Can employees’ trust their supervisor? The role of high-performance work systems and stewardship climate on employee voice

Abstract

The focus of this research is to investigate the factors that influence employee voice behaviour by examining the integration of high-performance work systems, stewardship climate, and trust in supervisor. Drawing on social exchange theory and leader-member exchange, this study investigates the positive relationship between trust in supervisor, high-performance work systems, stewardship climate and employee voice. Data were collected in three stages from 376 Nigerian telecommunications customer-contact employees. Partial Least Squares–Structural Equation Modelling was used to test the dataset. The findings indicate that high-performance work systems have a favourable association with employee voice, while stewardship climate has an adverse correlation with employee voice. Moreover, trust in supervisor is found to mediate and enhance the favourable relationship between high-performance work systems, stewardship climate, and employee voice. The relevance of this study to service industries, management research, and its practical implications is discussed.

1. Introduction

In the current business landscape, employee voice (EV) is widely regarded as a crucial factor for improving organisational competitiveness and efficacy [[1], [2], [3], [4], [5], [6], [7]]. EV refers to the voluntary and self-initiated actions of employees who express their thoughts and opinions regarding work-related matters through verbal communication, intending to improve workplace conditions and learn from mistakes and weaknesses [8,9]. This behaviour seeks to challenge the established norms and drive positive change [10]. Despite the benefits of EV behaviour (EVB), it is often viewed as risky. For instance, employees may be hesitant to speak up in the workplace out of fear of damaging social relationships or being perceived negatively by others [7,11]. This is especially true when it comes to addressing employers-supervisors’ issues, as they have significant influence over resources and career opportunities [12]. The significance of EV is paramount, given its ability to provide employees with a platform to communicate their ideas and concerns. Through EV, individuals can proactively engage with their workplace and participate in shaping their work environment. Without this outlet, employees may resort to negative actions such as quitting their job, remaining silent about workplace issues, or openly expressing discontent with management decisions and work processes [13,14]. Hence, it is imperative to acknowledge and prioritise the role of EV in promoting a positive and productive workplace culture. The foremost concern of ‘How can organisations influence employees’ voice?’ is a vital question for academics and practitioners, particularly when they have potentially relevant information [15]. The empirical evidence discussed above supports the notion that high-performance work systems (HPWS) [16], organisational climate through stewardship [17], and trust in supervisors (TIS) [18] are crucial factors that contribute to enhancing EVB. These preconditions are crucial in creating a productive and supportive work environment. By prioritising these factors, organisations can create an atmosphere where EV is not only encouraged but also valued and integrated into decision-making processes.

HPWS is a set of HR practices, which can improve employees' capability, willingness, and opportunity to participate, while also enhancing an organisation's sustainability and competitive advantage [19,20]. When implemented appropriately, HPWS can increase employee knowledge, skills, and abilities, leading to improved EV [21]. For instance, HPWS is essential for EV because it may act as a link to build an all-encompassing research model that incorporates the two concepts and highlights their linkages within a unified framework [22,23]. The strategic characteristic of HPWS can influence employees' perception of EVB and provides the appropriate motivation and opportunity to influence their voice behaviour [23]. Therefore, the establishment of a synergistic HR system, known as 'best practice', is necessary in stimulating EVB through HPWS.

[24] highlighted the substantial body of research that has established a relationship between the adoption of HPWS and multiple advantageous outcomes for employees. However, our comprehension of HPWS and its influence on EVB is still evolving [23]. This study, therefore, places special emphasis on employees' perceived HR practices as a key pillar [25]. While most studies view HPWS as an organisational construct with individual outcomes, there is a lack of evidence on how employees' perception of HPWS affects their outcomes, highlighting the need for research on this perspective [[26], [27], [28]]. It is imperative to specifically focus on employees’ perceptions of HPWS (EP-HPWS) [20], as our knowledge about the underlying link with workplace outcomes is not yet comprehensive. Consequently, the present study extended this line of inquiry by further examining the interaction between EP-HPWS and Stewardship climate on EVB.

Management scholars have increasingly focused on how the organisational environment affects the experiences of employees at work [27,29]. This focus is significant because it shapes how employees perceive and interpret events within the organization. Research on organisational climate serves to understand individuals' subjective views of their work environment and how these perceptions influence their behaviour and attitudes. This line of inquiry is also important because it has implications for various individual outcomes, such as trust [30], altruistic behaviour among employees [31], job satisfaction [32], employee voice behaviour [33], and work-related outcomes like performance appraisal [34]. Furthermore, understanding the interaction between individuals and their work environment is crucial in organisational research, and it's impossible to comprehend this dynamism without considering the context itself [35]. In this context, one area that has received less attention is stewardship climate (STC).

STC is introduced as a situational concept [34,36], aiming to improve workplace outcomes by fostering a shared belief that the organisation's policies, practices, and procedures uphold stewardship values. Stewards, who deeply align with the organisation's objectives, integrate this alignment into their mindset, feeling a strong sense of connection and commitment to the organisation. They prioritise cultivating trustworthy relationships with subordinates through self-management and self-control. By establishing a relational and psychological foundation, stewards inspire subordinates to achieve established goals and objectives [37]. Their role is to shape a vision emphasising consistent commitment and excellence in achieving workplace outcomes.

