Hayat Bhatti et al. (2019) believed that in the foundation of trust, employees have the willingness to demonstrate OCB because they believe that the organization or managers will have peer feedback after their efforts. The Qi et al.’s (2019) study pointed out that based on the exchange norm of reciprocity, when employees perceive organizational support, they develop a sense of obligation to help the organization achieve its goals. Because from the perspective of social exchange theory, when employees feel the help of the organization, they will give back to the organization with harder hard work and loyalty, or help employees in difficulty. Perceived organizational support comes from how employees attribute and judge how the organization treats them (Silva et al., 2022). Therefore, when members who join an organization feel considered as part of the organization and are highly valued, employees will feel that they have a responsibility to contribute adequately to the organization to provide the best performance for the organization (Kristiani et al., 2019).

Based on the above, studies have shown that based on the reciprocal norm, employees who perceive support from their organization tend to feel obligated to help their organization achieve its goal (Thompson et al., 2020). According to the social exchange theory, employees who perceive organizational support will work harder and be more loyal to the organization in return (Imran et al., 2020). Therefore, the employees of an organization who perceive themselves as being treated as members of their organization and valued by their organization will consider themselves responsible for making as many contributions as possible to their organization; so the organization can perform its best (Ridwan et al., 2020). In additional, the psychological mechanism of employees’ perception of their organization’s loyalty (commitment) is related to the concept of social exchange and a psychological contract between employees and their organization (Garcia et al., 2021). POS is capable of affecting employees’ work attitude and behavior through the effort-anticipated reward association and the reinforcement of personal social emotional need (Shabbir et al., 2021). Consequently, organizations can use employees’ POS to boost their OCB. Moreover, according to the social exchange theory and the reciprocal norm, employees develop a general belief assessing the extent to which their organization values their contributions and wellbeing. Employees perceiving a trustworthy relationship with their organization are likely to demonstrate OCB (Kurtessis et al., 2017; Aboramadan et al., 2022).

According to the above ideas, this study proposed the first hypothesis:

Han et al. (2019) suggested that by offering incentives, organizations can elicit employees’ OCB. Therefore, when an organization cares about its employees’ wellbeing, values their contributions, and provides favorable work conditions, its employees will perceive organizational support and appreciate the organization. These employees will also show a strong sense of obligation, which prompts them to exhibit OCB in return (Thompson et al., 2020). Parker and Axtell (2001) proposed the perspective taking theory and suggested that the effect of taking the perspective of other people would change an employee’s original traits and dispositions, and the magnitude of the change depends upon the person’s motivation (Škerlavaj et al., 2018). Within an individual’s scope of work, the social motivation of volunteering directly benefits other people while improving one’s work performance and the drive to succeed, and therefore, it is OCB-related (Robison, 2022). Moreover, people with perspective taking can put themselves in others’ position to understand and feel the thoughts and ideas of others, so as to form a motivation to help others and promote them to show more altruistic behaviors, such as OCB (Sabati, 2022). Therefore, in the influence of POS on OCB, if the voluntary service with altruistic motives of volunteers can be used as perspective taking, the organization’s support for them can be better understood, which will eventually increase OCB (Kim et al., 2019). Furthermore, studies have shown that employees showing a stronger volunteer participation motivation are likely to be more engaged at work and more satisfied with their work (Dal Corso et al., 2019). In terms of engagement motivations, the key motivations are interpersonal interaction, serving others, knowledge acquisition, and keeping in touch with society (Arai, 2000). Researchers have discovered that volunteering is an engagement behavior based on social responsibility; it is a virtue of helping other people and an organizational altruistic behavior (Ficapal-Cusí et al., 2020).

Taken together, employees who perceive themselves as well-treated by their organization will in return demonstrate citizenship behavior beneficial to their organization. This mentality of reciprocation or exchange will affect employees’ attitude toward their organization and reflect on their work attitude or behavior. Therefore, POS and volunteer participation motivation will affect OCB via different social exchange routes, and employees’ volunteer activities have a positive catalytic effect on the relationship between POS and OCB. In other words, POS can positively affect employees’ OCB performance through the interaction with volunteer participation motivation.

