Doctors and Nurses: A Systematic Review of the Risk and Protective Factors in Workplace Violence and Burnout

The present study aims analyze the risk factors that lead to high levels of burnout among nurses and physicians and the protective factors that prevent them. Thus, it is also intended to explore the possible correlation between physical and verbal violence produced at work and the symptoms derived from burnout. Methods: The search was carried out on the Scopus, PubMed and Web of Science databases between 2000 and 2019 (on which date the bibliographic search ends). Descriptive studies estimating the prevalence of workplace violence and risk and protective factors and burnout were included. An adapted version of the Downs and Black quality checklist was used for article selection. 89.6 percent of the studies analysed were in the health sector. There is a significant correlation between burnout symptoms and physical violence at work. On the one hand, the risk factors that moderate this correlation were of structural/organisational type (social support, quality of the working environment, authoritarian leadership, little autonomy or long working days, etc.) and personal type (age, gender, nationality or academic degree, etc.). On the other hand, protective factors were the quality of the working environment, mutual support networks or coping strategies. The results were analysed in-depth and intervention strategies were proposed.


Introduction
Workplace violence (WV) is understood as any type of act, incident, or behavior in which a person is abused, threatened, humiliated, or assaulted in the workplace, including verbal and physical assaults [1]. The National Institute of Safety and Hygiene in the Workplace (Spanish acronym: INSHT) affirms that WV is one of the main health risk factors for those who are active in the workplace, since such actions result in a multitude of psychological and emotional conditions that prevent the development of a 'working life or aggravate the problems that occur regardless of work. The many studies related to WV have observed that the risks of exposure to this type of situation are very high in those jobs that imply providing a service to people, so the nursing and medical profession would stand out for the nature of one's own work as a facilitator for the creation of WV situations [2]. The WV is characterized by being diverse in its ways of expressing itself, physically (hitting, pushing, kicking . . . ) verbally (yelling, insults, offensive comments in general . . . ) or sexually [3].
Previous models related to working conditions and the work environment assumed that workplace violence was based exclusively on situations involving physical violence, leaving aside stress, overwork, or the psychological demands of the task itself [4]. Since then, many authors have focused their work on discovering the causes and consequences that it occurs 'daily'. For example, Mucci [5] observed that working conditions such as high work demands, job control, type of leadership, peer support, company organization, and even gender (higher among women than among men) correlated with WV. Following at work to identify those studies that were not published in the databases (13.2%

Data Extraction
Data extraction was performed using a standard data extraction form developed by the Joanna Briggs Institute Reviewers' Manual for The Systematic Review of Prevalence and Incidence Data [21]. We used a specific coding manual to extract information from the primary studies. To ensure rigor in the final selection of studies, the three reviewers ran the form through all of the articles to check their suitability, relevance and precision.

Inclusion Criteria
Studies were included according to the following criteria: (a) empirical; (b) published between 2000 and 2019 (on which date the bibliographic search ends); (c) empirical studies; (d) published in Spanish, Catalan or English; (e) the articles must evaluate t burnout syndrome with the standardized Maslach Burnout Inventory questionnaire [22]; (f) compare burnout levels in medical and nursing professionals; (g) evaluating at least one type of WV (physical, verbal or sexual); (h) aiming to observe the protective and risk factors related to WV. Articles of an informative nature, experts' opinions published in editorials and letters to the editor were excluded ( Figure 1). The diagram was made following the PRISMA declaration [23].

Selection of the Studies
The main search yielded a result of 949 posts. The first selection phase was carried out based on reading the titles and abstracts of the publications; 253 articles were selected for further study. The exclusion criteria in this first phase were: non-empirical studies, not published before the year 2000, not written in Spanish, Catalan or English, not being directly related to workplace violence towards health professionals and not evaluating burnout with the MBI. The selection was then examined by means of a complete reading of the articles taking into account the inclusion criteria. Finally, 59 documents were selected for their final review. 13.2% of the final selection came from Google Scholar and institutional portals.