STC is therefore perceived as the collective understanding of job experiences set by leaders who prioritise the organisation's interests over their own, ensuring that employees' best interests are served [38]. This central tenet showcases a significant connection to individual factors and influences various aspects of an organisation, including trust, well-being, satisfaction, performance, and long-term benefits. It is suggested that managers or supervisors, as leaders within the organisation, can align themselves with the company's interests without experiencing conflict. These organisational behaviours are influenced by both psychological and situational factors [37] and the ultimate aim of supervisors [39] is to facilitate optimal coordination among all stakeholders by establishing suitable frameworks and procedures.

As the face of the organisation, supervisors play a crucial role in shaping employee trust, and their actions and support significantly impact employee confidence [[40], [41], [42]]. Employees on the other hand depend on their supervisors to endorse their ideas, and a lack of trust can impede progress [43]. In this context, TIS involves the belief that employees within an organisation act justly when making and executing decisions concerning business procedures in their interactions with their supervisors. Fostering mutual trust between employees and supervisors enables employees to concentrate on their tasks and carry out their responsibilities more precisely [44]. From a relational perspective, this study suggests that employees assess their supervisor's trustworthiness before demonstrating trust in them. Therefore, the trust literature, particularly from an employee's viewpoint, deserves more attention in organisational research as it profoundly influences work outcomes. Further, several theoretical frameworks are based on the proposition that trust is a central influence on varied outcomes [45,46]. Drawing on social exchange theory (SET) and leader-member exchange (LMX) theory [47,48], this study proposes that TIS mediates the relationship between EP-HPWS and STC on EVB, highlighting the importance of employee perceptions of their work environment and trust in their supervisors in fostering EVB [[49], [50], [51]]. The current study also explores the elusive nature of strategic human resource management, a theoretical "black box” conundrum, by examining the role of TIS in promoting and influencing EVB.

This study aims to make several contributions. Firstly, it focuses on the neglected perception and reaction of individual employees in HPWS research [52,53]. Secondly, it adds to the research gap on the relationship between EP-HPWS, EVB, and the role of HR practices. Thirdly, it introduces STC as a situational measure for EV, which has not been tested in the Nigerian context. The study aims to establish the causal relationship among EP-HPWS, STC, and EV, as we explore the mediating role of TIS in this relationship based on SET and LMX. Additionally, while the implications of climate on TIS and EV have been discussed in several studies [27,54], the exact nature of the relationships between STC, TIS, and EV requires further investigation and discussion. Finally, the study uncovers some noteworthy directions for HR and OB practitioners when considering these measures simultaneously.

1.1. Theoretical framework

Social Exchange Theory (SET) is a foundational theory that elucidates workplace behaviour by delineating exchange principles that foster trust and commitment when adhered to by both supervisors and employees. SET, as elaborated by Ref. [55], provides a robust framework for understanding workplace dynamics, especially the relationships between employees and managers. Originating from the seminal works of [56,57], SET draws from psychology and organisational behaviour, conceptualising social interactions as transactions aimed at maximising benefits while minimising costs.

Reciprocity stands as a cornerstone of SET, where the anticipation of mutual benefits for contributions cultivates trust and a sense of obligation within social relationships [58,59]. This norm fosters trust in supervisors, thereby positively influencing employee outcomes [60], highlighting its significance in organisational dynamics. These principles of reciprocity and repayment instil a sense of obligation among employees to reciprocate the HPWS provided by the organisation. Consequently, this engenders greater employee engagement with their work, leading to improved outcomes.

It is also important to note that, the quality of reciprocity varies depending on factors such as the nature of the relationship, the environment, and individual beliefs, which aid in identifying the optimal response to maximise benefits for the recipient [48,[61], [62], [63]]. Furthermore, this perspective is enriched by considering incentives and costs, with employees acting as rational agents striving to optimise their social connections [56].

LMX theory delves into the interactive relationship between supervisors and employees, aiming to foster reciprocal stewardship behaviour within organisations. The theory draws its theoretical and empirical underpinnings from SET [57], which posits that employees feel compelled to reciprocate when treated well by their supervisors. It primarily focuses on the significance and value of the shared relationship, also known as the vertical dyad or dyadic relationship [64] between the leader and their follower. At the core of leader-member exchange lies the concept of mutual trust and loyalty [65]. This concept underscores that leaders in various settings are entrusted with the responsibility of looking after their followers, while followers, in turn, have an ethical obligation to respond with utmost respect and loyalty to their leaders [66].

LMX theory also examines the impact that relationships between leaders and followers have on an organisation [67]. asserted that almost all literature on LMX suggests that high-quality relationships, characterised by high levels of trust and enhanced communication channels, yield positive benefits both for followers and the organisation they serve, thereby fostering mutually satisfactory exchange relationships.

According to Ref. [68], employee roles within an organisation are gradually established through informal exchanges between the leader and their followers. Researchers [69,70] have suggested that these roles evolve through mutual agreement between the leader and follower, with both parties believing that the outcome will benefit them. Consequently, a level of confidence develops between the leader and their followers [68,71,72]. Thus, LMX underscores the importance of situational mechanisms for stewardship to thrive and demonstrates that employees' job roles influence their perception of stewardship and trust within the organization [47,70,73] as a means of enhancing their overall contribution within the organisation.

