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Comment by tedchs | Hacker News Reader

IMHO, anything to do with Body Mass Index (BMI) is fake science. Ironically, this writeup is also from nih.gov: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2930234/

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BMI is often inadequate to evaluate an individual, but it has proven effective for measuring across larger sample size, since its coarseness will swing both ways and more or less cancel out.

Spot on. And let's be honest even at the individual level - you know whether your BMI is "high" because you are a muscular jock or just an average joe that (over)eats the wrong things and is a couch potato (same probably applies to the ultra-lean runner types on the low side).

How do you measure effectiveness ? I am under the impression we have very few (any?) large scale intervention that have an objective positive effect, I'd be glad to know more.

Clarification unrelated to the BMI comment, but the writeup isn't from nih.gov. The article is found through PubMed, a search engine and data repository. Your article was published in the 'British Journal of General Practice'. OP's article is from 'Cureus'. PubMed just has copies of the articles.

Saying its ironic that nih.gov has both articles is somewhat like saying its ironic that Google has any two articles.

Disclaimer directly from the linked webpages: "As a library, NLM provides access to scientific literature. Inclusion in an NLM database does not imply endorsement of, or agreement with, the contents by NLM or the National Institutes of Health. Learn more about our disclaimer."

While for individual cases clinicians shouldn't rely on BMI much, and only use it for screening, in studies it makes sense to use it because it's a useful tool. A person with a BMI of 30 is almost always fatter than a person with a BMI of 20. The outliers (like athletes with big bones) wouldn't change the statistical analysis.

It's in the same boat with IQ, it's a useful tool if you accept it has limited uses.

Except it's completely not (neither are.)

BMI can't distinguish between fat and muscle which is enough to disqualify it from any serious consideration.

IQ is similarly simplistic and attempts to measure something for which we don't even have an agreed-upon definition.

BMI is literally just correcting weight for height. That's it. What other methods should researchers use?

For one thing, it does a terrible job for tall people.

https://www.fatcalc.com/bf lists several alternatives, along with their estimated accuracies. BMI is the least accurate method short of taking a wild guess.

Came here to say this. Bullshit study.

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