A study published in the August 2007 issue of the Archives of Sexual Behavior offers what the authors purport to be the most comprehensive list of reasons people have sex that has ever been compiled.

While the list (which is really just a list of why young white college students have sex) is interesting and entertaining, I'm not sure it lives up to the researchers' claims or the sweeping generalizations made by uncritical media outlets who had a field day with headlines and gender stereotypes.

The study: In the first stage of the study, researchers asked 444 university students to list all the reasons they could think of to have sexual intercourse. Researchers compiled the results and whittled them down to a list of 237 reasons to have sex. They then asked about 1500 undergraduate students to consider each reason and indicate whether the reason describes the motivation behind none, a few, some, many, or all of their sexual experiences.

The findings: In the results, the researchers present the 237 reasons as ranked by men and women. After analyzing the responses, they proposed four larger categories that encompass all the reasons people have sex: physical reasons, goal attainment, emotional reasons, and insecurity.

The researchers point out that, of the top 25 reasons for having sex, 20 were the same for both men and women (although ranked in different order). Only six of the top 50 were ranked identically by men and women:

• Reason #1: I was attracted to the person
• Reason #6: I was sexually aroused and wanted the release
• Reason #7: I was "horny"
• Reason #15: It's exciting, adventurous
• Reason #19: The person really desired me
• Reason #32: I wanted to try new techniques or positions

The list is also notable for the variety of reasons given -- from the physical ("It feels good") or spiritual ("I wanted to feel closer to God") to the pragmatic ("someone offered me money") or spiteful ("I wanted to get even with someone"). Findings ranged from predictable to revealing:

• Men endorsed reasons that have to do with physical appearance and desirability (e.g. "The person had a desirable body") more than women.
• Men, more than women, endorsed reasons that had to do with wanting more sexual experiences or what they call "mere opportunity" to have sex (e.g. "The person was available"; "I wanted to increase the number of partners I had experienced.")
• Women endorsed reasons with emotional motivation for sex (e.g. "I wanted to express my love for the person") more than men.
• Men reported having sex to please a partner more than women.
• Men said they've had sex to gain social status or for practical reasons more than women.
• Men said they had sex to have an orgasm more than women.

Problems with the study: There are a variety of problems with this study and with the way it has been reported in the press. While these problems don't take away from the research, I think they indicate how complicated sex research can be and how careful researchers, journalists, and the rest of us need to be when comparing research to our own sexual experiences.

Some of the things to consider in this current study:

Who are "we"? The fact that the study participants were mostly white, young university students is a major limitation. One has to wonder why the investigators did not at least attempt to draw a more diverse sample, especially since they are claiming the resulting list is comprehensive. It's a shame that this point was buried in most of the mass media reporting and arguably downplayed in the paper itself.

The difference between asking and answering a question One of the drawbacks of this kind of research is its inability to address the differences in interpretation between the question asked and how it is answered. Consider the finding that more men said they had sex to have an orgasm than women. Given that men and women were remarkably similar in their top responses, and many responses included statements about experiencing physical pleasure, why would men be more likely than women to be motivated to have sex to have an orgasm? One reason could be that men are more likely to experience orgasms during heterosexual sexual intercourse, and as such, they expect it as a result. Since many women don't orgasm through intercourse, it is likely that it wouldn't be high on their list of reasons to have intercourse (we'll have to wait for the "reasons to have oral sex" study). In this case, the result about orgasm may tell us much more about the sexual experiences of participants than their sexual motivations. The results are framed as the researchers intended them to be understood -- not as the participants may have meant them.

Unanswered gender questions The researchers relied on gender as one of the fundamental constructs to explain their data. Unfortunately, they failed to adequately address the problems with this approach. They point to gender roles to explain the fact that men ranked most of the items with higher frequency than women, but don't address this same sort of bias in interpreting the lower-ranked results (which could very well be ranked lower because of response bias). And while an evolutionary psychologist would have no time for this comment, the authors fail to present a reasonable argument for gender being the primary variable of interest.

In the end, the study is an interesting one. It sheds some light on a topic that, as the authors point out, has received little scientific attention. We can only hope that, in the future, these questions will be taken up by researchers more willing to embrace a complicated population and explore conceptualizations of sexuality outside of their theoretical comfort zones.