Psychological Capital Protects Social Workers from Burnout and Secondary Traumatic Stress

: Summary: To counteract the negative consequences inherent to the emotionally demanding professions like social work, we need to advance the understanding of the resources that preserve the employees’ well-being. This study investigated the role of Psychological Capital (PsyCap) in protecting social workers from developing burnout and Secondary Traumatic Stress (STS). The design of the study builds on the job demands-resources model and the conservation of resources theory. A national sample of 193 Romanian social workers participated in the study. We used the structural equation modeling framework for data analysis. We tested two structural models that had burnout as a mediator for the relationship between PsyCap and STS: A partial mediation model and a total mediation model. Findings: The total mediation model was supported by our data suggesting that PsyCap has a protective role against burnout, and subsequently, STS. Moreover, the results indicate that burnout is the critical link between personal resources and STS. Applications: The results of the study contribute to enhancing the protection of the social workers’ well-being in their professional settings, by advancing the knowledge about the resources that need to be developed in order to prevent or reduce the negative job consequences associated with helping professions. As such, increasing PsyCap levels of employees enhance the sustainability of their working conditions.


Introduction: Occupational Risks Associated with the Social Work Profession
The workforce can be the most valuable resource for an organization. Thus, in organizations preoccupied with fostering healthy and sustainable organizational climates, the care for the well-being of the employees should be of central concern. That is especially important when the employees are the ones that provide care to others, as part of their job.
Social work is a helping profession, designed to provide institutionalized support to persons in the most vulnerable situations, which are often victims of trauma, violence, oppression or discrimination, (like the victims of physical or sexual abuse, victims of human trafficking, refugees and migrants, or neglected children). As such, professional social work activities are strongly client-based, with social workers being involved in complex social situations [1], that require undertaking a variety of roles (from providing guidance, counseling, and support, to mediating and advocating for the clients' best interest) to find the best ways to assist their clients. Their tasks often involve communication and contact with the victims, and sometimes also with their aggressors (i.e., child service workers).
Social workers need to always be in their best shape mentally, physically and emotionally: They have to be knowledgeable, supportive, empathetic, balanced, and also resilient to failure, in order to do their job properly and assist the vulnerable populations that make up their clientele. However, as part of their job requirements, social workers come in contact in their daily activity with explicit information and details about traumatic experiences (rape, abuse, exploitation, neglect) and negative life events (illnesses, accidents, deaths), via clients' accounts or organizational documents, like victims' testimonies or police reports. In these circumstances, it is not difficult to imagine that such intense exposure to pain and trauma, frequent, and for a prolonged period, takes its toll over the years on this category of human service workers.
During the last decades, research increasingly focused on the professional hazards associated with social workers' activity. The host of empirical evidence accumulated so far has provided us with an array of theoretical and conceptual frameworks in analyzing and interpreting the adverse impact of working in helping professions. Among them, the burnout syndrome [2,3], and the secondary traumatization [4,5] stand out in terms of negative consequences over the social worker's well-being [6,7].

Burnout
The burnout syndrome has been recognized as a professional hazard associated with the helping professions, including social work, for a long time now [1,3,[7][8][9][10]. Thus, burnout, as a work-related phenomenon, is characterized by a combination of exhaustion or low energy and cynicism or low identification [11][12][13]. Together, exhaustion and cynicism are called the core parts of burnout and are considered the mental distancing from work [14,15].
Among social workers, burnout stems from working conditions that are described as "common aspects of the social work profession" [7] (p. 89): High caseloads, high levels of bureaucracy, lack of clarity with job roles, daily exposure to emotionally charged situations, and working with few resources and little support. Removing children from their families, acknowledging the effects of prolonged neglect/abuse, or collecting data about the gruesome details of a sexual assault are part of a social worker's daily job. Repeated exposure to such overwhelming situations results in feelings of emotional exhaustion or depersonalization that impede the individual in fulfilling even the most basic personal and professional responsibilities or duties [5,15,16]. Emotional exhaustion refers to feeling depleted of emotional and physical resources [17]. Social workers who are emotionally exhausted will feel overstrained and will not have any more resources to cope with their demanding work in dealing with persons that need support. Cynicism involves a mental detachment from work, often accompanied by a negative and callous perception of colleagues, duties, and clients [18]. Cynical social workers will ignore the disturbing experiences by putting mental distance between them and their clients.
Burnout is associated with the ill-health of persons affected by it and results in emotional, psychological and physical health problems, such as depression, sleep disturbances, headaches, back and neck pains, flu-like illnesses, or gastrointestinal issues [8,10]. It is also inductive of decreased job performance, increased absenteeism, temporary work disability, lower organizational commitment, and high turnover [8,10,19]. Burnout sets in gradually, over time, as the persons deplete their resources and are no longer able to activate their healthy defense mechanisms to tackle it [10,20]. As such, burnout negatively impacts the persons' well-being, job performance and turnover intention [8,21,22].

