2.1. Internal Marketing

Organisations are currently aware that internal marketing is an essential concept, both in terms of its philosophy and its practice as a marketing tool (^{Rodrigues et al., 2018}). Internal marketing is a fundamental tool for all organisations (^{Ahmed & Rafiq, 2002}). The internal marketing concept initially derived from a concern to improve the excellence of (internal) service provided by employees (^{Qiu et al., 2021}). In the early phase of the development of internal marketing, most research focused on employee satisfaction and analysed the role of internal marketing in improving service quality (Ahmed & Rafiq, 2002, Rafiq & Ahmed, 2000). Since these early conceptualizations of internal marketing, research in this area has advanced considerably (Qiu et al., 2021). However, as the authors stated, there is no consistent way of defining and conceptualizing internal marketing. According to ^{Grönroos (2001}), internal marketing focuses on forming internal relationships among the employees of an organization regardless of their position. It allows for the introduction of a communication that can satisfy the needs of the employees. It became clear that an organization that employs internal marketing practices can better benefit employees, encouraging them to achieve better results (^{Huang & Rundle-Thiele, 2014}).

Internal marketing is therefore regarded as a fundamental tool, whose primary purpose is the existence of an organization focused on the internal customer that aims to encourage its employees and allow them to achieve the organization's goals. ^{Sohail and Jang (2017}) consider that internal marketing is a vital instrument for improving work processes, interpersonal relations, information flow, employee training and development, and their connection with the organisation, and whose aim is the achievement of an effective and efficient employee management (internal customers) within organisations. Employees at all levels of the organization can be motivated, mobilized, co-opted, and managed through the use of marketing, human resource management, and related theories, techniques, and principles in order to continuously improve the service provided to external customers and to each other, which is what internal marketing is all about (^{King, 1991}). In this study, internal marketing is viewed as a management philosophy that values the organization’s human resources. This philosophy encourages the engagement, mobilization and supervision of organisational members to promote customer-focused values (both internal and external) and support the implementation of organisational changes (^{Rodrigues et al., 2016}).

^{Jou et al. (2008}) perceive internal marketing as a concept that helped arouse the interest of academics in both marketing and human resource management. The authors developed a scale to measure internal marketing that comprises six factors: empathy and consideration (paying attention to employees personal needs), benchmarking (what competitors have to offer to their employees), job quality (the financial and emotional values associated with the employees’ job), upward communication (the opportunity for employees to communicate their dissatisfactions or suggestions to their managers), information sharing (strategy used by managers to convey organisational messages, missions and values to their subordinates), and promotional activities (whether the company engages in promotional or public relation activities).

Several investigations have examined the consequences of implementing the concept of internal marketing. As ^{Qiu et al. (2021}, p. 7) point out, “Considerable qualitative and quantitative work in the internal marketing stream confirms various employee-attitudinal benefits from internal marketing implementation”. For example, ^{Jou et al. (2008}) sustain that internal marketing is associated with job satisfaction, customer behaviour, organisational support, organisational commitment, and work group socialization, which induces a change in customer satisfaction. ^{Kesen et al. (2017}) studied the effects of internal marketing on organisational trust in the hotel industry, and confirmed that internal marketing affects trust in the organization. The results obtained from the study offer promising outcomes for the organization, when implemented appropriately (^{Qaisar & Muhamad, 2021}); however, as far as we know, the principles of internal marketing have not been actively applied within the local public sector environment. Qaisar and Muhamad (2021), for instance, argue that there is a lack of research on the role of organisational characteristics in internal marketing.

Based on the literature review, the following model is proposed (Figure 1). It consists of five variables and nine hypotheses. The model analyses the effects of internal marketing on certain employees’ attitudes and behaviours. The independent variable is internal marketing and the final dependent variable is job performance. This model assumes that the job satisfaction, organisational commitment, and organisational trust (indicative of the internal relationship quality) variables are influenced by internal marketing and impact job performance. Theoretically this study employs Social Exchange Theory (SET) (^{Blau, 1964}; ^{Cropanzano et al., 2017}) to explore the relationship between internal marketing, job satisfaction, organisational commitment, organisational trust and job performance. This theory outlines the reasons why employees decide to commit more or less to their job, depending on their perception of the support, rewards, and cost of the relationship, which will determine whether or not they will choose to maintain this social interaction and put in their best efforts (^{Ohemeng et al., 2019}).

