Improving self-report measures of speeding

Improving self-report measures of speeding David Soole1, Ioni Lewis1, Judy Fleiter1, Sharon Newnam1, Angela Watson1 1Centre for Accident Research and Road Safety-Queensland There is continuing debate regarding the validity and reliability of self-report measures of behaviour, particularly in road safety research. Practical considerations often preclude the use of objective assessments, leading to reliance on self-report measures. This project sought not to argue whether self-report measures should continue to be used, but rather to investigate how current measures can be improved. This paper reports preliminary findings from exploratory qualitative research (focus groups and in-depth interviews) conducted with licensed drivers to explore the cognitive processes involved in responding to a range of self-report measures of speeding. Discussion themes included the perceived ease/difficulty of responding to, and the perceived accuracy of, the measures, as well as the influence of contextual and situational factors on behavioural reflections and subsequent responses (e.g., timeframe, type of roads, degree and frequency of speeding, and intentionality of the behaviour). Results indicated a preference for percentage-style response formats, as an alternative to Likert scales. In addition, heterogeneity in the timeframe of behavioural reflections suggested a need for specification in measures. Finally, discussions suggested liberal operationalisation of speeding amongst participants, irrespective of the degree over the speed limit, the inadvertent nature of the behaviour, or influence of other contextual factors (e.g., running late, driving with the traffic flow). This paper presents a discussion of these findings with a focus on identifying methods to improve self-report driving behavioural measures