Secondary Traumatic Stress (STS)
In the last two decades, many studies [5,[23][24][25] have also increasingly acknowledged the psychological and emotional risks social workers face, as a result of their frequent contact with traumatized clients.
The secondary traumatization is related to the professionals' indirect exposure to trauma, through the clients' narratives and accounts of the traumatic events. This can happen when assisting the client in recovering after such an event, which involves listening to details about the traumatic experience and observing its outcomes (i.e., physical or emotional wounds). In time, this exposure has an impact on the helpers' emotions, behaviors, beliefs, and values. Social workers, child protection service workers, military health providers, and general trauma therapists are among the professionals that have the highest risk of developing secondary trauma [6]. One main framework currently used to explain the consequences of indirect exposure to trauma among the professional helpers is secondary traumatic stress (STS) [4], which shows close resemblance to Post-Traumatic Stress Disorder (PTSD) [5,26]. STS is viewed mainly as a psychological reaction to a specific stressor encountered in the work environment-the indirect (secondary) exposure to the traumatic content via contacts with trauma survivors and their stories [6].
STS involves three clusters of symptoms: Intrusion, avoidance, and arousal [26]. A social worker presenting intrusive symptoms will confront undesired re-experiencing of the client's traumatic episode (e.g., thinking or having dreams about the client's trauma). A social worker with avoidance symptoms will evade the stimuli associated with the trauma (e.g., being unable to recall essential details). The arousal symptoms will manifest through increased arousal or anxiety of the social worker (e.g., sleeping difficulties, irritability).
A relatively recent meta-analysis [25] among workers with indirect exposure to trauma (social workers included) indicates the likeliness of co-occurrence of both burnout and secondary traumatization among these professional categories. Because of the symptoms associated with the two conditions, this puts at high risk the mental, emotional and physical health of the employees and impedes the development of sustainable work environments in social work organizations.
In light of the recent advances in pinpointing the professional hazards that affect the occupational well-being of people working in helping professions, an effort to understand how the hazards work and how they can be tackled is imperative for designing sustainable working conditions for human service workers.
Finding the strategies to reduce the occupational risk factors and enhance the influence of the factors that protect workers' health is a necessary step in fostering healthy and sustainable work climates in helping organizations.

Theoretical Frameworks Used in the Current Study
The current study draws on two theoretical frameworks: The job demands-resources theory (JD-R) [27], and the conservation of resources theory (COR) [28]. Firstly, the JD-R theory posits that any profession can be characterized by a series of job demands and job resources. The job demands are those physical, social, or organizational requirements of the profession regarding the physical or mental effort that has to be put in exercising it, and which in turn entails certain physiological and psychological costs for the worker [29]. In turn, the job resources are those physical, psychological, social, or organizational dimensions of the job that ensure the achievement of the work goals, reduce the physiological and psychological costs associated with the job demands and stimulate the worker's growth and development [29]. The value of this framework for the current endeavor is that it explains the negative professional outcomes like burnout through an imbalance between the two dimensions of the job (demands and resources): Such negative outcomes appear when job demands are higher than the job resources needed to cover them [30]. According to this model, burnout acts as a mediator between job demands and employee health and well-being, through the gradual draining of mental resources [31]. In turn, job resources are seen as instrumental in achieving work goals by stimulating a fulfilling, positive work-related state of mind, and fostering work engagement [31]. Additionally, research undertaken under the JD-R framework showed that personal resources mediate the relation between job characteristics and well-being and are positively related to work engagement [31][32][33].
Secondly, the COR theory [28] emphasizes further the importance of resources in tackling the individual stressful situations (including those at the workplace). COR theory is a basic motivational theory which posits that when this basic motivation is threatened or denied, stress ensues [34]. Applied as a theoretical model, it helps explain the etiology of burnout and the processes that are likely to accompany work-related stress. In terms of practical applications to the work environment, it suggests that interventions to prevent or reduce work-related stress should be based on enhancing resources and eliminating vulnerability to resource loss [34].
The use of this framework for the current paper is that it allows us to approach the workers' efforts in dealing with the job stressors through the lens of two opposite mechanisms ('spirals') that impact their resources: A 'gain spiral'-when the workers act toward protecting the resources already acquired and put them at using for gaining new ones, and a 'loss spiral', that ultimately affects the employees' well-being by depleting their resources. The 'gain spiral' is compatible with the JD-R perspective on the relationship between personal resources, well-being and work engagement and was supported empirically by studies drawing from both models [32,33].
On the other hand, the model of the loss spiral could explain in theory the co-occurrence of burnout and secondary traumatization among some human service workers noticed by a recent meta-analysis [25] as concurrent outcomes of a process of individual resource depletion. Additionally, the primacy of the resource loss principle of this theory states that resource loss is more harmful to individuals compared to resources gain. Its translation would be that for an individual, it is more harmful to lose a certain quantity from a specific type of job resource that it would be useful to gain the same quantity. As such, at the individual level, the 'loss spiral' would be more salient than the 'gain spiral'.

