The University of Sheffield
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Intelligent Speed Assistance Study

posted on 2023-11-14, 13:31 authored by Marianne DayMarianne Day, Richard RoweRichard Rowe, Paul NormanPaul Norman, Damian Poulter, Ozgun Ozkan

Speeding is common on UK roads and increases the chance of crash. Intelligent Speed Assistance (ISA) is an in-car technology that helps drivers remain within the speed limit. Whenever the vehicle exceeds the speed limit, fuel transmission is reduced until the car returns to the limit. ISA technology is likely to become common in UK vehicles over the next 10 years and could reduce traffic injuries by up to 30%. The work proposed here involves exploring the perspectives of drivers on the introduction of ISA through qualitative interviews and a pre-interview questionnaire with (a) drivers who regularly drive a vehicle with an ISA system fitted and (b) drivers who do not currently have an ISA system in their car. The questionnaires will be analysed using content coding to identify beliefs around ISA use and adoption. The interviews will be analysed using qualitative thematic analysis to explore these perspectives in greater detail. These findings will be used to inform the development of a quantitative survey study of driver beliefs and intentions around the use of ISA and the construction of a Theory of Planned Behaviour-based intervention to encourage motorists to use ISA effectively.

Participant screening: Participants will be recruited through a brief screening questionnaire (attached document 3) presented online using the Prolific platform. This will identify samples of drivers who do and do not have ISA-type systems in their vehicles. Prolific allows the use of filters to ensure that the questionnaire will only be presented to certain groups. We will filter by country of residence (UK), car usage once a month, driving license, fluent in English and willing to take part in an online interview. The screening survey will ask participants which ISA systems are fitted in their car and whether they use them regularly. We will also ask for the make, model and year of manufacture for their vehicle (to check factory-fitted ISA systems) and their driving experience (how long they have had a driving license, miles driven a week) so we can match people in the ISA-user and non-ISA-user groups, when we invite them to the interviews. Prolific holds basic demographic data for the participants in their database. We will access age, gender and ethnic background. This information will also be used to match participants in the two groups. Participants will be asked to confirm that they would be willing to take part in an online interview. The screening questionnaire will take around 2 minutes to complete. This screening questionnaire will be presented on Prolific, in batches of 200, until we have a sample of 20-25 ISA-users who are willing to be interviewed. If we are not able to recruit 20 ISA users, we will invite drivers who have advisory systems in their car (e.g., warning alarms/lights when exceeding the speed limit). A sample of 20-25 non-ISA-users will be selected from the remaining respondents by matching as closely as possible for age, gender, ethnic background and driving experience, to the ISAusers. Main data collection: The samples of ISA-users and non-ISA-users will initially complete a pre-interview questionnaire (attached documents 4 and 5), delivered on Prolific. These questionnaires include open-ended text questions on using ISA, which are based on the Theory of Planned Behaviour (actual behaviour for those with ISA and imagined for those who do not). These questions seek to elicit behavioural beliefs (what is good or bad about using ISA), normative beliefs (who would approve or disapprove of using ISA) and control beliefs (what makes using ISA more and less likely). Once participants have completed the pre-interview questionnaire they will be contacted via Prolific's anonymous messaging service to arrange an interview. A one-to-one online interview will be conducted by a post-doctoral research assistant at a suitable time for the participant, guided by a semi-structured interview schedule (attached document 6). For ISA-users, questions will include: i. How their ISA system works. ii. How they use their ISA system (e.g., in terms of overriding it and turning it off). iii. How they would feel about amendments to the ISA that might make it harder to override/turn off. iv. How they felt about ISA before they drove a car with it fitted. v. How they think ISA should be introduced nationally. vi. What might facilitate or change their preferred approach to ISA introduction. For non-ISA-users, questions will include: i. What they know about ISA. ii. How they would feel about having a vehicle with ISA fitted. iii. How they think they would use the ISA system. iv. How would they feel about amendments to ISA that might make it harder to override/turn off. v. How they think ISA should be introduced nationally. vi. What might facilitate or change their preferred approach to ISA introduction. Interviews are expected to take 30-45 minutes and will be audio-recorded using Google Meet and transcribed using (automatic transcription). The transcripts will be checked and anonymised by the researcher and the audiorecordings wiped once the transcripts have been edited. Analysis: Data from the Theory of Planned Behaviour questionnaire will be content coded to identify, and measure the frequency, of beliefs about ISA-use in drivers who use, and do not use, the system. Interview data will be analysed using thematic analysis to transform the data into codes and themes. NVivo software will be used for coding and theme construction. A hybrid method will be used to include both deductive and inductive codes in describing and summarising the interview data. A coding frame will be agreed by the whole research team which will identify the range of beliefs identified in the transcripts and the frequency with which these beliefs are expressed by participants. The frame will be developed from a sample of early transcripts and applied and modified as it is applied to later transcripts. This iterative process will give a final coding frame which is applied to all the transcripts. Commonly identified beliefs about ISA-use will be taken forward into the next stage of the research programme, which will construct a quantitative questionnaire to measure beliefs about ISA usage in a large sample. This will be used to test which beliefs about ISA predict intentions to use it. We will seek ethical approval for the questionnaire study in a separate application.

The study received ethical approval from the University of Sheffield's Department of Psychology's ethics committee (ref: 044723).


The Road Safety Trust



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    Department of Psychology