3 ms·

This study sounds like a waste of time. How you could ever follow up and prove that nuts have all those protective effects is beyond me -- as is why you would e

This study sounds like a waste of time. How you could ever follow up and prove that nuts have all those protective effects is beyond me -- as is why you would even think they do in the first place. However, we excluded participants with a history of cancer, heart disease, or stroke at baseline... Sounds like multiple regression, which is used to make insignificant statistics sound more plausible, by reducing the effect of a handful of confounding variables that the researchers happened to think of. That leaves behind any significant correlations plus the infinite number of confounding variables they didn't think of.

pyduan 13y ago
I wouldn't be so categorical. Regarding assessing causality, with an appropriate choice of instruments (food prices, tax on specific food categories) one could use instrumental variable regression to disambiguate the relationship. I'm not sure if this is standard practice in this field but a quick search seems to indicate this has been done before. As to why one would think nuts have protective effects at all -- I'm not a nutritionist, but from what I gather nuts do seem to have some desirable nutritional properties (high on unsaturated fats, protein and minerals), so that assertion doesn't seem that far-fetched to me.
- mtdewcmu 13y ago
  Observational studies like this could conceivably be useful under different circumstances. I think the chances of distinguishing meaningful from meaningless correlations would probably be higher if the variable being studied wasn't as ubiquitous as eating nuts and the causes of death weren't ordinary diseases of aging. For instance, an observational study could help determine the risk of disease from living in a specific area that was contaminated with a specific toxic substance. In order to make a very convincing case that the toxin had caused the diseases, you'd want to support it with stronger kinds of studies, that, say, demonstrated that that chemical was capable of causing the diseases that were observed. nuts do seem to have some desirable nutritional properties (high on unsaturated fats, protein and minerals) The problem is that none of those other components of food have been shown to prevent death, either, except in weak studies like this one. It's all very circular.

pyduan 13y ago

I wouldn't be so categorical. Regarding assessing causality, with an appropriate choice of instruments (food prices, tax on specific food categories) one could use instrumental variable regression to disambiguate the relationship. I'm not sure if this is standard practice in this field but a quick search seems to indicate this has been done before. As to why one would think nuts have protective effects at all -- I'm not a nutritionist, but from what I gather nuts do seem to have some desirable nutritional properties (high on unsaturated fats, protein and minerals), so that assertion doesn't seem that far-fetched to me.

mtdewcmu 13y ago
Observational studies like this could conceivably be useful under different circumstances. I think the chances of distinguishing meaningful from meaningless correlations would probably be higher if the variable being studied wasn't as ubiquitous as eating nuts and the causes of death weren't ordinary diseases of aging. For instance, an observational study could help determine the risk of disease from living in a specific area that was contaminated with a specific toxic substance. In order to make a very convincing case that the toxin had caused the diseases, you'd want to support it with stronger kinds of studies, that, say, demonstrated that that chemical was capable of causing the diseases that were observed. nuts do seem to have some desirable nutritional properties (high on unsaturated fats, protein and minerals) The problem is that none of those other components of food have been shown to prevent death, either, except in weak studies like this one. It's all very circular.