PsyCap as a Personal Resource Against Burnout and STS
Several studies have been focusing on the resources that could counteract the adverse effects of emotionally demanding professions, like social work [35][36][37]. The results showed that personal resources are essential in equipping professionals to handle their job demands properly and in protecting their well-being [36][37][38]. As such, personal resources have a significant role in enabling social workers to cope with their professional demands.
Among this category of resources, psychological capital (PsyCap) is increasingly held in high regard in preserving the well-being of employees [39,40]. PsyCap is a construct that emerged within the Positive Organizational Behavior (POB) practices. Anchored within the positive psychology framework, the POB is defined as "the study and application of positively oriented human resources strengths and psychological capacities that can be measured, developed, and effectively managed for performance improvement in today's workplace" [41] (p. 59). For a psychological construct to be included in POB, it has to meet several requirements: To be theory-and evidence-based; to be positively-oriented; to be validly and reliably measurable; to be open to development and management; and to be related to desired and measurable work attitudes, behaviors and performance criteria [42]. Four such constructs have been deemed to answer all these requirements [42]: Hope, efficacy, resilience, and optimism. PsyCap integrates the four positive psychological resources that best fit the POB inclusion criteria, as a higher-order core construct based on the shared commonalities of the four first-order constructs and their unique characteristics [42]. PsyCap is conceptualized as a positive psychological state of development encapsulating hope, self-efficacy, optimism, and resilience [42,43].
Hope depicts the positive state in which the individuals are motivated to achieve an objective and developing realistic plans regarding this objective, despite the possible troubles they may encounter on the way [44,45]. This dimension conveys the will (motivation to achieve the desired objective) and the path (the capacity to elaborate a fitting plan and follow it accordingly) of the individual. Consequently, social workers with a high level of hope will easily set intervention objectives and design the solutions needed to reach their targets. Self-efficacy refers to the individuals' conviction in their capacity to execute or carry out specific tasks in given contexts, by streaming the necessary courses of action and mobilizing motivational and cognitive resources [46,47]. Social workers with high self-efficacy levels will have elevated confidence in their capacities to engage in sorting out their clients' complex social problems. Optimism labels the general anticipation of desirable outcomes. Under this expectancy framework [48], optimistic social workers will presume a positive outcome when confronted with uncertainty about their actions. Resilience represents the individuals' capacity to recover after adverse events. To accommodate adaptation to such changes and further achieve high performance, resilient individuals will entail a combination of flexibility, acceptance of reality, and perception of life as meaningful [38]. Resilient social workers will prevail through difficult situations (like the failure of an intervention, stressful job demands, or the interaction with a person that experienced traumatic stress) and will continue to perform at a high level in the tasks that follow the event.
PsyCap is a malleable concept, and based on POB practice, its sub-components can be enhanced through organizational interventions [49,50].

