Direct and indirect effects of servant and ethical leadership styles on employee creativity: mediating role of organizational citizenship behavior

Abstract

Purpose

This research mainly aims to test the impact of two leadership styles (ethical and servant leadership) on employee creativity; and to determine whether organizational citizenship behavior (OCB) mediates the relationships between them.

Design/methodology/approach

The paper relied on a quantitative research approach with a sample of 213 staff from public universities in the United Arab Emirates. In this paper, the partial least square approach (PLS-SEM) was employed in order to verify the proposed hypotheses.

Findings

The outcomes confirmed that OCB has a positive impact on employee creativity. Additionally, the findings indicated that ethical leadership positively affected OCB and employee creativity. It was also confirmed that servant leadership has a significant positive impact on OCB and employee creativity. Finally, the findings revealed that OCB fully mediates the linkages among servant and ethical leadership and employee creativity.

Originality/value

This paper acknowledges the existing gaps in the prior literature, and enables us to understand clearly about the significance of ethical as well as servant leadership in affecting employee creativity via OCB as a mediator.

Citation

Hanaysha, J.R., Kumar, V.V.A., In'airat, M. and Paramaiah, C. (2022), "Direct and indirect effects of servant and ethical leadership styles on employee creativity: mediating role of organizational citizenship behavior", Arab Gulf Journal of Scientific Research, Vol. 40 No. 1, pp. 79-98. https://doi.org/10.1108/AGJSR-04-2022-0033

1. Introduction

Employee creativity is one of the foremost researched topics which attracted the attentions of several academic scholars and policy makers. It was defined in the prior literature as the ability to generate new or novel ideas that enable an organization to identify promising business opportunities, solve existing problems and achieve desired business objectives (Cohen-Meitar, Carmeli, & Waldman, 2009). Employee creativity has been regarded by several researchers as a main driver of competitive advantage for business organizations (Chughtai, 2016; Lee, Kim, Lee, & Moon, 2019). Maintaining or improving organizational effectiveness in today's highly changing and competitive environment calls for ensuring creative behavior among employee at workplace (Parke & Seo, 2017). A number of scholars have been concerned about identifying the predictors of employee creativity in organizations (Ma, & Jiang, 2018; Tse, To, & Chiu, 2018). A leader's behavior has been acknowledged in the previous studies as an important factor for shaping organizational environment as the supervision style of the leader exerts a noteworthy impact on employees' attitudes and behaviors either directly or indirectly (Zhou & George, 2003). Organizational leadership has also been perceived and viewed by several business stakeholders as an important driver of business success in today's dynamic markets (Hanaysha, 2020; Tse et al., 2018).

Prior studies reported that employee creativity can be influenced by a leader's supportive and ethical behavior (Li, Lu, & Eliason, 2022; Feng, Zhang, Liu, Zhang, & Han, 2018; Javed, Rawwas, Khandai, Shahid, & Tayyeb, 2018; Chughtai, 2016). Ethical leadership emphasizes on communicating, promoting and reinforcing the ethical conducts of subordinates and ultimately cultivating favorable attitudes among them, for instance innovative work performance (Bedi, Alpaslan, & Green, 2016) and organizational citizenship behavior (Seth, Sethi, Yadav, & Malik, 2022; Shareef & Atan, 2018). Accordingly, organizational leaders have to be the role models in fostering ethical behavior at the workplace in order to nurture the creativity among their employees (Ma, Cheng, Ribbens, & Zhou, 2013). Chughtai (2016) indicated that ethical leaders can create a supportive environment through building effective communication channels that ultimately lead to employee creativity. However, different mediated mechanisms may exist to reinforce the linkages among ethical leadership and individual creativity. In prior research, OCB was examined as a mediator between among different styles of leadership and individual performance. Sugianingrat et al. (2019) confirmed that OCB acts as a key mediator between ethical leadership and worker performance. Moreover, Jiang, Zhao, and Ni (2017) testified that OCB could mediate the correlation between transformational leadership style and the sustainable performance of employees. However, in the current literature, there is a limited empirical evidence to prove whether OCB plays an intervening role in the linkage among the ethical leadership style and employees' creativity. Thus, in order to address the existing gaps, we used OCB as a mediator between both constructs.

Furthermore, the substantial influence and theoretical significance of servant leadership in determining employee creativity has been established in the literature (Xu, Li, Sun, Cheng, & Xu, 2022; Yang, Gu, & Liu, 2019; Jaiswal & Dhar, 2017; Yoshida, Sendjaya, Hirst, & Cooper, 2014). Servant leadership emphasizes on the role of leaders in assisting their subordinates and attempting to support them in achieving their full potentials (Liden et al., 2015). It tends to be associated positively with an employee's creative behavior (Yang et al., 2019). However, contemporary research reported dissimilar findings (Vessey, Barrett, Mumford, Johnson, & Litwiller, 2014). While the above prior researches have shown the strong linkages between servant leadership and the creativity of employees, other scholars found an insignificant link between both constructs (Newman, Schwarz, Cooper, & Sendjaya, 2017). These inconsistent results attract the attention among researchers to further examine the actual relationship between both variables. Hence, it is important to determine via which approaches and through which boundary settings servant leadership is interrelated with the creativity of employees. OCB as a psychological behavior may play a key role as a mediator in the association among leadership style and employee behavior. While OCB may have a positive influence on employee creativity, there has been a scarce empirical research which examined if OCB may mediate the relationship among both of servant and ethical leadership and worker creativity (Newman et al., 2017). The current research focuses on making a significant contribution to empirical literature and supporting theories through the analysis of the effect of servant and ethical leadership styles on employee creativity in the higher education sector in United Arab Emirates. This study also intends to provide a key contribution to the empirical literature by testing role of OCB as a mediating variable between these types of leadership and the creativity of employees. The subsequent section shows the literature review about the variables of the present study. After that, the methodology and findings are presented.

