Republicans who have tried for years to hamstring detailed surveys by the U.S. Census Bureau were suddenly alarmed Tuesday over news that changes to one of its surveys might in turn hamstring one of their political strategies -- attacks against Obamacare.

The changes, reported by The New York Times, will alter the questions asked about Americans' health insurance coverage, potentially making it more difficult to compare past and future data. The move comes as the country is shifting over to full implementation of the Affordable Care Act, and people on both sides of the debate would like to be able to point to solid data on how well it's working.

The problem, as the University of Minnesota School of Public Health's Kathleen Thiede Call told the Times, is that “The health insurance data reported in September of this year will not be directly comparable to what was reported last September.”

Republicans quickly took to Twitter to express alarm, and hint at conspiracies.

Here's the spokesman for House Majority Leader Eric Cantor (R-Va.):

It never stops. Obama Administration now changing the CENSUS survey in order to hide failure of Obamacare: http://t.co/1iXcMxWumw — Rory Cooper (@rorycooper) April 15, 2014

And a spokesman for House Speaker John Boehner (R-Ohio):

And an adviser for Sen. Ted Cruz (R-Texas):

As the Census Dept is tweaking their #'s to hide Obamacare, Commerce is trumpeting Big Gov't Data http://t.co/4Y2wUY3MLT — Amanda Carpenter (@amandacarpenter) April 15, 2014

Similarly, the National Republican Congressional Committee declared in a blog post: "Obama’s Census Bureau Is Changing How It Asks Health Care Questions To Hide The Effects of ObamaCare."

However, their fears are not entirely founded. A White House official noted that the next survey due to come out in September actually covers 2013, which means it will contain data from before the health care law went into effect. Vox.com explained this in more detail:

In other words: The survey will make it difficult to compare the uninsured rate for 2012, the last year for the old questions, and 2013, the first year for the new questions. But making the change now means that 2013 and 2014 –- the year before and after Obamacare's big programs started -– are using the same question set.

Census watchers are adamant that the change is not being made for political reasons, but to improve the data. "These changes are scientifically driven, but sometimes poorly timed," said Terri Ann Lowenthal, a former overseer of the Census for Congress and co-director of the Census Project.

Indeed, this particular change has been in the works for years, and was the subject of detailed, peer-reviewed studies. The most recent study from 2013 can be found here. Another study was conducted in 2010, and other studies and discussions go back as far as the early years of the George W. Bush administration.

In order for data to stay relevant, Lowenthal explained, surveys need to be modified and updated. "There has to be changes in questions, and frankly there may never be a good time," she said.

She also noted that the specific survey that is being altered is a supplement to the Current Population Survey, which produces, among other things, the jobless numbers. That survey is just one of several that collect health insurance data. It's also probably the least accurate.

If Republicans are worried that the books could be cooked in the Current Population Survey, and would like to rely on a different set of data entirely, they can fall back on the American Community Survey, which is far more detailed, and will continue to ask the same health insurance questions for several more years.

But if they really want to be able to look at the ACS data, the GOP will have to agree to stop trying to prevent the survey from being conducted.

UPDATE: The Census Bureau released a statement from Director John H. Thompson about the health insurance questions:

The recent changes to the Current Population Survey’s questions related to health insurance coverage is the culmination of 14 years of research and two national tests in 2010 and 2013 clearly showing the revised questions provide more precise measures of health insurance through improved respondent recall. This change was announced in September 2013 and implemented because the evidence showed that reengineering the questions provides demonstrably more accurate results. The Census Bureau only implements changes in survey methodology based on research, testing, and evidence presented for peer review. The revised questions were implemented in the Current Population Survey beginning in February 2014 in time for data collection covering calendar year 2013, and thus will provide a more accurate baseline for assessments of changes in insurance coverage, including that of the Affordable Care Act.