**5. Content and delivery of mass media campaigns**

Several aspects of mass media campaigns may influence their effectiveness. These can be categorized into variables related to message content and to message delivery.

#### **5.1 Message content**

One important aspect of message content involves the themes used to motivate the desired behavior change. Some common motivational themes in mass media campaigns to prevent unhealthy behabiours include:


The actions promoted by the campaigns also vary, ranging from messages related to abstinence or moderation to more specific behavioural recommendations. Decisions related to message content are generally made based on the opinions expressed by experts or focus groups rather than on evidence of effectiveness in changing behaviour (Randy et al., 2004).

Another aspect of message content relates to the optimal amount of anxiety produced (Witte & Allen, 2000; Tay, 2002). The effectiveness of "fear-based" campaigns is the subject of a long-standing controversy. Some level of anxiety arousal is generally seen as a desirable motivator. However, several authors have cautioned that generating intense anxiety by emphasizing the severity of a problem and the audience's susceptibility to it can cause some people to ignore or discount the campaign messages. Although this caution appears to be justified, increasing the strength of a fear appeal also increases the probability that the audience will change their attitudes, intentions, and behaviours. These changes are maximized, and defensive avoidance minimized, when the anxiety-arousing message is accompanied by specific information about actions that people can take to protect

The Role of Mass Media Communication in Public Health 409

What has been missing from these previous reviews is a systematic analysis of the size of effects achieved for different types of objectives, e.g., awareness, knowledge, attitudes, and behaviors. It was addressed this gap by identifying and reviewing the extant empirical data

**Campaign Objective Average Size of Change %** 

Changing behaviour is the highest priority in any public health campaign, however, most of

Theoretically, the mass media are supposed to be most effective in achieving awareness. This review supports that expectation. When measuring awareness as simple recognition of the message, up to 83% levels of awareness have been reported, with a median of 48%. Although, without a pre message measure, some of this (perhaps up to 9%) may be

Ceiling effects must also be considered. If awareness is moderately high before the campaign, there are ceilings on the increases possible and probably these increases are harder to achieve. If both pre and post levels of awareness are available, increases can be calculated based on the percent of audience possible to change. For example, if awareness of the seriousness of colon cancer was 11% prior to a campaign and 40% after it, the increase,

Knowledge gain is clearly achievable using mass mediated health campaigns. When exposure is guaranteed, dramatic increases in knowledge (as large as 60%) have been observed. When exposure is not guaranteed but the campaign can saturate a community, knowledge gains around 25% seem feasible. The size of these knowledge gains decrease when the campaigns are national in scope and must compete with numerous other stimuli. Still, most of the campaigns were successful in achieving some knowledge gain, although around 10% appears to be a more achievable increase. Multi—channel campaigns appear to

Below there is some evidence about changes in levels of knowledge and awareness during

Changes in levels of tolerance: those in the general public who say that homosexual

the mass media will change knowledge and awareness more easily than behaviour.

instead of being 29% would be 29% of the possible change of 89% which is 33%.

be much more successful than single channel, especially print only campaigns.

Awareness of 'sensible drinking message' unit – up from 39 to 76%, 1989–94

People's accurate assessment of their own drinking – up 5%, 1990–94.

relations are always or mostly wrong – 74% in 1987; 44% in 1997

Knowledge of units in popular drinks – up 300%, 1989–94

Awareness (N=16) 56 Knowledge change (N=15) 22 Attitude change (N-21) 8 Behavior change (N=29) 13

Table 3. Average changes achieved after mass-mediated health campaigns

from evaluations of mass mediated health campaigns.

**6.1 Changing knowledge and awareness** 

mass media public health campaigns:

Alcohol

HIV/AIDS

measurement error, e.g., a desire to please the interviewer.

themselves. The degree of persuasion versus defensive avoidance produced may be influenced by interactions between the message content and characteristics of the recipient. For instance, strong fear appeals may be more effective for motivating a response among segments of the audience that initially do not view the problem addressed as being important or relevant to them. They may also be more persuasive to people who are already engaging in the desired behaviour.

#### **5.2 Message delivery**

A mass media campaign cannot be effective unless the target audience is exposed to, attends to, and comprehends its message. Two important aspects of message delivery are control over message placement and production quality. Control over message placement helps to ensure that the intended audience is exposed to the messages with sufficient frequency to exceed some threshold for effectiveness.

It also allows for the optimal timing and placement of those messages. This control can only be assured with paid campaigns. Those that rely solely on donated public service time may attain adequate exposure, but message placement and frequency are ultimately left to media schedulers and station management; paid advertising time always gets preferential placement. Assuming that the target audience is adequately exposed, high production quality of the campaign messages may maximize the probability that the audience will pay attention to them. High production quality may also improve the chances of eliciting the intended emotional impact.