2. Literature review

2.1 Employee creativity

Individual creativity, according to Amabile and Pratt (2016) can be conceptualized as the ability to develop novel and beneficial ideas. Employees can demonstrate creativity by generating new information, advancing technology, or improving processes that lead to inventions (Xu et al., 2022; Parr, Hunter, & Ligon, 2013). Certain scholars have given “process” oriented descriptions of creativity, concentrating on the steps of individual creative creation, despite the fact that most academics have observed that the usual approach in the literature presupposes an “outcome”-oriented definition of creativity (Amabile, 1995; Sternberg & Lubart, 1991). Creativity was also described as a worker's innovative thinking, know-how, and talents built on their familiarity and credentials. The creativity of employees alludes to the creation, advancement and execution of novel and helpful thoughts regarding work practices, organizational services, or strategies (Chae, Lee, Hwang, & Park, 2015; Zhou, Oldham, Chuang, & Hsu, 2022). According to Kim and Shin (2019), organizational support, challenges and workload pressure are all key elements that demand the application of creative talent and employees' creativity. Therefore, creativity is created by people in a complex social system that focuses on developing valued and novel products, services and new concepts (Woodman, Sawyer, & Griffin, 1993). In general, the most common definition of creativity is the act of generating new ideas, inventions, promotions, valuable products, services and useful concepts.

It was reported in the literature that creativity occurs through the generation of new thoughts to increase performance, efficiency and efficacy (Gong, Huang, & Farh, 2009). Worker creativity demands a great level of mental endeavor; as a result, employees must be stimulated to demonstrate strong performance in order to create breakthroughs. Employee creativity serves as a raw ingredient for an organization's growth (Lukes & Stephan, 2017). It is a component of innovation that involves the progression of creative ideas into action (Oldham & Cummings, 1996). Undoubtedly, firms that promote employee creativity to transform ideas into innovative goods and services have a competitive advantage in the marketplace (Kremer, Villamor, & Aguinis, 2019). In addition to that, innovative personnel can exchange helpful and novel ideas to make essential product and service changes (Shalley, Gilson, & Blum, 2000). Employee creativity has nowadays become a differential competitive advantage that is required for the growth of an organization (Lukes & Stephan, 2017). Thus, corporate leaders should encourage creative and inventive work and offer support for employee innovation at workplace (Khalili, 2013).

2.2 Organizational citizenship behavior (OCB)

OCB has received significant emphasis in the fields of organizational behavior and organizational psychology among scholars and human resource (HR) practitioners. OCB was described in the literature as “a voluntary individual behavior that promotes overall organizational performance but is not included in the organization's formal incentive system” (Organ & Podsakoff, 2006). Certain scholars also referred OCB to workers' casual and willful endeavors toward supporting their peers and organizational development (Organ, 1988). Moreover, Farh, Zhong, and Organ (2004) defined OCB as the acts taken by workers which are not explicitly stated in their prescribed job descriptions. That is, OCB places a premium on employee contributions that go above and beyond what is expected from them; in other words, at work, extra-role behavior contributes to the company's achievement (Posdakoff et al., 2009). These definitions are similar to that of Organ (1988) who conceptualized OCB as a voluntary work behavior which is not reflected in the prescribed system of reward, and that generally reinforces the smooth operation of the corporation. In addition, he identified five major components that directly contribute to OCB: benevolence, meticulousness, sportsmanship, politeness and civic virtue.

Interpersonal assistance that is demonstrated via OCB can explain a significant variance in individual output and performance quality, efficiency and effectiveness (Organ & Podsakoff, 2006). OCB facilitates social interaction and minimizes social friction. In the prior literature, OCB has been acknowledged as a beneficial practice to organizations (Gilmore, Hu, Wei, Tetrick, & Zaccaro, 2013). According to Zhang and Bartol (2010), OCB assists workers in offering ground-breaking ideas to coworkers; however, Vessey et al. (2014) believe that OCB assists workers in making creative recommendations to coworkers. As they work their way through the organization's social structure, citizenship behaviors may also operate as a catalyst for innovation, influencing others' behavior in a favorable manner conducive to spontaneous acts of invention, both directly and covertly (Turnipseed, 2002). According to Podsakoff, Whiting, Podsakoff, and Blume (2009), OCB can improve organizational performance by increasing the productivity of coworkers and supervisors, promoting cooperation across working groups, and allowing the company to respond to sustainable changes. Participating in OCB activities improves employees' strengths, which leads to the growth of employees' assets, resulting in better well-being (Lam, Wan, & Roussin, 2016). Earlier findings also confirmed that OCB is positively associated with employee creativity (Podsakoff et al., 2009; Yoshida et al., 2014; Lam et al., 2016). Based on the mentioned literature, we propose the first hypothesis:

H1.

