Of course, the most common error committed by physicians and nurses (and the NYT) is the use of "at risk for [cancer]" when they mean "at risk of [cancer]."
Challenged on this point by other commenters, he added that
A person who says, "… at risk for …" show misunderstanding of the careful use of prepositions that distinguishes persons educated in English from those who merely grew up in an English-speaking country. Your ability to catch this error will enable you to avoid docs and nurses who are incompetent and probably not careful about washing their hands.
And in response to some additional negative feedback, he explained himself further:
I am a prescriptivist who believes that "you are judged by the words you use," and who has little use for prescribing descriptivism or for those who do not take care to understand the correct use of prepositions and soap.
It's possible that "Jimbino" is a sophisticated parody, perhaps created by another instance of the same research program that produced "John Cowan". [Sorry, John, that was a bad joke...] But whether he's crank or troll, meat or bot, "Jimbino" offers a classic picture of how individual quirks can be transformed into prescriptive "rules".
And as far as I can tell, his 'at risk for/of" issue is genuinely an individual quirk. If other peevers have fixated on "at risk of" vs. "at risk for", their concerns haven't been noted in the encyclopedic Merriam-Webster's Dictionary of English Usage, nor can I find any mentions of the question in other usage sites. (Perhaps some readers can spread a wider net?)
As a result, it's not clear how doctors and nurses (or New York Times writers) could become "educated in English" so as to learn this aspect of "the correct use of prepositions", other than by direct transmission of Jimbino's caprice. They certainly couldn't acquire this education by reading major journals like Science, PNAS, or PLoS One:
|"at risk for"||368||339||313|
|"at risk of"||310||168||326|
In fact, the statistics in the New York Times are somewhat more to Jimbino's taste: overall, since 1981, that publication shows 1,477 instances of "at risk for" vs. 3,725 of "at risk of", for a rate of 72% "at risk of".
What could be going on here? It's possible that Jimbino's prejudice is simply a random whim. But it's also possible that he's drawn a false conclusion from partial exposure to what seems to be a genuine difference in meaning (or at least in usage) between "at risk for" and "at risk of". (There's also "at risk from", but sufficient unto the day…)
The difference is subtle, and I'm not sure that I can define it correctly, One symptom can be seen in these statistics, comparing "extinction" and "AIDS" as things to be at risk for/or. (In the table below, the counts for Science and PNAS come from phrase search on the journals' own sites; the counts for Nature come from Google search, using the actual list of items found and returned rather than the estimate on the first page of results.)
|"at risk for extinction"||0||0||1||1|
|"at risk of extinction"||28||23||22||73|
|extinction: percent "of"||99%|
|"at risk for AIDS"||30||18||10||58|
|"at risk of AIDS"||0||0||1||1|
|AIDS: percent "of"||2%|
My (unreliable, post hoc) intuition about this difference is that extinction is a process that a group participates in, whereas AIDS is an external influence that individuals suffer from. In any case, in these three journals, "cancer" swings both ways:
|"at risk for cancer"||10||12||3||25|
|"at risk of cancer"||4||13||2||19|
|cancer: percent "of"||43%|
As for the New York Times, it behaves similarly, but the issue comes up rarely enough that we can see how hypersensitive Jimbino's peeving reflex must be on this point. Since 1981, "at risk for cancer" has appeared 8 times in the Times, while "at risk of cancer" has appeared 3 times.
So what happened to Jimbino? Assuming that he's not an initial foray by The Onion into the domain of Language Log comments, we might guess that he first became familiar with the "at risk of extinction" usage. Having over-generalized this pattern, he's left to choose between two hypotheses: either he mis-learned the English language, or everyone else did.
Then again, it may be a mistake to look for any rational or empirical basis for such peeves.
Wherever it came from, this particular peeve seems unlikely to have much memetic impact. But if Jimbino were John Dryden or William Strunk Jr., he might succeed in unsettling generations of clueless writers .
Update – it occurs to me that the choice between "at risk of" and "at risk for" might also (at least partly) reflect the influence of two different metaphors of motion.
In one case, the individual or group is sitting "in the way of" something bad bearing down on them: "in danger of (whatever)", "in peril of (whatever)". In the other case, the individual or group is in motion towards a bad end: "heading for (whatever)", "headed for (whatever)", "in line for (whatever)", "bound for (whatever)".
But as a contrary argument, observe that we also use "for" in many cases where the thematic individual is conceptually static: "ready for (whatever)", "braced for (whatever)".