Data Analysis Section
Variables and information extracted from the studies. Literature search results and data extraction results were summarized descriptively. To exclude duplicate articles, we used the program Endnote for manual selection. A summary of efficacy outcomes was presented based on the different outcome measures, controls and interventions. A narrative synthesis was therefore generated, considering the total number of studies that reported results, the methodological quality, and the quality of evidence for the outcomes to yield final conclusions. The general characteristics of systematic reviews extracted were used as exploratory variable PRISMA scores. We included: number of authors, nurses versus physicians, percentage of women versus men, transversal studies versus other methodological interventions, type of burnout and WV instrumentals used in the study, presence of risk and protectives factors versus absence. If the value of these factors was p-value < 0.05, it was considered statistically significant for the systematic review.

Results
The results of the final selection of the studies are show on Table 1 (See Table 1). The information in Table 1 allowed us to calculate the statistics. The descriptive results are shown on Table 2 (See Table 2). The total population analysed was 22,993 (N = 22,993), with a mean age of 34.18 (Mean= 34.18; SD = 6.14). A higher women's employment rate can be observed in the world health sector, representing 61.43% (N = 14,126) of all studies, men being at 38.56% (N = 8867). Most of the research related to burnout and WV is focused on the nursing profession, with 71.64% (N = 16,473) representing the nurses who have been evaluated. Doctors appear to take up 28.49% (N = 6551) of the research, and a lower percentage is taken up by nursing assistants, orderlies and/or technicians, 1.16% (N = 269). The most evaluated specialties are the ICU or Intensive Care Unit (Critical Care) (N = 9344; % = 40.63%), Emergencies (N = 6719; % = 29.22%), the Mental Health specialty (N = 4236; % = 18.54%) and Surgery (N = 4187; % = 18.45%). In terms of work contracts, those of a fixed or full-time nature are the most frequent, 57.66% (N = 13,258), as are, to a lesser extent, part-time-28.07% (N = 6456)-and temporary contracts-14.02 (N = 3279). The university academic level is most common among the population examined, 38.02% (N = 8793), as is experience of between 5 and 15 years, 42.11% (N = 9683).       Table 3 (See Table 3) shows the results of the mean of the different levels that make up burnout. Regarding gender, we can observe that women in the health sector appear to suffer from higher burnout levels than men. For example, women (x = 28.2; SD = 6.0) seem to have higher levels of EE compared to men (x = 24.3; SD = 6.5) and the same hold with DP, in which women get a score of (x = 12.2; SD = 4.2), while that for men is (x = 11.7; SD = 4.2). The PA subcategory is the only variable in which men (x = 24.3; SD = 7.2) obtain a higher score than women (x = 25.4; SD = 7.2). Regarding the professional category, it is nurses who obtain the worst results in terms of EE (x = 28.1; SD = 6.1) to DP (x = 11.9; SD = 4.0) and PA (x = 25.1; SD = 6.7). In the specialty area, there are three categories with very similar values, including the Intensive Care Unit (ICU) with an EE of (x = 29.1; SD = 6.4), a DP of (x = 12.8; SD = 3.9) and a PA of (x = 27.7; SD = 6.3). The Emergency specialty has an EE of (x = 29.6; SD = 6.1), a DP of (x = 10.8; SD = 4.1) and a PA of (x = 25.4; SD = 7.3). Similar values were found in the Mental Health specialty, with an EE of (x = 28.0; SD = 6.5), a DP of (x = 12.1; SD = 3.9) and a PA of (x = 28.6; SD = 5.9). Table 4 (See Table 4) shows the main characteristics of violence and the protective and risk factors that promote it. The vast majority of the studies analysed (N = 65; % = 90.2%) show that the most frequent causal agent endured by healthcare professionals is the patient; to a lesser extent, family members or partners (N = 26; % = 36.1%); and finally, coworkers (N = 11; % = 15.2%). The most common type of violence, as collected by all the investigations, are verbal (N = 72; % = 100%), including shouting, insults or threats. Workers claim that at some time in their working life they have suffered some type of physical violence (N = 57; % = 79.1%) and, to a lesser extent, a sexual assault (N = 23; % = 31.9%). Regarding risk and protective factors, it should be clarified that any action contrary to a risk factor, or that goes in the opposite direction, is understood as a protective factor. Thus, the factors were classified into two series of categories, the structural/organizational type, and the personal type. For example, within the former group, 97% (N = 70) of the studies analysed found that social support from coworkers is one of the risk and protective factors that most affect workplace violence in the healthcare sector; this would also be highly influenced by family support (N = 35; % = 48.6%). A determining factor seems to be the professionals' type of contract, full-time (N = 48; % = 66.6%) or part-time (N = 36; % = 52%). The quality of the work environment (N = 17; % = 23.6%), the type of leadership of the plant manager (N = 22; % = 30.5%) and the level of autonomy (N = 9; % = 12.5) are among the other risk and protective factors found. On the other hand, personal factors are those related, for example, to workers' job satisfaction (N = 70; % = 97.2%), coping strategies (N = 28; % = 38.8%), self-efficacy (N = 12; % = 16.6%) or empathy (N = 11; % = 15.2%).

