Table 1.

Definitions of Conceptual Codes and Subcodes of Perceived Barriers of Modified Ride-on Car Usage.

Conceptual Codes	Definitions and Subcodes
Environmental	Any perceived barrier related to the environment. This may include the weather or the physical space.
Caregiver (includes families and clinicians)	Subcode: Physical Requirements. Any perceived barrier related to the physical effort or demand required to transition a child in/out of the ride-on car, provide arm’s length supervision, or assist with steering. Subcode: Motivation. Any perceived barrier related to the caregiver’s decreased motivation to provide their child with opportunities to use a modified ride-on car. Subcode: Time. Any perceived barrier related to the lack of time to provide their child with opportunities to use a modified ride-on car.
Child	Subcode: Health. Any perceived barrier related to a child’s health that prevents them having opportunities to use a modified ride-on car. Examples include sickness, general fatigue, or recovery from surgery. Subcode: Tolerance. Any perceived barrier related to a child’s tolerance to using a modified ride-on car. Examples include child’s willingness, lack of enjoyment, negative responses to movement or the sound/acceleration of the modified ride-on car. Subcode: Ability. Any perceived barrier related to a child’s physical or cognitive ability to using modified ride-on car. Examples include a lack of trunk control, inability to steer, low vision, lack of understanding cause and effect.
Device	Any perceived barrier related to the characteristics of the modified ride-on car. Examples include size of steering wheel, size of the ride-on car, loud sound, duration of battery, or quick acceleration.