In this study, we found women had more accurate knowledge about cancer than men, that the accuracy increased with increasing levels of educational attainment and annual household income, and that never smokers had more accurate knowledge than current or former smokers. In addition, we found significant differences in the accuracy based on the participants’ health beliefs, indicating that accurate knowledge about cancer is associated with different types of health beliefs. Specifically, more accurate knowledge was associated with protective health beliefs.
Consistent with the literature, we found that women had more accurate knowledge than men.4,19
This finding might reflect sex-specific societal norms and definitions of masculine and feminine attributes. According to Courtenay,20
societal expectations of men and women affect their health behaviors. For example, masculinity is characterized by being strong, tough, and invulnerable to disseases, suggesting that men need not be concerned about their health, which is usually considered a feminine attribute; whereas women’s roles in caregiving and child rearing are more associated with health concerns. Therefore, such sex-related distinctions in social expectations may account for the differences in intentions to acquire accurate knowledge.
We also found that as educational attainment and household income increased, so did the accuracy of cancer knowledge, consistent with previous studies.3,4
For example, Gansler et al3
found that higher educational attainment and higher annual household incomes were associated with more accurate knowledge about cancer treatment, whereas Viswanath et al21
found that higher levels of education and income significantly predicted a better understanding of the association between smoking and cancer. Viswanath et al21
underscored the important role the media (particularly print media) can play in attenuating these gaps in knowledge. However, although the media plays a crucial role in the dissemination of cancer information, people with low levels of education may not realize these benefits because they rely heavily on the media for entertainment rather than for education.22
The relationship we observed between smoking status and accuracy of knowledge was not surprising. As expected, and consistent with previous research,23
never smokers demonstrated more accurate knowledge than current smokers. Interestingly, the level of knowledge we observed among former smokers was similar to that among the never smokers. Perhaps this higher level of knowledge contributed to the former smokers’ decisions and ability to successfully quit.
In contrast to the literature, we did not find a significant link between race/ethnicity and the accuracy of their knowledge. Previous studies have drawn attention to the fact that different racial/ethnic groups report different levels of cancer,23
but our study did not support this conclusion. However, in some of these previous studies, the analyses did not control for other demographic characteristics such as educational attainment and household income.24
Because ethnicity and SES are confounded, it is not clear from the previous studies which factor is more strongly associated with more accurate knowledge. We found that after controlling for SES, an important determinant of health,25
the racial/ethnic-based differences in accuracy disappeared (P
= .90). This suggests that the unadjusted racial/ethnic-based variation was attributable to underlying differences in SES status. Therefore, our result is consistent with a finding from a study conducted by Price, Sherry, and Everett,3
which examined cancer knowledge in an economically disadvantaged yet ethnically diverse population and found that higher levels of education were associated with fewer misconceptions about cancer than lower levels of education.
With regard to the influence of health beliefs on health behaviors, the overall results supported our hypothesis that accurate knowledge is associated with protective health beliefs. In particular, among men, accurate knowledge was associated with normative beliefs, social norms, self-efficacy, need for social support, and outcome expectations but not perceived severity. Our findings support the links between knowledge and health beliefs because we found that men who endorse protective health beliefs hold more accurate knowledge. Surprisingly, among women, accurate knowledge was associated with only outcome expectations and perceived severity. As suggested by Courtenay,20
women are inclined to be concerned about their health as a result of their caregiving roles in society and therefore are probably less influenced by these specific health beliefs. However, because ours was a cross-sectional study, we were unable to determine the causal direction of the relationships between accurate knowledge and health beliefs. Future research using a longitudinal design will be necessary to assess whether changes in knowledge influence changes in beliefs or vice a versa to ultimately influence changes in behavior.
This study has certain limitations. Our study examined knowledge about cancer among English-speaking African American, Hispanic, and non-Hispanic white participants; therefore, the results may not generalize to members of other minority groups. However, although most of our participants were non-Hispanic white, our results did not indicate any ethnic differences in cancer knowledge, indicating that these results could be generalized to other populations. In addition, the health beliefs we examined did not focus on a specific behavior, such as smoking, which prevented us from examining the relationships between knowledge, beliefs, and behavior. Although we examined certain health beliefs that, in theory, influence protective behaviors, it was beyond the scope of this study to complete a comprehensive analysis of all the theoretical constructs such as attitudes and perceived susceptibility. Furthermore, the constructs assessed were based on a single item rather than a cluster of items. However, some studies have demonstrated that a single item can be as reliable and valid an assessment as a cluster.26
Finally, the cross-sectional design of the study limited our ability to draw conclusions about causality.
In conclusion, we found differences in accuracy of cancer knowledge by gender, SES, and smoking status but not ethnicity or age. Therefore, the results of our study can be used to inform the development of health promotion programs. They underscore the continued need for health education messages to target people from low SES groups and current smokers. In addition, because it is widely known that men have less-accurate health knowledge than women, our results emphasize the need to develop health education messages that target men to increase their knowledge and awareness about male cancers. Finally, our results also suggest that addressing the links between knowledge and health beliefs would provide valuable resources when implementing health promotion programs to facilitate the adoption of protective health behaviors. This study underscores the continued need for health education messages designed to increase cancer knowledge among men, people from low SES groups, and current smokers. The results further suggest that addressing health beliefs as well as knowledge could facilitate the adoption of protective health behaviors.