Discussion
The objective of this systematic review is to observe the levels of WV and burnout in the healthcare sector and to verify the most influential risk and protective factors.
The analysis of the results of the different studies finally selected shows that there is a high percentage of professionals who at some time in their working lives have been exposed to some type of WV, whether verbal, physical, or sexual. This, in turn, appears to affect the high levels of observed burnout, which are higher among women than among men, although this may also be due to the large female representation in the total sample. Following in this same line, according to the Labour Force Survey (LFS) developed by the National Institute of Statistics (INE, from its Spanish initials) in Spain, with data from the last quarter of 2018, women appear to hold 71.7% of jobs in the healthcare sector [82]. Among many other variables, the burnout of professionals is mainly influenced by their specialization, type of work employment and their experience within the field. When it comes to the type of contract, full-time employment involves more effort on the part of the worker and requires greater attitudinal resources to carry out the work required, these cause greater emotional exhaustion (EE), lower feelings of personal accomplishment (PA) and therefore more negative thoughts about their competency (DP) [28].
In relation to the profession among nurses and doctors that suffers the greatest WV, the nursing profession faces the most exposure. This is due, in large part, to the fact that they are directly in contact with patients. They are, therefore, the first exposed to complicated situations that require a lot of control and that generate great emotional wear. Various studies have shown that it would be the nurses who, due to the situations of experienced violence, would obtain the worst levels of burnout and emotional intelligence. This would translate into high levels of anxiety, lack of self-esteem, insomnia problems, depression or even physical effects such as a higher percentage of those suffering from cancer. [83] The specialties in which higher levels of burnout are contemplated are actually those in which patients are in the most serious conditions and which require more need to manage unpredictability in the workplace, as can happen in the Intensive Care Unit (ICU), in the emergency room, or in the mental health area, which involves unpredictable patients with low levels of self-control [84]. These studies corroborate that high levels of burnout in specializations where the patient's life may be in danger correlate with a high percentage of WV [85], mainly from the patients, family members or partners. It can be seen that despite the pressure affecting nurses, doctors and nursing assistants, among others, there is not a high percentage of attacks on the part of coworkers.
There are many risk factors that make WV more likely. If one examines them indepth, what is striking is that those with the most impact are related to high levels of effort (structural and/or organizational factors) and workers' lack of self-control and selfregulation skills (personal factors). Two types of factors were categorized for a better understanding, but neither should be understood separately, but rather as a set that affects and influences everyone equally. For example, a healthcare professional who has a fulltime work contract is more likely to be exposed to WV, since this entails greater emotional exhaustion, and more exposure to extreme situations and to all types of people with multiple reactions. We understand, in accordance with the results, that this probability of experiencing WV will increase if he or she works within a specialty in which moments of great tension and stress are experienced. However, in relation to this equation, various types of factors, both organizational and personal, can considerably reduce the WV suffered, such as a healthy work environment, high levels of social support from colleagues, or even possessing intrinsic coping strategy, self-efficacy and adaptation resources. These, in turn, would increase job satisfaction and therefore reduce the frequency of WV [86], causing burnout levels to decrease drastically, with the health benefits this environment entails [87].
It is here, therefore, that the role of institutions becomes important. Creating intervention programmes that aim to alleviate levels of WV should be a priority. For example, the Zero Tolerance Policy is a political campaign, spread all over the world, a benchmark in the United Kingdom that includes several organizations such as the British Columbia Occupational Health and the Safety Agency for Healthcare and the National Health Service (NHS) [30], and addresses the issue of violence against healthcare workers on the part of co-workers and beneficiaries. This campaign provides healthcare personnel with the necessary resources, such as courses or workshops and the creation of support networks within the community, and promotes awareness in relation to patients to show the reality of this matter. For this, a positive work culture must be created where all those involved (workers and patients) treat each other with respect, with a focus on positive work recognition and conflict resolution [88]. The application of these types of policies can have a great benefit for workers, such as a more positive responses to stressful situations [61].
Another very similar program was the Assaulted Staff Action Program (ASAP), which aimed to identify "high-risk" patients (with a criminal record or previous reports of high levels of aggression) and to give workers suitable warning prior to the visit. According to some studies, it was shown that WV decreased significantly when using this method [88]. In that sense, it is important to note that workplace violence is one of the possible causes of burnout in the health sector [81].
Therefore, this is not merely an internal struggle on the part of workers when facing patients. Government agencies should also be the main stakeholders and work alongside other parties to reduce such incidents, as the quality of the healthcare sector depends on the satisfaction of nurses, doctors and other specialized employees.

