Workplace bullying, defined as “repeated actions and practices that are directed against one or more workers, that are unwanted by the target, that may be carried out deliberately or unconsciously, but clearly cause humiliation, offense and distress, and that may interfere with work performance and/or cause an unpleasant working environment” [1, 2], is one of the significant job stressors in the work environments. According to a meta-analysis , about 15% of employees have experienced bullying. Empirical studies in Japan showed that about 9.0–15.5% of employees have experienced bullying during the past six months [4,5,6], which is similar to European countries (9.5% in Scandinavia and 15.7% in other European countries) .
Various health outcomes have been reported as the consequences of workplace bullying . For example, a cross-sectional study of 2194 Japanese civil servants showed that victims who experienced bullying on a weekly basis had 8 times higher risk of psychological distress and 12 times higher risk of post-traumatic stress symptoms compared to non-victims, after adjusting for age, sex, education, chronic disease, occupation, employment status, shift work, overtime working hours during the past month . A two-year prospective cohort study of 543 workers at welfare facilities for the elderly showed that person-related bullying was significantly linked to subsequent psychological and physical stress responses .
Although previous studies have already identified that workplace bullying causes serious mental health problems to the victims, it is not yet fully investigated whether there are moderating factors on the association. To prevent adverse mental health outcomes, identifying moderators is needed. Therefore, this study investigates the moderating effects of individual resources such as personal resilience and coping styles and organizational resources such as worksite social support on the association between workplace bullying and psychological distress in a longitudinal design.
Organizational and individual resources which moderate the association between workplace bullying and mental health
Worksite social support
As one of the organizational resources, worksite social support is a key component of the demand-control-support model, which defined a combination of high job demands, low job control, and low worksite social support as the most stressful situation [10, 11]. Worksite social support usually consists of supervisor support and coworker support and a contributor of buffering psychological distress among workers under stressful working environments such as job strain (a combination of high job demands and low job control). Worksite social support is defined as the degree to which individuals receive supports from supervisors and coworkers. Receiving a good amount of supports from work members prevent workers from developing mental health issues. Besides that, supervisor and coworker support can increase the employee’s comfort in the organization by satisfying needs such as self-esteem, acceptance, and belonging .
Previous research already confirmed a negative relationship between workplace bullying and both supervisor and coworker support [4, 13, 14]. On the other hand, inconsistent results were found in the moderating effects on the relationship between workplace bullying and mental health outcomes. For example, a cross-sectional study of 820 employees from various organizations in Poland has reported that only coworker support moderates the relationship , while another cross-sectional study of 1733 employees in New Zealand reported that both supervisor and coworker support reduced psychological strain among workers who experienced workplace bullying . Although a cross-sectional study of 335 school teachers in Australia reported perceived organizational support moderated the relationship between bullying and intention to leave , a cross-sectional study of 222 employees from various organizations in the UK found a weaker moderating effect of support from senior management . Additionally, even coworker support is not enough to reduce distress when individuals experienced high levels of workplace bullying because workplace bullying itself has a strong effect on mental health beyond worksite social support [13, 14]. It remains unclear whether specific forms of social support (e.g., supervisor or co-worker support) have a greater protective effect against workplace bullying. Also, there is no study that investigated these associations in a longitudinal design.
Social support from supervisors, co-workers, and family/friends moderates the relationship between employees’ exposure to workplace bullying and their subsequent psychological distress.
Although the definition of resilience varies in the literature, resilience, in general, refers to one’s ability to protect oneself from stressful life events, especially life-changing adverse events. For example, Connor and Davidson explained that “resilience embodies the personal qualities that enable one to thrive in the face of adversity” . On the other hand, Fletcher and Sarkar defined psychological resilience as “the role of mental processes and behavior in promoting personal assets and protecting an individual from the potential negative effect of stressors” . Resilient people tend to have high self-efficacy, past successes, a sense of control, a sense of humor, patience, optimism, supports from others, or personal goals in their lives . According to Wagnild ’s model, a person is resilient when he or she has a personal purpose in life, when he or she is determined to combat adversity to achieve his or her goal, when he or she keeps a balanced perspective on life, and when he or she uses humor to deal with life's stressors. Resilience enables one to thrive in the face of adversity such as combats or natural disasters and prevents one from developing mental illness such as psychological distress or post-traumatic stress disorder [17, 20]. Although resilience is often considered as personal characteristics or traits, it has been reported as one of the two mental capital which individuals can obtain in their life course . A systematic review of work-based interventions also indicates training such as Cognitive Behavior Therapy, self-regulation techniques, coaching sessions, etc. can improve personal resilience .
Experiencing workplace bullying is one of the adverse life events in working lives. Several studies have found a negative correlation between personal resilience and workplace bullying, as well as negative correlations between resilience and mental health outcomes . Recent cross-sectional studies have shown that resilience plays a mediating or moderating role in the relationship between workplace bullying and employees’ psychological health, emotional exhaustion, or physical strain [24,25,26]. These results showed that those employees who have higher levels of resilience have lower levels of emotional exhaustion, distress, or physical strain when they were exposed to workplace bullying. However, whether personal resilience prevents subsequent psychological distress among workers who experienced workplace bullying is unexplored in a longitudinal study.
Personal resilience moderates the relationship between employees’ exposure to workplace bullying and their subsequent psychological distress.
Stress coping styles
Coping skills are the other mental capital that moderate stress reactions and individuals can obtain in their life course, in addition to personal resilience . Original formulations of coping strategies consist of two dimensions: problem-focused coping (taking action and information seeking) and emotion-focused coping (change the way in which one thinks or feels a stressful situation, avoidance, and denial) . Seeking help and taking action are conceptualized as active strategies that may reduce stress reactions when individuals experienced stressful events, whereas avoidance and doing nothing are passive strategies that may increase stress reactions. In contrast to situation-specific coping strategies, coping styles refer to stable dispositional characteristics that reflect generalized tendencies to interpret and respond to stress . As reported that resilience may also be viewed as a measure of successful stress coping ability , individual differences in coping styles may act as moderators of the impact of stress on the results of stressful events.
Victims of workplace bullying are less likely to use problem-solving and more likely to use avoidance or resignation strategies than non-victims . The study in Iceland suggests that active coping styles are used at the beginning of bullying, but victims use more passive coping strategies as bullying becomes more serious . Previous research suggests different coping strategies have different effects on the association between workplace bullying and mental health. For instance, Bernstein and Trimm  reported that seeking help and assertiveness moderated the relationship between bullying and psychological well-being, while avoidance and doing nothing negatively impact its relationship. A systematic review  has reported that reappraisal coping, confrontive coping, practical coping, direct coping, active coping, social support, and self-care had a buffer-effect on the association between work stressors and bullying, while wishful thinking, emotional coping, avoidance, recreation, social support, and suppression had a boost effect on this association. However, a causal relationship remains unclear due to the cross-sectional design in the literature. Whether positive coping styles prevent employees from developing subsequent psychological distress after they experienced workplace bullying has not been investigated.
Positive coping styles moderates the relationship between employees’ exposure to workplace bullying and their subsequent psychological distress.