New sex-study method yields revealing answers

NEW YORK — It's a question that often prompts a boastful answer or a bashful one: How many sex partners have you had?

The federal government says it has authoritative statistics, documenting that men are far more likely to play the field than women.

A new nationwide survey, using high-tech methods to solicit candid answers on sexual activity and illegal-drug use, finds that 29 percent of U.S. men report having 15 or more female sexual partners in a lifetime, while 9 percent of women report having had sex with 15 or more men.

The median number of lifetime female sexual partners for men was seven; the median number of male partners for women was four.

The survey is based on data collected from 1999 to 2002 for the National Center for Health Statistics, a branch of the Centers for Disease Control and Prevention (CDC).

In previous versions, participants were questioned in face-to-face interviews. CDC officials think that caused underreporting of behaviors that might be viewed negatively.

This time, data were gathered from 6,237 adults, 20 to 59, in what are called computer-assisted self-interviews, a method designed to provide complete privacy and produce more honest answers.

"This is the first time we've used this technique," said Dr. Kathryn Porter, medical officer for the survey.

She said the findings would provide grist for further studies, notably on the prevalence and patterns of sexually transmitted diseases.

The questions about numbers of sexual partners specified heterosexual relationships, and thus the survey did not measure the extent of gay or lesbian sexual partnerships.

However, Porter said there was no such specificity in the questions about ever having had sex or about the age of first sexual activity, so answers to those could have referred to gays or lesbians.

The survey found only about 11 percent of never-married adults had remained chaste.

Among the other findings:

• About 96 percent of U.S. adults have had sex.

• Sixteen percent of adults first had sex before 15, while 15 percent abstained from sex until at least 21.

• The proportion of adults who first had sex before 15 was highest for non-Hispanic blacks (28 percent) compared with 14 percent for Mexican Americans and non-Hispanic whites.

• Six percent of blacks abstained from sex until 21 or older, less than Mexican Americans (17 percent) or non-Hispanic whites (15 percent).

• Black men and women were more likely to report having 15 or more partners in a lifetime (46 percent and 13 percent, respectively) than other racial or ethnic groups.

• Twenty-five percent of women and nearly 17 percent of men reported having no more than one partner of the other sex in their lifetime.

• Twenty-six percent of men and 17 percent of women have tried cocaine or other street drugs (not including marijuana). Seven percent of men and 4 percent of women had done so within the past 12 months.

• Non-Hispanic whites had a higher percentage of ever using cocaine or street drugs (23.5 percent) than blacks (18 percent) or Mexican Americans (16 percent).

The National Health and Nutrition Examination Survey did not include the homeless, prison inmates or other institutionalized adults.