The four road safety messages (i.e., physical gain-framed, physical loss-framed, social gain-framed and social loss-framed) were taken from Kaye et al. (2013). To ensure that the messages were age-appropriate (i.e., suitable for drivers from the 17 to 25 year old
population), they were piloted on a younger sample of participants in Studies 1a-c than in Kaye et al. (2013). Further, while the messages functioned as intended in Kaye et al. (2013), the social messages were longer than the physical messages and may have potentially lead to memory load and/ or word confounds. Accordingly, an additional sentence was added to the physical messages (i.e., “Driving under/ over the posted speed limit decreases/ increases the severity of physical injuries you and your passengers may sustain in the event of a crash”) to control for length between the two message types. The gain-framed messages were designed to activate the BAS, while the loss-framed messages were designed to activate the FFFS, which prior research supported (Kaye et al., 2013; see Table 6.1 for the message stimuli used in this program of research).
80 Table 6.1
Initial Version of the Road Safety and Motor Vehicle Messages as Presented to Participants in Studies 1a, 1b, and 1c
Physical loss-framed message
Each year in Australia, approximately 400 people will die if drivers do not obey the speed limits
By not obeying the speed limits, you are increasing your risk of crashing and not protecting yourself and your loved ones
Driving over the posted speed limit increases the severity of physical injuries you and your passengers may sustain in the event of a crash
Slow down, monitor your speed
Physical gain-framed message
Each year in Australia, approximately 400 people will be saved if drivers were to obey the speed limits
By obeying the speed limits, you are decreasing your risk of crashing and protecting yourself and your loved ones
Driving under the posted speed limit decreases the severity of physical injuries you and your passengers may sustain in the event of a crash
Slow down, monitor your speed
Social loss-framed message
When you choose to speed with your friends in the car, you’re showing them that you really don’t care about their safety
Although they probably won’t say it, your friends will feel less comfortable and less confident with you as a driver when you do speed
By speeding, you’re not putting your friends’ safety first and not being the best friend you can be
Slow down, monitor your speed
___________________________________________________________________________
81 ___________________________________________________________________________
Social gain-framed message
When you choose not to speed with your friends in the car, you’re showing them that you really do care about their safety
Although they probably won’t say it, your friends will feel more comfortable and more confident with you as a driver when you don’t speed
By not speeding, you’re putting your friends’ safety first and being the best friend you can be Slow down, monitor your speed
Motor vehicle message
This high performance sports model can achieve 0 to 100 km/h in 6 seconds and exceeds 200 km/h in 11.8 seconds
This vehicle is powered by a turbo V8 engine and reaches a top speed of 290kms/per hour The Extreme Xx sports model is one of the fastest street legal vehicles permitted on Australian roads
You will be the envy of all your mates if you test drive one today
___________________________________________________________________________
Note. Differences between the gain-framed and loss-framed messages are highlighted in bold.
6.4.2 Development of the motor vehicle message
The motor vehicle message was developed in the current research with the intent to activate the BIS (when paired with the conflicting goals of the social loss-framed message) in Study 2 and, as such, was devised specifically to highlight the high speed capabilities of a high performance vehicle (see Table 6.1). As discussed in chapter 2, activation of the BIS is theorised to occur when individuals are exposed to conflicting cues, such as both FFFS/
punishment cues (e.g., social loss-framed message that emphasises the negative consequences of speeding behaviour) and BAS/ reward cues (e.g., a motor vehicle message that promotes a vehicle designed to reach high speeds). The motor vehicle message was piloted for its
82 suitability in Study 1b to test and control for potential word confounds (e.g., valence and
arousal differences) between the word stimuli used in the motor vehicle message and the word stimuli used in the social loss-framed message that could influence individuals’
reactions towards these messages. Further, in Studies 1b and 1c, the motor vehicle message was examined in its entirety to assess the relevance and believability of this message.
6.4.3 Word stimuli selection
In Study 2, a word/ non-word lexical decision task (LDT)17 was used to assess message processing. While a large number of studies have used the LDT to assess RT to word stimuli (e.g., Borkenau, Paelecke, & Yu, 2010; Christopherson & Ferraro, 2009;
Noguera, Ortells, Abad, Carmona, & Daza, 2007), past research has shown that RTs to words can be influenced by a number of factors. These factors include, for example, word frequency (i.e., faster RTs occur for more frequent than less frequent words; Scarborough et al., 1977), word length (i.e., shorter words result in faster RTs than longer words; New, Ferrand, Pallier,
& Brysbaert, 2006), concreteness or abstractness of the words (i.e., concrete words are identified faster than abstract words; Kroll & Merves, 1986), and word type (i.e., faster RTs occur for nouns than verbs; Gomes, Ritter, Tartter, Vaughan Jr., & Rosen, 1997). These factors represent potential confounds of studies of word and/ or sentence processing, and were therefore assessed in Studies 1a and 1b.
The SUBTLEXUS lexical corpus was used to control for word frequencies in the initial selection of the words used in the physical messages, social messages, and motor vehicle message (Brysbaert & New, 2009). An independent groups t-test revealed that there were no significant differences between the physical and social word frequencies, t(24) = 0.14, p = .891, 95% CI [-513.05, 587.22], nor between the social and motor vehicle message word
17 Chapter 7, section 7.2.2, provides further information on the LDT used in Study 2.
83 frequencies, t(24) = -0.16, p = .878, 95% CI [-907.31, 780.11].18 As required, similar word
frequencies were obtained for the message words lists. To control for word type, each word list consisted of 13 words and included an equal number of nouns, adjectives, and verbs.
Further, each word list contained a similar number of concrete and abstract words and ranged from three to 11 letters.19
For the purpose of Studies 1a and 1b, two to three filler words were selected for each message word. Filler words were matched to the message words on word frequencies, word length, number of syllables, and word type. Further, to prevent the filler words from
confounding the study’s results, the filler words were different to those words which were presented within the message stimuli. In Studies 1a and 1b, participants were asked to rate the arousal and valence of both the message words and filler words. The filler words that best matched the message words in terms of the participants’ mean arousal and valence ratings were retained for the lexical decision task (LDT) in Study 2.
18 As the motor vehicle message was only paired with the social loss-frame message to assess the BIS in Study 2, words from the motor vehicle message were not compared with those words from the physical messages.
19 Mean word lengths were comparable between list types.
84 Study 1a: Evaluation of the four road safety messages
6.5 Method