OCB has a positive impact on employee creativity.

2.3 Servant leadership

Servant leadership is distinguished by the provision of direction, encouragement, growth of others, the demonstration of humility, authenticity, extending help and custodianship (Van Dierendonck, 2011). According to previous studies, employees who feel empowered exhibit confidence and may have a direct impact on their organizations (Russell, 2016). Servant leaders who genuinely care about their subordinates can be inspiring role models for them (Chon & Zoltan, 2019; Liden, Wayne, Liao, & Meuser, 2014). According to Hu and Liden (2011), effective servant leadership can promote real equity culture, service commitment and serving society, which in turn influence team effectiveness and performance. In fact, servant leaders are thought to furnish employees with help (helping subordinates grow and succeed dimension) and freedoms to acquire new abilities (assisting subordinates with career growth), self-development and effectively partake in dynamic and critical thinking (empowering dimension) (Liden et al., 2014). Earlier studies documented that servant leaders have a tendency to be concerned about the prosperity of employees and demonstrate optimistic psychological state among them, and this as a result leads to greater appreciation and expanded trust (Kelloway, Turner, Barling, & Loughlin, 2012). Individual outcomes, for instance employee behavior, work engagement, OCB, career development and performance have all been linked to servant leadership in the empirical research (Walumbwa, Hartnell, & Oke, 2010).

Servant leadership style is grounded in the social exchange theory, which focuses mainly on the well-being and support of subordinates (Greenleaf, 1998). Individual conduct at work, according to the theory comprises a chain of contacts that establish responsibilities for employee to behave in a certain manner (Blau, 1964). It claims that perks and favors bestowed on employees by their bosses lead to the formation of favorable exchange interactions, which ultimately necessitate subordinates to reciprocate in similar means (Settoon, Bennett, & Liden, 1996). In general, the social exchange theory enables us to comprehend the reciprocal relationships that exist between organizations' leaders and their staff (Jaiswal & Dhar, 2017). According to this theory, subordinate usually respond in the same way that their leaders communicates with them. That is, if a leader treats his or her subordinates fairly, helps them when they are in need, shows care and supports them, the followers will respond positively (Shareef & Atan, 2018). Consequently, they may be more motivated to take on additional responsibilities and engage in creative behavior (Chen & Kanfer, 2006). Previous studies has shown support for these claims by demonstrating a strong linkage among servant leadership and creative conduct (e.g. Hammond, Neff, Farr, Schwall, & Zhao, 2011; Volmer, Spurk, & Niessen, 2012).

Servant leadership has been discussed in terms of its theoretical relevance and its broad influence on employee and group innovation (Jaiswal & Dhar, 2017; Yang et al., 2019). Similar to ethical leadership, servant leadership moves followers beyond immediate self-interest by idealistic influence. Many researchers have demonstrated the role of servant leadership style in determining employee creativity (Wang, Kang, & Choi, 2022; Yoshida et al., 2014). Liden et al. (2014) found that servant leadership is allied with a resilient service philosophy and employee identity, which leads to enhanced employee creativity. Overall, academics have paid enormous attentions to the potential link among servant leadership style and employee creativity, but it has not been agreed among them regarding the nature of this association (Newman et al., 2017). According to Yang et al. (2019), servant leadership is positively linked to service philosophy and employee distinguishing proof, which leads to higher employee creativity. To better understand the statistical linkages among servant leadership and worker creativity, scholars have recommended to pay an attention to the intervening elements.

Servant leaders are expected to produce a service culture in their organizations by ensuring that they have the tools and support to generate high levels of attitudes and behaviors in order to maintain the service cycle (Russell, 2016). Leader who exhibit empathy, care toward their followers, act in their best interests (Van Dierendonck, 2011), minimize their load and motivate them to uncover serving qualities in OCBs, can foster positive behaviors among their followers. Employees will notice that service culture necessitates behaviors that go beyond formal requirements in business environment, which will probably lead to a greater OCB inside their workgroup (Walumbwa et al., 2010). By serving them or changing their surroundings, servant leaders can reinforce workers' motivation, capacity, or the chance to exhibit OCB (Qiu & Dooley, 2022; Greenleaf, 1998). Furthermore, OCB can function as a mechanism that connects leadership behaviors and employee creativity, because OCB tends to be fostered through servant leadership, which leads to knowledge exchange among employees. Further evidence was documented in prior researches which showed that servant leadership positively affects OCB (Gnankob, Ansong, & Issau, 2022; Elche, Ruiz-Palomino, & Linuesa-Langreo, 2020; Tuan, 2017) and in turn, OCB leads to greater employee creativity (Xerri & Brunetto, 2013). According to the above arguments, the subsequent hypotheses are projected:

H2.

