THE MODERATING ROLE OF PERCEIVED REWARD ON LEADERSHIP STYLE AND POLICY INVOLVEMENT EFFECTS ON JOB PERFORMANCE AMONG PHARMACEUTICAL MANAGERS

Management and behavioral sciences literature has established a direct link between rewards and employee performance. However, limited research exists on the role of perceived reward on the effects of policy & strategy involvement and leadership style on the performance of pharmaceutical managers. Intuitively, perceived rewards


A. INTRODUCTION
The pharmaceutical marketing industry is typically a high-performance-driven environment in which product sales volumes and targets are pursued by the sales workforce managed by a dedicated team of managers to provide coordination and direction (Rezvani, Management teams in the pharmaceutical industry are broadly divided into-strategic and operational managers.Strategic managers are primarily relevant to the design and development of policies, strategies, and tactics that would guide the operations of the teams (Oamen & Omorenuwa, 2022;Rezvani. 2017;Tokarski et al., 2016).They are responsible for translating the overall vision of the business owner into actionable objectives.On the other hand, operational managers are entrusted with ensuring that the day-to-day tasks and tactics are executed according to the policies and guidelines of the strategic managers (Oamen & Omorenuwa, 2022).
This study is significant because it addresses the issue of perceived rewards from the perspective of pharmaceutical managers using the lens of the incentive theory of motivation in the context of the influence of their leadership styles and involvement in policy and strategy on performance outcomes.The objectives of the study were to investigate the causal effect of leadership style, policy engagement, and reward system on organizational performance and the moderating effect of reward system among pharmaceutical managers using structural equation modeling (SEM), secondly, using multigroup analysis to evaluate the comparative differences in path estimations based on managerial roles.

Incentive theory of motivation
The incentive theory of motivation is a psychological theory proposed by Skinner (1953) that suggests that the motivation to engage in positive and desirable behavior is influenced by incentives, rewards, or positive reinforcements.The theory expounds that an employee is motivated to behave in a certain way or exhibit certain behavior because of expected rewards.
In other words, behavioral constructs such as appropriate leadership and active involvement in policy and strategy development for pharmaceutical managers are motivated or enhanced in the presence of rewards and incentives.The incentive theory has been extensively applied to study employee behavior in human resource management, education, and healthcare (Frengki et al., 2017;Manzoor et al., 2021).A study by Oamen (2021) revealed that motivation to engage in work activities is linked to the availability and adequacy of incentives and rewards that impact pharmaceutical executives' job satisfaction (Oamen, 2021).In the context of this study, applying the incentive theory of motivation, pharmaceutical managers are potentially encouraged to exhibit leadership and policy involvement behaviors depending on the perceived reward level.

Management Groups
The Management groups assessed in the study were operational and strategic management roles.Operational sales managers are first-level managers who supervise field sales executives and monitor the execution of set organizational goals.They are often located in territories or regions of the country of engagement ( Oamen & Omorenuwa, 2022;Rezvani. 2017;Tokarski et al., 2016).On the other hand, strategic managers are sales and marketing department heads and typically represent senior management.They are responsible for determining policies and strategies for pharmaceutical companies.They play overarching and direct supervisory responsibilities over operational managers and the entire sales workforce (Rezvani, 2017;Tokarski et al., 2016).

Organizational Job Performance (OPM)
OPM refers to the positive and productive effect of pharmaceutical managers' activities towards attaining set sales and marketing goals of their respective managerial roles in the organization (Berberoglu andSecim, 2015: Babelova et al., 2020).OPM, from the perspective of managers, provides a basis to assess the extent of attainment of set organizational objectives.
In a competitive industry like pharmaceutical marketing, periodic and regular performance or impact management is essential to ensure that key organizational objectives and processes are aligned with the organization's strategic goals.Pharmaceutical managers are expected to preemptively evaluate their impact on the organization before their superiors or human resource managers deploy formal performance or impact assessment measures.Critical areas or performance impact indicators covered are-resource utilization, profitability, revenue generation, operational cost management, team productivity, and team management (Jusoh et al., 2008: Daniela & Queiroz, 2013).In the context of this study, a focus is placed on the selfassessment of pharmaceutical managers as to their impact on the organization (Oamen & Omorenuwa, 2022).