According to the ideas above, the second hypothesis was proposed as follows:

The leader of an organization plays a key role in affecting the work environment and employees’ perception of work (Pancasila et al., 2020). Avolio et al. (1999) pointed out that transformational leaders would apply their influence to integrate leader-subordinate interactions. At the same time, they would offer personalized care, stimulate employees intellectually, and establish an interactive and creative process between leaders and their followers through motivation and spiritual inspiration. By doing so, they would encourage employees, win their admiration, respect and honesty, and aggregate the power from their followers, which together will promote group cohesion (Jiang and Chen, 2018). Some studies have shown that transformational leaders with a good leadership style can boost employees’ confidence in other team members, and employees will believe that their team members will offer help when they are in need. This will therefore improve team cohesiveness (Asgari et al., 2020). According to the above findings, transformational leadership cultivates group identification and cohesion, links team members together, and consequently affects organizational climate (Mach et al., 2022).

As a result, the third hypothesis was proposed:

Research has shown that transformational leaders can inspire those around them to emphasize a vision of group interests (Veríssimo and Lacerda, 2015), create a committed work climate, empower their followers, and provide sufficient support to achieve innovation at work (Astuty and Udin, 2020). In addition, a leader with a transformational leadership style tends to motivate his/her subordinates to exceed their expected output by changing their vision, being role models, providing support and inspiring their desire to change for the better (Suifan et al., 2018). Furthermore, a study has shown that transformational leadership encourages people to value a common interest-based vision (Guarana and Avolio, 2022). It also creates a work climate for organizational identification, supports and encourages subordinates, and spreads the organization’s vision thereby making employees feel emotionally connected to the organization and identify themselves with the organization (Dinc et al., 2022; Du and Yan, 2022). At the same time, employees are encouraged to bear more responsibility for the development of positive motivation and altruistic behavior (Astuty and Udin, 2020). Based on the previous mentions, transformational leadership styles will have a great impact on how subordinates act (Shofiyuddin et al., 2021), such as improving POS and showing more OCB (Bacha and Kosa, 2022).

Managers and other leaders in an organization have a critical influence on organizational incentives. For example, transformational leaders can timely provide employees with the resources they need through the role of leadership, such as playing the role of monitor or coach (Chebon et al., 2019; Bin Bakr and Alfayez, 2021). Therefore, employees’ POS has been viewed to be primarily associated with their managers (Lipponen et al., 2018). The above functions of a leader make employees feel being strongly supported by management, a way of showing them that their organization cares about them. In this case, the employees will perceive support from their organization (Kurtessis et al., 2017). In fact, some recent studies have shown that transformational leadership facilitates employees’ perception of support from the organization. For example, Asgari et al. (2020) studied college students and proposed that transformational leadership has a positive effect on employees’ POS. Hermawati et al. (2021) studied perceived organization support and demonstrated that transformational leadership has an effect on the followers’ POS. Dinc et al. (2022) examined the effect of transformational leadership on employees’ creativity and found that transformational leadership plays a critical role in employees’ POS. In multi-level organization theory models, group-level variables affect individual-level outcome variables cross-levels (Raudenbush and Bryk, 2002). In other words, transformational leadership at the group level not only affects organizational climate, but also affects individual POS and volunteer participation motivation cross-levels as well. Based on this, research on leadership must pay attention to the correlation between variables at different levels. The above theoretical discussion or research shows that transformational leadership can affect the outcome variables of employees’ POS and volunteer participation motivation, and can influence the context variables of the organization (Elgamal, 2004). Therefore, through multi-level research, employees’ perceptions of leaders can be aggregated to the group level, and their relationship with POS and volunteer participation motivation can be tested.

As a result, the fourth hypothesis was proposed:

Transformational leadership makes employees’ job more meaningful, creates high-quality teamwork, and give employees a feeling of satisfaction. Transformational leadership has a huge effect on maintaining the environment driving volunteering (Althnayan et al., 2022). Individuals who see their job as meaningful or have an autonomous motivation are more likely to feel satisfied with their job and to help other people (Purvanova et al., 2006). Volunteering is a way to show one’s altruistic value, to establish a strong relationship, to improve one’s self-esteem, to shift one’s attention away from personal issues, to learn and acquire new knowledge and skills about the world, and to improve career prospects (Afkhami et al., 2019). Transformational leadership affects employees’ volunteer participation motivation by satisfying their needs for interpersonal relationship and building good relationships (Chan, 2020). Moreover, transformational leaders link work to employees’ values through their charismatic leadership style, boost employees’ confidence, and facilitate team identification and cohesion, which together elicit employees’ volunteer participation motivation (Shofiyuddin et al., 2021).