Servant leadership has a positive impact on OCB.

H3.

Servant leadership has a positive impact on employee creativity.

H4.

OCB mediates the relationship between servant leadership and employee creativity.

2.4 Ethical leadership

Given the prevalence of ethical scandals in most of the organizations, the need for an ethical leadership style has become vital. Brown, Treviño, and Harrison (2005) expressed ethical leadership as “the demonstration of normatively acceptable behavior via close to personal activities and interpersonal relationships, and the advancement of such conduct to followers through two-way communication, support and decision-making.” As such, this definition features three fundamental qualities of an effective ethical leader: the person who (1) strives to put what he or she talks into practice, (2) has faith in justice and (3) conveys significant information. The role of ethical leadership in fostering employee creativity has received substantial attention from researchers (Javed, Khan, Bashir, & Arjoon, 2017). According to several studies, leaders' initiatives and ethical behavior have a major influence on staff creativity. Employees who have more autonomy and clear direction from their leaders are likely to foster creative behavior at workplace (Jiang et al., 2017).

Social exchange theory postulates that an ethical leader's behaviors institutionalize ethical conduct and discourage misbehavior among subordinates, resulting in the formation of shared ethical standards and attitudes (Arshad, Abid, & Torres, 2021; Bedi et al., 2016; Chen & Chiu, 2009). When employees are inspired by a leader who displays high morals and ethical behavior, they are more likely to identify, replicate and absorb such habits (Bedi et al., 2016; Hammond et al., 2011; Brown, 2007). Furthermore, Cropanzano and Mitchell (2005) reported that when subordinates feel that they are treated ethically and responsibly, as defined by social exchange processes, they will reciprocate their leaders' attitudes and actions and promote a consistent ethical climate throughout the firm. Furthermore, ethical organizational practices encourage ethical leadership by creating morally accepted behaviors in followers and increasing organizational success.

In accordance with social exchange theory, the followers' creativity can be improved through their daily interactions with their leaders (Hammond et al., 2011). Several scholars paid depth attention to ethical leadership instead of entirely looking from a moral standpoint, in accordance with the idea that individuals who are committed to ethical practices tend to work more than those who are driven merely by economic or social considerations. Employees are likely to feel motivated for assisting others in generating novel ideas when they feel their work is appreciated and meaningful (Kalshoven, Den Hartog, & De Hoogh, 2011). Employees tend to improve their learning and proactive behaviors when they have ethical leaders, and as a result, they may become more innovative (Dhar, 2016; Pandey, Gupta, & Gupta, 2019). The above information help us understand how people respond to ethical and servant leadership styles.

Ethical leadership has also been viewed as a key determinant of OCB in the prior literature (Tuan & Ngan, 2021). OCB is a key element that could strengthen or mediate the relation between ethical leadership and creativity. By providing appropriate knowledge, ethical leaders enhance the value of their workers' efforts. Employees, in turn, exhibit greater commitment to their organizations and departmental goals by contributing through novel ideas and making decisions which could impact the company's performance and profitability (Chen & Hou, 2016). The ethical leadership work atmosphere encourages workers to exchange their thoughts, be creative and vigorously participate in the decision-making process (Chen & Hou, 2016). Ethical leaders who keep lines of open communication to create a stable atmosphere encourages employee creativity (Chughtai, 2016).

Furthermore, previous researchers analyzed the intervening role of OCB among leadership style and employee performance. In the study of Sugianingrat et al. (2019), it was found that OCB intercedes the connection among ethical leadership and employee outcomes. Jiang et al. (2017) also revealed that OCB could mediate the association between certain leadership types and employee performance. Nonetheless, in the current literature, there is limited evidence to show how OCB could mediate the relationship among ethical leadership style and employee creativity. Through the growth of trust, honesty, compassion, virtuousness and justice within their interactions, ethical leaders appreciate and tolerate their workers' differing beliefs and ideas. They shape and influence business culture, promote employee autonomy and appreciate their ideas, all of which stimulate employee creativity (Qing, Asif, Hussain, & Jameel, 2020; Rego, Sousa, Marques, & Cunha, 2012). Moreover, some researchers found that OCB has positive association with employee creativity (Öğretmenoğlu et al., 2021; Xerri & Brunetto, 2013). Thus, the subsequent hypotheses are proposed:

H5.

Ethical leadership has a positive impact on employee creativity.

H6.

Ethical leadership has positive impact on OCB.

H7.

OCB mediates the relationship between ethical leadership and employee creativity.

3. Methodology

The primary data for the current research was obtained from full-time employees at public universities in the United Arab Emirates through a structured survey. In details, administrative and academic staff in public universities were approached for participation in data collection. Due to the lockdowns as a result of COVID 19, the online survey was the most appropriate method for data collection. Accordingly, an online link for the designed survey was sent to the participants at different times over the day and the data was collected within five months (June – October, 2021). This process was adopted to avoid any probable issue of the common bias method. During data collection, convenience sampling method was used for obtain the desired number of responses. This sampling methodology was adopted in several previous studies which collected the data for these variables similar respondents. In the first section of the survey, the respondents answered about their demographic particulars, which comprised of gender, age, qualification and work experience. Then, in the second section, servant and ethical leadership styles, OCB and employee creativity were measured based on a set of questions. In general, 213 staff participated in the survey and answered all of the questions. Academic staff represented 83.6% of total response, while administrative staff accounted for 16.4%. About 58.2% (124) of the participants are represented by males, while females accounted for 41.8% (89). Additionally, the majority (63.4%) of the participants were in the age group of 36 to 45 years, and 54.5% of them have been working in their institutions for less than five years.

