Question Justification

Justification for Qualification Survey

Item number 1 (Date of Birth)

This item asks the respondent his/her date of birth. If the individual is less than 60 or over 79 years of age, they are not eligible for the study. Date of birth is being asked because the individual may have a birthday between the time of the survey and actual participation in the study sessions which may qualify/disqualify them from participating.

Item number 2 (Sex)

The study will attempt to qualify approximately equal numbers of males and females at each of the desired electronic navigation system (ENS) experience levels.

Item numbers 3-4 (Race and Hispanic Origin)

These are standard demographic items being collected for classification purposes.

Item number 5 (License status)

To ensure participants were all licensed under a similar licensing system, only drivers with a valid North Carolina driver’s license will be accepted into the study. Participants who have unusual vision (e.g., a bioptic telescopic lens) or hearing aid requirements, or have driving distance, road type, or interlock restrictions will not be selected to participate in an attempt to make each ENS experience level group as homogeneous as possible.

Item numbers 6-6c (Vehicle regularly drive; vehicle type, availability, ownership, insured)

This series of questions assesses whether the respondent has a vehicle he/she regularly drives, whether the vehicle type is suitable for the study, whether it is available for the study, who owns the vehicle, and whether the vehicle is insured. A volunteer will be excluded if the vehicle driven most regularly is more than 12 years old or is exotic in some way (e.g., low profile sports car with limited visibility) that could affect study outcomes. While the individual does not have to own the vehicle to be driven, it must be available to the volunteer for use in the study, and the person must have proper insurance for the vehicle.

Item number 7 (Driving frequency)

This question asks how many days a week the respondent drives. Participants must drive at least three times a week to be considered sufficiently active drivers for inclusion in the study.

Item numbers 8-10 (ENS use, ENS programming, preferred navigation method, ENS skill)

This series of items is used to determine how often potential participants use an ENS for guidance, what type they use most often, and their preferred navigation method. These items are critical for classifying participants as familiar or unfamiliar with ENSs, are specific to the purposes of this study, and are the foundation for group assignment for the data collection efforts.

Item number 11 (Interest in participation)

This item describes study requirements and incentives, and asks whether the person is interested in participating.