Prueba de hipótesis específicas

Health messages are designed to persuade individuals to act in accordance with the recommendations within a message (Lewis et al., 2008a, 2009, 2010). Health messages focus on preventing injury and/ or promoting healthy behaviour by encouraging individuals to adopt safer, healthier attitudes and behaviour. They can be devised to reduce risky behaviours (e.g., risky driving behaviour), detect potential illnesses (e.g., cancer screening), or prevent future health problems (e.g., nutrition). Health messages may differ in frame (i.e., gain-framed or loss-gain-framed messages) and message types (i.e., social, physical, financial, or psychological).

32 3.2.1 Message framing

Health messages can be framed to focus on the negative consequences or punishment associated with a particular behaviour (i.e., loss-framed messages) or framed to focus on the positive consequences/ reward of that behaviour (i.e., gain-framed messages; Donovan &

Henley, 1997). For example, a loss-framed message may detail, “By not obeying the speed limits, you are increasing your risk of crashing and not protecting yourself and your loved ones.”, and the corresponding gain-frame focus would be, “By obeying the speed limits, you are decreasing your risk of crashing and protecting yourself and your loved ones” (Kaye et al., 2013). While identical information is conveyed in the loss-framed and gain-framed messages, message framing may influence individuals’ interpretations of the message and consequently, have different effects on persuasion (e.g., Meyerowitz & Chaiken, 1987; Millar

& Millar, 2000). One theory which has been applied to explain message framing effects is Prospect theory.

Prospect theory and message framing. Prospect theory was developed to explain how individuals make decisions in risky/ uncertain situations (Kahenman & Tversky, 1979, 1982; Tversky & Kahenman, 1981, 1992). Prospect theory states that decisions differ

depending on whether individuals are presented with information that focuses on losses (e.g., negative/ loss-framed messages) or information that focuses on gains (e.g., positive/ gain-framed messages). Specifically, the theory postulates that individuals are more likely to favour risky decisions when presented with losses and to avoid risky decisions when presented with gains (Kahenman & Tversky, 1982). Past research has applied this framing hypothesis to examine the influence that message frame (i.e., gain-framed vs. loss-framed messages) may have upon message persuasiveness and subsequent behaviour enactment (e.g., Meyerowitz & Chaiken, 1987; Rothman & Salovey, 1997; Rothman, Salovey, Antone,

Keough, & Martin, 1993).

33 Loss-framed health messages may be more persuasive when they focus upon

detection behaviours (i.e., messages that are developed to persuade individuals to seek early detection of potential health issues, such as skin cancer, mammography screening, and diabetes; Banks et al., 1995; Meyerowitz & Chaiken, 1987; Rothman & Salovey. 1997;

Rothman et al., 1993). Gain-framed messages, in contrast, may be more persuasive for preventative health behaviours (i.e., messages that focus on preventing future illness or injuries, such as exercise, dental hygiene, and healthy eating; e.g., Robberson & Rogers, 1988). Thus, in accordance with the framing hypothesis of Prospect theory, individuals prefer loss-framed messages when confronted with a potential risk (e.g., detection of illness) and gain-framed messages when risks are perceived to be unlikely (e.g., preventative health behaviour).

In Studies 1a, 1c, and 2, the message stimuli focused on safe driving behaviours, specifically, prevention/ reduction of speeding behaviour. According to the framing hypothesis of Prospect theory generally, gain-framed messages should be more persuasive than framed messages. However, previous research has reported that negative/ loss-framed road safety messages may be persuasive for some groups of drivers (e.g., Goldenbeld, Twisk, & Houwing, 2008; Lewis et al., 2007; Tay & Ozanne, 2002). For instance, Tay and Ozanne (2002) found that after exposure to threat-based anti-speeding, anti-drink driving, and seatbelt road safety campaigns, fatal crashes were significantly only reduced for females aged between 15-34 years and males aged between 35-54 years. Further, Goldenbeld et al. (2008) and Lewis et al. (2007) reported that female drivers were more likely to be persuaded by threat appeals than male drivers. These findings suggest that negative/ loss-framed messages may be more effective for particular groups of road users, in contrast to the framing

hypothesis of the Prospect theory. It should be noted that more recent reviews have also highlighted that additional factors, such as individual differences in approach and avoidance

34 systems (see section 3.4.1) may also moderate framing effects (e.g., Rothman & Updegraff,

2010; see also O’Keefe & Jensen, 2006, 2009).

While traditional road safety campaigns have relied heavily upon threat-based appeals (e.g., threat of loss of life; Donovan & Henley, 1997; Donovan, Jalleh, & Henley, 1999), more recent research has started to examine the potential effectiveness of gain-framed road safety messages (Lewis et al., 2008b, 2009). Lewis et al. (2008b), for instance, found that compared to loss-framed messages, gain-framed messages may be more effective at persuading certain groups of individuals, such as young males, to adopt safer driving behaviours. Thus, while loss-framed messages may be effective for some road users, other drivers may be more persuaded by framed messages. Study 2 included a range of gain-framed and loss-gain-framed anti-speeding messages to further examine the influence of message frame on message acceptance.

3.2.2 Message types

In addition to focusing on gain or loss, health messages can also be categorised according to whether they focus on social, physical, financial, or psychological threats (Donovan & Henley, 1997). Social threats, for instance, may emphasise the social

disapproval an individual may experience by not complying with the message, while physical threats may highlight the physical injuries that one may sustain by not complying with the message. Financial threats may emphasise the monetary costs associated with failing to act in accordance with the message, while psychological threats may focus on one’s self-esteem (Donovan & Henley, 1997). These threats can be expressed as gains (e.g., social approval or avoiding physical injuries for message compliance) or losses.

Consistent with previous research (e.g., Kaye et al., 2013; Schoenbachler & Whittler, 1996; Wiley, Krisjanous, & Hutchings, 2002), Studies 1a, 1c and 2 focused on two message types: physical and social themed messages. While social appeals have been implemented in

35 more recent Australian road safety campaigns, traditional physical threat messages have been

the predominant approach. Here crashes and injury/ death are often depicted as a consequence of unsafe driving behaviours (Tay & Watson, 2002). Similar to message framing effects, message type can also influence the persuasiveness of the road safety message (e.g., Goldenbeld et al., 2008; Lewis et al., 2008b, 2009). For instance, Goldenbeld et al. (2008) found that female drivers were more persuaded by physical threats than male drivers, while Lewis et al. (2008b, 2009) reported that male drivers may be more persuaded by messages that contained social cues. These findings suggest that while message type may influence message acceptance, gender may also be an additional factor to consider when developing the content of road safety messages.