Incidence and risk factors of workplace violence on psychiatric staff

BACKGROUND: A study by Hesketh et al. found that 20% of psychiatric nurses were physically assaulted, 43% were threatened with physical assault, and 55% were verbally assaulted at least once during the equivalent of a single work week. From 2005 through 2009, the U.S. Department of Justice reported that mental health occupations had the second highest average annual rate of workplace violence, 21 violent crimes per 1,000 employed persons aged 16 or older. OBJECTIVE: An evaluation of risk factors associated with patient aggression towards nursing staff at eight locked psychiatric units. PARTICIPANTS: Two-hundred eighty-four nurses in eight acute locked psychiatric units of the Veterans Health Administration throughout the United States between September 2007 and September 2010. METHODS: Rates were calculated by dividing the number of incidents by the total number of hours worked by all nurses, then multiplying by 40 (units of incidents per nurse per 40-hour work week). Risk factors associated with these rates were analyzed using generalized estimating equations with a Poisson model. RESULTS: Combining the data across all hospitals and weeks, the overall rate was 0.60 for verbal aggression incidents and 0.19 for physical aggression, per nurse per week. For physical incidents, the evening shift (3 pm 11 pm) demonstrated a significantly higher rate of aggression than the day shift (7 am 3 pm). Weeks that had a case-mix with a higher percentage of patients with personality disorders were significantly associated with a higher risk of verbal and physical aggression. CONCLUSION: Healthcare workers in psychiatric settings are at high risk for aggression from patients.