As a result, the fifth hypothesis was proposed:

Employees constitute an important part of every organization, and form a general perception of the organization based on their work in the organization and their experience with the organization’s internal environment such as organization management, organizational culture, and the content and place of work. The behavior of employees is affected by this general perception (Licciardello et al., 2013). A positive organizational climate enhances employees’ job performance, creates a positive employee relationship, and boosts their job satisfaction. Therefore, a positive work environment through good interpersonal relationships and a healthy organizational climate can help motivate people to volunteer (Lee and Brudney, 2015). Suresh and Venkatammal (2010) believed that organizational climate is a collection of attitudes that an organization influences individuals and groups, like rewards and interpersonal relationships. Gholami et al. (2015) viewed organizational climate as employees’ perceptions of organizational characteristics, such as leadership styles, decision-making processes, and work norms. Furthermore, according to Sudibjo and Nasution (2020), and Suprapti et al. (2020), the benefits of the work environment are to create of passion for work, and improve work performance. Therefore, a positive work environment can create a good organizational climate, promote the sharing of the organization’s values, beliefs, and behaviors, and then induce employees to exhibit more behaviors that are beneficial to the organization (Novitasari and Iskandar, 2022).

Many studies have found that fairness (Salam, 2020), a sense of self efficacy (Zhou and Qian, 2021), collective efficacy (Strydom, 2021), and group cohesion (Schmidthuber and Hilgers, 2019) are the antecedents of employees’ ex-role behavior. Engagement in volunteer services or activities gives people an opportunity to show their altruistic values (Clary et al., 1998) and trigger their ex-role behavior. For example, Azizaha et al. (2020) and Desky et al. (2020) pointed out that the motive of an individual, group cohesion and employees’ attitude are closely related to triggering employees’ OCB. Therefore, establishing a good organizational climate and as such a strong group cohesion will further encourage employees’ OCB (Schmidthuber and Hilgers, 2019). This study defines organizational climate as a group-level variable. Since this study uses cross-level analysis, hypotheses about the group-level effect on individual-level dependent variables can be tested (Cho and Kao, 2022). In summary, organizational climate can affect volunteer participation motivation and organizational outcomes of OCB.

Consequently, the sixth and seventh hypotheses were proposed:

Perceived organizational support is the development of an organization’s beliefs in its employees and when employees recognize that their contribution and well-being are highly valued by the organization, employees will feel obligated to help their organization achieve its goals. Therefore, it is very important for the organization to build this belief among employees. This questionnaire was modified from the one used by Eisenberger et al. (1997). There were 15 questions after the modification, and the objective was to measure the elements of POS. One of the questions was “Does the organization value my contributions?” Another question in the questionnaire was “Does the organization actively provide administrative or training resources?”

Volunteer participation motivation refers to the motivation of employees to voluntarily participate in activities or affairs outside the organization. It is part of social motivation and has altruism, which makes volunteers motivated to care for others voluntarily. This study adopted and modified the six aspects of volunteer participation motivation of Wan et al. (2007). In total, there were 32 questions in the revised questionnaire, and they were used to assess the six elements of volunteer participation motivation. There were ten questions for enriching life and learning motivation, the first element. One of the questions was “does volunteering enrich my life?” There were five questions for the element “social responsibility,” and one of the questions was “can I make contributions to society by volunteering?” There were five questions for self-development motivation, and one of the questions was “does volunteering provide self-development opportunities?” There were four questions for the element “motivation for achievement,” and one of the questions was “can I serve the public by volunteering?” For the element “institutional characteristics,” there were four questions, and one of the questions was “By volunteering can I obtain printed materials from that organization or can I participate in activities held by the organization for free or with a discount?” The last element was “will realization motivation,” and there were four questions, one of which was “can I volunteer to reach my full potential?”