In this model, the use of internal marketing is seen as a way to foster good relationships between local public sector organisations and their employees. It is believed that these relationships are reflected in the employees’ positive attitudes and behaviours and influence their satisfaction, commitment, trust in the organisation, and job performance. Along with satisfaction, trust and commitment, which are recognised as key relational mediators, are of great importance in the field of relationship marketing and are central to the relational mediators model of relationship marketing (^{Morgan & Hunt, 1994}; ^{Brown et al., 2019}). In the internal context, this model applies relationship quality theories to internal relationships, defining internal relationship quality as the result of various positive connections between the organisation and its employees (^{Li et al., 2021}). As such, job satisfaction, organisational commitment and organisational trust are seen as indicators of internal relationship quality.

The hypotheses of the conceptual model are discussed in the following section.

Figure 1 Proposed conceptual model. Source: Own elaboration. 

2.2 Internal marketing and job satisfaction

Satisfaction is essential for the survival of any private or public organization (^{Nicholls et al., 1988}). An organization that is concerned with its employees' satisfaction and invests in their training helps them perform better, and this sort of performance will trigger an increase in operational performance (^{Kaur et al., 2009}). ^{Hoppock (1935}, p. 47) defines job satisfaction as "a combination of psychological, physiological, and environmental factors that cause a person to state 'I am satisfied with my work'". In turn, ^{Locke (1976}, p.1300) defines it as "a pleasant or positive emotional state resulting from an appreciation [perception] concerning a work experience". In turn, ^{Vroom (1964}) defines job satisfaction as “affective orientations on the part of individuals towards work roles which they are currently occupying”.

Although the definitions of job satisfaction may vary, they all refer to an emotional attitude that people acquire from their work. Job satisfaction is a pleasurable emotional state that comes from some work or experiences at work (^{Locke, 1976}); it is associated with the employees’ perception of justice, fairness and respect (^{Rego, 2001}) and portrays a positive way in which each individual analyses and appreciates his/her work (^{Kreitner & Kinicki, 2004}). Therefore, job satisfaction is characterized as a set of unfavourable or favourable feelings that shape employees’ perception of their work (^{Mathieu et al., 2014}).

An increasing amount of literature has been emphasizing the value of employee job satisfaction, as the competition between business activities or the effectiveness of employee behaviours has been receiving more and more attention from both scholars and practitioners (^{Cheng, 2020}). According to the author, research work focusing on organisational behaviour, human resources, and strategic management has paid much attention to employee job satisfaction, and has suggested that it can play a major role in human resource or organisational psychology. ^{Lee et al. (2012}) consider that organisations have shown increasing scientific interest in job satisfaction, given that it can positively influence job performance, and is bound to become an essential tool in improving productivity and the quality of services provided.

It is reasonable to conclude that internal marketing is a significant factor in influencing job-related attitudes, given the social and organisational support available in an environment that uses internal marketing practices. Hence, this study seeks to test the impact that internal marketing has on job satisfaction among employees of local public organisations. Several studies have already confirmed the positive relationship between the two concepts, but the quantity of studies focusing on local public institutions is still scarce. For example, ^{Iliopoulos and Priporas (2011}) conducted an investigation in Greek public hospitals and concluded that internal marketing had a considerable positive effect on job satisfaction in healthcare. In a study conducted among the employees of utility municipal firms, ^{Ružić et al. (2015}) highlight the strong impact of the application of internal marketing on employee motivation and job satisfaction. In the public medical sector, ^{Sun et al. (2020}) discovered that internal marketing represents a valuable competitive advantage and that it is a consequence of internal customer satisfaction and internal service quality. Likewise, in a study focusing on social and healthcare organisations, ^{Rodrigues et al. (2016}) confirmed that internal marketing practices have a positive effect on job satisfaction.

