Science fact or science fiction? Making sense of cancer stories in the media

Cancer is a hot topic in the media, from headlines about the latest cancer-fighting ‘superfood’ to scare stories about the causes of cancer.

And hardly a week goes by without a front page dedicated to a potential “wonder drug” or new treatment.

And it’s no surprise – most of us have been touched by cancer in some way or other, so there’s a big appetite for news. But this wealth of information can be overwhelming – and can sometimes seem contradictory.

Is red wine good or bad for us? Just how much broccoli should we eat? And why does it take so long for headline-grabbing “breakthroughs” to result in better cancer treatments?

It can sometimes seem that scientists don’t know what they’re talking about, or that everything is over-hyped. How do you know what to believe?

For a start, at Cancer Research UK, we provide authoritative, evidence-based information about cancer, written by experts. Our award-winning patient information website, CancerHelp UK helps people find out more about cancer treatments and symptoms, as well as risks and causes. And this blog, as well as our news feed, aim to provide accurate and balanced coverage of the latest news stories and advances in cancer research.

The NHS Choices’ Behind the Headlines blog also covers cancer stories in the news in depth.

But how do you work out whether a cancer story in the media is a reasonable and accurate reflection of a new discovery, or has fallen victim to hype?

Let’s look in a bit more depth at how research works, and how to look behind the headlines.

How does science work?

Scientific research is a way of investigating the world that allows us to draw testable conclusions about how it works. It is an ongoing process, in which researchers test, reshape and retest their ideas in the light of new evidence.

To start with, researchers draw up an idea, or hypothesis, based on what’s already known, such as the results of previous experiments. Then the scientists carry out carefully designed studies, or experiments, to test their idea.

They collect and record detailed information and measurements, and analyse them to see if the results supports their idea or not.

It is also important that results are reproducible and reliable. Researchers will carry out the same experiment several times, to make sure the results are consistent and they didn’t make any mistakes.

And they will also use controls, which we’ll talk about later, to ensure that their results are genuine.

Sharing results

Scientists regularly publish their findings in academic journals, so other researchers around the world can see what they have discovered and test their conclusions.

The best journals have a strict process of peer review, meaning that new research is scrutinised by other experts before it is published (more on this below).

Building a body of knowledge

In this way, we build up a body of scientific evidence that supports an idea. It also means that ideas can change over time, as new evidence to support or overturn an idea comes to light. And advances in technology mean that we can look at old questions in a new way.

New research often supports and builds on an established idea, in which case the hypothesis becomes stronger. But sometimes, new results can appear to contradict a conventional idea.

Should we believe them, or ignore them?

How to decide if a story stands up

The key to understanding scientific stories in the media is looking at the evidence and deciding if it supports or contradicts what is already known, rather than just glancing at the headline.

But how do we know if this new evidence is reliable? It can be hard to tell, as some media reports don’t contain many details about the research. Here are some useful things to look for.

1) Look at the numbers

Science relies heavily on statistics, and the bigger the numbers, the more accurate they are likely to be.

Studies involving a handful of people aren’t going to be as reliable as those involving hundreds. And studies with thousands of participants will be more reliable still.

Let’s take the fictional example of a group of five people with cancer. Asking about their lifestyle, we find out that four of them go to the cinema once a week.

This could be interpreted to mean that going to the cinema is very strongly linked to developing cancer. That sounds rather high – and certainly enough to put you off a trip to see the latest blockbuster.

But a sensible researcher wouldn’t stop there. They’d go and look at a larger number of people, to see if this initial, tentative observation holds true. Suppose we then take a group of 5,000 people with cancer, and find that only 200 of them a regular movie-goers, rather than the 4,000 that we might predict from our smaller study.

This tells us that it’s likely the results of the first study were a statistical “blip” – the five people we initially chose weren’t representative of the general population – and going to the cinema has a much smaller impact on cancer risk. In this case, the larger study would be a more accurate reflection of the situation in real life.

But neither of these imaginary studies tell us for sure whether going to the cinema causes cancer.*

Why?

Because – crucially – we haven’t asked anything about the leisure habits of people who don’t get cancer. Perhaps they go to the movies even more. Maybe, in fact, a trip to the flicks can prevent cancer! So we need what’s known as a control group.

(*Just to be absolutely clear, going to the cinema does not cause cancer).

2) Look for controls

The idea of a control is fundamental to research, and ensures that the results of scientific experiments are meaningful.

In our fictional cinema study of 5,000 people with cancer, a good control group would be 5,000 people of similar ages who don’t have cancer. And it would help if we knew more about their lifestyles as well as their fondness for movies. For example, we need to know if they smoked, drank alcohol, were overweight or took lots of exercise, as all of these things can also affect the risk of cancer.

• There’s more about this kind of study on our Healthy Living pages, as well as a discussion of how to make sense of mixed messages about cancer risks.