Leadership Style (LS)
Leadership style (LS) implicitly refers to the ways and patterns of behavior by managers through which managerial influence is exerted in the pursuance of set objectives and goals in an organization (Mitonga-Monga & Coetze, 2012;Ojokuku et al., 2012).LS is a key driver of organizational impact or performance.Studies have shown a direct relationship between leadership styles or methods and organizational performance.In other words, how employees perform in an organization depends on how they are managed or led.Several studies suggested that various leadership aspects are expressed at varying adapted levels depending on the situation faced by the manager (Ojokuku et al., 2012).Such styles include participatory, autocratic, consultative, democratic, transactional, and bureaucratic styles (Nwadukwe & Court, 2012).Studies have established a strong positive relationship between LS and OPM (Ojokuku et al., 2012).However, in the pharmaceutical marketing industry in a developing country like Nigeria, there is a need to explore how managers perceive the relationship between LS and OPM.

H1
: There is a significant influence of leadership style (LS) on the organizational performance (OPM) of pharmaceutical managers.

Policy and Strategy Involvement (PSI)
Managers, by role definition, have crucial roles to play in formulating, communicating, and implementing policies and programs that shape the direction and performance of their organizations (Al Khajah, 2018).PSI is essentially a multidisciplinary, interdepartmental, interactive, and continuous process involving every level of management.Scholars posit that it should be developed by involving every stratum of human resources (stakeholders) available in the task environment (Bruijn & Heuvelhof, 2002;Tohidi & Jabbari, 2012;Ornoy, 2010;Kumar & Saha, 2017).In every organization, employees are advocated to be involved in the decision and policy-making process.Studies have shown that there is collective gain, enhanced motivation, and common purpose when policies are inclusive or participatory (Kumar & Saha, 2017), thus tendings to support the ease of execution at the operational level.Lower levels of participation or involvement tend to reduce the commitment of the manager to take ownership of policies and strategies (Kumar & Saha, 2017).

H2
: There is a positive influence of policy & strategy involvement (PSI) on the organizational Impact (OPM) of pharmaceutical managers.

Perceived Reward (RP) as a Moderating variable
Rewards are considered to be the extrinsic and intrinsic consequence of work done as well as the consequence for the productivity of an employee.Extrinsic rewards include salaries, incentives, and career advancement for acceptable performance, while intrinsic rewards include verbal commendation, appreciation, and recognition for efforts.It is established in the literature that rewards have been proven to strengthen motivation and invariably enhance performance (Ngwa et al., 2019;Allen & Helms. 2002).Studies have shown that adequate rewards for employee impact performance enhance the tendency of employees to add more value to their organizations (Allen and Helms. 2002).RP has been shown to play an integral role in motivating employees' best behavior and attitudes, especially in the pharmaceutical marketing industry, where it essentially shapes employee perception (Manzoor et al., 2021;Oamen, 2021).Furthermore, high levels of RP have been linked to improved motivation of employees, which invariably impacts their performance at work (Frengki et al., 2017: Manzoor et al., 2021;Silverman et al., 2016).There is a need to provide empirical evidence to show how RP influences the relationship between LS and PSI on OPM among pharmaceutical managers.

H3
: Perceived reward (RP) strengthens the influence of leadership style (LS) on organizational impact (OPM).

Multigroup comparison between strategic and operational Managers
In line with recommendations by some authors (Sarstedt et al., 2011;Oamen, 2023: Oamen & Ihekoronye, 2022).it is relevant to explore whether likely differences in perception exist between groups or categories in the study (strategic and operational sales managers) using a multigroup analysis algorithm in SEM.This is a preferred approach instead of making inferences based on the single path output of the structural model.

H5
: There is a significant difference in perception between strategic and operational pharmaceutical managers.

Measurement Invariance Assessment of Multigroup Model
Measurement invariance testing is an important estimation, particularly when a researcher wants to ascertain that any significant difference between groups is not due to instrument bias, in which case, the respondents in both groups tend to understand the contents of the research instrument (questionnaire) differently (Oamen et al., 2022;Oamen & Ihekoronye, 2022).In this study, two groups were assessed for invariance-strategic managers and operational managers, using the measurement algorithm in WarpPLS (Kock, 2022).
Therefore, a non-significant difference between both groups implies that respondents properly, equally, or equivalently understood the instrument.

