Extramarital Affairs: An Exaggerated Myth.

• Author: WIEDERMAN, MICHAEL W.

Surveys show that the incidence of sexual affairs is far less than suggested by Hollywood and adult magazines.

"HALF of all married men and women in America have extramarital sex," shouts the talk show host. As you stare at the television set, you ask, "Could it be true? Are half of the married people I know fooling around?" If you yourself have not engaged in extramarital sex, you might wonder whether you are missing out on a more-or-less normative experience. Of course, it is necessary to ask where these "facts and figures" came from and what social scientists actually know about extramarital sex in America.

Researcher Alfred Kinsey and his colleagues, in their monumental sex surveys conducted primarily during the 1940s, were among the first to ask Americans about such experiences. Based on their cumulative findings, Kinsey projected that approximately one-half of married men and one-third of married women eventually would have extramarital sex. Kinsey's sample, although relatively large, was far from being representative of the U.S. population. Nevertheless, that is where the mythical figure of "one-half" was born.

During the 1970s and early 1980s, several less-than-scientific surveys were conducted on Americans' sexual experiences, including extramarital sex. Many of these large-scale studies were done via surveys in magazines that asked readers to tear out, complete, and mail the questionnaire to the publisher. In some of these magazine surveys, the majority of respondents indicated that they indeed had engaged in extramarital sex. However, there are tremendous sampling problems in such studies, with the most likely result being an overrepresentation of non-normative behavior. For one, such "racy" surveys often were included in magazines aimed at a more sexually oriented audience (e.g., Playboy, Cosmopolitan). Even among this readership, people who had not had the experiences asked about probably were least likely to complete the survey, thinking "What's the point of wasting my time?"

More recently, social scientists have had access to data on American sexual behavior gathered using state-of-the-art sampling procedures. For instance, the National Opinion Research Center, housed at the University of Chicago, conducts a biannual large-scale survey of Americans. This project, the General Social Survey, consists of face-to-face interviews with adults sampled so as to be representative of the noninstitutionalized population of the U.S. The focus is a host of demographic and public opinion items, not sexuality. In the last several General Social Surveys, though, a self-administered questionnaire having to do with basic sexual experiences was included at the end of the interview. Respondents were instructed to complete the brief questionnaire while the interviewer waited, seal it in the envelope provided, and return it to the interviewer, who would forward the sealed envelope to the researchers.

In the survey conducted in 1994, respondents were asked, "Have you ever had extramarital sex?" Although the question doesn't provide any specific information about the nature of, or circumstances surrounding, the act, it at least provides a baseline for the proportion of Americans who admit to having engaged in...