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Evaluation of the National Youth Anti-Drug Media Campaign - Executive Summary

The number one goal of The National Drug Control Strategy is to “Educate and enable America’s youth to reject illegal drugs as well as alcohol and tobacco.” One of the objectives in support of that goal includes, “Pursue a vigorous advertising and public communications program dealing with the dangers of drug… use by youth.” Under the Treasury-Postal Appropriations Act of 1998, Congress approved funding (P.L. 105-61) for “a national media campaign to reduce and prevent drug use among young Americans.” Pursuant to this act, the Office of National Drug Control Policy (ONDCP) launched the National Youth Anti-Drug Media Campaign (the Media Campaign).

This program has progressed through three phases of increasing complexity and intensity. Phases I and II are not discussed in this report. ONDCP has available other reports that evaluate those phases. This report focuses on Phase III, which began in September 1999 and is planned to run at least to spring 2002. An evaluation of Phase III is being conducted under contract to the National Institute on Drug Abuse (NIDA) by Westat and its subcontractor, the Annenberg School for Communication at the University of Pennsylvania. Funding of the evaluation is provided by ONDCP from the appropriation for the Media Campaign itself. This is the third semiannual report of the Westat and Annenberg evaluation of Phase III of the Media Campaign.

Highlights from the Third Semiannual Report include:

  1. A brief description of the Media Campaign’s activities to date;
  1. A review of the logic and approach of the evaluation;
  1. Statistics on the level of exposure to messages achieved by the Media Campaign in the first 9 months of Phase III; and
  1. A description of baseline behaviors, beliefs, attitudes, and intentions of both parents and youth. These descriptions focus on the outcomes that will be monitored over time for possible changes that might be brought about by the Media Campaign.

This report from the Westat and Annenberg evaluation presents a first round of measurement. It includes early estimates of exposure to the Media Campaign, and it identifies anti-drug beliefs and drug use behaviors that will be watched over time both for movement and for their association with exposure. It thus sets the stage for the evaluation. This report contains no findings about the effectiveness of the Media Campaign. Such findings after only 9 months of operation of Phase III of the Media Campaign would be premature. This reflects both substantive and technical concerns. From the substantive perspective, effects are expected to be achieved and measurable after a longer period of Media Campaign operations. From the technical perspective, there would be little confidence in inferences from a simple cross-sectional analysis, without even accompanying evidence for change over time in outcomes.

The first report on tentative analyses of effects will be issued after the next wave of data collection in March 2001. At that time, there will be some evidence presented about changes, if any, in outcome measures like the cognitive variables of interest such as beliefs about the consequences of marijuana use at least once or twice in a lifetime. This evidence about change will be complemented by evidence about association of exposure with the outcome measures. However, it is possible that Media Campaign-produced change will take longer to achieve and/or to detect. Indeed, conclusive evidence will take several years to accumulate and analyze. The final report is scheduled for March 2004. At that time, the sample youth and their parents will have been studied for 3 to 4 years.

This report by Westat and Annenberg provides six types of information:

  • A brief update and description of the Media Campaign’s activities to date;

  • A review of the logic and approach of the evaluation;

  • Statistics on the level of exposure to messages achieved by the Media Campaign during Phase III;

  • Evidence for change in the drug use behaviors of youth between Wave 1 and Wave 3, with an average elapsed time between measures of about 12 months.

  • Preliminary evidence for Campaign effects on youth. This includes evidence for association between exposure to the Campaign and beliefs, attitudes, and intentions, with statistical controls for confounders and evidence of change between the first and third waves of data collection on these outcomes. In addition, there is analysis of change and associations among subgroups of the population.

  • Preliminary evidence for Campaign effects on parents. It includes a presentation of evidence for association between exposure to the Campaign and parents’ talk about drugs with their children, their monitoring of their children’s behavior, and their engaging in fun activities with their children, as well as their beliefs and attitudes about talk and about monitoring. It also includes evidence for change between Waves 1 and 3 in these outcomes. Also, both change and association data is reported for some subgroups of the population.

Background on the Media Campaign

The Media Campaign has three goals:

  • Educate and enable America's youth to reject illegal drugs;

  • Prevent youth from initiating use of drugs, especially marijuana and inhalants; and

  • Convince occasional users of these and other drugs to stop using drugs.

