Editors on the reference desk discovered an error in the New York Times last week, leading to a correction of the offending article and also prompting the paper to explain how it handles the publication of corrections.

The mistake appeared in the paper's 27 March Personal Health column, "You Are Also What You Drink". The column focused on a report from a group of health and nutrition experts that looked at the relationship between beverage consumption and health. Among the points mentioned in the report, and appearing at the very end of the New York Times article, was "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."

This point was brought to the reference desk by Toytoy, who wondered, "What's going on in the United States that you don't have the freedom to make your soy milk more nutritious?" Some quick research indicated that the claim was cited to a journal article published in 1971. Whether or not it was true then that soy milk could not be legally fortified, it certainly is not true today—fortification is common and specifically recommended by the federal Food and Nutrition Service.

Among those responding was Jfarber, who called the mistake to the attention of Times editors. This ultimately produced the following correction posted 31 March: "The Personal Health column in Science Times on Tuesday about healthful beverages included incorrect information from the Beverage Guidance Panel about soy milk. It can indeed be legally fortified with vitamin D."

The process followed by the Times, in which the online version of the article was initially altered without any notice that the content had been changed, led to some further attention. Farber wondered about this procedure and reported his concerns to Boing Boing, which published them to a wider audience.

As explained by Times senior editor Greg Brock, the paper immediately updates online articles as soon as the error is confirmed. However, formal corrections such as the one quoted above run in the print edition of the paper, and the Times has a policy not to run them until the reporter or editor who made the error can be contacted. Once this is done, the correction is also appended to the online version, which in this case had already been "corrected" by simply ending the article's final paragraph prior to the erroneous passage.