Correction to our report of a contraceptive study

An anonymous visitor used our “Report an Error” feature on Dec. 14, 2014:

Please describe the error: You cite a study that finds:

“researchers from Washington University in fact observed a statistically significant decrease in the number of sexual partners participants reported”

Then you conclude that:

“The study from the Contraceptive Choice Project gives some weak evidence that free contraception results in more promiscuous sex habits.”

The error: The Contraceptive Choice Project does NOT give any evidence that free contraception results in more promiscuous sex habits. In fact, it shows a decrease in sexual partners. I would respectfully request that you correct this page.
URL location of error: http://www.zebrafactcheck.com/free-contraception-promiscuity/
Don’t mention my name if you do a correction (keep me anonymous): Yes

 

The complaint is partially correct.

We based our original conclusion about the study on the abstract:

“CONCLUSION: We found little evidence to support concerns of increased sexual risk-taking behavior subsequent to greater access to no-cost contraception.”

 

But we apparently made a mistake in taking the abstract literally about its “little evidence” claim, though we also considered this aspect of the study:

In total, 70% to 71% of women reported no change in their number of sexual partners in the past month, while 16% reported an increase and 13% to 14% reported a decrease.

 

This reporting of the study says a net of about 2 percent of the study participants reported an increase in the number of sexual partners. It’s misleading to say the study showed a decrease in the number of sexual partners for women getting free contraception.

While attempting to verify the legitimacy of the error complaint, we ran across a statement from the study’s lead researcher, Gina Secura, that we overlooked earlier (bold emphasis added):

Secura said that although the study did not compare no-cost contraceptive recipients with a control group to see if there were differences in behavior, the findings should dispel “the idea that the only thing standing between women and promiscuity is a fear of pregnancy” (USA Today, 3/7).

 

The lack of a control group does undermine our suggestion that the study provides weak evidence of increased promiscuity. It also undermines a literal interpretation of the study’s abstract, the LA Times’ summary of the study, and even Secura’s claim above about what the study should dispel. Such a study, with no control group, has very limited scientific usefulness in supporting any conclusion at all. Such studies are called quasi-experimental studies.

The complaint that the study shows a decrease in sexual partners refers to a comparison of the treatment group before and after providing free access to contraceptives. It provides no scientific support for the claim free contraception does not encourage promiscuity. Moreover, that statistic only applies to the number of women reporting more than one sexual partner over the 30 days preceding the surveys. Taking women who increased from zero partners to one into account, slightly more women increased their number of sexual partners than decreased.

The study doesn’t measure whether women changed partners more often over a longer span of time, such as six months, after receiving free contraception.

Changes

We altered two sections of our fact check in light of our re-examination of Secura’s work. We revised a section of two lines sandwiching a quotation just before our “Conclusion” section. Here’s the original, in bold:

The kicker? The study’s conclusion differed from the Times’ version:

CONCLUSION: We found little evidence to support concerns of increased sexual risk-taking behavior subsequent to greater access to no-cost contraception.

We don’t think “no” serves as a proper substitute for “little.”

We replaced that section with this:

Of even greater concern, the Contraceptive Choice Project study employed no control group. As such, it counts as quasi-experimental research and offers no real support for the DNC’s claim.

 

We also changed our concluding paragraph by omitting the last sentence. Here’s the original concluding paragraph:

Free contraception certainly expands free rein for students to engage in promiscuous sex.  Whether they take advantage of the free rein is another matter.  The study from the Contraceptive Choice Project gives some weak evidence that free contraception results in more promiscuous sex habits.

 

The new version omits the last sentence, of course. We’ll skip the step of reproducing the new version here.

Thanks to our anonymous reader for helping to improve our fact check.