The Media Campaign originally targeted paid advertising to youth aged 9 to 18 (with a current focus on youth 11 to 17), parents of youth in these age ranges, and other influential adults. Phase III advertising is being disseminated through a full range of media or “channels” following a Communications Strategy developed by ONDCP. Phase III also includes components other than advertising. There are outreach programs to the media, entertainment, and sports industries, as well as partnerships with civic, professional, and community groups. These other components, which are being coordinated by a public relations firm, include encouraging entertainment programs with anti-drug themes, coverage of the anti-drug campaign in the news media, community activities, corporate co-sponsorship, and special interactive media programming.

ONDCP performs overall management of the Media Campaign in collaboration with the following groups:

  • The Partnership for a Drug-Free America (PDFA), which provides the creative advertising for the Media Campaign through its existing pro bono relationship with leading American advertising companies;

  • A Behavioral Change Expert Panel (BCEP) of outside scientists who help to inform the content of the advertisements to reflect the latest research on behavior modification, prevention, and target audiences;

  • Ogilvy, a national advertising firm, which organizes and executes media buying, carries out some supportive research, assures a coherent advertising strategy, and conducts day-to-day management of the Media Campaign

  • Fleishman-Hillard, a public relations firm, which coordinates the nonadvertising components of the Media Campaign; and

  • The Ad Council, a coordinator of national public interest advertising campaigns, which supervises distribution of donated advertising time to other public service agencies under the “pro bono match” program.

For Phase III, advertising space is purchased on television, radio, newspapers, magazines, billboards, transit ads, bus shelters, movie theaters, video rentals, Internet sites, Channel One broadcasts in schools, and other venues as appropriate. The television buys include spot (local), network, and cable television. One of the requirements in the Media Campaign appropriations language is that each paid advertising slot must be accompanied by a donation of equal value for public service messages from the media, known as the pro bono match. The pro bono match involves one-to-one matching time for public service advertisements or in-kind programming. The pro bono spots may include other themes including anti-alcohol, anti-tobacco, and mentoring, but such themes are not part of the paid advertising.

Methodology

The report presents results from three waves of an in-home survey covering youth aged 9 to 18 years and their parents. While the focus of the Campaign is on youth older than age 10, the inclusion of 9- and 10-year-old children for initial interviews provides a sample of those who will age into the primary target audience and who will be followed for 2 to 3 years. Wave 1 included 3,312 youth from 9- to 18-years-old and 2,293 of their parents, undertaken between November 1999 and May 2000; Wave 2 included 2,362 youth and 1,632 of their parents interviewed between July and December 2000. Wave 3 included 2,459 youth and 1,681 of their parents interviewed between January and June 2001. These respondents represent the approximately 40 million youth and 43 million of their parents who are the target audience for the Media Campaign. The name of this survey is the National Survey of Parents and Youth (NSPY).

NSPY was designed to represent youth living in homes in the United States. Sampling of eligible youth was designed to produce approximately equal-sized samples within three age subgroups (9 to 11, 12 to 13, 14 to 18). One or two youth were randomly selected from each eligible sample household. One parent was randomly chosen from each eligible household. A second parent was drawn in the rare event where the two sample youth were not siblings.

The interviewers for NSPY achieved a response rate of 65 percent for youth and 63 percent for parents across Waves 1 to 3, with little variation across waves. Final estimates are adjusted for nonresponse and for differences with known population characteristics, with confidence intervals accounting for the complex sample design.

NSPY questionnaires were administered in respondents’ homes on touch-screen laptop computers. Because of the sensitive nature of the data to be collected during the interviews, a Certificate of Confidentiality was obtained for the survey from the Department of Health and Human Services, and confidentiality was promised to the respondent. All sensitive question and answer categories appeared on the laptop screen and were said to the respondent in a recorded voice over headphones that could be heard only by the respondent. The responses were chosen by touching the laptop screen.

