest terms, to get people interested in reading the whole paper. In fact, it’s not as uncommon as you might think to find that abstracts are actually misleading. A recent paper (and I do realise the irony of linking to an abstract here!) found that nearly a quarter of randomised controlled trials in the field of rheumatology have misleading claims in their abstracts. Another recent paper (and you can read the whole thing this time) found that when abstracts are misleading, or contain “spin”, this in turn leads to spin in the media reports of it.

I suspect (or rather, hope) that all of this is usually done with relatively pure intentions, but there’s no getting away from it – misleading information is not useful, and potentially harmful.

The other important thing to consider is that abstracts are short – they simply do not contain all of the detail of the full paper, as that would rather defeat the object. But this means that they miss out some information that can sometimes be crucial. For instance, the abstract may state that a trial is randomised, while the text reveals that randomisation was done using a method that’s not robust. A small detail like this might cast doubt over the findings of the entire trial, but you won’t find it in the abstract. That’s why it’s alway important to fully “critically appraise” a paper (in other words, take it apart and check for holes) before taking its conclusions at face value.

So as I embark on my little experiment, I’ll be bearing all of this in mind; and you should too. I will do my best to honestly represent the studies I cover, and I’ll read the full thing before producing my summaries whenever possible. However, there’s only one of me, and like most people in the modern world I have rather limited time available to do this in. Be patient with me, and take everything with a pinch of salt.

Update: The first plain language summary, trastuzumab emtansine for breast cancer, is now online.  All future summaries will be published under the Plain language summaries category.  As ever, all feedback gratefully received!

Plain language summaries – an update

Thank you for all of the responses to my post last Friday, describing my colleague’s idea for plain language summaries to be included in journal abstracts.  The reaction was pretty positive, with some welcome constructive criticism too. 

That post was written very much on the spur of the moment (during my lunch break just after the idea was suggested, to be precise!), so after a little time to calm down and cogitate I’ve decided to run something of a pilot scheme, or a proof of concept.  I’ve created a new blog category over to the right there called “Plain language summaries”, and I’ll be adding as many abstracts there as I have time to get through (disclaimer: that might not be many). I’ll kick things off with a general discussion of the strengths and limitations of abstracts (including how they can be misleading in their own right), and then hopefully there will be a steady trickle of content. 

So once again watch this space, and if anyone has any ideas or comments on the feasibility of what I’m trying to do here (or wants to help!), do get in touch.  I know I already have one recruit in the form of the lovely Hayley (from A Healthy Dose of Skepticism), but this is definitely a case of the more the merrier!