The Results of Previous Studies on the Interplay between PsyCap, Burnout and STS
A study dedicated to the analysis of the relationship between PsyCap and job stress [51] found a significant negative relationship between the two variables. A literature review on the role of resilience, one of the PsyCap dimensions, in responding to workplace adversity suggested that active participation of employees in the development and strengthening of their resilience contributes to reducing their vulnerability to workplace adversity [52].
The processual perspective on burnout (it sets in gradually, over time, as the person depletes the mechanisms or resources needed to tackle their job demands) makes it compatible with the JD-R theory [27]. It, thus, opens up new opportunities in approaching the topic and especially in designing effective intervention programs. Based on the JD-R theory, personal resources (i.e., self-efficacy and self-esteem) have a protective impact on employees' well-being, making them more resistant to developing burnout [53]. This was confirmed by a variety of empirical studies that assessed the relationship between PsyCap and burnout among different professional categories [54][55][56][57][58].
The results of a study on Chinese nurses showed that, through the partial mediation of organizational commitment, PsyCap could decrease job burnout [59]. Similar results about the correlation between PsyCap and burnout were also obtained on different samples in Romania (e.g., IT sample) [60].
A meta-analysis of previous research [25] showed that burnout and STS are strongly correlated among individuals who are exposed to indirect trauma through their job. Also, a recent examination of the relationships between burnout and STS among human services workers [6] showed a unidirectional path, from burnout to STS, with the former being a potential 'gateway' outcome, which can trigger the development of the latter [6] (p. 11).
The relationship between PsyCap and STS has received less attention so far. One study assessing the influence of PsyCap on adaptation to traumatic stressors among soldiers in combat (exposed directly to traumatic events) showed the significant role of PsyCap in coping when demands are most potentially overwhelming [61]. Moreover, a recent study on nurses that work in acute care settings found that PsyCap is negatively related to compassion fatigue, and this relationship is moderate to strong [62]. However, the components of PsyCap have been investigated separately in relationship with trauma or STS, and the studies yielded encouraging results.
A recent study investigated the relationship between the sense of self-efficacy and traumatic symptoms among mental health professionals working in communities exposed to high levels of trauma. Finklestein and his colleagues [63] showed that self-efficacy was negatively correlated with trauma symptoms.
In various studies investigating the relationship between resilience and negative job consequences among human service professionals, higher levels of resilience were found to be a significant predictor of low levels of STS [50,64,65]. Similar results were obtained in a study involving a sample of doctors, where resilience was negatively associated with burnout and secondary traumatic stress [66].
An investigation of predictors of traumatic exposure and PTSD symptoms among a sample of students reported that individuals with higher dispositional optimism have a lower risk for developing PTSD symptoms after exposure to trauma [67]. A meta-analytic review of 103 studies examining the role of optimism and other factors in contributing to posttraumatic growth found that optimism was moderately related to posttraumatic growth [68].

Objectives of the Current Study
The current literature shows that social work activity is a fertile ground for the development of concurrent occupational risks that have negative consequences on the workers' state of health. Burnout and STS are among the most significant risks. However, the sequences of development for the two concurrent outcomes has not been established yet, nor has the mechanisms through which the two constructs generate or reinforce each other. At the same time, PsyCap was linked to well-being (e.g., work happiness and work engagement) in various empirical studies [39,40,69], and promises real value in tackling the occupational risk factors related to human services professions, like social work.
According to the JD-R theory, and the results of the empirical research, PsyCap (as a personal resource) could play a role in reducing burnout and other negative outcomes, such as STS [27]. Furthermore, based on the COR theory [28], burnout should develop previously to other negative outcomes that are related to health. For instance, it was found that burnout mediated the relationship between job demands and ill-health [70]. Thus, burnout could be a variable that links personal resources and STS. Moreover, the 'loss spiral' [28] could explain why individuals that a small pool of personal resources have (e.g., PsyCap) are likely to lose them easier. It could also explain the development of burnout and the ensuing occurrence of STS, in the light of the primacy of loss principle.
Thus, in order to design and promote the appropriate measures that can be taken in order to avoid the social workers' personal resources depletion, protect their well-being and develop sustainable working conditions for them, further, exploration is needed on the interplay between the factors that put the workers' well-being at risk (in this case, burnout and STS) and those that have the potential to protect it (like PsyCap).
Such an exploration would need to focus on the relationship between PsyCap, burnout, and STS in order to clarify how this relationship works. The answers could allow us to advance further the knowledge on how social workers can be protected from burnout and STS in their work environment, by discontinuing the 'loss spiral'.
Considering all the above, for the current study, we hypothesized the following:

