Public service advertising

Public service advertising is a collective word for all kinds of activities and products that are used to improve road safety. The purpose of public service advertising is to achieve a voluntary and permanent change of knowledge, attitude or behaviour. In this case voluntary means that people voluntarily choose to perform the behaviour, as opposed to more repressive measures such as traffic enforcement (see also SWOV Fact sheet Traffic enforcement. It can still be about (abstaining from) behaviours which are prohibited by law, such as driving under the influence or exceeding the speed limit. In an information campaign various activities and products that form a coherent unity around a specific theme are used during a set period of time.

Public service advertising is organised at three levels: mass media (national or regional), local and personal.

Mass media level

In the recent past mass media information campaigns were organised rather randomly by various organisations (such as Dutch Traffic Safety Association (VVN) and the Dutch Association of Insurers). Today mass media campaigns often linked to enforcement and regional actions in specially planned campaign periods. This coherence is well-reflected in the campaign Daar kun je mee thuiskomen.

Local level

Examples of local information campaigns are campaigns in schools (see also SWOV Fact sheet Traffic education), and also activities at festivals where groups of people are addressed.

Personal level

This is one-to-one contact. For example, when a doctor informs a patient about the fitness to drive with certain medication. Likewise, when information staff address those present at meetings directly and have discussions with them, such as the organisation TeamAlert often does, this is called personal information.

There are different types of public service advertising (PSA). In relation with behaviour change Guttman [2] distinguishes three different possibilities.

First, PSA campaigns may focus on one’s own effectiveness and the prevailing social norm. Own effectiveness means that the campaign stresses that people are able to change their behaviour. Social standard means that the campaign shows that the desired behaviour is already shown by most others. For example, in choosing their own speed drivers are guided by the speed driven by other traffic rather than by the speed limit [3]. A PSA campaign could emphasize this social standard.

Second, PSA campaigns can make an appeal to emotions. Confrontational (or frightening) information, also known as fear appeals, confronts people in a hard, sometimes shocking way with the consequences of risky behaviour. In Australian television spots, for instance, this form is used  with shocking images of crashes, casualties and emotional relatives. However, there are also types of public service advertising that stress positive feelings and positive consequences of behaviour. This type of information is found to be more effective than fear appeals, particularly among men and young people [4].

Third, there are PSA campaigns that appeal to rational considerations and thus are purely informative and instrumental; for example, campaigns that give information and tips on transporting children in the car.

The effect of public service advertising (PSA) depends on how it is organised (mass media, local, private; see also the question 'How is public service advertising organised?') but also on the manner of approach.

Organisation

Many mass media campaigns combine information with police enforcement. In the Netherlands this combination has, among other things, led to increased use of seatbelts and child safety devices and increased use of bike lights [5] [6]. Likewise, the Goochem-campaign (about seatbelt use) and the Bob-campaign (about drink-driving) have been successful in changing attitudes and behaviour in a positive way [6]. Both campaigns have been qualified as 'best practice' in the SUPREME-manual and are used in a large number of European countries [7]. Also in other countries, such as Australia, New Zealand and the United States, the combination of police enforcement and information has been found to result in improved road safety [8].

International reviews conclude that PSA has a positive effect on road safety [9] [10]. However, as most PSA is combined with other activities (such as increased enforcement), there is little evidence for a stand-alone effect of mass media road safety information. A Dutch study [11] showed that a national PSA campaign on speed had no effect on measured speeds or offences. Places where the campaign was supported by special signs showed a small effect on the driven speeds, but this effect had disappeared a week after the signs were placed. Because of this minimal effect of isolated mass media? campaigns, most information activities in the Netherlands are supported by enforcement. This makes it very hard to determine whether the success of a campaign is the result of information, of enforcement, or of the combination of the two [12]. The little research that has tried to distinguish the effects concluded that the mass media information did not or barely contribute to improved traffic behaviour [13]. This does not mean that been information campaigns can be omitted. Information can indeed contribute to more knowledge and attitude change. It can also contribute to better acceptance of unpopular, but effective measures, such as enforcement.

TeamAlert, the foundation that provides traffic information for young people, mainly uses the local and personal approach. The target group is approached directly and in some projects the target group is approached individually. Various effect studies show that this approach is partially effective, particularly when it comes to increasing knowledge and behavioural intention (see for example effect measurements of the programmes ‘Kruispunt’  [14] and ‘Streetbeat’ [15]). However, change must be possible: for example, the evaluation of ‘Witte Waas’ (in which information about drugs and alcohol in traffic is given) indicated that the level of knowledge was already pretty high [16].

Manner of approach

The effect of public service advertising also depends on the approach. Informative, instrumental information can be effective in increasing knowledge, if the level of knowledge prior to the campaign is insufficient. Research by Goldenbeld [17] found that a campaign for the correct adjustment of the headrest in the car led to an improvement of the observed behaviour: before the campaign 40% had the headrest correctly adjusted; after the campaign, this was 60%.