1.2. Conceptualisation and hypotheses

EP-HPWS is viewed from a systems perspective, with prior research suggesting a mutually reinforcing synergistic effect. This study examines EP-HPWS factors collectively on various HR practices, rather than individually [74]. Recent research has shifted focus from EP-HPWS in manufacturing to its application in the service industry [[75], [76], [77], [78]]. Hence, this study, as earlier indicated, selected four critical indicators of EP-HPWS (selective hiring, contingent compensation, extensive training and teams, and participation). These HRM practices are considered highly effective, especially in the service sector.

In line with the aforementioned, trust in supervisor (TIS) perception is an important factor in this relationship with EP-HPWS [79]. describe trust as a concept that encompasses the belief in the consistent actions of another party, even in situations where the trustor lacks the ability to monitor or control those actions. This conviction involves an openness to being exposed to the actions of the counterparty, arising from the trustor's expectation that said actions are of significance to them.

Specifically, employees trust their employers to guide them in unexpected and precarious conditions with sincerity and reliance. Furthermore, in this research, TIS shows an employee's willingness to trust their employers' actions or intentions.

Several researchers have found EP-HPWS to be correlated with trust [54,[80], [81], [82], [83], [84]]. Such evidence indicates that the current study's hypothesized relationships can be investigated under the guidelines of SET [61]. propose that social exchange connections involve the exchange of socio-emotional benefits tied to personal relationships and reciprocal obligations. The norm of reciprocity suggests that when employees receive opportunities and recognition for their performance from their supervisor, they are motivated to work and experience a strong sense of commitment and involvement within the organisation. Congruent with the aforementioned, these practices can boost EP-HPWS, motivating employees to reciprocate their employer due to their perceptions of being valued in the organisation. In line with our discussion and the connection between EP-HPWS and trust, we recommend that EP-HPWS influence their trust in their supervisors.

H1

Employees' perceptions of HPWS will be positively associated with TIS.

Studies indicates that supervisors actively participate in the implementation of formal voice channels and HRM guidelines. This is enhanced by the presence of an effective EP-HPWS, which encourages positive attitudes towards employee participation through HRM factors like training and compensation [85]. Notwithstanding, self-interest, loss aversion, or lack of confidence may deter employees from proffering ideas or suggestions [85]. It is, therefore, crucial to note that the sharing of such ideas is a critical component in the accomplishment of organisational objectives [86,87], and success depends on supervisors' anticipated success, openness, and belief [8,88].

Therefore, their actions in conjunction with EP-HPWS practices influence employees towards positive outcomes on issues and concerns in the work environment (employer-employee interest). SET considers these practices as a source of motivation and commitment based on the principles of reciprocity. EP-HPWS show that an organisation aims at investing in and increasing the values of its human capital, and at the same time, employees express positive behaviour towards the organisation [57,89,90]. Recent studies [19,27,91,92] have established positive associations between EP-HPWS and EV. Consequently, we put forward the following hypothesis.

H2

Employees' perceptions of HPWS will be positively associated with EV.

Supervisors play a crucial role and are a key factor in developing or shaping employees’ behaviour/perception of trust [93] while affecting EVB within the work environment [94]. In such a trust relationship, employees expect that through uncertain and vulnerable situations, the supervisors can be relied on within their work environment. Therefore, it can be considered that TIS is the actions or intention of supervisors towards their employees and the belief and expectation that the likelihood of such actions will be beneficial, favourable, or non-detrimental [75,95].

EV exists to exert employees’ influence on their supervisor or management while aiming to improve their work environment. Extant research on voice behaviour has reiterated that the decision to/not to engage in it is hinged on the assessment associated with the expectation of voice (i.e., potential cost and benefits) [96]. It is also important to recall that EV is conceptualised as an outcome of trust in this study. This study thus maintains that TIS will positively impact the willingness of employees to voice their opinions and concerns [97].

According to Ref. [57], SET contends that for employees to feel comfortable expressing their opinions, trust must be cultivated not only through the process but also with the supervisors. If this social exchange cannot be established, the best approach is silence [12]. The responsiveness of supervisors is a vital element of engaging employees in voice [98]. Therefore, the key factor in attaining positive work-related outcomes within this reciprocal exchange is the trust in and relationship with supervisors [23]. Empirical studies have indicated that establishing trust between employees and supervisors is most effectively achieved through face-to-face meetings [99], while organisational trust was also found to be positively linked to EVB [12,100]. The weight that trusts holds in employees' assessment of their ability to participate in a collective voice mechanism was corroborated by Refs. [101,102]. In addition [[103], [104], [105], [106], [107]], studies established a strong correlation between leadership trustworthiness and EV. Accordingly, the following hypothesis is developed.

H3

Trust in supervisors will have a positive effect on EV.

