Vaccines to protect against sexually transmitted diseases including HIV and herpes are under-development.
A University of Missouri researcher has found that college students who believe they are invincible are unlikely to get such vaccines.
On the other hand, students who feel invulnerable to psychological harm are more likely to get the vaccine.
"Previous researchers have used invulnerability measures to predict health-endangering behaviors in students, but this study is unique in that it considers the role of invulnerability in students' health-protective or preventative behaviors," said Russell Ravert, assistant professor in the MU College of Human Environmental Sciences.
For the study, Ravert measured two invulnerability factors danger and psychological.
He observed that students with increased danger invulnerability, those who viewed themselves as physically invincible, were more likely to decline the vaccine.
Ravert said that one explanation of such an attitude is that strong feelings of danger invulnerability may be associated with decreased threat, which can diminish protective behaviors.
Students who felt psychological invulnerability, those who didn't care what others thought, were more likely to accept a vaccine.
According to Ravert, students' psychological invulnerability may protect against the possible stigma associated with getting vaccinated for HIV, or other sexually transmitted diseases.
"It is important to determine what factors are associated with vaccine acceptance because not all students will be willing to take vaccines. Efforts to promote vaccines should consider that students who aren't worried about being harmed are less likely to get the vaccine, even when it's warranted by their sexual behavior," said Ravert.
The researchers found that the strongest predictor of vaccine acceptance in the study was students' perceived susceptibility to contracting HIV, followed by their number of sexual partners.
Students' decisions also were influenced by the cost of the vaccine.
The study was published in the latest issue of the American Journal of Health Behavior.