We Analysed 1,000 Social Media Posts about 5 Popular Medical Tests

5 Controversial Tests: What Influencers Are Telling You About Medical Tests

When Kim Kardashian posted on Instagram about having had a full-body MRI, she enthused that the test can be “life saving”, detecting diseases in the earliest stages before symptoms arise.

What Kardashian neglected to say was there’s no evidence this expensive scan can bring benefits for healthy people, and it can carry harms including unnecessary diagnoses and inappropriate treatments.

We wanted to explore what influencers are telling us about medical tests.

5 Controversial Tests

While these tests can be valuable to some, all five carry the risk of overdiagnosis for generally healthy people. Overdiagnosis is the diagnosis of a condition which would have never caused symptoms or problems. Overdiagnosis leads to overtreatment, which can cause unnecessary side effects and stress for the person, and wasted resources for the health system.

As an example, estimates suggest 29,000 cancers a year are overdiagnosed in Australia alone.

These are the five tests we looked at:

The full-body MRI scan claims to test for up to 500 conditions, including cancer. Yet there is no proven benefit of the scan for healthy people, and a real risk of unnecessary treatment from “false alarm” diagnoses.

The “egg timer” test (technically known as the AMH, or anti-mullarian hormone test) is often falsely promoted as a fertility test for healthy women. While it may be beneficial for women within a fertility clinic setting, it cannot reliably predict the chance of a woman conceiving or menopause starting. However, low results can increase fear and lead to unnecessary and expensive fertility treatments.

Multi-cancer early detection blood tests are being heavily marketed as the “holy grail of cancer detection”, with claims they can screen for more than 50 cancers. In reality, clinical trials are still a long way from finished. There’s no good evidence yet that the benefits will outweigh the harms of unnecessary cancer diagnoses.

The gut microbiome test of your stool promises “wellness” via early detection of many conditions, from flatulence to depression, again without good evidence of benefit. There’s also concern that test results can lead to wasted resources.

Testosterone testing in healthy men is not supported by any high-quality evidence, with concerns direct-to-consumer advertising leads men to get tested and take testosterone replacement therapy unnecessarily. Use of testosterone replacement therapy carries its own risk of potential harms with the long-term safety in relation to heart disease and mortality still largely unknown.

What We Found

Together with an international group of health researchers, we analysed 982 posts pertaining to the above tests from across Instagram and TikTok. The posts we looked at came from influencers and account holders with at least 1,000 followers, some with a few million followers. In total, the creators of the posts we included had close to 200 million followers.

The vast majority of posts were misleading, failing to even mention the possibility of harm arising from taking one of these tests. We found:

• 87% of posts mentioned test benefits, while only 15% mentioned potential harms

• only 6% of posts mentioned the risk of overdiagnosis

• only 6% of posts discussed any scientific evidence, while 34% of posts used personal stories to promote the test

• 68% of influencers and account holders had financial interests in promoting the test (for example, a partnership, collaboration, sponsorship or selling for their own profit in some way).

Further analysis revealed medical doctors were slightly more balanced in their posts. They were more likely to mention the harms of the test, and less likely to have a strongly promotional tone.