P1‐220: Creating a Driving Profile for Older Adults Using a Naturalistic Driving Methodology

Evaluation of older drivers has been largely dominated by controlled conditions such as on-the-road tests and driving simulators. Global positioning systems (GPS) and geographic information systems (GIS) provide a method for understanding driving behavior by analyzing continuous, objective data to determine driving patterns and the influence of personal, temporal, and environmental factors. The purpose of this investigation was to adapt existing, commercial, off-the-shelf, in-vehicle devices for research purposes to better understand driving behavior in older drivers over an extended period of time. We pilot tested a subset of twenty participants with normal cognition (Clinical Dementia Rating = 0, ≥ age 65) enrolled in a longitudinal study of preclinical Alzheimer disease and driving (R01 AG043434). The Azuga G2 Tracking DeviceTM was installed in each vehicle and collected data over a 5-month period (vehicle speed, latitude/longitude) every 30 seconds when the vehicle was driven. Aggressive driving (hard braking, speeding, sudden acceleration) was also recorded, and location data was collected every three hours when the ignition was off. Individual observations (“breadcrumbs”) and trip-level data were collected and analyzed in R and ArcGIS. Over 500,000 breadcrumbs representing almost 17,000 trips were collected. Spatial and statistical analyses determined each participant’s primary location(s), driving area, mean center of driving area, number and location of unique destinations, and number of trips. Primary locations (Fig. 1) were calculated in ArcGIS by aggregating breadcrumbs in areas where at least 10% of Ignition On/Off events occurred and were confirmed to be 100% accurate compared to known addresses. Driving Area encompassed all breadcrumbs for a given time period, while the Mean Center was the geographic center of observations in that period. Unique Destinations and Number of Trips were calculated for weekly and monthly intervals. Number of Trips was also calculated based on distance from primary location (e.g. 5 miles, 10 miles, Figure. 2), as well as on the number driven in daylight versus night (Figure. 3). Naturalistic Driving Profiles can be created for older adult drivers. Driving Profiles can be compared month-to-month or year-to-year, allowing researchers to identify changes in driving patterns that would not be available in controlled conditions. Primary Locations with only Ignition On/Off observations Trips within 5 and 10 miles from a primary location Trips by daylight status for five participants