The focal point of the present research was to assess and evaluate the effectiveness of HBM integrated with perceived social support variable in predicting disease-transmission preventive behaviors in HIV-positive patients, where the findings supported the adding of perceived social support variable construct to the HBM. In other words, the HBM developed by social support variable had better predictive power compared to the original model. This finding was in accordance with that of Bylund et al. study (
8). Similarly, Gillibrand and Stevenson in the UK found that this extended model is an adequate model for understanding the socio-psychological variables among young people, which influences adherence to the diabetes self-care behaviors (
16).
The present study indicated that social support variable was the second important factor influencing the preventive behaviors of HIV in patients. This is in line with the study of Masoudi and Farhadi showing that social support was the significant predictor of preventive behavior in HIV-positive patients (
17). Similarly, a study conducted by Chenary et al. among chemical veteran showed that there was a significant relationship between social support and health-promotion behaviors (
15). In addition, Malathum found that social support was a significant factor in predicting perceived abilities for health-promoting self-care among older adults in Thailand (
18). In another study, Qiao et al. concluded that policymakers needed to consider social support for female sex workers to protect them from HIV risks (Social support and condom use among female sex workers in China) (
10). However, a study by Bhatta and Liabsuetrakul showed that social support could be a useful asset among HIV-infected patients to promote their quality of life, decrease stigma, and increase adherence to antiretroviral treatment (
4).
Considering the effectiveness of social support and its relationship with preventive behaviors proved in this study and similar ones, and according to the WHO which believes that emotional and social support of HIV patients helps them to better cope with the disease and leads to increased personal inclination for treatment and control of the infection (
17,
19,
20), it is, therefore, recommended to design interventions for the patients’ relatives to promote their social support of the patients and encourage them to contribute to disease-transmission preventive behaviors.
In the present study, perceived barriers were the strongest predictive measure of preventive behaviors. Indeed, it is less likely to have preventive health behaviors if an HIV-positive patient perceived more barriers. A body of literature supports the role of perceived barriers in behavior change of people. For instance, a study conducted by Asare et al. on African immigrants in the U.S. revealed that the perceived barriers were significant predictors of safe sexual behaviors (
21). Similarly, a study by Zhao et al. among female sex workers in China showed that perceived barriers were the proximate determinant of condom use (
22). Moreover, in another study by Schnall et al. in the United States, it was revealed that perceived barriers were significantly associated with decisions to get tested for HIV (
9). Perceived barriers refer to the beliefs regarding the actual costs of following new behaviors. The reason behind such contradictions in the results of perceived barriers construct could be found in the diversity of perceived barriers such as physical and material barriers, or social and psychological barriers in different people and different behaviors. Barriers perceived by people could act against behaviors and cause people to do high-risk behaviors despite their awareness of prevention methods and practices.
Our findings revealed that self-efficacy of the patients could significantly predict their preventive behaviors. In other words, it is more probable to have preventive behaviors in patients with higher self-efficacy. Consistent with our study, several studies have documented, the relative impact of self-efficacy construct on preventive behaviors of disease transmission in HIV patients (
13,
23-
25). For instance, Asare et al. found that self-efficacy was a significant predictor of condom use among African immigrants (
21). In addition, a study carried out by Xiao et al. among young Chinese migrants underscored the importance of self-efficacy in HIV prevention interventions (
26). In addition, a study by Parriault among female sex workers in French Guiana showed that self-efficacy was central to condom use with intimate partners (
27). These results point to self-efficacy as an important benefit factor in reducing high-risk behaviors related to AIDS. Self-efficacy improvement is known as an intermediate goal for reducing HIV infection (
3). Self-efficacy is defined as the person’s confidence in his/her ability to follow a specific behavior. Previous studies showed that (
3,
26) self-efficacy plays a pivotal role in changing behaviors. Self-efficacy makes people pay more attention to environmental opportunities and be motivated to pursue their personal goals and take advantage of these opportunities. These people set challenging goals and strong commitments for themselves and in case of failure, they double their efforts (
19). The study by Buldeo and Gilbert showed that self-efficacy makes people try hard to reach their goals and resist the obstacles (
6).
The result of our study indicated that raising the level of perceived benefit is a significant factor to have preventive health behaviors in HIV positive patients. This result is in line with the findings obtained by Karimy et al., which showed that perceived benefit was a significant factor in predicting high-risk behaviors among drug users (
13). Similarly, a study by Nothling and Kagee among South African students showed that the perceived benefit was an important factor in the acceptability of routine HIV counseling and test (
28). The prediction of preventive behaviors through perceived benefits indicates that the potential benefits of preventive behaviors are well perceived by people, and we can move towards changing behaviors and employing safe behaviors in society by removing obstacles to following new behaviors; therefore, if a belief is established in educational interventions that the available preventive behavior is effective in reducing the severity of the disease and prevents the transmission of the disease to others, then people will follow the preventive behavior.
Concerning the socio-demographic variables, the results of this study showed that male patients compared to female patients had a better preventive behavior, higher scores of perceived self-efficacy and social support, and lower perceived barriers. These differences could be attributed to the specific nature of AIDS disease and its related stigma and cultural conditions of women in the study population that have higher social restrictions. Contrary to the findings of our study, in the study by Balali Meybodi, females had higher self-efficacy (
23,
29), which could be due to the difference between the study populations (HIV patients in this study) since infection with this disease has negative effects on the efficacy and self-esteem of patients, especially female patients.
Today, researchers believe that the education level is a more important predictor of health compared to other variables like age, income, employment status, or race (
30). In addition, in this study, people with higher education levels had better average scores in model constructs and preventive behaviors. This finding is in line with the study by Karimy on drug users in Zarandieh, which showed that people with higher education levels had a better attitude and performance in preventing AIDS (
13). Similarly, the study by Latkin and colleagues on injecting drug users in India showed that people with higher education levels had more awareness, and the prevalence of high-risk behaviors such as using shared syringes and needles was less common among them (
31).
In this study, married people had better self-efficacy, better perceived social support and benefits, and better preventive behaviors compared to single or divorced people. This was an expected finding since previous studies had shown that (
17,
20) family is the best place for supporting people infected and affected with AIDS, and family support contributes to better coping with the disease, promoting life quality, and preventing infection transmission. Similarly, the study by Masoudi showed that married people receive more social support than single people, and they use condoms for their sexual contacts more often than single people do (
17).
5.1. Conclusion
In this study, we surveyed an extended model of the HBM and found that this extended model predicted preventive behaviors better than original HBM did. In fact, the results from this study reinforced the idea that the HBM might benefit from being extended with social support. In other words, our findings highlighted a primary foundation to improve health intervention and information campaigns with the extended HBM. Similar studies are suggested in other places of the world to plan better HIV prevention intervention strategies.