Participants and Procedure
For the current study, we used a sample of 193 Romanian social workers from a national level. Given the dispersion of the potential subjects and the variety of their profiles, a non-probability sampling method was adopted through rational construction. The selection of the respondents was conducted voluntarily through a public research announcement disseminated through social work organizations around the country.
The participants at the study were asked to fill out an online questionnaire comprising several measurement scales. In the introductory section, the questionnaire stipulated the purpose of the research and presented the intended use of the results. The answers of the participants were anonymous and confidential (they could not be traced back to the identity of the respondents).
The age of social workers participating in the study (87.60% women) varied between 23 and 64 years (M = 39.16, SD = 8.21). The average tenure in the same organization was of approximately 90 months for the entire sample, with an average of eight years for the total tenure in social work. Table 1 summarizes the demographic and professional characteristics of the participants.

Measures
Psychological capital was assessed with the 24-item PsyCap Questionnaire [43]. The PsyCap Questionnaire has previously been validated psychometrically in Romania [51]. The questionnaire comprises four subscales, each with six items: Self-efficacy ("I feel confident presenting information to a group of colleagues"), hope ("There are lots of ways around any problem"), resilience ("I usually take stressful things at work in stride"), and optimism ("I approach this job as if every cloud has a silver lining"). The items were scored on a 6-point scale ("1 = strongly disagree", "6 = strongly agree"). Cronbach's alpha values of the overall PsyCap scale and for each of the subscales were adequate: PsyCap (α = 0.92), self-efficacy (α = 0.90), hope (α = 0.84), resilience (α = 0.72), and optimism (α = 0.77).
Burnout was measured with two (of the three) scales of the Maslach Burnout Inventory-General Survey (MBI-GS) [71]: Emotional exhaustion (five items; "Working all day is really a strain for me"), and cynicism (five items; "I doubt the significance of my work"). The third component of the scale (personal accomplishment or inefficacy) was not included in the investigation because: (1) The first two components are considered to be the core factors of burnout [72][73][74]; and (2) the third component is considered by various authors as rather reflecting the employees' personality and not their reactions to stressful situations [75][76][77]. Furthermore, it is seen as a form of self-evaluation related to performance [78], and thus, has a separate role from exhaustion (a form of strain) and cynicism (a form of defensive coping) in the burnout phenomenon [79]. The MBI-GS has been successfully validated psychometrically in Romania [80].
Secondary traumatic stress was assessed using a Romanian version of the Secondary Traumatic Stress Scale (STSS) [26], which was evaluated using the standard back-translation technique [81]. This instrument has three subscales: Intrusion (five items; "I had disturbing dreams about my work with clients"), avoidance (seven items; "I felt emotionally numb"), and arousal (five items; "I expected something bad to happen"). All the items were scored on a 5-point scale ("1 = never", "5 = very often"). The reliabilities tests suggest an acceptable internal consistency for the overall STS scale (α = 0.94) and also for its components: Intrusion (α = 0.79), avoidance (α = 0.89), and arousal (α = 0.88).

Data Analysis
The data was analyzed based on the structural equation modeling (SEM) framework [82], using MPlus software [83]. Several of the variables had non-normal distributions. Therefore, the model fit was assessed by using 5000 bootstrap samples with 95% confidence intervals [84]. Three absolute fit indices were used: Chi-square statistic, root mean square error of approximation (RMSEA), and standardized root mean square residual (SRMR) and two relative fit indices: Tucker-Lewis index (TLI) and the comparative fit index (CFI). The standards for the fit indices were the following: RMSEA < 0.06; SRMR < 0.08; TLI and CFI > 0.95 [85]. We did not use the root mean square error of approximation (RMSEA) to assess model fit because of its tendency to provide false negative results for models with very few degrees of freedom [86]. Moreover, the indirect effects were evaluated using 5000 bootstrap samples with 95% confidence intervals.
Thus, the latent factor PsyCap was compound by the four components, self-efficacy, resilience, hope, and optimism; burnout was compound by the two components, emotional exhaustion, and cynicism; STS consisted of three observed dimensions, intrusion, avoidance, and arousal.
Firstly, we tested two measurement models to assess the common method bias using Hartman's single factor [87]. Thus, we examined the three-factor model (M1; each latent variable is considered a factor) and a single factor model (M2; Harman's single-factor) to test the common method variance. Secondly, we tested the structural models: The hypothesized model, partial mediation model (M3), and the alternative one, a total mediation model (M4). Table 2 presents the descriptive statistics, the correlation matrix, and the reliabilities for all the observed variables. All the Cronbach's α coefficients indicate acceptable reliability, and all the correlations are statistically significant.

