Factors affecting Pakistani young adults’ intentions to uptake COVID‐19 vaccination: An extension of the theory of planned behavior

Abstract Introduction Aside from personal beliefs, young adults’ intention to uptake the COVID‐19 vaccine can be influenced by their fear of COVID‐19 and perceived infectability of COVID‐19. The present study incorporated fear of COVID‐19 and perceived infectability with the theory of planned behavior (TPB) to form an expanded TPB to analyze factors affecting Pakistani young adults’ intentions to uptake the COVID‐vaccine in Pakistan. Methods A cross‐sectional study was conducted and recruited participants from Pakistani social media users. The proposed extended TPB model was examined by using structural equation modeling. Results A total of 1034 individuals replied to the survey. The three factors of the original theory of planned behavior and the fear of COVID‐19 were positively related to their intention to uptake COVID‐19 vaccination (r = 0.25‐0.66). Moreover, the perceived infectability positively influenced the three theories of planned behavioral factors and the fear of COVID‐19 (r = 0.27‐0.60), also affecting the participants’ intentions to uptake COVID‐19 vaccination. Conclusions Perceived infectability was positively related to the participants’ intentions to uptake COVID‐19 vaccination, and perceived behavioral control was the strongest mediator. More evidence‐based information concerning treatments and COVID‐19 vaccination are needed to encourage individuals to uptake the vaccine.


Conclusions:
Perceived infectability was positively related to the participants' intentions to uptake COVID-19 vaccination, and perceived behavioral control was the strongest mediator. More evidence-based information concerning treatments and COVID-19 vaccination are needed to encourage individuals to uptake the vaccine. vaccination was effective in reducing the rate at which the disease spreads. However, not all individuals are willing to be vaccinated due to misleading information, complacency, the convenience of vaccine obtainment, and lack of confidence concerning vaccine safety (Fisher et al., 2020;Mercadante & Law, 2020). The refusal to uptake  vaccines may decrease the effectiveness of disease control and could threaten public health.
Interventions that use theory to develop healthy behaviors provide a valuable framework for accumulating evidence and may provide greater changes in health-related behavior (Prestwich et al., 2015).
The Theory of Planned Behavior (TPB) has been successful in predicting several health behaviors (Corace et al., 2016;Lin et al., 2018Lin et al., , 2017Lin et al., , 2016Schmid et al., 2017;Strong et al., 2018;Xiao & Wong, 2020). The TPB was adapted from the Theory of Reasoned Action to understand and predict whether an individual would take a specific action (Ajzen, 1991 (Yahaghi et al., 2021). The PMT is a health psychological theory and was developed to explain the cognitive mediation process of behavioral change from the perspective of threat and coping appraisal (Rogers, 1975;Rogers & Prentice-Dunn, 1997). The PMT's threat appraisal component contains two major elements: perceived severity and perceived vulnerability, which are affected by fear of disease. The coping appraisal comprises the following: response efficacy (i.e., the judgments whether accomplish an action can decrease the threat), self-efficacy (i.e., the confidence that an individual has abilities to take action to protect themselves), and response cost (i.e., the cost related to take action to remove the threat) (Norman et al., 2005).
In this case, fear of disease (i.e.,  can be reflected by how individuals consider severity of having COVID-19 and the ability to cope with it. Perceived vulnerability means the perceived infectability of COVID-19. The present study supplemented the PMT elements of fear and perceived infectability to the TPB for maximizing the efficiency in explaining individual's intention to be vaccinated for COVID-19 infection. Some studies have found that perceived vulnerability increases individuals' positive attitude toward the behavior to prevent the threat (Pang, Tan, & Lau, 2021), and trigger their review of the environment, resources, and self-efficacy to take protective action (Najafi et al., 2017). Moreover, when individuals feel more vulnerable, they may tend to accept significant others' opinion in protecting themselves.

Participants and procedure
A cross-sectional study was conducted among social media users in  (Rogers, 1975). The measures on fear of COVID-19 in the present study had satisfactory psychometric properties: α = 0.899; CR = 0.892; and AVE = 0.544.

Data analysis
The participants' characteristics were firstly analyzed using descriptive statistics including means and frequencies. Pearson correlations were used to examine the associations between every two tested constructs proposed in the model.

