The present study aimed to investigate the relevant and changeable psychosocial determinants that contribute to the intention and past year BSE behavior. The study included variables from the RAA  and HBM  as well as variables informed by findings of previous qualitative studies [16, 18]. Knowledge gained from the current study can inform interventions that aim to promote regular BSE practice by targeting the main explanatory factors of the (non-) performance of this preventative behavior. The results indicate that regular BSE on a monthly basis in the past year was not prevalent among the respondents, which is consistent with the previous study . Additionally, the likelihood of performing BSE behavior in the past year was associated with adequate knowledge about breast cancer and positive attitudes towards BSE. Together, the two variables explained approximately 33.3% of the variance in BSE behavior.
In line with previous findings [16, 18], the current data demonstrated that breast cancer knowledge is a correlate of BSE behavior. Thus, the higher the respondents’ understanding of the nature of breast cancer in terms of definition, symptoms, risk factors, and screening modalities, the higher the likelihood they performed BSE in the past year. In the same manner, previous studies on women populations in Iran, Ghana, and Nigeria confirmed that adequate knowledge of breast cancer significantly improves the likelihood of women to perform BSE [22,23,24]. Together, the findings that (a) knowledge about breast cancer serves as a unique predictor of BSE performance and (b) the low rates of regular BSE practice in the current sample, imply that low BSE performance may be due to the lack of breast cancer knowledge. This conclusion is in line with that of Didarloo et al. , who conducted a study among students in Iran and found that respondents with high levels of knowledge about breast cancer performed BSE 5.51 times more than those with low levels of knowledge. This finding highlights the necessity of improving breast cancer literacy among Indonesian women and the need to support education on breast cancer screening.
As noted by Bartholomew Eldredge et al. , knowledge does not directly lead to a behavior change; women’s understanding of breast cancer alone is insufficient for the management of a BSE behavior. Ajzen et al.  suggested that a more positive attitude towards a health behavior play a major role in facilitating such a behavior. In line with these suggestions, the current study finds that women with positive attitudes towards BSE were 2.08 times more likely to perform the behavior than women with negative attitudes. This finding supports previous research among Indian–Australian women, which reported that respondents with positive attitudes towards general check-ups regularly practiced breast screening as recommended . Conversely, women with a negative perception of BSE felt embarrassed to perform it or experienced difficulty in performing were less likely to perform BSE. This result is in line with that of Al-Dubai et al., , who proposed that a negative attitude towards BSE will impede BSE behavior.
The intention to perform BSE regularly among respondents was relatively high. However, only 7.8% and 2.9% of the respondents indicated that they performed BSE regularly (monthly and weekly, respectively). Additionally, although the intention was positively correlated with BSE behavior, the measure of intention failed to explain any unique variance in BSE behavior. This finding supported intention–behavior gap hypothesis, i.e., participants with positive intentions failed to perform the behavior . Moreover, the current data indicated that the 32.2% of variance in intention to perform BSE was predicted by the positive attitudes towards BSE and a high PBC. Thus, the study concluded that women who perceived BSE as an important process and were able to perform it were more likely to report increased intention to perform such. This finding aligns with those of Wang et al. , who conducted a study in China, and concluded that behavioral attitude was one of the unique correlates of intention to perform breast cancer screening. Additionally, the current finding that women who felt confident with their autonomy and capacity to perform BSE indicated high levels of intention to perform such is in line with that of Roncancio et al.  on Latinas. The authors documented that PBC was a strong predictor of the intention to be screened for cervical cancer.
Several changeable psychosocial variables, i.e., perceived benefits, perceived barriers and subjective norms failed to explain the unique variances of intention and BSE behavior. However, in the bivariate correlation analysis, these variables were significantly associated with intention to perform BSE and BSE behavior. Similarly, previous studies reported evidence that if women perceived BSE as highly beneficial, they would be more likely to form positive intentions and/or perform BSE [17, 22, 30]. Vice versa, intention and/or BSE behavior would be less likely to occur when women perceived certain obstacles in BSE performance [17, 32, 33]. Additionally, a strong family support system characterized the Indonesian population . Thus, the notion that women’s breast cancer screening behavior would be influenced by the support they (perceive to) receive from their close social circles is not surprising. Indeed, a previous study highlighted the significance of subjective norms, such as encouragement from daughters or relatives, to participate in breast screening . Moreover, Cho and Lee  found that, in general, individuals from collectivistic cultures (i.e., Indonesia) score higher on subjective norms compare to those of individualistic culture. Therefore, the study suggests that developers of programs or interventions should focus on the role of subjective norms in the transmission of information about the advantages of performing BSE. Moreover, developers should formulate strategies for overcoming barriers to BSE performance during education on breast cancer awareness, e.g., involving women’s close friends or family in health education activities.
The study was interested in exploring the distribution of demographic and psychosocial determinants among women who performed BSE in the past year (compared with non-performers). The results indicated that women who performed BSE in the past year reported higher levels of intention to perform BSE, positive attitudes towards BSE and breast cancer (i.e., they feel that breast cancer is not related to moral wrongdoing or a taboo topic), subjective norms, and PBC compared with those of non-performers. Furthermore, BSE performers were found to possess a better understanding of breast cancer and were more likely to perceive that performing BSE is beneficial for them. Interestingly, the study also found that women who performed BSE viewed more obstacles to BSE performance compared with those who did not perform BSE. The study inferred that BSE performers gained a more realistic view of BSE performance but found it important, nonetheless, which contributed to their decision to perform. Moreover, in line with previous research, younger women were less likely to perform BSE compared with older women, perhaps because they perceived lower risk of or susceptibility to breast cancer .