Measurement and Structural Models
We conducted a confirmatory factor analysis (CFA) before testing the hypotheses. The analysis suggested that the three-factor model (M1) had an acceptable fit, and the single factor model (M2) had poor fit indices. Thus, the three-factor model had better fit indices, compared with the single factor model (∆χ2 (2) = 262.57, p < 0.001). The next step was to test the structural models. The two models, the hypothesized (M3; partial mediation model) and the alternative model (M4; totally mediated model), had a good fit, but the association between PsyCap and STS was not significant (β = 0.44, p = 0.507). Therefore, the appropriate model was the totally mediated model (M4) that has similar results with the three-factor model from measurement models (see Table 3). Our data support Hypothesis 1 and 2. Figure 1 details the relationships between the three latent variables: PsyCap was negatively related to burnout (β = −0.67, p < 0.001) and burnout was positively related to STS (β = 0.77, p < 0.001). However, Hypothesis 3 was not sustained by our data, with burnout totally mediating the relationship between PsyCap and STS (−0.

Discussion
This study aimed to examine the relationship between PsyCap, burnout, and STS among Romanian social workers.
We sought to understand the way in which personal resources (PsyCap) and occupational risks (burnout and STS) interact with each other, in the professional realm, by protecting the workers' well-being or placing it at risk.
In doing so, we used as a backdrop the JD-R model and the COR theory, which help illuminate some of the mechanisms that account for the interplay between the three variables.
The results regarding the hypothesized relationship between PsyCap and burnout (H1), showed that, indeed, these two variables were negatively correlated within the research sample. Previous scholars found evidence for this relationship, on samples of nurses [55,59], but also on IT employees [60]. In light of the JD-R model, PsyCap, as a personal resource of the social workers in the sample, proves a protective role against burnout, traditionally associated with the job demands in human services. Thus, social workers with high levels of hope, optimism, resilience, and self-efficacy tend to feel less emotionally exhausted and less cynical about their work. In this case, we could say that PsyCap (with its four components) acts as a reservoir of energy, that the social workers can use when dealing with stressful job demands.
The results regarding the hypothesized relationship between burnout and STS (H2) showed a positive association between the two variables. This tendency of negative job consequences to associate can be explained under the framework of COR theory [28], which advances that, once a process of resource loss is installed, it engages even more resource loss.
Thus, a social worker with low levels of self-efficacy, optimism, resilience, and hope has a greater risk of developing burnout, and because of that, will be prone to develop further negative manifestations, such as STS. This phenomenon is explained by the primacy of loss principle, which stipulates that the 'loss spiral' is more salient than the 'gaining spiral' [28].
The results regarding the hypothesized relationship between PsyCap and STS (H3 and H4), showed that the data supported a total mediation model. This would make burnout a link between personal resources and STS, meaning it contributes to aggravating the condition of the social workers affected by it. At the same time, the good news is that, in this study, PsyCap shows a protective role in developing burnout, and subsequently, STS. This finding is also supported by both theoretical frameworks used in the current study.
In the light of the JD-R model, burnout mediates the relationship between the high job demands (which lead to the gradual draining of resources) and the employee health and well-being. In exchange, the job and personal resources are instrumental in achieving work goals by stimulating a positive work-related state of mind and fostering work engagement. PsyCap, as a personal resource, helps the employees maintain their engagement with the job and keep the balance between demands and resources. Thus, high levels of PsyCap among social workers (meaning increased levels of self-efficacy, resilience, optimism and hope) act as barriers for job demands, and thus, protect them from developing burnout and STS.
From the perspective of the COR theory, increasing PsyCap levels of social workers would result in decreasing their vulnerability to occupational hazards. The interventions meant to protect the employees' well-being by preventing or reducing work-related stress should be based on enhancing resources and eliminating vulnerability to resource loss: A reservoir of personal resources slows down the 'loss spiral', and thus, prevents the installation of burnout, and respectively, STS in social workers. This process results in improving the sustainability of their working conditions.

