NYT changes, back-dates article after Wikipedia fact-checkers find error

JFarber sez,

On 3/27, someone submitted a question to the Wikipedia Reference Desks (where I volunteer) asking about what seemed like a silly claim in a NYT health article published that same day.

The article, which summarized a recent panel study on the health benefits of beverages, claimed that it was illegal to fortify soy milk with Vitamin D, and, because soy milk did not contain calcium, that the soy milk was not recommended as a substitute for cow's milk.

The NYT reported that claim as true, and used it to close their article.

Over the next 24 hours, the ref desk volunteers (including myself) followied the info back to its source, dicovered that the error was due to the original study's citation of a 1971 article on this point (which seems like pretty bad science, given how much nutritional laws have changed in that time)…and further tracked down plenty of evidence on both the public online documents of the Federal Register and on our own shelves which showed this claim to be absolutely false.

Wednesday night, I sent a letter to the NYT.

Sometime yesterday, the entire last section of the NYT article, which (according to the NYT website) was NYT's most emailed article for the last two days, was changed to the following sentence:

"Fortified soy milk is a good alternative for individuals who prefer not to consume cow milk," the panel said.

No letter or correction has been issued, however, calling attention to this error.

It seems safe to assume that most folks who were going to read the article have already done so, and will never know that the facts have been corrected.

Is it common journalistic practice to change old articles like that? Is it considered ethically appropriate for a major newspaper to just pretend that they were right all along, and give neither credit nor acknowledgement for their error? Seems a bit slimy to me, given the severity of the error, and the potential impact on everything from soy milk sales to public support for vegan parenting. You have to wonder if the process would have been the same for an error made regarding a less "countercultural" product.

Link to Wikipedia reference desk discussion and fact-finding, including a copy of the letter I wrote to the NYT,

Link to now-changed NYT article

I regret not having saved the original article text, but anyone who still has a copy of the paper from 2/27 will surely be able to see the difference in copy.

Update:
Charles sez, "I actually saved a copy of the article as a PDF and forwarded it to some friends before it was corrected. Here's the original text:"

Fortified soy milk is a good alternative for individuals who prefer not to consume cow milk," the panel said, but cautioned that soy milk cannot

be legally fortified with vitamin D and provides only 75 percent of the calcium the body obtains from cow's milk.