#### **5.3 Message pretesting**

Pretesting of campaign themes and messages is also thought to be important for a successful outcome (Hornik & Woolf, 1999). Pretesting can help to assess which themes or concepts are most relevant to the target audience. It can also help to ensure that the target audience will attend to and comprehend the specific messages presented. The importance of pretesting is highlighted by an evaluation of a mass media campaign designed to prevent alcohol-related problems by encouraging drinking in moderation. No pretesting of ads was done for this campaign, and a survey conducted at midcampaign found that over a third of respondents thought that the ads were promoting alcohol consumption. Many mistook them for beer ads.

#### **6. Effectiveness of the mass media campaigns**

An Australian review of mass media health promotion campaigns in two areas, cardiovascular risk behavior and safety restraints (Redman, Spencer, and Sanson-Fisher, 1990) illustrates these moderate effects. The authors began with 24 studies but determined that only nine met their criteria for adequate evaluation methodologies. These nine were further divided into two models of media effects: media only and media as agenda-setting plus community programming. Not surprisingly, they concluded that media only campaigns had discouraging results but that most studies of media plus intensive community interventions reported significant changes in behavior. The authors, however, challenged these positive results by questioning how important the media component was to the success of such combined programs.

It is probably time to consider a fourth era and that one is characterized by the use of the internet and by paid media rather than relying on public service time. It is too early to have much data from this fourth era but the White Houses' Office of the Drug Czar's anti-drug campaign shows some promising results as do many of the state anti-smoking campaigns.

themselves. The degree of persuasion versus defensive avoidance produced may be influenced by interactions between the message content and characteristics of the recipient. For instance, strong fear appeals may be more effective for motivating a response among segments of the audience that initially do not view the problem addressed as being important or relevant to them. They may also be more persuasive to people who are already

A mass media campaign cannot be effective unless the target audience is exposed to, attends to, and comprehends its message. Two important aspects of message delivery are control over message placement and production quality. Control over message placement helps to ensure that the intended audience is exposed to the messages with sufficient frequency to

It also allows for the optimal timing and placement of those messages. This control can only be assured with paid campaigns. Those that rely solely on donated public service time may attain adequate exposure, but message placement and frequency are ultimately left to media schedulers and station management; paid advertising time always gets preferential placement. Assuming that the target audience is adequately exposed, high production quality of the campaign messages may maximize the probability that the audience will pay attention to them. High production quality may also improve the chances of eliciting the

Pretesting of campaign themes and messages is also thought to be important for a successful outcome (Hornik & Woolf, 1999). Pretesting can help to assess which themes or concepts are most relevant to the target audience. It can also help to ensure that the target audience will attend to and comprehend the specific messages presented. The importance of pretesting is highlighted by an evaluation of a mass media campaign designed to prevent alcohol-related problems by encouraging drinking in moderation. No pretesting of ads was done for this campaign, and a survey conducted at midcampaign found that over a third of respondents thought that the ads were promoting alcohol consumption. Many mistook them for beer ads.

An Australian review of mass media health promotion campaigns in two areas, cardiovascular risk behavior and safety restraints (Redman, Spencer, and Sanson-Fisher, 1990) illustrates these moderate effects. The authors began with 24 studies but determined that only nine met their criteria for adequate evaluation methodologies. These nine were further divided into two models of media effects: media only and media as agenda-setting plus community programming. Not surprisingly, they concluded that media only campaigns had discouraging results but that most studies of media plus intensive community interventions reported significant changes in behavior. The authors, however, challenged these positive results by questioning how important the media component was

It is probably time to consider a fourth era and that one is characterized by the use of the internet and by paid media rather than relying on public service time. It is too early to have much data from this fourth era but the White Houses' Office of the Drug Czar's anti-drug campaign shows some promising results as do many of the state anti-smoking campaigns.

engaging in the desired behaviour.

exceed some threshold for effectiveness.

**6. Effectiveness of the mass media campaigns** 

to the success of such combined programs.

**5.2 Message delivery** 

intended emotional impact.

**5.3 Message pretesting** 

What has been missing from these previous reviews is a systematic analysis of the size of effects achieved for different types of objectives, e.g., awareness, knowledge, attitudes, and behaviors. It was addressed this gap by identifying and reviewing the extant empirical data from evaluations of mass mediated health campaigns.


Table 3. Average changes achieved after mass-mediated health campaigns
