[eiieirurjdndjd]

If they had studied number of mosquito bites received and the probability of autism, would they have gotten the same result? Or if they studied outdoor air temperature during pregnancy and autism, would they have seen a link? Probably ... so be careful about assuming causality here.

[ams6110]

Mentioning mosquitos, we need to keep in mind that (if the conclusion of the study is true) we traded a small--and at the time not understood--increase in autism for a huge decrease in mosquito-related disease. Millions of people who would have died in childhood are alive thanks to DDT and other insecticides.

[gascan]

Yes, and at the time it might have been a good tradeoff- but today we can do better, at least outside the malaria belt.

[dmm]

Autism has also been linked to maternal age. Maybe older women just happen to also have more DDT because they had more time to accumulate it or they were alive longer for when DDT was widely used.

[Rovanion]

The study controlled for that:

> The odds of autism among offspring were significantly increased with maternal p,p'-DDE levels that were in the highest 75th percentile, with adjustment for maternal age, parity, and history of psychiatric disorders...

[kaitai]

They also could/should have adjusted for paternal age, which may be a significant factor (see [1] for lots of links). (There is some interesting statistical stuff going on with paternal age -- some researchers claim if you bin by birth year some of the paternal effect disappears, which is odd! However, the article under discussion considers only children born between 1987 and 2005, so it's not a huge range of birth years...) They do have data on paternal age, but they don't include it in Table 1. Odd.

[1] https://www.spectrumnews.org/news/link-parental-age-autism-e...

[eiieirurjdndjd]

Presumably they at least controlled for age race and socioeconomic level. If they didn’t then the results are very suspicious.

[skosuri]

"Adjusted for maternal age, parity, and maternal history of psychiatric disorders"

[dsfyu404ed]

I can already see the click-bait headlines:

"mosquito bites linked to autism"

"outdoor recreation during pregnancy may cause autism"

"are children conceived on camping trips more likely to be autistic?