Those with Alzheimer's likely won't last long as taxi drivers so they find a new profession. And voila their profession from the viewpoint of this study is no longer taxi driver.
Much surprise that our lauded peer review process didn't catch this.
> Additionally, death certificates included a field for reported usual occupation (the occupation in which the decedent spent most of their working life), generally completed by a funeral director with help from the decedent’s informant.
So, not as closed-case as you suggest.
Slam-dunking on studies is a top-tier trope on HN. All studies are flawed, but some are useful.
It is certainly harder to get published as an independent researcher, but it is also not unheard of. See discussion at: https://www.researchgate.net/post/Can_a_individual_without_a... Publishing your own study isn't the only way to critisise a hypothesis, you could also just write a rigouros blog post.
Also: Scientists are humans, not godlike beings in ivory towers, thus science lives from participation. If you can find a methological flaw in a study that you are confident about, consider writing them. Who knows, maybe they already accounted for it (and you learn something) or they didn't (and they learn something). Either way they get a chance to clarify or correct.
In the end the goal is to help figuring out what effective Alzheimers prevention looks like. Creating a good discourse around a study can be helpful, but it is also important to be rigorous and communicative when doing so. See as an example the discussion in the peer review of the discussed study, especially the section on survivorship bias: https://www.bmj.com/sites/default/files/attachments/bmj-arti...
If I wrote a study that has a flaw I'd like to be the first to hear about it, just like I like to get a bug report when my software has a bug. Especially if it is a good cause.
Firstly and perhaps most importantly, selection bias is possible because individuals who are at higher risk of developing Alzheimer’s disease may be less likely to enter or remain in memory intensive driving occupations such as taxi and ambulance driving. This could mean that the lower Alzheimer’s disease mortality observed in these occupations is not due to the protective effect of the job itself but rather because those prone to the disease may have self-selected out of such roles. However, Alzheimer’s disease symptoms typically develop after patients’ working years, with only 5-10% of cases occurring in people younger than 65 years (early onset).
Their explanation however only holds if pretty much all taxi drivers retire at 65 which is clearly not the case. It also ignores the relative prestige of professions. If your father both owned a store and drove a taxi for awhile which will you put on the death cert? Then do airline pilot plus owned a store.
Also dunking on studies is very much the point. The goal is to challenge beliefs and figure out where we are wrong.
> Here is there selection criterion and justification: “occupations involving extensive day-to-day navigation, with often unpredictable, real time navigational demands.”
> All subjects died between Jan 1 2020 (COVID) to Dec 31, 2022.
> There was no data on duration between active employment in listed employment categories and age of death.
This study is a formalization of existing outlier data, that many people associate with Alz resistance. This is basically anecdata.
It's likely that using ones brain on average more while driving may be a contributing factor. Wayfinding can be a neurally intense activity.
Without a doubt. Borderline useless.