Organisational climate encompasses a variety of employee assessments [108], as well as collective assessments of their work environment [109]. The concept of organisational climate can be derived from STC, which indicates the degree of employees' perception in which their organisation's policies, practices, and procedures promote behaviours of stewardship [110]. STC can be categorised into six interconnected factors that encapsulate non-economic and other-focused behaviours [110]. Supervisors play a significant role in shaping stewardship behaviours, and their behaviour and underlying motives can shape employee attitudes towards organisational priorities and management practices [110,111]. TIS is a critical component that influences decision-making, overall security, employees' behaviours, and well-being [112,113]. EV is also important, as it emphasises the constructive expression of concerns to improve issues, not just criticism, and is effective when embedded in a supportive and fair climate [36,114]. These constructs consider the psychological state and motivation of members, which should influence the behaviour and intentions of both organisational actors [30,108,112].

This study builds on the concepts of SET and LMX [38,61] to propose that leaders, particularly those who exhibit stewardship behaviour, can shape the organisation to foster similar behaviours in employees. By establishing reciprocal stewardship dynamics between supervisors and employees, a culture of trust and extra-role communication can develop throughout the organisation. What constitutes climate has been found to influence trust and extra-role communication behaviours, emphasising the importance of organisations and supervisors in shaping employee perceptions and actions [27,33,115,116].

The aforementioned justifications predict that STC will result in an increase in both TIS and EV. Consequently, the following hypotheses are set forth.

H4

Stewardship climate will be positively related to TIS.

H5

Stewardship climate will be positively related to EV.

This section argues that TIS facilitates the simultaneous effects of both EP-HPWS and STC on EV. The hypotheses put forth in the previous literature suggest that the relationship among these factors may not be direct or unconditional, but rather mediated by other variables. For instance, trust plays a critical role among work outcomes relationships [104,117,118]. These studies investigated trust either from management or employee's perspective as a key factor, which had a strong and positive association with EP-HPWS and variables such as perceived organisational support, employee attitude and commitment [104,117,118]. Recent studies by Ref. [30] support the positive impact of trust on job performance and the relationship between expectation climate strength and performance. Through the mediating role of employee trust [76], demonstrated that HPWS-related HRM initiatives exerted a favourable impact on service quality. Again, regarding the relationship between psychological contract breach and EVB [95], emphasises the role of trust in an organisation [93]. found that TIS fully mediated the effects of supervisory support and employee engagement on direct voice, while [50,105,119] confirm the intermediating position of TIS between supportive leadership, perceived supervisor voice behaviour, and EV [120]. demonstrated that the relationship between organizational justice and employee engagement was mediated by organizational trust.

Drawing on SET and LMX, it can be posited that employees are motivated to reciprocate positive interactions with their supervisors to foster and sustain high-quality social exchanges within the organisational context. This reciprocal behaviour is contingent on employees' perceptions of their supervisors, which are shaped by trust. In the context of increased social interaction, employees are expected to demonstrate both in-role and extra-role behaviours. As a result, it is reasonable to expect that these theories will significantly impact the adoption of EP-HPWS and STC activities, ultimately influencing employees' EV through the mediating mechanism of TIS. Therefore, the following hypotheses are proposed.

H6a

Trust in supervisors will mediate the relationship between employees' perceptions of HPWS and EV.

H6b

Trust in supervisors will mediate the relationship between STC and EV.

2. Method

2.1. Participants and procedure

The sample in this research consists of customer-contact employees in Nigeria's telecommunications industry, which has been underrepresented in current service-related studies. Under the Nigerian communication commission database [121], Nigeria has four major telecommunications companies (market size and revenue generation). To ensure that the aim of the study was clear and to secure permission for data collection, the researcher drafted a formal letter to the management of the company. Management of these companies granted permission for data collection. The purposive sampling technique was utilized to collect data. The collection process was done from July 2022 to September 2022. An overwhelming majority of the questionnaires distributed (94 %) were returned to us, totalling 376 completed surveys. The bio-data collected from these surveys, including details about demographics, can be found summarized in Table 1.

Table 1.

Demographic.

Demographics category	Frequency	Percentage (%)
Gender
Male	178	47.3
Female	198	52.7
Age
18–27	3	0.8
28–37	254	67.6
38–47	114	30.3
48–57	5	1.3
Education
HND	13	3.5
Bachelors	321	85.4
Masters/PhD	42	11.2
Marital status
Single	137	36.4
Married	239	63.6
Years of employment
Under a Year	5	1.3
1–5 Years	118	31.4
6–10 Years	226	60.1
11–15 Years	27	7.2

The sample consists of the number of respondents (male and female), which was closely matched, with more females (52.7 %) than males (47.3 %). The age group was distributed in five categories amongst the respondents as follows: 18–27 (0.8 %), 28–37 (67.6 %), 38–47 (30.3 %) and 48–57 (1.3 %). The majority of the respondents were bachelor's degree holders (85 %), followed by masters/PhD (11.2 %) and HND (3.5 %). Most respondents were married (63.6) and others were single (36.4 %). Among were 5 respondents who had under a year of work experience, out of 376 respondents, 226 (60.1) had 6–10 years of work experience, followed by 118 (31.4) respondents with 1–5 years of work experience and 27 (7.2 %) had 11 years of work experience.