All of the items in the designed survey were measured in accordance with the five-point Likert's scale that fall in the range of (1) strongly disagree to strongly agree (5). First, four items were employed to measure employee creativity based on the scale developed by Yang, Liu, and Gu (2017). The adapted items were measured via self-rating method consistent with prior research (Henker, Sonnentag, & Unger, 2015). An example of the items for employee creativity is “I come up with creative solutions to problems”. The Cronbach's alpha value for these items was 0.82. OCB was also assessed through self-report on a four item's scale which was developed by Cardona, Lawrence, and Bentler (2004). An example of the selected items includes “I do more than the job I am paid to do”. The value of Cronbach's alpha was registered at 0.79. Furthermore, servant leadership scale consisted of 14 items being adapted from Ehrhart (2004). An example of the selected items includes “My supervisor does what she or he promises to do”. The value of Cronbach's alpha for these items was 0.80. Finally, a ten-items scale was adapted from Brown et al. (2005) to obtain employees' perceptions toward ethical leadership. An example of the selected items includes “My supervisor makes fair and balanced decisions”. These items had acceptable Cronbach's alpha value of 0.86.

4. Analysis of results

This study used the test of Harman's one-factor to ensure a minimal effect of common method bias that might be caused as a result of the common method employed for collecting the data. The maximum value of the variance explained for the four constructs was 31.08%, which reveals that the results do not have any common method bias or issue (Podsakoff & Organ, 1986). Furthermore, a test of the common latent factor (CLF) was done for testing the common variance among all of the hypothesized variables in accordance with the suggestions of Podsakoff, MacKenzie, Lee, and Podsakoff (2003). As the difference among the model's standardized regression weights including CLF and without including it were lower than 0.200, it can be concluded that the current data does not have any issue from common variance.

After checking the common method bias, the descriptive statistics of variables (means and standard deviation) and correlations were analyzed. As displayed in Table 1, OCB has a positive correction with employee creativity (r = 0.605, p < 0.01). It also shows that servant leadership has a positive correlation with OCB (r = 0.472, p < 0.01) and employee creativity (r = 0.549, p < 0.01). Furthermore, ethical leadership has a positive correlation with OCB (r = 0.598, p < 0.01) and employee creativity (r = 0.514, p < 0.01). The analysis also showed that servant leadership and ethical leadership are positively associated (r = 0.411, p < 0.01). In total, these findings provide an initial support for the main hypotheses. The values of mean statistics for the variables were also registered as follows: servant leadership (3.96), ethical leadership (3.93), OCB (4.02) and employee creativity (3.87). Finally, the standard deviation for all constructs ranged from 0.76 to 0.98.

Before testing the hypotheses, the validity and reliability of the measures were evaluated based on the measurement model. To establish convergent validity across the measures, the factor loadings were calculated. As displayed in Table 2 and Figure 1, the factor loadings of the residual items in the estimated measurement model are greater than 0.6. Consistent with the suggestions of Dash and Paul (2021), the factor loadings registered at 0.6 or above are regarded as significant, therefore the loadings contribute significantly to each construct. Additionally, the average variance extracted (AVE) was evaluated and the results indicated that the values for all constructs exceeded 0.5 (see Table 2). Hair, Ringle, and Sarstedt (2011) reported that the minimum tolerable value for AVE is 0.5. Therefore, the AVE values generated through the measurement model are acceptable. To estimate reliability across the items of each construct, the PLS-SEM was used. Based on the analysis of measurement model, it was found that Cronbach's Alpha surpassed the minimum acceptable value of 0.70 as advocated by Hair, Black, Babin, Anderson, and Tatham (2010). The result provides an indication of high internal consistency among the selected constructs. Finally, the estimates of composite reliability surpassed the lowest tolerable range 0.70. Based on these results, it can be said that the scales did not indicate any issue with regards to convergent validity. This is based on the suggestions of Hair et al. (2011) who stated that the minimum tolerable value for composite reliability is 0.5.

4.1 Hypothesis testing

After achieving the assumptions of reliability and validity via the measurement model using PLS-SEM, the structural model was verified. Through the structural model, it was possible to test all of projected hypotheses. The findings presented in Table 3 reveal that OCB's effect on employee creativity is positive and significant (β = 0.387, t-value = 3.361, p < 0.05), hence, H1 is supported. The statistical analysis also confirmed that servant leadership positively affects employee creativity (β = 0.307, t-value = 1.974, p < 0.05) and OCB (β = 0.516, t-value = 2.889, p < 0.05); thus, H2 and H3 are accepted. Additionally, the findings exhibited that ethical leadership has a positive effect on employee creativity (β = 0.275, t-value = 1.990, p < 0.05) and OCB (β = 0.380, t-value = 2.099, p < 0.05); thus, H5 and H6 are accepted. Overall, servant and ethical leadership explain 77.7% of variance in OCB. In total, servant leadership, ethical leadership and OCB explain 86.7% of variance in employee creativity.