Organizational citizenship behavior is considered as an unconditional work behavior of employees. Although this behavior is not clearly stipulated in the job description, employees still voluntarily engage in it, and the display of this behavior can effectively promote the performance of the organization. This questionnaire was developed based on Farh et al. (2004) and Lin (2007). Three OCB dimensions were included in this inventory: in-role behavior, organizational charitable behavior, and interpersonal altruistic behavior. Each dimension contained two sub-dimensions. For in-role behavior, the sub-dimensions were identification with the company and taking initiative. For organizational charitable behavior, the sub-dimensions were diligence, prudence and protecting the company’s resources. For interpersonal altruistic behavior, the sub-dimensions were interpersonal harmony and assisting one’s colleagues. When conducting the survey, both the employees and their managers were asked to fill out the questionnaires in order to eliminate the possibility of common method variance. By doing so, the researcher could assess if there is any discrepancy between the actual perception of the employees and the employees’ behavioral evaluation conducted by their managers. Both questionnaires contained six questions on identification with the company. One question from that part was “should I (the subordinate) try my best to protect the company’s image and actively participate in all related activities?” There were three questions under taking initiative and one of them was “If it is required for business, should I (the subordinate) go to the office earlier to do my work?” For diligence and prudence, there were 11 questions. One of the questions was “should I (the subordinate) put effort into self-enrichment in order to improve the quality of my work?” For saving the company’s resources, there were three questions. One of the questions was “should I (the subordinate) try to save organizational resources such as water, electricity, and office stationery?” For interpersonal harmony, there were five questions. One of the questions was “should I (the subordinate) actively communicate and coordinate with my colleagues?” There were three questions under assisting colleagues. One of the questions was “should I (the subordinate) be happy to assist my colleagues and to solve problems encountered at work?” Altogether, there were 31 questions and six sub-dimensions.

Transformational leadership is a process of organizational change, based on members’ consensus on organizational commitment, it can combine the common needs and aspirations of organizational members, share a group-interest-oriented vision with those around it, and create a loyal working climate. To evaluate transformational leadership, this study adopted the multifactor leadership questionnaire (MLQ) developed by Bass and Avolio (1997). MLQ covers four dimensions: six questions on idealized influence, five questions on inspirational motivation, four questions on intellectual stimulation, and four questions on individualized consideration. For idealized influence, it was used to measure the role of the leader in his or her job position. One of the questions from the idealized influence dimension is “would my supervisor put group interest above his own interest?” One of the questions from the inspirational motivation dimension was “does my supervisor have a positive view of the future?” For the intellectual stimulation dimension, one of the questions was “Why does my supervisor ask me to see a problem from various aspects?” Last, for the individualized consideration dimension, one of the questions was “does my supervisor help me realize my potentials?”

Organizational climate is an evaluable feature of the work environment, which is the direct or indirect perception of an individual’s life and job in the work environment, and it is the common understanding among members of the same organization. This study revised the organizational climate questionnaire used in Kao (2017), which is based on the Litwin and Stringer Organizational Climate Questionnaire (LSOCQ) (Litwin and Stringer, 1974). The organizational climate questionnaire used here has four dimensions and 18 questions in total: six questions on management style, four questions on interpersonal relationship, four questions on structural climate, and four questions on climate responsibility. The organizational climate questionnaire was used to evaluate management styles (e.g., the job promotion system), interpersonal relationships (e.g., a friendly climate), structures (e.g., a very high performance standard), and responsibility (e.g., individuals do not need to take any responsibility).

According to studies such as Farh et al. (2004), Kao (2017), and Cho and Kao (2022), this study included age, education, seniority as the control variables and examined their relationships with other study variables.

This study tested the relationship between the control variables, the individual-level variables, and the group-level variables by Hierarchical Routing Architecture (HRA). Model 1 in Table 3 shows that group-level control variables had no significant effect on organizational climate. Model 2 shows that transformational leadership had a significant effect on organizational climate (β = 0.307, p < 0.001), and after adjustment, it had a R² of 0.287. The F-value was statistically significant (p < 0.001). Models 3 and 5 show that individual-level control variables had no significant effect on either volunteer participation motivation or OCB. In addition, Model 4 shows that POS had a significantly positive effect on volunteer participation motivation (β = 0.319, p < 0.001). The adjusted R² was 0.273, and the F-value was statistically significant (p < 0.001). It can be seen from Model 7 that volunteer participation motivation had a moderating effect on the relationship between POS and OCB (β = 0.335, p < 0.05). Therefore, H1 to H3 cannot be rejected. In other words, POS had a significantly positive effect on volunteer participation motivation, while volunteer participation motivation had a moderating effect on the relationship between POS and OCB. Transformational leadership had a significantly positive effect on organizational climate.

This study used the hierarchical linear model (HLM) to test the cross-level effect of group-level variables.