The other day, the consulting company McKinsey released a startling study claiming that 30 percent of employers are planning to stop giving health insurance to their workers as a result of the Affordable Care Act. The study received a good deal of press coverage and was widely bandied about by conservative politicians and media outlets as proof that conservative warnings about the law are coming to pass.

But as a number of critics were quick to point out, McKinsey’s finding is at odds with many other studies — and the company did not release key portions of the study’s methodology, making it impossible to evaluate the study’s validity.

There’s now been a new twist in this story.

I’m told that the White House, as well as top Democrats on key House and Senate committees, have privately contacted McKinsey to ask for details on the study’s methodology. According to an Obama administration official and a source on the House Ways and Means Committee, the company refused.

A spokesperson for McKinsey — which does proprietary research regularly — declined comment.

The study’s topline conclusion was that 30 percent of employers will stop offering employer-sponsored insurance to employees in the years after 2014, when the health reform law fully kicks in. As the White House was quick to point out, this is an outlier: Other studies have concluded that health reform will produce minimal changes in whether employers will continue to provide coverage.

How did McKinsey conduct their study? An article accompanying the study claimed that 1300 employers of varying sizes, industries and regions had been surveyed. But there’s a good deal more we need to know about how it was conducted in order to verify its reliability. For instance, as Kate Pickert argued persuasively, a detailed breakdown of the sizes, locations and industries included in the survey would help us evaluate whether it’s “representative of American business as a whole.”

Also: The article about the study says it “educated respondents” about employer-sponsored insurance before asking them whether they would drop it after 2014. But we have no idea what that means or, more broadly, what question wording was employed in this study. Pickert asked McKinsley for more info about the methodology of the study. The company declined to comment. Politico asked McKinsey for the study’s question wording, and was turned down.

And yet, as Steve Benen pointed out, the study’s results are already on their way to becoming a key talking point against the Affordable Care Act.

Now the White House and top Congressional Democrats are asking the company to release the baseline information we need to evaluate the study’s credibility and integrity. So this story could now get a good deal more interesting.