Study design
A cross-sectional questionnaire survey with data randomly collected from a stratified sample of two hundred and forty-one [N=241] managers (comprising 103 strategic managers and 138 operational sales managers, respectively) involved in pharmaceutical marketing in Nigeria.Participants are managers who occupy operational sales and strategic managerial portfolios, respectively.Data was collected over three months, from 1 st September to 30 th November 2021.The sample size computation was based on a proposed size of 234 using the gamma-exponential method for structural equation models (Kock & Hadaya, 2018).The parameters used for determination were an absolute path coefficient of 0.2, a statistical power of 0.8, and a significance of p < 0.01.Respondents gave consent before filling out the questionnaire.

Common Method Bias (CMB)
Common method bias or response bias was preemptively addressed during the questionnaire design by varying response types to the questions (Jordan & Troth, 2020;Chin et al., 2012).However, Harman's single-factor method was used to assess CMB by applying the SPSS factor analysis algorithm to rule out the possibility of bias.A variance of 20.24% accounted for variability for the single factor computed, which is below the cutoff (benchmark) value of 60% (Jordan & Troth, 2020;Chin et al., 2012).

Measurement of Variables
The variables used in the study were measured by indicator items using the Likert scale.
Table 1.Constructs and indicators items of the study Source: primary data processed, 2023

Data Analysis
Data were analyzed using IBM SPSS version 25 and WarpPLS version 8.0 (Kock, 2022).
Structural equation modeling (SEM) analyses were used to evaluate both the measurement and structural models of study variables; LS, RP, PSI (independent variables), and organizational impact OPM (dependent variable).Multigroup analysis was used to explore differences in the relationship.The measurement invariance assessment was achieved using the Satterthwaite algorithm in WarpPLS software (Kock, 2022).The robust path analysis algorithm in WarpPLS was used to estimate the structural model.

Response Rate and Demographics of the study population
A total of two hundred and forty-one managers out of three hundred questionnaires administered filled the questionnaire with a response rate of 80.3%.The average age of respondents was 35.5 years, and the average years of experience in management were 7.5, while years in the pharmaceutical marketing industry averaged 8.6.Regarding demographic attributes, 103 representing 42.7%, were strategic managers, and 138 were operational sales managers representing 57.3%.

Model fit and test for collinearity Measure of Measurement Model
The goodness of fit statistic depicted by SRMR (standardized root mean squared residual) was 0.092, which fell within the acceptable range of less than 0.1 (Kock, 2022).Table 2 shows the reliability and validity values of constructs and their indicators compared to the set criteria.It showed that the four constructs met the criteria for inclusion in the measurement model (Taber, 2018).The VIF values of indicators were all less than the cutoff value of 3.0, hence eliminating multicollinearity concerns (Kock, 2022).The Heterotrait Monotrait (HTMT) criteria for discriminant validity showed that all constructs had values less than the cutoff value of 0.85, as shown in Table 3, thereby confirming the uniqueness and separability of constructs.(Henseler et al., 2012;Taber, 2018).

