Aggression Management in Mental Health Settings: The Impact of Dynamic Appraisal of Situational Aggression (DASA) and Aggression Prevention Protocol (APP) Interventions

Restraint and seclusion in psychiatric settings is associated with physical and psychological harm to patients and staff. Leveraging a dynamic aggression risk assessment instrument with targeted violence prevention can reduce aggression and restrictive practices in mental health. This study aimed to investigate the use of a predictive instrument with an aggression prevention protocol to reduce aggressive incidents. The Dynamic Appraisal of Situational Aggression (DASA) instrument assessed the risk of imminent aggression in psychiatric inpatients, and the Aggression Prevention Protocol (APP) provided staff with evidence-based interventions to reduce violence risk. DASA + APP were incorporated into standard practice within forensic and general adult inpatient units. The Modified Overt Aggression Scale (MOAS), restraint/seclusion events and pro re nata (PRN) medication were used to measure the impact of the intervention. Feedback was obtained from nursing staff to assess the feasibility and perceived utility of the intervention. There were significant reductions in average MOAS scores (pre=1.56, post=0.80, p = 0.007) and PRN medication administration (pre=4.14, post=3.63, p < 0.01). Restraint/seclusion events declined by 26% and seclusion hours by 51%. Staff perceived DASA as an objective, standardized communication tool; APP supported the least restrictive practices. This study supports the use of DASA + APP to identify the risk of aggression and guide proactive, individualized intervention. DASA + APP was effective in forensic and non-forensic units. Ongoing integration into clinical practice may enhance patient outcomes, staff satisfaction and treatment efficacy.

Plain Language Summary

Aggressive behaviour in psychiatric inpatient units can lead to harmful practices such as restraint, seclusion, and as-needed medication use. This study found that using a daily aggression risk assessment tool alongside a structured prevention protocol reduced aggression severity, restrictive interventions and medication use in both forensic and general psychiatric units.