Using Space Syntax Analysis to Measure Patient Aggression Risk

Objectives: The present study investigates whether space syntax offers appropriate tools for identifying risks of aggression, interventional opportunities, and environmental design strategies to reduce the risk of Type II violence in emergency departments. Background: Although healthcare workers are a relatively small percentage of the U.S. workforce, they sustain almost 75% of workplace assaults. Poor environmental design has been identified as an antecedent to aggression by patients and/or their companions. Method: Guided by Rational Choice Theory, Lifestyle Exposure Theory, Routine Activity Theory, and Crime Prevention through Environmental Design (CPTED), the study uses five visibility graph analysis (VGA) measures: visibility, control, controllability, mean visual depth, and occlusivity. Three U.S. hospital-based emergency departments were selected. First, a VGA was performed on all three layouts. A second VGA was performed after excluding unconnected spaces, and a third was performed on key patient and staff areas. Last, a fourth VGA was conducted after performing physical modifications to the three departments. Results: Statistical analysis revealed significant differences in VGA measures not only between different layouts but also between the original and modified layouts. Specifically, small changes created by architectural features can affect visual access and exposure as measured by space syntax. Alcove-style spaces in key staff areas are also associated with limited visual control of the local environment. Typically, in smaller zones, central staff workstations afford better control of patient spaces. Conclusion: This study shows that space syntax analysis is a useful tool for identifying risks of aggression in hospital spaces and for identifying interventional opportunities.