RESULTS
The study sample comprised more females (n = 743; 71.9%) than males (n = 291; 28.1%) and had a relatively young age (mean = 22.17 years; SD = 6.36). The majority of the participants had a degree (23.5% postgraduate and 48.0% undergraduate). Less than one-fifth of the participants were currently married (13.3%). Very few participants had been infected by the COVID-19 (3.7%) and even fewer participants had been hospitalized due to COVID-19 (1.5%) ( Table 1). In the results of CFA, all factor loadings of the items used in the pro- Furthermore, Table 4 shows that the mediated effects were significant (standardized coefficient = 0.305; 95% CI = 0.487-0.734; p < 0.001), which indicated that attitude, subjective norms, perceived behavioral control, and fear of COVID-19 mediated the association between perceived infectability and intention to vaccination uptake. The results of the SEM analysis stratified by gender were similar to the model including all participants (Supporting information Figure S1). A previous study appears to support the findings of the present study.

DISCUSSION
It found that some individuals felt that others had a higher risk of getting COVID-19 infection and were more in need of COVID-19 vaccination than themselves, so that they decided not to get vaccinated (Rieger, 2021). Surprisingly, individual's fear of COVID-19 appears to be less influential than the other three factors. A previous study also found that trusting the safety of the vaccine was a stronger factor in predicting COVID-19 vaccination intentions than the fear of COVID-19 (Karlsson et al., 2021). In other words, an individual's attitude to get vaccine and perceived behavioral control were more influential.
The results showed that perceived infectability was related to participant attitude, subjective norms, perceived behavioral control, and fear of COVID-19. The fear of disease comes from perceived threats (i.e., perceived susceptibility and perceived severity), and it has been verified as a crucial factor in taking action (Corrigan et al., 2014;Weston et al., 2020). The individual's attitude, and the judgment to vaccinate or not, can reflect the degree of perceived infectability. Perceived infectability also activates the individual's perceived behavioral control in reviewing the capability and resources to overcome the disease. Moreover, the effects of the subjective norm may be elevated by the increase of perceived infectability. For example, individuals might follow their significant others' opinion to keep distance from the community to reduce the spread of COVID-19 when they feel more threatened (i.e., higher perceived infectability) and do not know what to do (Alijanzadeh & Harati, 2021). In short, the perceived infectability influences the intention to get COVID-19 vaccinated through the four mediators: participant' attitude, subjective norms, perceived behavioral control, and fear of COVID-19.
The study found that perceived behavioral control was the strongest mediator in intention to be vaccinated, and the fear of COVID-19 was the least strong. This situation was consistent with previous studies concerning applications of behavioral change. In the TPB, perceived behavioral control comprises perceived self-efficacy and perceived controllability (Ajzen, 2002). Self-efficacy has been found to be an important predictor in the application of health behavioral change Std. coefficient , Standardized coefficient. (Kelly et al., 1991;Strecher et al., 1986). Without self-efficacy, the explained variance of the entire model was reduced. In addition, fear of disease may appear to lead to preventive actions at first glance, but a fear strategy may not be effective and may even be counterproductive (Shen, 2011). For example, warnings that smoking can cause lung cancer may increase anxiety and make individuals smoke more often.
Therefore, some scholars have begun to call on health authorities not to use fear appeals in the health communication of COVID-19 prevention (Stolow et al., 2020).
The present study has two key implications. First, subjective norm was quite related to intention of COVID-19 vaccination uptake, indicating that health providers need to provide more evidence concerning safety and effectiveness of COVID-19 vaccines and emphasize the benefits to individuals and the population. Therefore, the subjective norm would lead to positive reasons to vaccinate. Second, the perceived infectability had a significant impact on individuals' vaccination intention, which means that the readable information concerning the incidence and prevalence of the COVID-19 are necessary to help individuals to link the information to themselves.
The present study has three major limitations. First, the participants of this study were recruited via the internet, and they were younger than the mean age of the Pakistan population. Second, the proportion of female participants was much higher than the proportion of men.
However, the results showed that the loadings of SEM were similar in both genders. Therefore, the gender imbalance might not be a critical issue in relation to generalization. Third, the participants in the present study were younger and more educated than the average of the national Pakistani population. Therefore, the results cannot be generalized to older and lower educated populations in Pakistan. These limitations may hamper the representativeness and interpretation of the study's results.

CONCLUSIONS
Perceived infectability was positively related to the participants' intentions to uptake the COVID-19 vaccine, and perceived behavioral control was the strongest mediator. More evidence-based information concerning the treatments and COVID-19 vaccination are needed to encourage individuals to uptake the vaccine.

CONFLICT OF INTEREST
The authors declare that they have no conflict of interest.

DATA AVAILABILITY STATEMENT
The data that support the findings of this study are available from the corresponding author upon reasonable request.