In other sectors (tourism industry), ^{Huang and Rundle-Thiele (2014}) demonstrated that hospitality employees' job satisfaction improved when practices such as internal communication and training are implemented, and that this new-found satisfaction had a positive impact on their job performance. A similar result was obtained by ^{Mainardes et al. (2019}) who concluded that internal marketing positively influences employee satisfaction in the banking sector. In a study applied to employees of three different services industries (healthcare, banking-finance, and insurance organisations), ^{Taştan and Davoudi (2020}) confirmed that employees who have a favourable perception about their organisation's internal marketing activities will feel greater job satisfaction and, consequently, will perform better in their work roles.

Accordingly, the following hypothesis is proposed:

H1 - Internal marketing positively and directly influences job satisfaction.

2.3 Internal marketing and organisational commitment

Considerable attention has been directed towards organisational commitment from scholars and practitioners alike (^{Breitsohl & Ruhle, 2013}). The impact of organisational commitment on organisational behaviour is undeniable. Organisational commitment is often recognized as an intervening factor in employees' attitudes and behaviours (^{Rodrigues et al., 2016}; ^{Chiu et al., 2020}). Organisational commitment is defined as a psychological state described by the relationship between the employee and the organization and that has an effect on the employees’ decision to maintain membership in the organisation or to leave the organization (^{Mowday et al., 1979}). Committed employees are more supportive and adherent to the company’s goals, more loyal to the company, and exhibit a lower desire to quit (^{Abdelazimahmed et al., 2022}). For ^{Meyer and Allen (1991}), organisational commitment is a psychological and physical bond between an employee and an organization. The multidimensional model of organisational commitment proposed by Meyer and Allen (1991) includes three components: affective commitment, continuance commitment and normative commitment. This research will only study and analyse the affective component. In this conceptualization, affective commitment refers to the employees’ strong emotional attachment to, identification with, and involvement in, a given organization. Employees who are affectively committed to the organization have built strong personal relationships with it and desire to remain in that organisation (^{Agarwal & Sajid, 2017}). This concept encompasses the psychological attachment between a worker and his/her employer, and can be characterized as an energy that fosters the union between all employees, allowing them to work as a team to achieve the organization's goals (Rodrigues et al., 2016).

The present study considers that there is a relationship between internal marketing and organisational commitment. ^{Allen and Meyer (1990}) assert that the most influential factor in determining affective commitment are work experience antecedents that fulfil the employees' psychological need to feel comfortable within the organisation and competent in the work-role. We suggest that internal marketing could be a strong tool to achieve this goal.

Prior research has established that internal marketing is associated with organisational commitment. For example, ^{Mero et al. (2020}) confirms that the implementation of internal marketing strategies and activities strengthens employee organisational commitment in Ecuadorian co-operatives. In their study, ^{Chiu et al. (2020}) found out that the implementation of internal marketing increases organisational commitment, which will, in turn, improve job performance. Furthermore, organisational commitment partially mediates the relationship between internal marketing and job performance. ^{Rodrigues et al. (2016}) also confirm that internal marketing constitutes an important tool to increase employee organisational commitment. Similarly, when they looked at the public banking industry in India, ^{Thomas and Rodrigues (2020}) conclude that employees who are provided with internal marketing practices that include respectful treatment, favourable working conditions, independence in their work roles, and well-defined responsibilities, are more likely to be more committed to their banks and to the tasks they are asked to perform.

Based on the above discussion, the following hypothesis is presented:

H2 - Internal marketing positively and directly influences organisational commitment.

2.4 Internal marketing and organisational trust

The importance of trust to psychosocial functioning has been advocated since the beginning of contemporary psychology (^{Rotenberg, 2010}). For Simpson (2007), trust is one of the most important components for the development and preservation of happy and well-functioning interpersonal relationships. Trust is also foundational to daily interpersonal relationships (^{Rempel et al., 1985}), even between groups within companies (^{Dirks & Ferrin, 2001}).