To verify if OCB really has a mediator between the two types of leadership (servant and ethical leadership) and the creativity of employees, the study relied on the suggestions of Preacher and Hayes (2008). First, the indirect effect concerning the effects of leadership styles on creativity should be calculated. According to their suggestions, if it is significant and positive, then the first condition for mediation test is achieved. Next, the values of both lower bound as well as upper bound must be calculated. If zero value does not come between the lower bound and upper bound of the 95% confidence intervals (CIs), then it can be considered that the indirect effect is significant and the mediating effect is confirmed.

As displayed in Table 4, the total effect of servant and ethical leadership on employee creativity significant. Furthermore, Table 5 shows that the indirect effect of servant leadership on employee creativity (β = 0.472, p < 0.05) is significant. The value of lower bound is 0.160, while the upper bound's value is 0.748; therefore, zero does not fall in the range between these values. Based on this result, it can be confirmed that OCB fully mediates the association between servant leadership and employee creativity; consequently, H4 is accepted. Lastly, the outcomes showed that there is a significant positive indirect effect of ethical leadership on employee creativity through OCB (β = 0.328, p < 0.05). In the below table, it can also be seen that the lower bound's value is 0.005, whereas the value of upper bound is 0.652. This means that OCB fully mediates the relationship among ethical leadership type and individual creativity is supported; hence, H7 is confirmed.

5. Discussion and conclusion

In this research, the key purpose was to identify the impact of OCB on employee creativity. Our findings supported that OCB plays a noteworthy role in determining employee creativity. Podsakoff et al. (2009) also confirmed that OCB is positively associated with firm effectiveness, and this may mean that OCB is vital for enhancing workers' creativity. Committed and loyal employees tend to have better performance and add greater values to the organization. Moreover, employees who reveal positive OCB tend to be self-motivated and display a creative behavior as an indication about their sense of belongingness (Xerri & Brunetto, 2013). Van Dyne and LePine (1998) also added that employees provide creative suggestions to their peers through the help of OCB. Therefore, it can be stated that an employee who demonstrates high commitment and loyalty toward his or her firm tend to feel motivated to come up with creative ideas for resolving workplace issues (Van Dick, Wagner, Stellmacher, & Christ, 2004). However, by looking at the published literature, it can be seen that there are insufficient studies which tested the empirical relationship between OCB and employee creativity. This paper, consequently, suggests that an organizational climate in which the workforces continually assist each another and share their knowledge should be associated positively with creativity.

The research further aimed to determine whether servant leadership style exerts any effect on employee creativity and if OCB could act as a key mediator among both constructs. The findings provided support for the significant linkages among servant leadership style and employee creativity, as well as servant leadership and the OCB. It also confirmed that OCB acts as a significant mediator among servant leadership and individual creativity. The finding is in agreement with those of previous research which confirmed that servant leadership was associated positively with employee creativity (Nguyen, Nguyen, Vo, & Tuan, 2022; Yang et al., 2019; Jaiswal & Dhar, 2017). Certain scholars (Neubert, Hunter, & Tolentino, 2016; Chan & Mak, 2014) outlined that servant leaders have a tendency to encourage and provide the needed assistance for their employees through empowerment, prioritizing on their needs' fulfillment and enabling them to reach their full potential. The authors added that servant leaders center their emphasis on the engagement and intrinsic motivation of their staff in creative behaviors. Prior literature (Ma & Jiang, 2018; Yoshida et al., 2014) also indicated that servant leadership style was positively linked with employee creativity. Using the social exchange theory, this paper also aimed to identify the mediating effect of OCB among servant leadership style and employee creativity. It was found that OCB plays an important mediating role between both constructs. This result showed empirical support for the suggestions of Liden et al. (2014) who declared that mediating variables should be existent in the relationship among servant leadership style and employee behavior.

The statistical findings also displayed that servant leadership style positively affect OCB and this is in line with prior literature (Aboramadan, Hamid, Kundi, & El Hamalawi, 2022; Elche et al., 2020; Tuan, 2017; Newman et al., 2015). OCB is a discretionary behavior that is not likely to be realized through the formal system of reward. Such behavior tends to be developed from an employee's inherent need for affiliation, achievement, competency or belonging (Organ, 1988), that primarily occurs when he or she feels the responsibility to reciprocate, as it may happen in situations where servant leadership exists (Newman et al., 2017). Owing to the high concern of servant leaders toward the growth of their subordinates (Eva, Robin, Sendjaya, van Dierendonck, & Liden, 2019), such leaders are likely to be admired and, accordingly, the subordinates may have a perception of psychological imbalance through their relationships with their leaders, provoking them to have a feeling for the responsibility to reciprocate with favorable behaviors at the workplace, for instance OCB. Takeuchi et al. (2009) illustrated that servant leaders improve the motivation, abilities and interests of employees to leverage OCB via their behavior of serving or shaping organizational culture. That is, servant leaders have a vital role in reinforcing the culture of the organization and inspiring their followers to engage in OCB through making significant contributions that exceed their duties and responsibilities which are specified in the job description or contractual agreements (Farh et al., 2004).