The NSPY questionnaire for youth included extensive measurement of their exposure to Media Campaign messages and other anti-drug messages. It also included questions about their beliefs, attitudes, intentions, and behaviors with regard to drugs and a wide variety of other factors either known to be related to drug use or likely to make youth more or less susceptible to Media Campaign messages.
The NSPY questionnaire for parents also included measures about exposure to Media Campaign messages and other anti-drug messages. In addition, it included questions about parents’ beliefs, attitudes, intentions, and behaviors with regard to their interactions with their children. These included talk with their children about drugs, parental monitoring of children’s lives, and involvement in activities with their children.

Ad exposure was measured in NSPY for both youth and parents by playing current or very recent TV and radio advertisements for respondents on laptop computers to aid their recall. Youth were shown or listened to only youth-targeted ads and parents were shown or listened to only parent-targeted ads. In addition, there were some nonspecific questions about recall of ads seen or heard on TV and radio, and in other media such as newspapers, magazines, movie theaters, billboards, and the Internet.

Media Purchases and Evidence about Exposure

Media Purchases

Across its multiple media outlets, the Media Campaign reports that it purchased enough advertising time to achieve an expected exposure to 2.7 youth-targeted ads per week for the average youth and to 2.3 parent-targeted ads per week for the average parent, over the 95-week period covered by this report (September 1999 through June 2001). These estimates include Campaign advertisements intended for either general market youth or general market adults; they do not include exposure by youth or parents to advertisements intended for other audiences, often called “spill.”

  • Across the three periods of measurement of the Campaign, the patterns of total purchased exposure were more stable for youth than for parents. Figures ES-1 and ES-2 present the weekly totals for expected purchased exposures, where 100 means that the average person in the audience would be exposed once per week. Both the actual media purchases and a smoothed line averaging over 3-week periods are presented. Figure ES-1 shows that youth buys were stable across Wave 1,

    except for a planned reduction during the summer of 2000, rose during the first half of Wave 2, and remained fairly high during Wave 3 with a slow decline. Table ES-1 shows that this produced average expected weekly exposures of 2.5, 2.6, and 2.9 across the three waves for youth.

  • Figure ES-2 shows parent-purchased exposures had much more variation. Wave 1 purchases were comparable to those for youth, but declined sharply during Wave 2, particularly at the end of 2000. They began a return to former levels during Wave 3, with the mean weekly purchased exposures at 2.8, 1.5, and 2.4 presented in Table ES-1.

  • Media purchases, as reported by Ogilvy, the media buyer for the Media Campaign, were made both in channels that reached a wide audience (like network, spot television, and radio) and in channels that reached fewer individuals. For adults, averaged across the three waves, about half of the primary media buys were in potentially wider-reach media (network radio (28% of all expected exposures), network television (23%)) and half were in narrower-reach media (outdoor media (32%), magazines (11%), newspapers (4%), the Internet, and movie ads (1%)). For youth, the primary media buys were more weighted toward wider reach media with network television (22%), network radio (19%), spot buys of radio (9%), and spot buys of television (11%) totaling 61 percent of all buys, with 39 percent on narrower reach media: in-school television (17%), in magazines (9%), the Internet (3%), basketball backboards (5%), arcades (2%), and nontraditional media (3%).

  • Media purchases for youth were balanced between wider- and narrower-reach media in a stable pattern across waves. For parents, media purchases during Wave 1 and Wave 3 were comparable in their balance between wide- and narrow-reach media. However, the Wave 2 decline in purchases was greater for the narrower reach media (down 60% at Wave 2 from the Wave 1 level) than the wider reach media (down 29% from the Wave 1 level). However, the absolute decline in weekly exposures was substantial in both types of channels. (See Table ES-1.)

Table ES-1. Expected Targeted Exposures per week purchased for
youth and adults across waves by reach of the channels
- - Expected weekly exposures
( percent of all exposures)
Reach Wave 1 Wave 2 Wave 3
Youth Wider reach channels
(network, cable and spot TV, network and spot radio)
1.54
(59%)
1.59
(63%)
1.76
(60%)
Narrower reach channels
(magazines, movies, Internet, in-school TV, etc. )
1.05
(41%)
.95
(37%)
1.16
(40%)
Total per week 2.59 2.54 2.92
Adults Wider reach channels
(Network and cable TV, network radio)
1.33
(48%)
.95
(63%)
1.10
(46%)
Narrower reach channels
(newspapers, magazines, outdoor media, Internet, movies)
1.42
(52%)
.57
(37%)
1.30
(54%)
Total per week 2.75 1.52 2.40

Recall of Exposure

NSPY used two measures of exposure; the first is based on general recall of seeing anti-drug ads through all media, with the second based on specific recall of currently broadcast ads on television and radio.