Trust is fundamental to the development and survival of organisations and interpersonal relationships (^{Zanini, 2007}). Building trust among people in organisations is vital for efficiency (^{Thompson, 1967}). If we have trust, we will act in the best possible way to fulfil our goals and, in turn, those of the organization. This implies that we will execute better when performing our duties. Trust is enhanced when the parties have good communication and when one seeks to prevent opportunistic actions that cause damage to one of the parties (^{Morgan & Hunt, 1994}).

Most concepts involving trust share some common factors: trust helps overcome risk and hesitation in exchange relationships, and it emerges in situations that threatens the stability of a relationship. This situation usually occurs when one of the parties involved does not fully understand the motivations and interventions of the other party (^{Moreira & Lopes, 2005}). At the organisational level, trust can lead to increased cooperation, sharing of sensitive information, and to a better performance of the trustor (^{Mayer & Davis, 1999}; ^{Dirks & Ferrin, 2001}). For ^{Cumming and Bromeily (1996}), trust is an individual’s belief, or a belief shared by a group, that another individual or group is honest according to his/her notion of trustworthiness. The authors also state that organisational trust is the conviction that the organisation will behave in accordance with its commitments, both explicit or implicit (Cumming & Bromeily, 1996).

While the associations between internal marketing, job satisfaction, organisational commitment, and job performance have already been empirically demonstrated in the literature (for example, ^{Huang & Kundle-Thiele, 2014}; ^{Rodrigues et al., 2016}; ^{Iliopoulos & Priporas, 2011}; ^{Thomas & Rodrigues, 2020}), the study of the relationship between internal marketing and organisational trust is one of the original aspects of this study since, to our knowledge, this is the first time that a research work focuses on studying the impact of this relationship on the Portuguese local public sector.

To the best of our knowledge, the relationship between internal marketing and organisational trust in the local public sector remains understudied. However, some studies focusing on other sectors have found a positive relationship between internal marketing and organisational trust (^{Kesen et al., 2017}). ^{Órfão (2010}) found out that internal marketing has a beneficial effect on employees' perception of trust. Additionally, they stress that the internal marketing strategies employed by the organization give employees a greater sense of security, as they foster a more open and communicative atmosphere. ^{Hsieh and Wang (2016}) examine the influences of internal marketing on perceived organisational support, employee organisational trust, and employee work engagement in the hotel industry. Their study concluded that internal marketing was positively related to employee work engagement, and that this relationship was partially mediated by employee organisational trust and perceived organisational support; the latter was also found to partially mediate the relationship between internal marketing and employee organisational trust.^{Rasool et al. (2019}) investigated the link between internal marketing practices and the attitudinal behaviour of frontline employees of the banking sector, and concluded that internal marketing is an effective way to improve employee engagement and build organisational trust. ^{Fangue et al. (2020}) investigated the impact of internal marketing on customer trust, both at the organisational and interpersonal levels, in micro finance institutions. Their study focused on external customers, but they also discovered that there is a positive correlation between internal marketing and both dimensions of trust.

Considering the above:

H3 - Internal marketing positively and directly influences organisational trust.

2.5 Internal marketing and job performance

To ensure continued organisational success, organisations are increasingly placing greater emphasis on job performance (^{Gruman & Saks, 2011}). ^{Goffman (1959}, p. 15) defines performance as "an activity of an actor in action, serving to influence the course of that action." This statement is entirely connected to the concept of performance appraisal, and is essential to discern whether a performance is good or not. Performance appraisal has a necessary function in the organisational environment. It is connected to the employees and to the company members, to the way they structure themselves, and to the investment made so they can improve, namely at the level of their skills and abilities. Therefore, the appraisal process, when correctly conducted, can become an ally for the employees and organisations, since they will be able to recognise the potentialities and weaknesses not only of the employees, but also of the evaluators, and of the organization (^{Cappelli & Tavis, 2016}).