To avoid selection bias, specific measures were implemented such as the use of reverse-scored items and confidentiality of information. Employees were provided with individual envelopes to return their questionnaires and reminded to seal them properly. These measures are expected to reduce common method bias [122]. Additionally, three employee surveys were administered at distinct time intervals (Time I, II, and III) with a two-week gap between each survey to comply with temporal separation guidelines [122,123]. The methodology aligns with established empirical research standards [104,124].

2.2. Non-response test

We examined the responses of individuals who participated early and those who participated late during data collection across the three distinct time intervals, a phenomenon known as the non-response test [125]. The responses from both early and late waves of collected questionnaires were scrutinized to address non-response bias [[125], [126], [127]]. The full responses of the first 50 participants (early-wave group) were compared to the partial responses of the last 50 participants. After conducting T-tests on the two groups (HPWS and STC), no substantial differences between the two groups (within a confidence level of 95 %) were detected. Based on this, it can be concluded that non-response bias did not have a significant impact on the outcome of our analysis.

3. Measurement

3.1. HPWS

Four HPWS practices were selected: contingent compensation, extensive training, selective hiring and teams, and participation—the study used items adapted from Ref. [78]. Responses to the items ranged from one (strongly disagree) to five (strongly agree) to evaluate EP-HPWS. To assess the reliability of the construct, Cronbach's coefficient was computed. The obtained alpha value of 0.818 indicates that the construct was reliable and satisfactory. To examine the aforementioned, we used a total of 12 items. Recognising that researchers have suggested that different HRM practises should be viewed as distinct but interrelated dimensions of EP-HPWS, the four-dimensional constructs were analysed using a unidimensional construct [128].

3.2. STC

An 18-item scale by Ref. [37] was utilized to assess employee perception of STC in Time II questionnaire. A five-point Likert scale anchored from one (strongly disagree) to five (strongly agree) was also used to measure their responses. STC was conceptualised as a unidimensional construct and examined the fit of the items using confirmatory factor analysis (CFA). Cronbach's coefficient was used to perform a reliability test. The construct's alpha value was 0.811, showing acceptable reliability.

3.3. Trust in supervisors

In Time III questionnaire, seven items were adapted [129] to operationalize employees' perception of their level of trust. Employee rating for their supervisor consisted of a one (strongly disagree) to seven (strongly agree) scale. To evaluate the consistency and dependability of the construct under examination, Cronbach coefficient as a measurement tool was employed. Our analysis yielded an alpha score of 0.920, indicating that the construct's reliability was deemed to be acceptable and adequate.

3.4. EV

Six items were used to operationalize the EV in Time III. The source of the items was adopted [114], and responses were based on a seven-point scale. The coefficient alpha for the six items was 0.804, indicating acceptable reliability of the construct.

3.5. Empirical analysis

IBM SPSS 23 was used for the initial analysis, encompassing frequencies, summary statistics, correlations among observable variables, and coefficient alpha. This software provided us with the necessary tools to conduct a thorough and precise examination of the data set, allowing us to gain valuable insights and understanding of the information.

CFA was employed with WARP PLS V 6.0 software to evaluate convergent and discriminant validity, along with internal consistency reliability (e.g., composite reliability), following recommendations from Refs. [130,131]. Additionally, the relationship in the structural model was evaluated through structural equation modelling. Overall, partial least squares-structural equation modelling (PLS-SEM) was chosen due to its efficiency in minimising the explained variance in dependent variables, particularly in cases where the data does not follow normality assumptions and important regressors are excluded from the model.

To assess the measurement and structural models, the following global fit statistics were considered: APC (average path coefficient), (GoF) Tenenhaus GoF, SRMR (standardized root mean square residual), SChS (standardized chi-squared), F² (effect size), and Q² (stonegeisser's) [[132], [133], [134]].

4. Results

In the first step, items with low standardised loading were removed for the CFA, consistent with previous studies [135,136]. Forty-nine out of fifty items (loadings) were above 0.70, as shown in Table 2. All composite reliability scores were larger than 0.60 for each of the latent constructs (HPWS 0.894, STC 0.889, TIS 0.938, and EV 0.861), indicating that all measures were reliable [130,137]. All Cronbach's alpha (HPWS 0.818, STC 0.811, TIS 0.920, EV 0.804) were above 0.70 indicating the findings are reliable. It also showed that the average variance extracted (AVE) for each latent variable was above the threshold (0.50); that is, the indicators' principal components were extracted.

Table 2.

The confirmatory factor analysis result (CFA).