  • General exposure recall to all anti-drug advertising was fairly stable for parents and for youth across the three waves. This stability occurred despite the variation in purchases of targeted advertising by the Campaign. These general exposure measures, which may include exposure to advertising targeted to the other audience and advertising placed by other institutions, did not appear to relate closely to changes in Campaign-targeted buys across the three waves. About 71 percent of all adults and 73 percent of all youth recalled weekly exposure to any anti-drug ads (Table ES-2).

  • Specific recall of Campaign ads among parents and youth reflected the changes in television and radio purchases across waves. For parents, specific recall of television ads declined by one-sixth (from 25% to 21%) between Waves 1 and 3. The decline in media purchases in Wave 2 was extended into an effect on recall in Wave 3 despite the increasing purchases during that wave (Table ES-2). Specific recall of radio advertising among parents during the first two waves sharply increased during Wave 3.

  • Specific recall of Campaign ads for youth aged 12 to 18 increased significantly from 35 percent in Wave 1 to 41 percent in Wave 3. The increase in media purchases for youth across the three waves translated into small increases in reports of television exposures between the first two waves and a sharp increase for the third wave (Table ES-2). Youth also reported a sharp increase between Waves 2 and 3 in their recall of the radio ads, although it remained much lower than television ad recall.

Table ES-2. Change in Exposure to Campaign Advertising Across Waves
Population Exposure Measure: percent seeing/hearing ads 1 or more times per week Wave 1
(%)
Wave 2
(%)
Wave 3
(%)
Parents General Exposure: Across all media 71 71 72
Specific Exposure: TV ads 25 22 21*
Specific Exposure: radio ads 10 10 17*
Youth 9 to 11 General Exposure: Across all media 64 61 63
Specific Exposure: TV ads 30 32 36*
Youth 12 to 13 General Exposure: Across all media 74 78 76
Specific Exposure: TV ads 40 43 51*
Specific Exposure: radio ads NA 4 10*
Youth 14 to 18 General Exposure: Across all media 77 79 77
Specific Exposure: TV ads 34 37 47**
Specific Exposure: radio NA 4 13**
* Significant change between Waves 1 and 3, p<0.05.
** Significant change between Waves 2 and 3, p<0.05.

1
Respondents during Wave 3 were interviewed throughout the January to June 2001 period; the decline in media purchases was particularly sharp during the final 6 weeks of the Wave 2 period and only gradually climbed back during Wave 3. Study participants were asked about exposure to messages in the months previous to the interview. As a result, the effects of decreasing purchases in Wave 2 were only beginning to be seen for respondents during Wave 2 and were still affecting early Wave 3 respondents. Increasing purchases toward the last half of Wave 3 would not have affected many of the respondents interviewed in the first half of the Wave (see Figure ES-2).

NA: Radio use not measured for 9- to 11-year-olds at all and not for other youth during Wave 1.

“Brand” Recall

One of the innovations of Phase III has been the inclusion of a Campaign “brand.” A brand is used in many advertising campaigns to provide a recognizable element to coordinate advertising as well as nonadvertising components of the campaign. Insofar as the brand is recognized and positively regarded, its familiar presence may create some initial positive response to any new ad or increase the perception that each ad is part of a larger program. Such effects may, in turn, influence acceptance of the Campaign’s message.

The NSPY started measurement of brand recall in Wave 3. The data provide evidence for brand learning, particularly among youth:

  • Approximately 60 percent of the 12- to 18-year-olds who were asked reported recall of the Campaign brand for youth and 46 percent of the parents recalled the Campaign brand targeted at parents. Because some of the claimed recall could have been due to false recollection, true recall cannot be precisely estimated at this time.

  • There is good evidence that brand recall is associated with exposure to the Campaign. For instance, when one examines the specific exposure recall measure, 33 percent of youth in the lowest exposure group said they recognized the brand, while 79 percent of the highest exposure group did so. For parents, 36 percent of the lowest exposure group and 65 percent of the highest exposure group recalled the brand phrase.