^{Taştan and Davoudi (2020}) argue that the impact of internal marketing activities on employees' job performance has been assessed in multiple industries and countries. There are some studies that demonstrate the direct impact of internal marketing on employee performance and the consequences it entails for the organisational level. Some of the more recent studies that managed to prove this correlation include the studies conducted by ^{Imani et al. (2020}), ^{Abidin and Roslin (2019}), and Taştan and Davoudi (2020). The results showed that employees who have a favourable perception on the internal marketing initiatives implemented by their organisation will experience higher job satisfaction and consequently, will have greater performance in their work roles (^{Taştan & Davoudi, 2020}).

Alternatively, ^{Rodrigues et al. (2016}) conducted a study in an organisation providing social and healthcare services, and they concluded that there is not a direct relationship between internal marketing and employees’ job performance; however, the interconnection between the implementation of internal marketing and job performance is mediated by job satisfaction and organisational commitment.

Therefore, the following hypothesis is proposed:

H4 - Internal marketing positively and directly influences job performance.

2.6 Job satisfaction, organisational commitment, organisational trust and job performance

Psychology has introduced a plethora of precursors to job performance, such as organisational commitment and job satisfaction (^{Taştan & Davoudi, 2020}). Job satisfaction is an indicator of employees’ contentedness regarding their jobs (^{Unguren & Arslan}) and is important for the survival of any private or public institution (^{Nicholls et al., 1988}). An organisation that is concerned with its employees' satisfaction and invests in their training helps them perform better and this sort of behaviour will, in turn, trigger an increase in operational performance (^{Kaur et al., 2009}). More recent studies also confirm the positive impact that job satisfaction exerts on job performance. For example, Taştan and Davoudi (2020) confirmed that employees who are satisfied are more likely to demonstrate improved performance and to provide service that will satisfy customers.

Furthermore, investigations conducted by ^{Porter et al. (1974}) demonstrate that organisational commitment is not only a predictor of employee retention, but can similarly be a predictor of increased effort and improved performance. The level of commitment an employee has towards the organization is anticipated to enhance their job performance, as those with a strong commitment to the organization “will demonstrate a greater eagerness to strive for its goals and objectives” (^{Kim, 2005}, p.246). Kim (2005) found out that greater job satisfaction and commitment to the organisation correspond to better institutional performance. ^{Rodrigues et al. (2016}) highlight the positive impact of organisational commitment on job performance. The results of the study developed by ^{Chiu et al. (2020}) confirm that organisational commitment has a positive effect on job performance, and partially mediates the relationship between internal marketing and job performance.

Lastly, organisational trust is deemed to be of paramount importance to the scientific community (^{Orfão, 2010}) and is a key factor in the success and efficiency of organisations. Trust between members of an organisation can greatly aid in the optimisation of the performance of the different organisational functions (^{Dirks & Ferrin, 2001}). Órfão's (2010) research confirms the hypothesis that there is a positive correlation between organisational trust and job performance. This has been corroborated by ^{Singh and Desa (2018}) who, in a study conducted among public employees, have established that there is a direct link between organisational trust and job performance, e.g., a higher level of organisational trust is linked to better job performance.

In line with the conceptual background and supported by the review of the literature, the following hypotheses are developed:

H5 - Job satisfaction positively and directly influences job performance.

H6 - Organisational commitment positively and directly influences job performance.

H7 - Organisational trust positively and directly influences job performance.