Another purpose for the current research was to test the impact of ethical leadership style on employees' creativity and verify whether OCB acts as a key mediator between both constructs. The findings provided support for the significant linkages among ethical leadership style and employee creativity, ethical leadership and OCB, and OCB was found to be a significant mediator among ethical leadership style and employee creativity. Prior researches also confirmed that ethical leadership style is a significant predictor of OCB (Nemr & Liu, 2021; Frisch & Huppenbauer, 2014; Yang & Wei, 2018; Wang & Sung, 2016). Studies that explained the linkages among ethical leadership and OCB have predominantly employed both of social exchange theory as well as social learning theory. This paper reveals that the empirical linkages among ethical leadership style and OCB is positive and statistically significant. If employees perceive their superiors to be fair in distributing the responsibilities and rewards without discrimination, they tend to foster positive attitude at the workplace. Moreover, ethical leaders tend to respect all of their followers equally, mediate fairly, communicate openly and lead by example. These behaviors tend to exhibit positive impact on employees' attitudes and inspire them to engage in OCB.

Additionally, the findings outlined that ethical leadership style positively predicts employee creativity. More support can be seen in the theoretical literature which depicted that ethical leadership style positively affects the attitudes and behaviors of organizational employees (Li et al., 2022; Kalshoven et al., 2011; Zhu, May, & Avolio, 2004). The result is in line with those of past researches which confirmed the positive linkages among the ethical leadership style and creativity of employees (Asif, Qing, Hwang, & Shi, 2019; Javed et al., 2018; Chughtai, 2014; Ma et al., 2013). Brown et al. (2005) also demonstrated that ethical leadership style was positively linked with employee creativity as ethical leaders institute the moral values at the workplace, communicate openly with their followers, respect the, make fair decisions, stimulate them to share their opinions and are perceived as trustworthy. Finally, the results verified that OCB has a strong mediating role among ethical leadership and individual creativity. The result showed empirical support for the suggestions of Liden et al. (2014) who declared that mediating variables should be existent in the relationship among servant leadership style and individual behavior. Thus, by adopting ethical leadership style and engaging in OCB, employees can be motivated to brainstorm new or novel ideas and show their creativity behavior in the firm (Tu & Lu, 2016).

6. Implications

This paper makes a significant contribution to the empirical literature on servant and ethical leadership. First, it shows that employees in the higher education context may score better on OCB when they are led by ethical and servant leaders. These findings complement those of previous studies in other sectors and show the significance of bringing on board servant and ethical leaders in supervisory roles to promote behaviors that go beyond statutory standards. In addition, this study exposes the methods through which servant and ethical leaders stimulate greater degree of employee OCB in the education sector, which is of critical importance. Determining how supervisors and leaders may foster OCB among higher education sector personnel is very important for the survival and competitiveness on the institution. Furthermore, this study adds to empirical research by collectively examining servant leadership, ethical leadership, employee creativity and OCB in one model. In the past, ethical and servant leadership were confirmed as important determinants of employee OCB (Chon & Zoltan, 2019), but there has not been any research examining these factors together. There is a need for more empirical studies on servant and ethical leadership styles and their effects on key individual outcomes (employee creativity and OCB), which are critical to the growth of higher education institutions.

This study provides us with greater understandings about the association among leadership style and individual creativity via the mediating role of OCB. It is evident that employees nowadays demand more ethical and servant leadership styles that emphasize personalization. Due to their intrinsic focus on addressing followers' needs, ethical and servant leadership styles focus on meeting employees' expectations. As a result, supervisors at workplace should be encouraged to adopt both ethical and servant leadership practices. The study also shows the important role of employee confidence in leaders and their creativity outcomes. Under the guidance of trustworthy leaders, individuals are more likely to thrive. Therefore, our findings add to the prevailing knowledge on how leadership behavior affects creativity on various fronts and levels. Lastly, our study is one of the few to inspect the impact of leadership at different levels. According to Yoshida et al. (2014), effective servant leadership fosters individual and team innovation by promoting individual and collective leader identification, as well as collective leader prototyping.

7. Limitations and future research

Similar to other researches, there are several limitations in this paper that should be considered in the future. First, only two leadership styles were examined in this paper to determine their significance in shaping employee creativity. Therefore, future studies are recommended to test other leadership styles, such as authoritarian and autocratic leadership. Second, the data were analyzed using the partial least squares technique (PLS-SEM) to test the hypotheses and draw conclusions. We suggest that longitudinal examination should be directed in the future to acquire a superior comprehension of the likely effect of selected leadership styles on employee creativity. Third, the demographic variables used in this study were excluded from the analysis. Thus, it is suggested for future studies to test the moderating effects of demographic factors (e.g. age, gender, income) in the relationship between selected leadership types and employee creativity. Moreover, this paper used OCB as a key mediator between two leadership types and employee creativity. Hence, it is recommended for future researches to examine other mediators to better understand the way in which servant and ethical leadership impact employee creativity. Additionally, the survey responses for this paper were gathered from employees in higher education sector. Consequently, additional research in other sectors and cultures is needed to discover if the theories utilized to explain all the relationships explored in this study are context-sensitive, and whether the outcomes of this paper can be extended to different contexts. Finally, the COVID-19 crisis may have an impact on the accuracy of data collection due to the difficulty of reaching the participants physically and distributing the survey to them.