Coefficient of Determination (R2)
The r-squared value (R 2 ) was 0.268, which implies that approximately 27% of the variance in the outcome variable (OPM) is explained by the independent variables (LS, PSI, and RP).Similarly, the Q 2 value was 0.271, a measure of the predictive value of the structural model.Both indicators showed reasonable predictive validity of the model since the proposed threshold of 0.1 [10%] was not violated (Henseler et al., 2015;Kock, 2022).Source: primary dated processed, 2023 Table 4 showed that both PSI and LS had a significant positive influence on OPM with small effect sizes based on Cohen's specification of 0.02 to below 0.15 range (Cohen, 1988).
Also, results showed that RP had a negative and significant effect (f 2 = 0.034) on the relationship between PSI and OPM, while there was no moderating effect of RP on the relationship between LS and OPM.This is depicted diagrammatically in Figure 1.Table 5 shows the output of the multigroup analysis of the significant paths of the structural model.It showed that the path coefficient of strategic managers was higher than that of operational managers in the relationship between PSI and OPM.Source: primary dated processed, 2023 Table 6 shows the output of measurement invariance assessment using the Satterthwaite analysis method in WarpPLS to compare the indicator loadings of strategic managers versus operational managers to ascertain any difference in constructs.Results showed that all indicators apart from OP5 were not statistically different from each other at the 2-tailed pvalue.Hence, overall measurement invariance is achieved.In Figure 2, a visual inspection of the moderation graph shows that a low perceived reward (RP) has a significant negative dampening or weakening effect (steeper line) on the positive relationship between PSI and OPM compared to a high perceived reward (RP) which tends towards zero (flatter line).
This study used SEM to test the study hypotheses on the causal relationship between independent variables (LS, RP, and PSI) and dependent variables (OPM) among pharmaceutical managers.The multigroup difference of path estimates of strategic and operational sales managers was also explored.
From Table 5, the positive and significant effect of LS adopted by managers on OPM aligns with several studies in the literature (Ojokuku et al., 2012;Mitonga-Monga & Coetze, 2012;Nwadukwe & Court, 2012;Ebrahim, 2018).Hence hypothesis H1 was supported by the findings.This finding suggests that the type of LS adopted by a manager impacts his or her level of performance or impact in the organization.Invariably, the use of consultative, democratic, transactional, and bureaucratic styles of leadership was significant, as depicted by significant factor loadings of indicator items.However, participatory and autocratic LS were excluded due to low factor loadings, thus implying that pharmaceutical managers did not deploy the LS approaches in their operations.Furthermore, the significant effect of PSI on OPM confirms the assertion that the more involved a manager is with the policy, strategy, and decision-making process, the higher the tendency to improve performance.In other words, higher PSI engenders greater feelings of ownership and motivation to ensure the successful execution of agreed goals (Tohidi & Jabbari, 2012;Bruijn & Heuvelhof, 2002).This result explains an important aspect of management, especially due to increasing complexities in management structure and role.These structural relationships are depicted in Figure 1.
Furthermore, the influence of PSI on OPM was positive and significant, thereby supporting hypothesis H2.This result aligns with the literature on the level of involvement in generating the policies and strategies that impact operations and performance.The more an employee is involved in strategy formulation, the higher the sense of purpose and motivation to ensure performance (Ornoy, 2010;Kumar & Saha, 2017).However, for the managers sampled for this study, the PSI had a relatively stronger influence on OPM than LS (0.304 vs. 0.303).This result implies that involvement in policy and strategy is of more relevance to their overall performance than the style or type of leadership adopted by the manager.
In Figure 2, the simple slope analysis model showed that when pharmaceutical managers had a low perception of reward, it dampened the impact of policy involvement on performance.
This relationship is depicted by the steepness of the slope or gradient compared to a higher perception of rewards with a flatter line that tends to zero.This finding underlies or underscores the relevance of reward on how managers engage in the policy and strategy sessions that influence their performance outcomes, thus implying enhanced impact in their organizations at higher levels of policy engagement and higher reward systems, suggesting that managers who are actively involved in developing and implementing organizational policies tend to perform better when they are adequately rewarded to a commensurate level for their efforts.This finding is supported by similar outcomes in some published studies which asserted that incentives and rewards improve the impact of employees (Ngwa et al., 2019;Eisenberger andRhoades, 2001: Oamen, 2021).A salient implication of the moderation analysis is that PSI can be substantially supported when adequate rewards and incentives are provided for pharmaceutical managers, hence, strengthening performance since rewards are critical to staff motivation and performance (Frengki et al., 2017: Manzoor et al., 2021;Silverman et al., 2016).Therefore, hypothesis H3 is supported.It is recommended that a reward structure aligned with improved leadership quality and policy development is critical for managers' performance.However, hypothesis H4 was not supported because RP had no moderating influence on the relationship between LS and OPM.This lack of moderating effect may be because LS is either intrinsic personal or learned attributes that do not necessarily require rewards or incentives to be expressed.From the study, RP has a relevant influence on the attitudes and behavior of pharmaceutical managers toward performance at their jobs, especially in the area of policy involvement.This finding implies that pharmaceutical companies should not take for granted the incentivization of work for their operational and strategic managers by focusing only on field sales and marketing representatives (Oamen, 2021), as the absence or inadequacy of it for managers may negatively impact overall organizational performance as a consequence.This result aligns with the incentive theory of motivation, in which case their level of commitment to the formulation and monitoring of policy and beneficial strategies may not be guaranteed to be optimal (Frengki et al., 2017: Manzoor et al., 2021;Silverman et al., 2016).
The comparative multigroup analysis of path coefficients of strategic versus operational managers revealed that strategic managers have a higher and stronger tendency (0.341 vs. 0.267) to be involved in policy and strategy development compared to operational managers, as shown in Table 5.Hence, supporting hypothesis H5 for this specific path relationship only.
This finding is in sync with the primary roles of strategic managers, which are primarily targeted at strategy and policy development to support operational and tactical performance (Oamen & Omorenuwa, 2022;Rezvani. 2017).However, participation and inclusion of operational managers in informing policy with feedback from the field force are highly advocated as they would help to enrich the quality of decisions and execution (Kumar & Saha, 2017).The multigroup analysis affirms the parity of perception among pharmaceutical managers regarding the interaction effects of reward perception and leadership style and the direct effect of LS on their performance in their organizations.Hence, hypothesis H5 was not supported.Therefore, H5 was only supported for the interaction effects of reward perception and policy and strategy involvement.
There were several limitations to the study.The number of constructs and indicators should have been increased to improve construct validity.The assumption for the study's choice and sampling of the managerial roles was based on two major groups only; hence, other managerial groups were excluded.Finally, the SEM study was adapted for a cross-sectional study.Therefore, it is suggested that a longitudinal study survey approach be adopted for future studies.