2.7 Job satisfaction, organisational commitment and organisational trust

Lack of job satisfaction and commitment among their employees have costly consequences for organisations, since their employees are more likely to make more mistakes that will affect their work performance, they will have to face higher absenteeism, more stress and greater turnover intentions (^{Agarwal & Sajid, 2017}). For that reason, studying these concepts and their relationships has become more important than ever. The present model also suggests that there are direct and positive relationships between job satisfaction and organisational commitment. There are some studies that confirm the positive influence of job satisfaction on organisational commitment. For example, ^{Malik et al. (2010}), claim that researchers have established that job satisfaction is the result of immediate emotions related to positive or negative job experiences, whereas commitment to the organization develops over time as the individual forms a more comprehensive understanding of the organization, of its values and expectations, and of his/her own future in it. Therefore, organisational commitment is perceived to be affected by job satisfaction. Malik et al. (2010) conducted a study in public universities of Pakistan, and confirmed that job satisfaction has a significant influence on organisational commitment. In a study that compared public and private sector employees, Agarwal and Sajid (2017) found out that job satisfaction predicts affective and normative commitment more significantly in public sector than in private sector. Another example is the study of ^{Rodrigues et al. (2016}) which also found that the higher the levels of satisfaction (that include the employees’ wage) of professionals providing social and healthcare, the higher their levels of commitment to the organisation they work for.

Finally, this study will empirically test the relationship between commitment and trust. ^{Brown et al. (2019}) argue that research has already demonstrated that trust enhances commitment (e.g., the seminal article about trust and commitment in relationship marketing by ^{Morgan & Hunt, 1994}). However, Brown et al. (2019) decided to re-examin the causality between trust and commitment. The authors have found that the commitment-to-trust model offers a feasible alternative for Morgan and Hunt's (1994) trust-to-commitment model, and that in business-to-business relationships, commitment does definitely influence trust. Drawing from Brown et al. (2019), in this study we will look at organisational trust as a consequence of organisational commitment, that is, we assume that when employees are committed to their organization, it will be easier for them to trust the company. Additionally, when employees are committed to their organization, they tend to invest more in its successes and goals, which further strengthens trust. The reasoning behind this assertion could be related to the type of employment, organisational setting, culture, and environment existing in (local) public sector organisations.

Individuals have various reasons for being committed to organizations (^{Meyer & Allen, 1997}). As already mentioned, in the present study, organizational commitment was measured by the affective dimension that reflects the willingness to remain in the organization (Meyer & Allen, 1997), and refers to a psychological state wherein the employee shares the organization's values and pursues its goals (^{Mowday et al., 1979}).

Public sector organisations are based on “general public values adhered to serving the common good”, so employees with a strong public service motivation are more likely to be satisfied with their positions, as they are given the opportunity to serve the public environment of their organisations (^{Kjeldsen & Hansen, 2018}, p. 28), and are naturally more (affective) committed to their organisations. Also, employees working for public sector organisations enjoy a high level of job security, predetermined pay raises and assured progression (^{Agarwal & Sajid, 2017}). That is why, according to the authors, public sector employees generally exhibit a greater affective and normative commitment to their respective organisations than those who work in the private sector.

In this context, it seems reasonable to assume that, either because of a strong motivation for public service or because of the job security and/or other working conditions provided in this type of organisations, civil servants tend to have an "innate" sense of (affective) organisational commitment. These factors, in our opinion, potentially contribute to the creation of an organisational trust environment. For example, according to social exchange theory (^{Blau, 1964}), employees' attitudes towards job security will have an effect on the amount of trust they put in the organisation.

Considering the above, the following hypotheses are proposed:

H8 - Job satisfaction positively and directly influences organisational commitment.

H9 - Organisational commitment positively and directly influences organisational trust.

4.1. Sample Profile

The sample consists of 565 employees of local public sector organisations aged between 25 and 66 years (M = 48.3, SD = 8.3), predominantly male (57.0%). The majority of the participants have concluded secondary education (43.0%), 37.7% of them have completed primary education and 19.3% hold a higher education degree. The employees participating in the study were working for 5 local public sector organisations in the municipalities of Chaves (38.2%), Montalegre (23.2%), Boticas (14.2%), Vila Pouca de Aguiar (12.4%), and Ribeira de Pena (12.0%). As for the participants’ professional category, operational assistants (50.1%), technical assistants (27.3%), and senior technicians (18.4%) stand out. On average, they have worked in the organization for 21.7 years (Table 2).

4.2 Measurement Model

The items of the scales were grouped into dimensions (constructs) according to the literature consulted. Their factor structure was analysed using Structural Equation Models. The procedures proposed by ^{Hair et al. (2010}) were followed for their validation. The maximum likelihood method was used, assuming that there is a correlation between the different dimensions.