Limitations and Future Research
The present systematic review has some limitations. The inclusion and exclusion criteria were clearly defined, but more research into a more specific database such as CINAHL (Cumulative Index to Nursing & Allied Health Literature) would be advised in the case whereby an article only appears in it and not in WOS. There is also the risk of an article included in the so-called gray literature (doctoral theses, etc.) that was not located.
It would be interesting in future studies to focus on examining other variables considered relevant in the selected studies on psychoeducational intervention programs in which this instrument is applied. In this sense, this study can provide useful information to researchers and professionals for decision-making in this thematic line. More longitudinal research is required focused on evaluating the effectiveness of programs for the prevention of burnout and that not only focus on studying the effects of burnout on healthcare workers but also, for example, in the university environment. In addition, despite the importance of improving well-being and quality of life, there are several policies that could be sought to reduce the WV they experience throughout their professional lives.

Conclusions
It can be concluded that workplace violence is one of the possible causes of burnout in the health sector.
The risk and protective factors were classified into two series of categories, the structural/organizational type (for example, social support from coworkers, family support, professionals' type of contract, the quality of the work environment) and the personal type (for example, workers' job satisfaction, coping strategies, self-efficacy, empathy, etc.). Regarding risk and protective factors, it should be clarified that any action contrary to a risk factor, or that goes in the opposite direction, is understood as a protective factor.
As we can see, there are many studies that have studied the effects of burnout on workers in the health sector, but there are few action policies that aim to reduce the WV they experience throughout their professional lives. We must emphasize that this would imply not only action from within the healthcare sector but more re-training and building awareness in society about the importance of such work, and to provide enough information to control all kinds of uncontrolled impulse in emergency situations.
We can point out the importance of institutions promoting recommendations and policies that can develop empathy and a positive work culture where those involved treat each other with respect, recognition, and work to prevent workplace violence, work stress and improve the quality of life and well-being of its members.

Data Availability Statement:
The data could be requested by the scientific community in the ethical terms to be determined.

Conflicts of Interest:
The authors declare no conflict of interest.