The Internet

The data confirm that Internet use is very high and increasing among 12- to 18-year-olds and even among parents, but a small percentage of youth or parents recall exposure to anti-drug information on the Internet.

  • There were no statistically significant changes between waves in visits to sites where anti-drug information is to be found (“anti-drug sites”) by youth. A close to constant 10 percent or less of youth have visited such anti-drug sites anytime in the past 6 months. Around 5 percent indicate that they have visited pro-drug sites.

  • Parents increased their use of the Internet in the past 6 months from 60 percent at Wave 1 to 70 percent at Wave 3. There was more use of parenting-skill sites (7% to 10%) and anti-drug sites (6% to 9%).

Exposures to Other Drug Messages

Both youth and parent audiences receive messages about drugs from other sources besides Media Campaign paid advertising. Those other sources of messages are themselves the target of Campaign efforts, and they also create a context for receiving the purchased anti-drug media messages. Exposure to messages through these other public sources remains high, but, with a few exceptions, there was not much change in them between waves (Table ES-3).

Table ES-3. Change in Exposure to Drug-Related Communication Across Waves
Population Exposure Measure Wave 1
(%)
Wave 2
(%)
Wave 3
(%)
Youth 9 to 11 Percent in-school drug education past year 55 56 55
Percent extracurricular drug education past year 8 8 7
Percent weekly exposure to stories on at least one medium with drugs and youth content 45 47 45
Youth 12 to 18 Percent in-school drug education past year 67 66 65
Percent extracurricular drug education past year 8 7 6*
Percent weekly exposure to stories on at least one medium with drugs and youth content 52 53 53
Parents Percent weekly exposure to stories on at least one medium with drugs and youth content 65 62 65
Percent hearing a lot about anti-drug programs in community in past year 32 36 32
Percent hearing a lot about drug-related referenda in past year 6 9 9*
Percent attending drug prevention programs in past year 29 32 30
Percent attending parent effectiveness programs in past year 29 31 30
* Significant between Wave1 and Wave 3 change, p<0.05.

The Campaign’s focus in working with youth-serving organizations and parent groups is to integrate drug use prevention messages and strategies into their existing educational programs and extracurricular activities, rather than to increase participation in anti-drug programs per se. With regard to youth and parent involvement in such programs:

  • Most youth report having attended anti-drug education in school during the past year, but this remained unchanged through the three waves. Out-of-school drug education was much rarer, around 7 percent of all youth reported it, and was declining across the three waves.

  • A little less than one-third of parents reported attending anti-drug and parental effectiveness programs. This did not change across waves.

Regarding recall of public drug-related discussions and mass media stories:

  • Parent reports indicate little statistically significant change in recall of community-level drug-related discussion or programs. The only exception was an increase in the proportion that had heard a lot about drug-related referenda in the past year (from 6% in Wave 1 to 9% in Waves 2 and 3.)

  • More than half of parents and youth reported weekly exposure to mass media stories about drugs and youth. There was little change in this across waves.

Drugs are not only a public topic; they are also a common topic for private conversation between parents and children, and among youth and their friends (Table ES-4). Parents reported a stable level of conversations about drugs with their children across waves; around three-quarters of them claimed to have two or more conversations with their children about drugs in the previous 6 months. Youth reported lower levels of conversation with their parents (closer to one-half recalled two or more conversations in the previous 6 months). Also, fewer of the younger children (9 to 11 and 12 to 13) reported such conversations at Wave 3 than at Wave 1.

  • Most youth have conversations about drugs, and many of them have such conversations frequently. The partners for such conversations shift sharply as youth mature. As youth mature, they are less likely to talk with their parents and more likely to talk with friends. (See Table ES-4.)

Table ES-4. Change in drug-related conversations across waves
Percent with two or more conversations in past 6 months
Population Wave 1
(%)
Wave 2
(%)
Wave 3
(%)
With friends Youth 9 to 11 29 23 28
Youth 12 to 13 44 44 39*
Youth 14 to 15 69 52 65
Youth 16 to 18 68 71 70
With parents Youth 9 to 11 63 57 50*
Youth 12 to 13 59 56 53*
Youth 14 to 15 58 52 53
Youth 16 to 18 48 52 45
With children Parents of 9 to 11 71 72 74
Parents of 12 to 13 80 78 81
Parents of 14 to 15 82 79 82
Parents of 16 to 18 78 80 83
* Between Wave 1 and Wave 3 change significant at p<0.05.

  • In the course of conversation about drug use, young people of all ages discuss negative things about drugs; but many older youth also speak positively about drugs. For 12- to 13-year-olds, conversations with the theme “marijuana use isn’t so bad” occurred for only 9 percent of the respondents, at about one-fifth the rate (45%)for conversations about “bad things that happen if you use drugs.” Among 16- to 18-year-olds, the pro-marijuana conversations are reported by 34 percent of the respondents, about three-fifths (55%) as often as discussions of the bad things that can happen if you use drugs . There was no substantial change in the balance of “pro-drug” to “anti-drug” comments between waves.

Estimates of Youth Drug Use

Following the goals of the Media Campaign given earlier, NSPY was designed to assess the influence of the Media Campaign on initial use (i.e., using at least once in a lifetime) and the shift from initial to regular use (i.e., using at least 10 or more times in a year) of marijuana and inhalants. NSPY includes questions about drug use primarily so that the correlations of cognitive variables (such as beliefs, attitudes, social norms, self-efficacy, and intentions) with actual usage can be studied. NSPY was also designed to measure linkages in a theoretical model for Media Campaign action: linkages between ad exposure and attitudes, between attitudes and intentions, and between intentions and actions (drug use).
Because it has a larger sample and a long trend line, another survey sponsored by the Federal Government—Monitoring the Future (MTF) study—provides better measurements of change in drug use behaviors.

  • The 2001 MTF data are not yet available; the most recent MTF data, showing a fairly stable pattern of marijuana use since the start of Phase III, were included in the previous report.

  • The NSPY comparisons between Wave 1 and Wave 3, although based on smaller samples, show continuing stability in drug use through June 2001 (Table ES-5).

Table ES-5. Use of marijuana by age (NSPY reports)
` Percent Marijuana Use in the Past Year*
Age Group Wave 1
11/99 to 6/00 (%)
Wave 2
7/00 to 12/00 (%)
Wave 3
1/01 to 6/01 (%)
9 to 11 0.8 0.0 0.3
12 to 13 3.3 3.2 2.0
14 to 15 11.2 11.5 14.4
16 to 18 28.9 29.3 27.6
12 to 18 15.9 15.8 15.6
* No statistically significant changes across waves.

Campaign Effects

The balance of this Executive Summary presents evidence obtained to date regarding Campaign effects. The discussion first summarizes the logic adopted for claiming effects based on the cross-sectional data collected in the initial three NSPY waves. It then presents the findings regarding Campaign effects on youth followed by the finding for Campaign effects on parents.

The Logic of Claiming Campaign Effects

The report provides an analysis of preliminary Campaign effects. The analysis involves two components: examining change and examining how exposure to the Campaign is associated with outcomes. If the Campaign has been successful, it would be desirable to see positive change in the outcomes. However, change over time in outcomes (or a lack of change despite good Campaign effects) may be due to other influences besides the Campaign. Thus, if effects are to be attributed to the Campaign, there ought to be an association between exposure to Campaign messages and the outcomes.

However, evidence of the presence or absence of an association will not be sufficient ground for making a definitive decision about whether effects have occurred. A positive association may be due to the influence of other variables on both exposure and outcomes. This threat to inference can be substantially lessened by statistical controls as described below. An association observed in cross-sectional data may also reflect the influence of the outcome variable on (recall of) exposure. This threat of ambiguity of causal direction is more difficult to reject until longitudinal data are in hand, and it is possible to establish time order between variables—that is, to examine whether a prior state on exposure affects change over time in the outcome measure.

There is another constraint as well. The analysis considers only immediate direct effects of exposure on individuals. An association between exposure and outcomes is expected only if individuals personally exposed to Campaign messages learn and accept those messages in the short term. Future reports will examine effects that occur through other routes, including those mediated through parents or other social networks or through institutions. It will also be possible to look at delayed effects.

For youth, the analysis is limited to nonusing 12- to 18-year-olds and concerns their attitudes, beliefs, and intentions (“cognitions”) about possible initiation of marijuana use in the subsequent year. There were not enough occasional users (i.e., those using it one to nine times in the past year) among the youth to examine Campaign effects on their cognitions related to regular use. The parent analysis includes all parents and focuses on the target parenting behaviors (and their supporting cognitions) including talk, monitoring, and engaging in fun projects or activities with their children in or out of the home.

All analyses of associations between exposure to Campaign messages and outcomes use a method called “propensity scoring” to control for the possible influence of a very wide range of possible confounding variables. The analyses began with tests for any pre-existing differences among the exposure groups on a large number of variables. The parent analyses were corrected, among other factors, for observed differences on race, ethnicity, gender, age of parent, income, marital status, strength of religious feelings, age of children, neighborhood characteristics, media consumption habits, language, and parental substance use (alcohol, tobacco, marijuana, and other illegal drugs). The analyses of youth associations were further controlled for any pre-existing difference among exposure groups on school attendance, grade level, academic performance, participation in extra curricular activities, plans for the future, family functioning, personal antisocial behavior, association with antisocial peers, use of marijuana by close friends, personal tobacco and/or alcohol use of a long-standing nature, and sensation-seeking tendencies.

The second semiannual report found some ambiguous evidence about Campaign effects. It found a positive trend from Wave 1 to Wave 2 for youth, but little pattern of association. Contrarily, it found no significant trends for parents, but did find significant associations between Campaign exposure and target outcomes. Of the two, the evidence for parents was more promising. This report provides new information for both audiences.

For youth, the positive trends were not maintained in Wave 3; indeed, the levels on the primary outcome variables regressed so that they were no longer different from the Wave 1 levels. There was still no pattern of significant association between exposure and target outcomes for youth. The parents’ results were in sharp contrast. The prior pattern of association was maintained for most outcomes, but now the trend, with 12 months rather than 6 months elapsed time, was also significant for most outcomes.

Campaign Effects on Youth

The analysis focuses on four outcomes for youth: intentions to avoid initiating marijuana use and three indices: attitudes and beliefs about marijuana use, perceptions of social norms about marijuana use, and self-efficacy to avoid marijuana use if it is available. The intentions outcome focuses on the proportion of youth who said “definitely not” when asked about the likelihood of their using marijuana in the next year. The attitude and belief index includes questions about eight specific consequences of marijuana use for the respondent as well as general attitudes towards marijuana use; the perception of social norms index includes questions about what parents and friends would expect the respondent to do about marijuana use, while the self-efficacy index assesses the respondents confidence that he or she could refuse marijuana in a variety of circumstances. Each of the three indices are substantially related to intentions to use marijuana, which is closely related to prior marijuana use.

Table ES-6 presents a summary of all of the data for 12- to 18-year-olds, broken down between 12- to 13-year-olds and 14- to 18-year-olds. The table finds no significant trends. It finds only one significant association, which is negative. Youth who report more exposure on the general exposure measure report less strong rejection of marijuana use in the next year. However, that result is not repeated for the specific exposure index, and it is not repeated for the 14- to 18-year-olds nor when all of the youth are combined. In the absence of any trend data or replication with the other measures or populations, the result is appropriately seen as anomalous rather than as a basis for a negative inference about the Campaign effects.

Table ES-6. Evidence about Youth Campaign Effects
- 12- to 13-year-olds 14- to 18-year-olds
- Change Associated with exposure? Change Associated with exposure?
Outcome measure W1 W3 Specific exp. General exp. W1 W3 Specific exp. General
exp.
Percent definitely not intending to try marijuana 92% 90% No Yes 83% 83% No No
Attitude Belief Index 122 117 No No 88 93 No No
Social Norms Index 132 131 No No 83 89 No No
Self-Efficacy Index 100 95 No No 100 104 No No

† A monotonic dose-response relationship is where increasing the dose never reverses the direction of the effect. In this case, it means that higher recall of anti-drug advertising never was associated with a reversal of the effect of exposure on outcomes.

This arrow shows that the monotonic dose-response relationship was decreasing. Youth with more exposure were less likely to report that they would definitely not use marijuana in the next year.


These trend analyses were repeated for important subgroups defined by gender, sensation seeking (a personality characteristic defined by an interest in engaging in novel, intense and risky experiences, including illegal drug use), race/ethnicity, and urbanicity. Ten subgroups were analyzed for each of the four outcome measures, for Wave 1 to Wave 3 trends, and for association between the specific and general exposure measures and the outcomes. That meant a total of 120 analyses were examined. Of those, five trend or association analyses were significant at the p<0.05 level, about the same number as one would expect by chance. Of the five, three were consistent with a positive Campaign effect and two were consistent with a negative Campaign effect. The conclusion was that there is no reliable evidence of Campaign effects among subgroups.

Neither the overall results nor the subgroup analyses show consistent evidence supportive of a direct Campaign effect. However, this does not preclude the possibility of there having been an undetected effect due to one of the following explanations:

  • The samples for most analyses are substantial and were designed to be sensitive to changes of a specific size both for the overall sample and for important subgroups. Whatever the sensitivity, however, it is always possible that the Campaign achieved effects that were smaller than could be detected reliably by the available samples. This possibility is magnified for subgroup analyses that may depend on only a portion of the entire sample.

  • The effects of the Campaign may take longer to appear than the time that has passed since the start of Phase III. Youth have already been exposed to many anti-drug messages through other sources. The incremental effect of the Campaign-associated exposure may not be enough to achieve short-term effects, although it may have longer term cumulative effects.

  • The effects of the Campaign may not be felt solely through the influence of individual exposure to ads affecting those individuals’ beliefs and behavior. Rather, the effects may occur through a combination of direct and indirect exposure. The indirect exposure occurs when others in the youth’s social network are exposed and diffuse what they hear and see to the youth; it occurs when parents see the ads and are influenced in their interactions with their children; and it occurs when other adults in the community see the ads and other anti-drug promotion information, and are encouraged to support anti-drug public policies and anti-drug actions of community institutions. None of these indirect routes are fully tested in this volume. The included analyses are aimed at capturing direct effects only. The analyses in this volume compare individuals with more or less personal exposure. There is some preliminary evidence that parent exposure affects parent outcomes, and that some of those outcomes are related to youth behavior. However, that analysis does not establish the relation between parent exposure and youth outcomes. This will be examined in future reports.

In summary, thus far there is relatively little evidence for direct effects of the Campaign on youth. While there are scattered significant positive results, they are balanced by scattered significant negative results. Beginning with the Wave 4 semiannual report, there will be followup interviews available with youth measured at Wave 1, and at Wave 5 there will be followup for the samples from Wave 2 and Wave 3. Also, the evaluation will cover a longer period of Phase III of the Campaign. Both of these will make it possible to look for evidence of effects in additional ways, including comparing the rates of changes in outcomes for those with lower and higher early exposure and examining possible indirect effects. They may open the possibility of a modification of these conclusions.

Campaign Effects on Parents

The parent data provide a different and positive result. There were five outcome indices that were the focus of analysis in the report: (1) parent reports of talking with their children about drugs; (2) an index of belief and attitude items concerning talk (talk cognitions); (3) parent reports of monitoring their children; (4) an index of beliefs and attitudes concerning monitoring (monitoring cognitions); and (5) parent reports of engaging in fun activities with their children in and outside of the home.

There is evidence for positive trends between Waves 1 and 3 for four out of five of these indices. Either there was a statistically significant Wave 1 to Wave 3 positive trend overall, or among one or more important subgroups. The only exception was for the fun activities index, which showed no detectable change overall or for any subgroup. Table ES-7 summarizes the statistically significant results. In the case of monitoring behavior, there was an overall significant trend, so none of the trend data for subgroups are displayed. In the case of monitoring cognitions and talk behavior and cognitions, the overall trend was positive but not statistically significant, so several subgroups with significant trends are presented. There was clearly substantial evidence for positive trends between Waves 1 and 3.

In addition, there was strong evidence of association between the exposure measures and the outcomes: for the entire population, both the general and specific exposure measures were associated with level of talking behavior and cognitions, and fun activities. Monitoring cognitions was associated with general exposure for everyone, although the specific exposure measure was only significantly associated for fathers. Fathers were also the only subgroup to show a significant association of exposure (in this case specific exposure) and monitoring behavior

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