The normality of the data was verified by analysing the symmetry and kurtosis coefficients. The values obtained below 3 (the highest absolute value of symmetry was -2.024 and kurtosis was 2.831) ensure the approximation to multivariate normality, without jeopardizing the quality of the adjustment indexes and parameter estimates (^{Marôco, 2010}).

A first analysis of the overall goodness of fit, reliability, and validity of the instrument revealed the existence of items with low factor loadings and goodness of fit indexes below the reference values, raising some doubts about the validity and reliability of the instrument. Following ^{Hair et al. (2010}), the items with standardized factor loadings below 0.50 were excluded (items with factor loadings between brackets in Table 3). Therefore, 1 item was removed from the job satisfaction scale, three from the organisational commitment scale, two from the organisational trust scale, and two items from the job performance scale.

After the removal of the items, all those that remained have standardized factor loadings above 0.50, thus ensuring the factor validity of each construct, confirming that the specification of the items is correct (^{Marôco, 2010})

Convergent validity was assessed using average variance extracted (AVE) (Table 3). Values greater than or equal to 0.50 are indicators of adequate convergent validity (^{Hair et al., 2010}). All constructs meet this condition, except for the organisational commitment concept, which obtained an AVE value of 0.496. However, since the value obtained was close to 0.5 and the relevance of this construct for the model, it was included in the analysis.

As for reliability (or internal consistency), all constructs showed Composite Reliability values above 0.70 (Table 3), a threshold value indicated by several authors (^{Hair et al., 2010}; ^{Marôco, 2010}) as the minimum value to ensure the construct reliability.

The verification of discriminant validity was performed by comparing the square root of the VME of each pair of dimensions with the correlation coefficients between these dimensions. According to ^{Hair et al. (2010}), if the square root values of the AVE present higher values than the correlations between the dimensions, discriminant validity is guaranteed. The values of correlations and VME presented in Table 4 show that all dimensions meet these conditions, ensuring their discriminant validity.

To assess goodness of fit, the indexes suggested by ^{Hair et al. (2010}) are presented: the value of the Chi-Square statistic and the respective degrees of freedom, the CFI (Comparative Fit Index), and the RMSEA (Root Mean Square Error of Approximation). The Chi-Square test (X2 = 2291.11; degrees of freedom = 892; p < 0.001) is significant. The values of X2/gl ratio = 2.57, CFI = 0.908 and RMSEA = 0.058 (90% CI: 0.055-0.061) guarantee, according to ^{Marôco (2010}) and Hair et al (2010), a suitable goodness of fit of the model. Thus, the reliability and validity of the instruments are ensured, as was the overall quality of the adjusted model.

4.3 Structural model

Structural Equation Model was used to test the structural model, as presented in Table 5. The model showed an adequate goodness of fit with Χ2/gl = 2.57; CFI = 0.908; RMSEA = 0.058 (90% CI: 0.055-0.061). The results included in Table 5 show that internal marketing significantly, and directly, influences job satisfaction (B = 0.618; β = 0.519; p < 0.001), organisational commitment (B = 0.229; β = 0.225; p < 0.001), and organisational trust (B = 0.662; β = 0.433; p < 0.001), but not job performance (B = -0.033; β = -0.034; p = 0.678). The indirect effect of internal marketing on job performance is not statistically significant either (B = 0.058; β = 0.061; p = 0.379).

Job Performance is directly influenced by organisational commitment (B = 0.695; β = 0.750; p < 0.001) and organisational trust (B = 0.266; β = 0.430; p = 0.008), but not by job satisfaction (B = 0.019; β = 0.023; p = 0.750). However, the indirect effect of job satisfaction on job performance, mediated by commitment and trust, is significant (B = 0.190; β = 0.239; p = 0.010).

Job satisfaction has a direct influence on organisational commitment (B = 0.413; β = 0.482; < 0.001), which in turn has a direct influence on organisational trust (B = 0.885; β = 0.591; < 0.001).