This 18-item scale was developed by the Kinsey Institute to measure American's basic sexual knowledge. It was originally administered to 1,974 American adults in the fall of 1989 and became know as the "sex test America failed." In fact, 55% of American adults failed this knowledge test.

Here is an opportunity to test your sex knowledge and compare your responses to the national sample. Please select one answer after reading each question carefully. Once you have completed the 18 items, click CALCULATE.

1. Nowadays, what do you think is the age at which the average or typical American first has sexual intercourse?
2. Out of every ten married American men, how many would you estimate have had an extramarital affair- that is, have been sexually unfaithful to their wives?
3. Out of every ten American women, how many would you estimate have had anal (rectal) intercourse?
4. A person can get HIV by having anal (rectal) intercourse even if neither partner is infected with the AIDS virus.
5. There are over-the-counter spermicides people can buy at the drugstore that will kill the AIDS virus.
6. Petroleum jelly, Vaseline Intensive Care, baby oil, and Nivea are not good lubricants to use with a condom or diaphragm.
7. More than one out of four (25 percent) of American men have had a sexual experience with another male during their teenage or adult years.
8. It is usually difficult to tell whether people are or are not homosexual just by their appearance or gestures.
9. A woman or teenage girl can get pregnant during her menstrual flow (her "period").
10. A woman or teenage girl can get pregnant even if the man withdraws his penis before he ejaculates (before he "comes").
11. Unless they are having sex, women do not need to have regular gynecological examinations.
12. Teenage boys should examine their testicles ("balls") regularly just as women self-examine their breasts for lumps.
13. Problems with erection are most often started by a physical problem.
14. Almost all erection problems can be successfully treated.
15. Menopause, or change of life as it is often called, does not cause most women to lose interest in sex.
16. Out of every ten American women, how many would you estimate have masturbated either as children or after they were grown up?
17. What do you think is the length of the average man's erect penis?
18. Most women prefer a sexual partner with a larger than average penis.

Source: Reinisch, J. M. (1990). The Kinsey Institute New Report on Sex. New York: St. Martin's Press.