CONSTRUCTS	SCALE ITEMS	LOADINGS	MEAN	ALPHA	CR	AVE	FVIF
High Performance Work Systems				0.818	0.894	0.742	1.058
	HPWS2	0.866	3.487
	HPWS3	0.829	3.21
	HPWS5(−)	0.715	3.604
	HPWS6	0.95	3.593
	HPWS7	0.8	3.803
	HPWS8	0.94	3.553
	HPWS11	0.964	4.051
	HPWS12	0.955	3.968
	HPWS14	0.742	3.386
	HPWS15	0.85	3.835
	HPWS16	0.864	3.574
	HPWS17	0.823	3.593
Stewardship Climate				0.811	0.889	0.728	1.064
	STC1	0.907	4.050
	STC2	0.85	3.936
	STC3	0.879	3.517
	STC4	0.836	4.562
	STC5	0.892	4.554
	STC6	0.876	4.666
	STC7	0.841	3.289
	STC8	0.877	3.109
	STC9	0.799	2.509
	STC10	0.804	3.058
	STC11	0.847	2.886
	STC12	0.787	3.037
	STC13	0.906	3.621
	STC14	0.892	3.438
	STC15	0.758	3.345
	STC16	0.89	3.658
	STC17	0.885	3.533
	STC18	0.814	3.334
Trust in Supervisors				0.920	0.938	0.715	1.080
	TIS1	0.787	6.061
	TIS2	0.795	5.444
	TIS3	0.82	6.027
	TIS4	0.883	5.918
	TIS5	0.926	6.117
	TIS6	0.855	6.096
Employee Voice				0.804	0.861	0.514	1.032
	EV1	0.801	5.851
	EV2	0.631	5.856
	EV3	0.51	5.968
	EV4	0.772	6.021
	EV5	0.735	5.803
	EV6	0.806	5.585

Notes: All loadings are significant at 0.01 level. FVIFs = full collinearity variance inflation factors; AVE = Average variance extracted; CR = Composite reliability; (−) denotes reversed score item; ∗ Dropped during confirmatory factor analysis.

FVIF was in line as the results ranged from 1.032 to 1.080. The recommended values are between 1 and 5 to be considered good [138,139]. Based on the findings, it can be inferred that the issue of multicollinearity is not prevalent in the dataset [131,139,140].

An overview of the statistics and relationships of the observed variables is displayed in Table 3. The correlations construct's results were generally consistent at all levels of significance. Notably, EP-HPWS and TIS had an important relationship with EV, while STC had an adverse correlation with both TIS and EV (0.166; −0.103), and EP-HPWS had a significant and positive relationship with TIS and EV. It is important to note that a single index was utilized for HPWS and STC by averaging its items [76,141].

Table 3.

Mean, standard deviation and correlation of observed variables.

Variables	Mean	SD	1	2	3	4	5	6	7	8	9	10
Age	2.32	0.511	-
Gender	1.53	0.500	0.013	-
Education	4.08	0.375	−0.088	0.024	-
Marital stat.	1.63	0.482	0.089	−0.002	0.038	-
Company	2.29	1.186	0.045	−0.045	−0.163b	−0.016	-
YOE	2.73	0.607	0.289b	0.042	−0.049	0.188b	−0.014	-
HPWS	3.62	0.732	0.037	−0.017	−0.137b	−0.007	0.485b	−0.018	-
STC	3.56	0.500	−0.056	−0.039	−0.069	−0.145b	−0.076	−0.116a	−0.121a	-
TIS	5.94	1.105	0.033	0.041	−0.088	0.009	−0.044	−0.066	0.167b	0.163b	-
EV	5.84	0.901	0.526	−0.035	−0.017	0.020	0.098	0.075	0.103a	−0.103a	0.118a	-

Notes: SD= Standard deviation. Gender and marital status were coded as a binary variable (1 = male, 2 = female; 1 = single, 2 = married).

^a0.05 level.

^b0.01 level (two-tailed).

The results of computing the square root of the average variance extracted (AVE) for each variable are shown in Table 4. The findings show that all variables meet the [131] criteria for discriminant validity since, in every case, the square root of the AVE is greater than the correlations between the pairs of latent variables. Moreover, the HTMT criterion was applied to validate the discriminant validity, and the findings indicate that the HTMT values ranged from 0.02 to 0.79, which is below the threshold of 0.90. These outcomes offer statistical assurance for each pair of reflective constructs [142].

Table 4.

Discriminant validity.

	Fornell Larcker Criterion				Heterotrait-Monotrait Ratio
	HPWS	STC	TIS	EV	HPWS	STC	TIS	EV
HPWS	0.699	−0.073	0.224	0.088	–
STC	−0.073	0.596	0.164	−0.110	0.139	–
TIS	0.224	0.164	0.846	0.112	0.237	0.190	–
EV	0.088	−0.110	0.112	0.717	0.146	0.161	0.131	–

Note: The Square root of AVEs is shown diagonally in bold.

The indicators in Table 5 were analysed to determine the model's fitness. Initially, the APC, ARS, and AVIF values [133,143] were examined, which show the average strength and relevance of the variables in the model, the predictive power of the exogenous variables, and the level of multi-collinearity [133]. Also, it was observed that the GoF global index [143] was 0.579 which suggests a large effect size, indicating the overall predictive validity of the model and, more importantly, the SRMR (0.069) is within the acceptable threshold. The overall model appeared to be above average based on the five fit indices.

Table 5.

Model fitness.

INDEX	VALUE	INTERPRETATION
GoF	0.579	small ≥ 0.1, medium ≥ 0.25, large ≥ 0.36
SRMR	0.069	acceptable if ≤ 0.1
SMAR	0.054	acceptable if ≤ 0.1
SChS	4.729	P < 0.001

The model was further tested for predictive relevance, as indicated by the Stone-Geisser Q2 test. The values of EP-HPWS, STC, TIS and EV were 0.591, 0.464, 0.120, and 0.066, respectively. The results indicate the coefficients are greater than zero. The model suggests acceptable model-wide predictive validity as it met the cut-offs for all endogenous LVs (see Fig. 1).

