Though statistics can be a source of clarity and hard evidence, they also can cause quite a fight. For evidence, look no further than conservative groups who have taken aim at a recent report about the changing role of American women at home and in the workplace.
The report in question is a May study from the Pew Research Center that found that women were the sole or primary earners in 40.4 percent of U.S. households with children under 18, as of 2011. That study gained widespread media attention, but some conservative groups say that headline statistic mischaracterizes women's place in the U.S. economy.
"This 41 percent number is at best misleading, and at worst, it's probably really sloppy research," said Sabrina Schaeffer, executive director of conservative advocacy group the Independent Women's Forum, at a Tuesday panel hosted by the conservative think tank Heritage Foundation. "Having come from the opinion research world, it is concerning ... that Pew is increasingly releasing things that are not as academically rigorous as they should be."
The 40 percent statistic, Schaeffer pointed out, largely consists of single mothers. Nearly two-thirds of homes where women are the primary or sole breadwinners are homes headed by single moms, while just over one-third percent are homes where a woman earns more than her husband. Both of these groups have grown dramatically over time. In 1960, just 3.5 percent of homes with children under 18 were headed by a married couple where the woman out-earned the man, and 7.3 percent of households with children under 18 were headed by single mothers.
A coauthor of the report points out that the critics are not quibbling with the numbers themselves, just with details about how the women are grouped.
"People may differ on what they make of these facts, but the numbers are accurate, the analysis is solid and it's all based on reliable data sources,” says Kim Parker, associate director of the Pew Research Center's Social & Demographic Trends Project. She adds that putting all of those women into one category is illuminating about the status of U.S. women. “Combining these demographically different groups into a single report makes a broader point: women's growing contribution to the economic well-being of families with children is a phenomenon that transcends race or class."
Still, detractors believe the way the study grouped mothers could have the power to shape the debate on women and work.
"In this case, and I fear in an increasing number of cases, the organization really did us a disservice by shaping the discussion for us as breadwinner moms, when the story is really as much about single moms as it is about women earning more," said Kay Hymowitz, senior fellow at the Manhattan Institute, a conservative think tank.
Pew has responded that the report did nothing more than dispassionately present the findings on breadwinner moms.
"We're pleased that our report was the basis for a thoughtful conversation about an important trend," says Vidya Krishnamurthy, communications director of the Pew Research Center, in an email to U.S. News, adding that the center never takes positions on whether the trends in its reports are good or bad.
Krishnamurthy adds, "We made it crystal clear that our report looks at single mothers and mothers who earn more than their husbands, and that society has differing views about this trend."
Indeed, Pew acknowledged in the third sentence of its study that breadwinner moms "are made up of two very different groups," noting that single-mom families earn a median of $23,000 per year, compared to $80,000 per year earned by families where both mothers and fathers work.
The Pew study also paints a picture of a nation not only where family dynamics are changing but where attitudes are as well. In 1997, 40 percent of respondents said it is better for a marriage if a husband out-earns his wife. Now, only 28 percent of respondents say so.
Updated 07/24/2013: This story was updated to include a quote from the Pew Research Center.