Effect of police mobile computer terminal interface design on officer driving distraction Maryam Zahabi, David Kaber * Edward P. Fitts Department of Industrial & Systems Engineering, North Carolina State University, United States article info Article history: Received 26 February 2017 Received in revised form 14 August 2017 Accepted 12 September 2017 Keywords: Mobile computer terminal Driver performance Attention allocation Workload Situation awareness abstract Several crash reports have identified in-vehicle distraction to be a primary cause of emergency vehicle crashes especially in law enforcement. Furthermore, studies have found that mobile computer terminals (MCTs) are the most frequently used in-vehicle technology for police officers. Twenty police officers participated in a driving simulator-based assessment of visual behavior, performance, workload and situation awareness with current and enhanced MCT interface designs. In general, results revealed MCT use while driving to decrease officer visual attention to the roadway, but usability improvements can reduce the level of visual distraction and secondary-task completion time. Results also suggest that use of MCTs while driving significantly reduces perceived level of driving environment awareness for police officers and increases cognitive workload. These findings may be useful for MCT manufacturers in improving interface designs to increase police officer and civilian safety. © 2017 Elsevier Ltd. All rights reserved. 1. Introduction In the U.S., there are three main categories of emergency ser- vices including: firefighting, emergency medical services (EMS), and law enforcement. According to Karter and Stein (2012) and Reaves (2011), there are 30,100 fire departments and 17,985 state and local law enforcement agencies throughout the Country that provide emergency services. A large number of firefighters, para- medics, and police officers at these agencies spend most of their work shift in emergency vehicles. The National Highway Traffic Safety Administration (NHTSA) Fatality Analysis Reporting System (FARS) and General Estimate System (GES) reports from 2002 to 2012 indicated that police vehicles are involved in significantly more fatalities in comparison to fire or emergency medical vehicles. One possible explanation for the greater numbers of crashes and fatalities for police might be the larger number of police cruisers in comparison to other emergency vehicles and the fact that police vehicles are more likely to be single-crewed (Yager et al., 2015). It is important to note that the number of reported crashes are in ab- solute terms and does not consider miles driven. Several studies identified in-vehicle distractions to be a primary cause of emergency vehicle crashes (e.g. Yager et al., 2015; Abdelwanis, 2013). 1.1. Effect of in-vehicle technology use for normal drivers Driver distraction has been defined as “diversion of attention from activities critical to safe driving for performance of a sec- ondary competing activity” (Lee et al., 2009). The effect of visual and cognitive distraction caused by in-vehicle technologies on civilian driver performance, and attention allocation has been examined through many studies documented in the literature. For example, Liang and Lee (2010) conducted an empirical study to investigate the combined effect of visual and cognitive distraction on driver performance caused by a secondary navigation task and made comparison with only visual or cognitive distraction effects. Results showed that visual distraction interferes with driving per- formance more than cognitive distraction, and visual distraction dominates performance decrements during combined distraction. In a more recent study, Kaber et al. (2012) also assessed the effect of visual, cognitive, and simultaneous distraction of an in-vehicle navigation aid on operational and tactical driver behavior. Their results showed that tactical behavior is more demanding in terms of cognitive distraction than operational behavior. In addition, they found that visual and cognitive distraction both increase driver workload but in different ways in terms of vehicle control and gaze behavior. Related to this, several studies have found the use of in- * Corresponding author. Dept. ISE, North Carolina State University, 400 Daniels Hall, Raleigh, NC 27695-7906, United States. E-mail address: dbkaber@nscu.edu (D. Kaber). Contents lists available at ScienceDirect Applied Ergonomics journal homepage: www.elsevier.com/locate/apergo https://doi.org/10.1016/j.apergo.2017.09.006 0003-6870/© 2017 Elsevier Ltd. All rights reserved. Applied Ergonomics 67 (2018) 26e38