E. CONCLUSION
The empirical study addressed outcomes that will equip business owners and policy managers with the needed information to improve managers' overall productivity and impact.
The study investigated using the theoretical framework of the incentive of motivation theory, the influence of policy engagement, and leadership styles on organizational performance and was moderated by the perception of rewards in the pharmaceutical marketing industry in Nigeria.Leadership style and Policy involvement had a direct influence on organizational performance.At low levels of perceived reward, managers had lowered the impact of policy involvement on performance.In contrast, no significant effect on performance occurred between the interaction of the moderator and leadership style.The study outcome suggests that pharmaceutical managers' performance is enhanced when actively involved in the policy and strategy development process and adequately rewarded for their efforts.The study affirms that strategic managers tend to have higher policy and strategy involvement than operational managers.For further research studies, there is a need to expand and improve learnings about the role of incentives and rewards on managers' job performance.Hence, the hypothetical model should include job-related behavioral constructs such as employee loyalty, person fit, citizenship, and organizational commitment.

I
Indicator items Code Leadership style (LS)I use a participatory leadership style LS1I used an autocratic leadership style LS2I consult widely before taking decisions-democratic LS3I adapt my leadership style to suit work situations; in policy development at my company PE1My opinion is highly solicited during policy and strategy sessions PE2I provide unsolicited policy/strategy suggestions, PE3The feedback from my team is critical to policy development PE4I adapt quickly to policy shifts or changes PE5I strictly adhere to the given policy and policy changes in my company PE6 SourceBruijn & Heuvelhof, 2002;Tohidi & Jabbari, 2012;Ornoy, 2010;Kumar & Saha, 2017 Reward (RP) I am well rewarded for my efforts RP1I receive significant bonuses and incentives RP2I am paid according to industry standards RP3

Note:
Indicators LS1 and LS2 were removed from the final measurement model due to factor loadings below the benchmark value of 0.5.Threshold values for; a = Factor loading > 0.5; b = Cronbach alpha set at > 0.6 to 0.7; c = CR = Composite Reliability > 0.7: d = VIF = Variance Inflation Factor set at < 5.0.Source: primary data processed, 2023

Figure 2 .
Figure 2. Moderation effects of perceived reward on policy & strategy engagementorganizational performance relationship Source: processed output from WarpPLS, 2023

Table 2 .
Convergent Validity and Multicollinearity Measures

Table 4 .
Path Analysis of Structural Model

Table 6 .
Measurement Invariance Assessment Based on the Management Role