Brain-Imaging Studies Hampered by Small Data Sets, Study Finds

For two decades, researchers have used brain-imaging technology to try to identify how the structure and function of a person's brain connects to a range of mental-health ailments, from anxiety and depression to suicidal tendencies. But a new paper, published Wednesday in Nature, calls into question whether much of this research is actually yielding valid findings. The New York Times reports: Many such studies, the paper's authors found, tend to include fewer than two dozen participants, far shy of the number needed to generate reliable results. "You need thousands of individuals," said Scott Marek, a psychiatric researcher at the Washington University School of Medicine in St. Louis and an author of the paper. He described the finding as a "gut punch" for the typical studies that use imaging to try to better understand mental health.

Studies that use magnetic-resonance imaging technology commonly temper their conclusions with a cautionary statement noting the small sample size. But enlisting participants can be time-consuming and expensive, ranging from $600 to $2,000 an hour, said Dr. Nico Dosenbach, a neurologist at Washington University School of Medicine and another author on the paper. The median number of subjects in mental-health-related studies that use brain imaging is around 23, he added. But the Nature paper demonstrates that the data drawn from just two dozen subjects is generally insufficient to be reliable and can in fact yield 'massively inflated' findings," Dr. Dosenbach said. The findings from the Nature paper can "absolutely" be applied to other fields beyond mental health, said Marek. "My hunch this is much more about population science than it is about any one of those fields," he said.

That's a Funny Headline . . .

[Kunedog]

. . . but a penis-imaging study would have been funnier.

Re:

[ceoyoyo]

There's one where they got people to have sex in an MRI scanner. The images are interesting.

Re:

[splutty]

Only a small brain could come up with that!

Saw an email the other day for a $90 cat scan

[Powercntrl]

I opened the email because I live in the USA and that's an incredible bargain. Turned out it was for reading the chips that get implanted in cats.

maybe the data set is not small enough?

[3seas]

https://www.scoopwhoop.com/cul... [scoopwhoop.com]

There is a clue in there somewhere.

Re:

[narcc]

It seems amazing at first. A guy loses half of his brain with seemingly no loss of function. Then you read his story and realize he probably wasn't using that bit in the first place.

Looking for the mind in the brain

[UpnAtom]

It hasn't really yielded results so far.

Same as genetic studies

[clawsoon]

Virtually every headline you've seen (thankfully less frequent now) about a "gene for this" or a "gene for that" suffered from the same problem. Except in the case of a few genetic diseases, you basically shouldn't believe a genetic study unless it has at least 30,000 participants. Even better if it has 300,000. And even then the data can mislead you, as in Polygenic adaptation on height is overestimated due to uncorrected stratification in genome-wide association studies [elifesciences.org], which points out problems in st

This is an actual problem

[WillAffleckUW]

In Medical Genetics, we have a lot of difficulties.

One, the quantities are limited. People are using their brains, so you have to wait 15 years (for people with MCI or AD) before they donate them before you have tissue. And for controls, the joke is they live forever (we have 104 year old subjects who joined in the 1970s, for example, still using their brains).

Two, most studies that are published are very small - usually t size (15-40 subjects with matched controls). It takes a lot of work to get those up