A significant proportion of our sample reported experiences of workplace violence. We found that employees who experienced verbal violence in clinical settings had lower levels of perceived organizational justice and social support, higher levels of work-related stress and higher psychological problem scores than other HCWs. An important finding that emerged from this study is that isolated workers (with low social support) are exposed to violence, and that employees who experience violence are psychologically distressed. They manifest high levels of job strain and perceive their health care facility to be unfair. We also observed an interesting association between lifetime exposure to internal non-physical violence and low job control. Perceived control is a measure of power in the organization and it is significant that verbal violence, which is an abuse of power, is exerted by colleagues on workers with less authority. The cross-sectional nature of our study prevents us from indicating a definite cause for the association between violence and psychosocial variables. However, the association of workplace violence with high demand and psychological disorders, and the protective role of job control, social support and organizational justice suggest that preventive programs should target these variables.
The repercussions resulting from violence in the workplace are important as they can lead to a deterioration in staff health. A systematic review of studies on aggression showed that despite differences in countries, cultures, research designs and settings, the responses of health care workers to patient aggression are similar and include immediate responses such as frustration, fear, anger or anxiety [9, 43]. These responses may also extend to become addiction , burnout , post-traumatic stress disorder, guilt, self-blame, and shame , an intention to quit nursing and an intention to change institution . These psychological effects can persist for months or years after the original event occurred . Our study confirms that non-physical violence is associated with high work-related stress, high psychological distress and the perception of unfairness on the part of the health care facility/organization. The most likely interpretation of this result is that violence causes stress and a perception of injustice, but the cross-sectional nature of the study does not exclude the theory (suggested by some authors [14, 22]) that stressed workers are more likely to be victims of violence.
As expected, nurses were the category most exposed to physical violence. Nurses are more likely to encounter aggressive behavior because of the amount of time they spend providing direct patient care. Studies show that the chances of suffering physical violence are 7.2 and 9.0 times greater for healthcare workers with moderate and high patient contact, respectively, than for those with little or no contact . In our sample, the percentage of nurses reporting one episode of physical aggression over the previous year (11.5 %) roughly corresponds to the average one-year aggression rate found by Hodgson et al. in 142 American hospitals , and by Gerberich et al.  in the Minnesota Nurses’ study on 6,300 randomly selected nurses. Our study shows that physicians are also at a significant risk of aggression. Contrary to what is normally seen, in some cases the rate of aggression was higher for doctors than for nurses. This may be due either to the role and decision-making power of doctors, especially in some high-risk medical services, or to the fact that nurses tend to report incidents less frequently than doctors.
Respondents from the psychiatric department experienced the highest overall level of patient-initiated aggression. One out of three workers reported being assaulted in the previous year, and almost three quarters of these workers had experienced physical violence during their working life. The A&E (accident and emergency) department also seemed to be a particular target for physical and verbal aggression. More than half of all the reported cases of physical and verbal violence had occurred in these high-risk departments. A high prevalence of violence in psychiatric settings has been observed in earlier studies  and confirmed in subsequent ones [12, 13, 27, 49, 50]. Both patient complaints originating from environmental conditions and poor communication  and staff-related factors, such as low work experience [12, 48], low general health , anxiety  and low job satisfaction [47, 48], are associated with aggression. The incidence of workplace violence in the emergency department has been well documented in numerous published studies [49–55]. Besides nurses and physicians, other professionals working in psychiatric [27, 56] and emergency departments  are also at risk.
Our study has several limitations. Firstly, since our investigation was limited to a single health care district, we cannot extend our findings to all Italian health care services. However, our results are in agreement with the literature, and we have no evidence to suggest that the situation is different in other health care facilities.
Secondly, the survey was a retrospective one, with the usual limitations of inaccurate recall of past events and of possible contamination by current events. However, the repeated measurement of aggression rates over time and their relative stability indicate that the phenomenon exists. The present study had a high participation rate compared to other similar studies on this topic, thereby increasing our confidence in the results.
Thirdly, this study was limited to an exploration of abuse from a worker perspective; no attempt was made to validate the episodes reported. In fact, no objective criteria for misconduct were specified, and the findings presented here should be considered hypothetical. What workers perceived as misconduct may not constitute misconduct in an objectively ethical or legal sense. However, it is the perception of the event and not the event itself that may have the greatest impact on the individual . It has also been suggested that it may be in the interest of some professionals and labor unions to highlight rates of violence in the workplace as a way of enhancing their role in protecting workers . By informing workers of the opportunity to fill in a VIF during their periodical medical examination, we chose a method that was unlikely to be influenced by the interests of consultants or unions.
Fourthly, the present study relied on self-reported measurements, which could lead to problems associated with an inflation of the strength of relationships and with the common method variance. However, to minimize problems with self-reports we used well-known validated questionnaires that have shown good reliability. Moreover, although we attempted to exclude all possible confounders, we cannot rule out the existence of residual confounding.
Our study has some strong points. The collection of data on the part of a physician who was not a direct employee of the health care facility, but who had a direct knowledge of workplaces and had had a long-lasting relationship with workers, increased the response rate and reduced the likelihood of inappropriate responses. Furthermore, this method could encourage workers to take part in prevention by suggesting possible remedies for workplace violence.
We fully agree with the suggestion of the Italian Ministry of Health that an assessment of violence is necessary in all health care organizations. No paramount episode of violence had been reported to the occupational physician before workers began completing the questionnaires.