Fig. 1.

The proposed research model.

Table 6 and Fig. 2 display the significant results of hypotheses testing and path coefficient analysis at P < 0.05 level. The empirical data supports H1 and H2, indicating a positive effect of EP-HPWS on TIS (β = 0.293, P < 0.00) and EV (β = 0.121, P < 0.05). The study also finds support for H3, revealing a positive and significant relationship between TIS and EV (β = 0.147, P < 0.00). Furthermore, the data support H4, demonstrating a positive association between STC and TIS (β = 0.209, P < 0.00) and a negative correlation between STC and EV (β = −0.121, P < 0.06). However, hypothesis (H5) predicting a positive correlation between STC and EV cannot be supported by the data, despite having p-values less than 0.01.

Table 6.

Hypothesis testing.

HYPOTHESIS	INTERACTION	COEFFICIENT	DECISION
H1	EP-HPWS → TIS	0.293a	SUPPORTED
H2	EP-HPWS → EV	0.121b	SUPPORTED
H3	TIS → EV	0.147a	SUPPORTED
H4	STC → TIS	0.209a	SUPPORTED
H5	STC → EV	−0.121	NOT SUPPORTED
H6a	HPWS → TIS → EV	0.043a	SUPPORTED
H6b	STC → TIS → EV	0.031a	SUPPORTED

Notes.

^aP < 0.05.

^bP < 0.01.

Fig. 2.

Hypotheses test results.

The inferences regarding the mediation hypotheses were based on a bootstrapping analysis, with 100 resamples and a 95 % confidence interval, which aimed to assess the intervening role of TIS on the interplay between EP-HPWS and STC and their effects on EV. As reported in Table 6, these conditions were met. It confirmed that TIS mediated (significant indirect effects) the relationship between employees’ HPWS perception, STC and EV in a service organisation. EP-HPWS significantly and positively influenced EV via the partial mediating role of TIS while STC influence on EV was significant via the full mediation of TIS. In short, the empirical data provides support for the hypothesized relationships, including H1 to H4 and H6ab.

5. Discussion

This research empirically explores the impact of EP-HPWS, STC, TIS, and EV in a service organisation. It specifically analyses the effects of EP-HPWS and STC on EV and also evaluates the mediatory role of TIS in the relationship between EP-HPWS, STC, and EV.

The study's results indicate that EP-HPWS positively impacted TIS in the service sector. Specifically, our findings suggest that the success of TIS relies significantly on EP-HPWS, aligning with previous research that emphasises the role organisations play in implementing an effective EP-HPWS [54,[80], [81], [82], [83], [84]]. This research illustrates the effectiveness of understanding HPWS as a way to boost trust among employees toward their supervisor. This is because the collection of HR practices is perceived as an indicator that is related to trust [144]. When workers feel trusted by their leader, they may see HPWS as a commitment towards them and as a result, exert more effort in their work.

Second, the findings show that EP-HPWS would promote EV. EP-HPWS had a substantial impact on promoting EV within the organisation through the reciprocal relationship between supervisors and employees [19,21,23,27,91,92]. Supervisors are key actors in implementing HR practices and providing a supportive environment where voice can flourish [145]. Again, an organisation's attitude and behaviour profoundly influence employees' expressive capabilities. Research indicates that implementing HPWS that fosters employee empowerment and voice through specific policies and practices can create a more comfortable and inspired workforce, enhancing their willingness to speak up and share ideas and concerns [100]. This is reinforced by Ref. [50] research on the correlation between HPWS and EV. In this regard, an enabling work environment is pivotal in unleashing the full potential of employees' voices and contributions.

Third, past research has proven that TIS has an immense and positive impact on EV in service-oriented industries [[102], [103], [104],106]. The evidence from this research affirms the connection between TIS and EV in the given industry. It firmly validates TIS as a crucial factor that helps employees express their ideas and speak about their issues freely, thus promoting a comfortable and empowered working atmosphere.

Based on the aforementioned, employees' willingness to trust has a considerable influence on their ability to convey ideas, opinions, and complaints through common voice mechanisms [146,147]. Establishing this foundation fosters a sense of security and comfort, leading individuals to confidently voice their opinions and suggestions on workplace issues, knowing their supervisor's reaction will be supportive.

Furthermore, the intricate connection between STC, TIS, and EV in this study, contributes to the literature by advancing the scholarly understanding and enhancing knowledge in the field. While this relationship is consistent with previous studies that constitute climates (STC) on TIS [115,116,148], STC and EV failed to corroborate with the hypothesis mentioned earlier. Although, it is important to note that [110] research backed the result in a non-family business. Employees tend to have more trust in their superiors when they display trustworthy and responsible behaviour, which is reinforced throughout the organisation. This can create a culture of belief where employees feel more confident in their roles and comfortable carrying out their duties. However, it should be noted that while TIS may enhance the work environment, it does not necessarily affect employees' inclination to voice their ideas and opinions. Taking all into consideration, the result does not imply that STC is unimportant regarding the role it plays on EV in the present study, but rather STC functions differently concerning the variables used and the organisational context.