As yet not much is known about the effects of information that specifically focuses on the social norm. However, there is research that shows that the social norm is important in demonstrating safe traffic behaviour. Young drivers, for instance, were more inclined to make a phone call while driving if they thought their friends supported this [18]. Drivers were also found to be guided more by other traffic in their speed choice than by the speed limit [3].

Evaluation studies of fear appeals find both positive and negative effects. Generally these effects only refer to changes in behaviour and behavioural intentions. The varied results make it difficult to determine whether fear appeals do indeed result in fewer crashes. Some campaigns were found to be effective, others were not.

+ Research from Australia and New Zealand shows that fear appeal media spots may have a positive effect: a reduction of unsafe traffic behaviour. According to the Australian research the number of road crash casualties declined by 5 to 7% as a result of the media spots [19] [20].

0 There are also road safety studies which found that fear appeals have no effect. A meta-analysis of 13 studies [21] for example, found no effect.

- Fear appeals having the opposite, negative effect, however, is also possible. This was the case with information campaigns on drink-driving [22], speed behaviour [23] [24], binge drinking [25] and on distraction in traffic [26]. A Dutch study found that the male subjects found speeding less dangerous after seeing a television spot. They were less willing to keep to the speed limit and downplayed the message ('speeding is dangerous') and the behavioural recommendation ('don’t drive fast, keep to the limit') [27]. Various Belgian studies indicate that although fear appeals have a short-lived effect on attitudes and opinions, the public quickly gets used to the element 'fear'. This would cause the effects to diminish more rapidly than the effects of information based on positive emotions [28].

Several factors determine the effectiveness of a public service advertising (PSA) campaign (see Figure 1). For example, an PSA campaign has a greater effect if the target group is more committed to the topic [29]. The effect is also greater if the campaign has a positive approach and focuses on new, relatively simple behaviour [30]. Social media (Facebook, Twitter) can strengthen the range and possibilities of a campaign. However, the use of social media can also have a negative effect due to an abundance of (uncontrolled) information [31]. According to a review by Wakefield et al. [32] the following factors increase the effect of a campaign:

• The use of multiple interventions simultaneously (for example, anti-smoking commercials combined with anti-smoking programmes in schools);
• A message aimed at one-time or irregular behaviour (e.g. the choice for vaccinations) and not at habitual behaviours (e.g. healthy eating or sports);
• Simultaneously offering products and services that support the behaviour change (e.g. providing a telephone number for questions);
• Improving the involvement of the target group (for example by providing information at times when people experience a major change (such as moving house, marriage, child birth) and their old behaviour is assessed; see also Schaalma et al. [30]).

The most important part of an information message are the behavioural recommendations. The risk behaviour is reduced most if the evoked emotions – both negative and positive – are combined with feasible and effective behavioural recommendations. This was demonstrated by, for instance, PSA campaigns about alcohol use in the traffic, smoking, and safe sex [33].

A behavioural recommendation is feasible if the target group believes that it can indeed be carried out. (' I can resist the temptation to drive fast on that stretch'). A behavioural recommendation is effective if the target group believes that the new behaviour is feasible and does indeed protect against danger ('I really have a smaller risk of a crash if I drive slower') [34] [35].

The attitude of the target group towards their own risk behaviour determines the effectiveness of (confrontational) information. The effect is greatest if people think their behaviour leads to an increased risk. But if people do not consider themselves vulnerable, they will not change their risk behaviour, despite the information about the consequences of the risk behaviour and behavioural recommendations [4] [36]. This principle, also called optimism bias, plays an important role, especially in the traffic (see for example Perrissol et al. [37]).

Figure 1. Effectiveness of PSA campaigns.

First, an effective public service advertising campaign must be well prepared. During preparation various points need to be checked:  the relationship between the behaviour that is to be changed and road safety, what can change the behaviour, which target group shows the behaviour, and whether this target group can be reached with the campaign [12]. After the preparation the target groups are chosen and the campaign strategy is worked out. The campaign should contain a clear behavioural recommendation [38]. This means that the message in the campaign must be the desired behaviour, and not the unwanted behaviour. Not the message: "If you drink then drive, you are a bloody idiot", but: "100% BOB, 0% op" (“if you are the designated driver, you drink no alcohol at all”)

In the CAST manual, the result of the EU project CAST – Campaigns and Awareness-raising Strategies in Traffic Safety – Delhomme et al. (2009) explain how a campaign should be developed and evaluated. Part I of this manual presents an overview of theories on public information and communication. Part 2 describes how a successful campaign should be developed, executed and assessed; it moves from starting the campaign to situation analysis, to designing the campaign, to designing the assessment and then to reporting on the project. Nathanail & Adamos (2013) also discuss the various possibilities for a thorough scientific evaluation of a road safety campaign, including the theoretical conceptual framework, the research design and the different variables that are to be measured.