What aspect does the SFST largely focus on when assessing a driver?

The SFST focuses primarily on assessing a driver's cognitive and physical abilities because these factors are critical in determining their ability to operate a vehicle safely. The test examines how well individuals can perform a series of tasks that require coordination, balance, attention, and mental processing, which are all indicative of their level of impairment, particularly in relation to alcohol or drug influence.

Cognitive abilities are evaluated through tasks that require understanding and executing instructions, demonstrating the driver's capacity to process information and make sound decisions while driving. Physical abilities are assessed through tasks that measure balance, coordination, and motor skills, which are crucial for maintaining control of the vehicle. By examining both cognitive and physical functions, the SFST provides a comprehensive assessment of a driver's overall impairment, which is essential for making informed decisions regarding sobriety and road safety.