Succinctly, the study's supplemental findings supported the basic premise by demonstrating that TIS acted as a facilitator in the interaction between EP-HPWS and STC, alongside its influence on EV. This result is vital to support the continued investigation of the challenging task of exploring the black-box phenomena between these relationships. The result supports TIS as a mediator showing a significant positive relationship between EP-HPWS and STC on EV and corroborating past studies [50,76,93,105,118,120]. Furthermore, in line with the theoretical foundation, the study showed that employees would reciprocate with a positive attitude and behaviour when they trust their supervisor will implement the appropriate HR practices and create a conducive environment. At the same time, the dyadic relationship between superiors and subordinates, specifically their bridging ties and generalised norms of reciprocity, has a substantial impact on the future behaviour of EV.

Practical implication

The current study's findings have significant practical consequences for organisations, supervisors, and practitioners. It's worth noting that organisations can increasingly rely on supervisors to implement appropriate HPWS that may be well received by their employees. Indeed, supervisors play a vital role in building trusting relationships since they must be consistent in their behaviours and attitudes, and exhibit equity and support to employees to optimise an organisation's HRM approach [40,149]. Likewise, prior research demonstrates that behaviours that contradict employees' beliefs of fairness and justice may compromise their TIS, diminishing the beneficial impact of HPWS on enhancing employee attitudes [150].

Our findings indicate that EP-HPWS impacted EV in management practices. While businesses' ability to develop employee-centric systems does not guarantee their effectiveness in promoting or discouraging EVB [151]. Organisations need to establish a distinctive set of resources that should allow employees to participate and contribute through suggestions and ideas targeted toward their well-being and, ultimately, the organisation's success. Moreover, organisations should strive to foster an environment that encourages employees to actively participate in decision-making and express their concerns regarding job roles or working conditions.

Specifically, organisational leaders could effectively explore methods to promote self-expression, initiating dialogues centred around EVB. Rather than stifling discussions limited to topics directly pertinent to organisational operations, supervisors could foster informal interactions where employees feel empowered to express themselves openly and candidly to both their peers and supervisors [152]. It is crucial for employees to observe how their thoughts and ideas have been implemented. While this might not be feasible for every individual, there are undoubtedly avenues for reinforcing the impact of changes resulting from feedback and ideas. This could be achieved through platforms by incorporating employee focused generation of ideas as agenda items in both formal and informal discussions [153].

Finally, this research emphasises the importance of TIS in understanding the underlying mechanisms of the “black box” conundrum. It demonstrated that TIS plays a key influence in improving EV through their perception of HPWS and STC. Specifically, employees are more driven and actively engaged when they trust their supervisors. As a result, organisations that want to improve their EVB must guarantee that their employees have a high degree of TIS. Furthermore, understanding the negative impact of supervisors' disruptive actions is crucial, as it can diminish employees' TIS.

Without a doubt, EP-HPWS, STC, TIS, and EV, from a practical standpoint, are significant components and core processes required by service organisations to enhance policies and strengthen employee-employer relationships.

Limitations and future studies

While the study's findings have practical relevance, there are several drawbacks. First, the design's cross-sectional structure precluded us from causal assertions. To establish causal relationships, it is suggested that researchers utilise a longitudinal method in future research. Additionally, it's possible that common method bias could have influenced the current findings since employees were the sole source of all measured variables [123]. Hence, future research should consider utilising multiple sources of data, across different levels of management and over extended time periods. Again, for meaningful generalisations, it is recommended that future studies replicate our findings in diverse countries and organisational contexts, enhancing the broader understanding and applicability of the results.

Lastly, despite the widespread influence of globalisation, which has underscored the importance of employees, there has been a noticeable shift towards cultivating conducive, inclusive and collaborative work environments within the realm of management research. Keeping this contextual evolution in mind, our findings and identified factors have yielded invaluable insights into the complexities of contemporary organisational dynamics. By shedding light on the intricate interplay of variables and phenomena across diverse organisational contexts, our research endeavours have made significant contributions to the existing knowledge base in these fields. Looking ahead, future studies present an opportunity to explore the potential influence of additional contextual factors on various organisations. For instance, research could delve into the impact of HRM strategies such as sustainable HRM [154], as well as explore the effects of EVB (promotive & prohibitive) [155] and outcomes like team performance, employee satisfaction, and retention.

Funding

The author(s) declared no funding support for this study.

Ethics statement

All the procedures performed in this study involving data collection were in accordance with the ethical standards of all the participating telecommunication companies.

Informed consent

Informed consent was obtained from all individual participant included in this study.

Data availability statement

The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.

CRediT authorship contribution statement

Akinjide F. Badru: Writing – original draft, Software, Methodology, Conceptualization. Georgiana Karadas: Writing – review & editing, Supervision, Conceptualization. Olusegun A. Olugbade: Writing – review & editing, Supervision, Conceptualization. Souad Hassanie: Software, Methodology, Conceptualization.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Appendix A. Supplementary data

The following is the Supplementary data to this article: