Popular prostate cancer videos on YouTube 'inaccurate and biased'

'An analysis of YouTube videos on prostate cancer has found biased and misleading medical information which could harm patients' Sky News reports

'An analysis of YouTube videos on prostate cancer has found biased and misleading medical information which could harm patients' Sky News reports

"'Be wary' about prostate cancer YouTube videos, scientists warn," reports Sky News.

Researchers viewed the 150 first-listed videos on YouTube for prostate cancer screening and treatment, checking them against standard patient information quality criteria. They found that 77% had errors or bias either in the videos or the comments beneath them. Worryingly, the most popular videos were the ones that scored worst on the quality checks.

Videos were also more likely to explain benefits than harms of screening and treatments.

There are more than 600,000 videos on YouTube about prostate cancer, each with thousands of views. That means that potentially millions of people are getting healthcare information on this common form of cancer from unvalidated videos, which may be posted by people with commercial interests, or with misguided views about unproven treatments.

Online access to information and support about cancer can be valuable, but only if it is accurate and unbiased. Before accepting advice given online, it's a good idea to think about who is providing the information, whether they are qualified to give accurate advice, and whether they have reasons to provide biased or incomplete information, such as having a commercial or financial motive.

Also, look out for the Information Standard quality mark, which certifies that the information is accurate, evidence-based and up-to-date. Read more about the Information Standard.

You can read reliable Information Standard-certified information on prostate cancer treatment on the NHS website.

Be aware that there's currently no screening programme for prostate cancer in the UK, because it has not been proved that the benefits would outweigh the risks.

Where did the story come from?

The researchers who carried out the study were mostly from New York University in the US, with others from Monash University in Australia, the Royal College of Surgeons in Ireland, the Department of Urology and LSU Health Foundation in the US and the Prostate Cancer Centre in Poland.

The study was funded by the Prostate Cancer Foundation and the Edward Blank and Sharon Cosloy-Blank Family Foundation. It was published in the peer-reviewed journal European Urology on an open-access basis, so it is free to read online.

The study was reported accurately by Sky News.

The Mail Online report repeatedly said that 77% of the videos contained inaccurate information. However, this figure took into account comments posted underneath the video, which are not necessarily the responsibility of the original content provider.

What kind of research was this?

This was a review of a sample of 150 of the more than 600,000 videos about prostate cancer on YouTube, reviewed against pre-set quality criteria. While the study gives an indication of the quality of the videos, it can't tell us about all the videos on offer.

What did the research involve?

Researchers looked at the first videos that appeared on YouTube after searching for "prostate cancer screening" (first 75 of 173,000 videos) and "prostate cancer treatment" (first 75 of 444,000 videos).

They checked the videos using the Discern questionnaire. This is a validated questionnaire to assess the quality of healthcare information provided to the public. Videos were scored from 1 to 5, where 1 is poor quality and 5 high quality.

The Discern questionnaire has 16 questions. It says that a good quality information source will:

  • have explicit aims
  • achieve its aims
  • be relevant to consumers
  • make sources of information explicit
  • make date of information explicit
  • be balanced and unbiased
  • list additional sources of information
  • refer to areas of uncertainty
  • describe how treatment works
  • describe the benefits of treatment
  • describe the risks of treatment
  • describe what would happen without treatment
  • describe the effects of treatment choices on overall quality of life
  • make it clear there may be more than 1 possible treatment choice
  • provide support for shared decision-making

The researchers also looked at the popularity of a video, based on the number of views per month and the proportion of users who gave the video a thumbs-up rating. They then calculated the relationship between quality and popularity.

What were the basic results?

According to the Discern questionnaire, 63% of the videos had a score of less than 3 out of 5, suggesting moderate to poor quality, and 20% scored poorly for misinformation. In total, 77% contained some inaccurate or biased information either in the video or in comments beneath the video.

While most of the videos (75%) scored well for describing the benefits of treatment, only 53% scored well for describing the harms of treatment.

Only 50% of the videos scored well for supporting the process of shared decision making, by which patients and their doctors make decisions together, based on unbiased information about which treatments to choose.

Some videos showed a commercial bias (27%), favoured expensive new treatments without evidence that they were superior to standard treatments (25%), or suggested complementary or alternative treatments (19%).

The study found that the most popular videos were those from commercial companies and from patients. But these sorts of videos were on average a lower quality than videos from healthcare providers and professional or government groups.

How did the researchers interpret the results?

The researchers said their research showed "many popular videos about prostate cancer on YouTube lack key elements of shared decision making and contain biased content."

They add that the "significant inverse relationship" between information quality and popularity of videos is "highly concerning".


Prostate cancer is the most common cancer in men, and decisions about screening and treatment are complex.

While some YouTube videos may be helpful and informative, the lack of quality control means that some are biased or inaccurate. This study showed that three quarters may contain some misleading or biased information, either in the video itself or the comments posted underneath. The lack of good quality information about the risks of screening and treatment is important, as many prostate cancer treatments have significant potential harms as well as benefits.

The main limitation of the study is that it was able to review only 150 of the thousands of videos about prostate cancer online. While the Discern checklist used is a validated quality measure, it cannot be used to check the truth of every claim made in the videos (for example about personal stories of patients). It acts only as a measure of the likely quality of the information, based on what is and is not included in the video.

Looking for information about health and medicine online is now part of everyday life. It's more important than ever to ensure the sources you trust are reliable, evidence-based and free from bias, especially when making important decisions about cancer screening and treatment.

And when looking at health information online, especially if it is hosted abroad, you should be aware that the reason a specific treatment or service is being promoted may be down to commercial, rather than strictly evidence-based, reasons.

See our information about prostate cancer.

Article Metadata Date Published: Wed, 28 Nov 2018
Author: Zana Technologies GmbH
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