Control groups are also absolutely critical in clinical trials of cancer treatments, to work out whether a new drug or treatment is more effective than the best current therapy. If seven out of ten people taking a new drug survive their cancer for five years, this is only meaningful if we know what happens to people who don’t take the drug.

• There’s more about clinical trials on our website.

In the lab, scientists use controls to check that their experiments are working properly and are free of contamination. For example, if they are testing whether a chemical dissolved in water can kill cancer cells, it’s important to also test the water alone.

3) Is it published? If so, where?

When looking at a cancer story in the media, it’s good idea to see if the research has been published in a scientific journal – this will often be mentioned in the report.

As we mentioned above, scientists share their results with the world by publishing them in scientific journals – periodical magazines filled with technical papers detailing the precise methods and data from their research.

When a researcher wants to publish a paper, they will send it to the editor of a journal. A number of experts in that research field will then scrutinise the data – this process is known as peer review. If the reviewers are happy that the results are reliable, then the paper will be published.

This doesn’t always happen. Often, the reviewers will suggest further experiments, or point out flaws in the data or methods. So the scientist will do more experiments, rewrite the paper and send it back to the same journal, or try a different publication. And if the research isn’t of a sufficiently high standard, it may not be published at all.

There are thousands of different journals produced around the world, but they are not all equal. Some have very stringent peer review processes, while others are less strict. And the top journals will only publish papers that are truly innovative and groundbreaking.

The importance of a journal can be roughly measured by its “impact factor” – how often other scientists refer to papers published in it. As a general rule of thumb, papers published in journals with a high impact factor are more likely to be significant steps forward in their field.

Another way that researchers share their results is by presenting them at scientific conferences through talks or poster presentations. Sometimes these stories are picked up by the media, especially in the summer – the main season for scientific meetings.

It’s important to remember that conference presentations aren’t subjected to the same rigorous peer review process that journals use. So it can be difficult to tell how reliable the research is, until it is published in a journal at a later date.

4) Who funded it?

Money for cancer research comes from a wide range of sources, including charities, the Government, the pharmaceutical industry and other companies. In some cases, this can influence the reporting of results.

Funding awarded by large, independent charities – such as Cancer Research UK or the Wellcome Trust – or Government bodies like the Medical Research Council is carefully reviewed by experts.

Our website has more information about how Cancer Research UK reviews its research funding, and we’ve previously written about our funding process on the blog.

Smaller trusts and charities may have different processes for awarding funding.

Research can also be funded by commercial organisations, which may have different standards of independent review. Their results may also be subject to confidentiality clauses due to commercial sensitivity.

It’s important to try and find out who funded a particular piece of research, especially if it seems to be promoting a specific treatment, food or other product. And this needs to be considered alongside other things, such as where the research was published, the size of the study and so on.

5) How advanced is the research?

In 2008, a national newspaper ran a headline stating “New hope of cure for all cancers“, and the story got widespread coverage across the media.

But what exactly was this amazing breakthrough?

Far from being a new drug for patients, the researchers had discovered the molecular structure of telomerase – an important cancer protein – in a species of tiny beetle. Although the discovery was important from a scientific point of view, there’s still a long way to go before this knowledge can be translated into new treatments for patients.

Every week we see science stories in the media based on results from cells grown in the lab, or animal models such as worms, fruit flies or mice. In many cases these results are interesting, but much more work needs to be done to prove a benefit for humans.

For example, back in 2007 another national paper ran a story with the headline “Cough syrup – the new cure for prostate cancer”. In fact, the researchers had tested a purified chemical found in low amounts in certain cough syrups in mice carrying prostate cancer cells. This certainly doesn’t mean that cough syrup itself is a cancer cure.

Headlines can often over-inflate the science presented in the rest of the story. So it’s important to read the whole story carefully, to check whether the research is still at an early, experimental stage, or whether it is actually being used to treat patients in clinical trials.

The weird, wacky and wonderful world of the Internet

The internet has led to an explosion of information about cancer. Much of it is accurate and reliable, but some of it is not. When reading stories about cancer on the internet, it’s wise to ask the same questions we’ve outlined here.

You may see stories about alternative therapies that claim to be a “100 per cent cure for cancer”, but there is usually no scientific evidence to support these promises. The general rule is that if something sounds too good to be true, it probably is.

There are several websites that offer authoritative scientific advice on complementary and alternative cancer treatments:

• Cancer Research UK’s CancerHelp UK site has information about research into such treatments, and detailed information about a number of specific therapies. There is also advice about how to tell if a website is likely to contain reliable information.
• The American Cancer Society (ACS) website also carries information about complementary and alternative treatments for people with cancer.
• Quackwatch has detailed information about various ineffective, hoax or potentially dangerous cancer “cures”.

So next time you read a cancer story in the news or on the web, make sure you look for the facts behind the headlines.

Kat

• Image of pool balls, piggy bank and library via Wikimedia Commons