mentioned previously (EDK Associates, 1994), 84 percent of women surveyed were not concerned about acquiring an STD, including 72 percent of women from 18 through 24 years of age, and 78 percent of women reported having had ''many" sexual partners during their lifetime. Mays and Cochran (1988) reported on a study of African American college students who believed that African Americans were less likely to get AIDS than European Americans, even though the reverse is true. Of the sexually active women in the sample, almost a third had taken no actions to avoid STDs. Another nationwide survey of 1,000 persons in 1994 found that Americans underestimated their risk of STDs and were therefore not taking appropriate protective measures (EDK Associates, 1995). This survey found that 62 percent of men and 50 percent of women were at moderate to high risk for STDs (see Figure 4-3 for definitions of risk). Single and divorced men and women were most likely to be at high or moderate risk for STDs compared to married persons (Figure 4-3). Among those at high risk for STDs, 77 percent of women and 72 percent of men stated that they were not worried about getting an STD.
Perceived susceptibility has played a central role in most theories of health behavior (e.g., Wallston and Wallston, 1984; Weinstein, 1988). Perceiving one's personal susceptibility as low may arise from the experience of remaining STD- or HIV-free in the face of behavior that is known to be associated with a high risk of acquiring infection, such as engaging in anonymous unprotected sex with multiple partners over a prolonged period of time. Such perceptions may be reinforced by periodic negative testing. With consistent reinforcement of negative results in light of high-risk behavior, beliefs congruent with "genetic immunity" or "super invulnerability" may develop, leading to reduced motivation to adopt protective behaviors.
Knowledge is necessary but not sufficient to motivate action. Without knowledge, individuals may be unaware of risk or not know what actions to take to protect themselves against STDs. However, among those who do have sufficient knowledge, other factors will affect whether they take action. Thus, among populations with sufficient knowledge, knowledge itself is not related to the behavior (Morrison et al., 1994). Morrison and others (1994) studied adolescents who were incarcerated in the juvenile justice system. These adolescents, who reported engaging in high-risk sexual behaviors, had a good deal of knowledge regarding STDs and condoms, but this knowledge was not related to more positive attitudes toward use of condoms. Similarly, Wulfert and Wan (1993) found that college students with better knowledge about the HIV virus and how it is transmitted were no more likely to use condoms compared to those with less knowledge.
In virtually all behavioral theories regarding the reasons individuals either adopt or fail to adopt risk-avoidance strategies, reducing risk is viewed as a principal motivation of behavior (Cleary et al., 1986). Perceived risk is a critical component in the Health Belief Model (Becker and Maiman, 1975) and the Theory of Reasoned Action (Ajzen and Fishbein, 1980) and is reflected in outcome