Implications for Social Work Practice
The results of the study could contribute to enhancing the protection of the social workers' well-being in their professional settings, by advancing the knowledge about (1) the interplay between the negative consequences resulting from the inherent job demands, and (2) the resources that need to be developed in order to prevent or reduce these consequences.
The results regarding the positive association between burnout and STS and their interplay in engaging the employee in a salient 'loss spiral', that ultimately results in the depletion of resources, stress the importance of implementing support programs. Those programs should monitor the social workers' well-being and intervene when negative manifestations are signaled, to discontinue the negative spiral's trajectory. Such programs can combine preventive and assistive actions, including supervision, training, mentoring, or coaching. The training of social workers in detecting the signs and symptoms of negative manifestations can happen gradually, starting with their initial training period. Since the results of the study suggest that burnout installs before STS, a periodical (i.e., monthly) screening for burnout signs would help prioritize and focus the intervention, and at the same time, will prevent the installation of STS.
Over the years, organizational development has mainly been focused on increasing employee performance and engagement. However, with the more recent concern with the importance of forging sustainable organizations, the preoccupation shifted also to the well-being of the employees [88].
A key finding of this study is that PsyCap proves a consistent personal resource that can be modelled into bringing important contributions to the well-being of the social workers. From a practical perspective, PsyCap can be used in interventions to reduce burnout and STS.
As such, since PsyCap is a malleable resource that is prone to improvement and development [89,90], responsible social service administrators and managers could invest in the development of their employees' PsyCap, if preoccupied with the sustainability of their social work organizations. Such investments could bring valuable returns, both for the organization and for the employees, as shown by previous studies. [89,91,92].
Studies dedicated to PsyCap Interventions [89,93] (PCI) proved that they produce positive effects both when delivered face-to-face, and in a web-based format. A strategy that targets interdisciplinary teams formed with social workers could benefit directly from the PCI as they interact to resolve the difficult situation of their clients. Additionally, a recent meta-analysis on the efficacy of organizational interventions addressed to increasing PsyCap levels found that there is no single solution in achieving this goal, but there are several approaches that can be effective, depending on the targeted component: While positive psychology interventions were found to have an effect on self-efficacy and hope, and stress management programs had an effect on self-efficacy, PCI were found to have an effect on PsyCap overall [50].

Limitations and Future Studies
The cross-sectional design of this study allowed us only to suggest causal relationships and not to make causal inferences. Longitudinal and experimental designs could be performed to test the causal relationships between the three variables. For example, future studies could test the effectiveness of PCI in preventing burnout and STS among social workers. Secondly, all the variables were simultaneously assessed and based on self-reports, a situation that could lead to common method bias. Another possible limit arises from the method used to test the relationships between the variables (SEM framework). We tested the general relationships by employing only the global constructs (e.g., STS as a composite of three dimensions: Intrusion, avoidance, and arousal). Thus, within the future similar studies, a deeper investigation into the effect of each dimension on the omnibus concept could bring additional information that would help advance even further the knowledge on the use and influence of each dimension.
We encourage future researchers to replicate the hypothetical and the alternative model on other samples or in other locations, as we did not find support for the expected direct relationship between PsyCap and STS. Also, other resources could be added as antecedents in the final model, such as job resources (e.g., autonomy, feedback, or social support) to test the additional effect besides the one from the personal resources.

Conclusions
The current study widens previous research about the occupational hazards associated with helping professions and provides insights on tackling burnout and STS, and thus, reduce the strain they place on the well-being of the employees.
Based on the study findings, burnout and STS, as job related negative outcomes, tend to associate and engage the social workers in the 'loss spiral'. This spiral is characterized by resource depletion and has negative psychological, emotional and physical consequences for the employees.
A key finding of this study is the protective role that PsyCap proves against burnout and STS. As such, PsyCap could be modeled into bringing important contributions to the well-being of the employees in helping professions, by enriching their resources, protecting them from occupational hazards, and thus, developing sustainable working conditions for them.