Figures

Figure 1

Measurement model

Table 1

Correlations, mean and standard deviation

Construct	Mean	SD	1	2	3	4
1. Servant leadership	3.96	0.847	1
2. Ethical leadership	3.93	0.832	0.411**	1
3. Employee creativity	3.87	0.707	0.549**	0.514**	1
4. OCB	4.02	0.875	0.472**	0.598**	0.605**	1

Note(s): **p < 0.01

Table 2

Confirmatory factor analysis

Construct	Item	Factor loadings	Cronbach's alpha	Composite reliability	AVE
Ethical leadership	EL1	0.852	0.939	0.950	0.703
	EL2	0.821
	EL3	0.798
	EL4	0.789
	EL5	0.848
	EL7	0.914
	EL9	0.847
	EL10	0.833
Servant leadership	SL1	0.740
	SL2	0.782
	SL3	0.890
	SL4	0.877
	SL5	0.880	0.965	0.970	0.728
	SL6	0.906
	SL7	0.719
	SL8	0.878
	SL10	0.876
	SL11	0.800
	SL13	0.932
	SL14	0.926
Employee creativity	EC1	0.849	0.793	0.866	0.620
	EC2	0.861
	EC3	0.674
	EC4	0.750
OCB	OCB1	0.882	0.892	0.925	0.755
	OCB2	0.865
	OCB3	0.848
	OCB4	0.880

Table 3

Results of hypotheses (direct effect)

Hypotheses	β	t-value	P-value
OCB → Employee creativity	0.387	3.361	0.001
Servant leadership → Employee creativity	0.307	1.974	0.049
Servant leadership → OCB	0.516	2.889	0.004
Ethical leadership → Employee creativity	0.275	1.990	0.047
Ethical leadership → OCB	0.380	2.099	0.036

Table 4

Total effect

Hypotheses	β	Std. deviation	t-value	P-value
Servant leadership → Employee creativity	0.471	0.159	2.959	0.003
Ethical leadership → Employee creativity	0.328	0.165	1.993	0.047

Table 5

Indirect effect

	Hypotheses	Indirect effect	SE	t-value	P-value	Bootstrapped CI		Decision
						95% LL	95% UL
H4	SL → OCB → EC	0.472	0.159	2.968	0.047	0.160	0.748	Supported
H7	EL → OCB → EC	0.328	0.165	1.989	0.003	0.005	0.652	Supported

Note(s): SL = servant leadership, EL = ethical leadership, EC = employee creativity, CI = confidence interval

Table A1

Measurement items of constructs

Construct	Item	Factor loading
Ethical leadership	My supervisor conducts his/her personal life in an ethical manner	0.852
	Business ethics and values are discussed with us by my supervisor	0.821
	My supervisor disciplines the staff who violate the ethical standards in our institutions	0.798
	My supervisor can be trusted	0.789
	My supervisor listens carefully to what we have to say	0.848
	My supervisor makes balanced and fair decisions	0.914
	My supervisor sets as a good example on how to do things the right way with regards to ethics	0.847
	My supervisor has the best interests of the staff in mind	0.833
Servant leadership	At our institution, my supervisor spends the time on forming quality relationships with the department employees	0.740
	My supervisor fosters a sense of community among department employees	0.782
	My department supervisor's decisions are influenced by department employees' input	0.890
	The supervisor of my department tries to reach consensus among department staff on key decisions	0.877
	My supervisor has a sensitivity toward the responsibilities of department staff outside the work place	0.880
	My department supervisor makes the personal development of department employees a priority	0.906
	In our department, my supervisor emphasizes on high ethical standards	0.719
	My department supervisor does what she or he promises to do	0.878
	My supervisor has a wide-ranging interests and knowledge in finding solutions to problems at our institution	0.876
	My supervisor makes me feel like I work with him/her for the best interest of our institution	0.800
	My supervisor always encourages us to be involved in the community service and voluntary activities outside of work	0.932
	My supervisor stresses on the significance of giving back to the society	0.926
Employee creativity	At our institution, I suggest several creative ideas that might enhance working conditions	0.849
	I often participate in suggesting creative solutions to problems at my workplace	0.861
	I am involved in suggesting new ways of accomplishing work tasks	0.674
	I consider myself a good source of creative ideas	0.750
Organizational citizenship behavior	When I have intense workload, I work additional hours, by minimizing the normal breaks or staying in office later than usual	0.882
	I frequently share my opinions to improve my department	0.865
	I often do more than the job I am paid to do	0.848
	Even when it is not compulsory, I try to assist the new members of my department	0.880