The objectives of this study were to provide insights on how injury risk is
influenced by occupant demographics such as sex, age, and size; and to quantify
differences within the context of commonly-occurring real-world crashes. The
analyses were confined to either single-event collisions or collisions that were
judged to be well-defined based on the absence of any significant secondary
impacts. These analyses, including both logistic regression and descriptive
statistics, were conducted using the Crash Investigation Sampling System for
calendar years 2017 to 2021. In the case of occupant sex, the findings agree
with those of many recent investigations that have attempted to quantify the
circumstances in which females show elevated rates of injury relative to their
male counterparts given the same level bodily insult. This study, like others,
provides evidence of certain female-specific injuries. The most problematic of
these are AIS 2+ and AIS 3+ upper-extremity and lower-extremity injuries. These
are among the most frequently observed injuries for females, and their incidence
is consistently greater than for males. Overall, the odds of females sustaining
MAIS 3+ (or fatality) are 4.5% higher than the odds for males, while the odds of
females sustaining MAIS 2+ (or fatality) are 33.9% higher than those for males.
The analyses highlight the need to carefully control for both the vehicle
occupied, and the other involved vehicle, when calculating risk ratios by
occupant sex. Female driver preferences in terms of vehicle class/size differ
significantly from those of males, with females favoring smaller, lighter
vehicles.
