Research Findings - Prevention Research
Evaluation of the National Youth Anti-Drug Media Campaign: 2003 Report of Findings
The National Youth Anti-Drug Media Campaign (NYAMC) was funded by the Congress to reduce and prevent drug use among young people both directly, by addressing youth and indirectly, by encouraging their parents and other adults to take actions known to affect youth drug use. The major intervention components include television, radio, and other advertising, complemented by public relations efforts including community outreach and institutional partnerships. The goals of the evaluation are to determine: 1) if there is change in the behaviors, attitudes and beliefs targeted by the Campaign and 2) determine if such change can be attributed to the Campaign. The findings summarized below are from the fifth Evaluation report; the first three waves of data collection involved enrolling nationally representative samples of about 8,100 youth from 9 to 18 and 5,600 of their parents. The 2003 report includes the second (of three) follow-up interviews of the initial samples. The new report covers the period from September 1999 through June 2003. For the youth component of the Campaign, the Report focuses on evidence concerning the possible effects of the Marijuana Initiative that began in late fall 2002 and refocused the Campaign to emphasize marijuana use among youth. The report examines 1) exposure of youth and their parents to anti-drug messages (general exposure and specific exposure to ads run in the 2 months prior to the interview that are played on a computer to respondents); 2) effects on parents in terms of beliefs and behaviors associated with talking about drugs, and beliefs and behaviors regarding monitoring their child, and doing fun activities with their child; and 3) effects on youth cognitions, intentions, and initiation of marijuana use.
- Recall of Campaign Messages:
As in the 5th Report, most parents and youth recalled exposure to Campaign anti-drug messages. About 70 percent of parents and nearly 80 percent of youth report exposure to one or more messages through all media channels every week. Recall of TV advertising has climbed across the 3.5 years of the Campaign. In 2000, 24 percent of parents and 37 percent of youth recalled weekly exposure to specific TV ads; in 2002, before the Marijuana Initiative, recall among parents reached 51 percent and among youth reached 52 percent; in 2003, after the launch of the Marijuana Initiative recall rates had moved to 58 percent and 76 percent respectively. Both parents and youth also reported substantial recognition of the Campaign's "anti-drug" brand phrases. The 2003 youth component of the Campaign focused on strong marijuana Negative Consequences ads; they were evaluated positively by youth at a level comparable to most of the previous ads.
- Effects on Parents:
There continues to be evidence suggesting a favorable Campaign effect on parents. Overall, there are favorable changes on 4 of 5 parent belief and behavior outcome measures including talking about drugs with their children, doing fun activities with children and beliefs about monitoring of children. Evidence for Campaign effects on parents' monitoring behavior was much weaker. Lack of influence on monitoring behavior is a concern because it has been the focus of the parent Campaign for the past several years and is the parent behavior most strongly associated with youth nonuse of marijuana. In addition, there is no evidence for favorable indirect effects on youth behavior or beliefs as the result of parent exposure to the Campaign.
- Effects on Youth:
There is little evidence of direct favorable Campaign effects on youth, either for the Marijuana Initiative period or for the Campaign as a whole. The trend data in marijuana use is not favorable and for the (new) primary target audience, 14- to 16-year olds, past year use increased from 2000 through 2003, although the increase was already in place prior to the start of the Marijuana Initiative. However, an independent source of trend information, the Monitoring the Future Study, showed a decline in use for some age groups. In any case, youth who were more exposed to Campaign messages are no more likely to hold favorable beliefs or intentions about marijuana than are youth less exposed to those messages, both during the Marijuana Initiative period and over the entire course of the Campaign.
Because the Marijuana Initiative began just before the final wave of data collection, it is not possible to supplement the same-time comparisons of exposure and outcomes with delayed-effects comparisons of Marijuana Initiative exposure with later outcomes. These delayed-effects analyses will be examined in the final report planned for December, 2004.
Effects of the Early Risers Program on Young Aggressive Children's Peer Relations
Peer nominations for behavioral reputation, likeability, and friendship were examined after 4 years of an ongoing randomized, controlled prevention trial designed to interrupt the developmental trajectory of young aggressive children by improving peer relations. Participants included 125 moderately to highly aggressive children (program and control) and 1,489 of their 4th-grade classmates. Results indicated that program children (compared to controls) obtained higher reputation scores on leadership and social etiquette and chose friends with lower aggression. Self-reported quality of friendship also differed between groups, with program children reporting more companionship and recreation, program girls reporting more validation and caring, and severely aggressive program children reporting less aggression toward others than their control counterparts. These findings provide evidence for the generalization of program effects to a natural peer setting. Four Years of the Early Risers Early-Age-Targeted Preventive Intervention: Effects on Aggressive Children's Peer Relations. August, G.J., Egan, E.A., Realmuto, G.M., and Hektner, J.M. Behavior Therapy, 34(4), pp. 453-470, 2003.
The Early Risers Effectiveness Study
This study evaluated the effectiveness of the Early Risers "Skills for Success" Program when implemented by neighborhood family resource centers available to urban children and their families. Kindergarten and first-grade children (n=327) enrolled in 10 schools were screened for aggressive behavior, and randomized to two model variations of the Early Risers Program or a no-intervention control condition. The full-strength model (CORE + FLEX) included child and parent/family components; the partial model (CORE-only) offered only the child component. The intervention was delivered over two continuous years. CORE + FLEX children showed higher levels of program attendance than their CORE-only counterparts but no differences on outcomes measures were observed between models. When both program models were collapsed and compared to controls, program children showed significant gains on measures of school adjustment and social competence, the most aggressive program children showed reductions in disruptive behavior, and program parents reported reduced levels of stress. August, G.J., Lee, S.S., Bloomquist, L., Realmuto, G.M., and Hektner, J.M. Dissemination of an Evidence-Based Prevention Innovation for Aggressive Children Living in Culturally Diverse, Urban Neighborhoods: The Early Risers Effectiveness Study. Prevention Science, 4(4), pp. 271-286, 2003.
Effectiveness of the Coping Power Program and of Classroom Intervention with Aggressive Children at One-Year Follow-Up
This study examines key substance use, delinquency, and school-based aggressive behavior outcomes at a 1-year follow-up for a cognitive-behavioral intervention delivered to aggressive children and their parents at the time of these children's transition to middle school. This effectiveness study explored whether a classroom intervention directed at teachers and at all of the parents in the intervention classrooms enhanced the effects of the Coping Power program with at-risk children. The at-risk sample of boys and girls was identified through 4th-grade teacher ratings, and intervention took place during the 5th- and 6th-grade years. The Coping Power child component included school-based groups focusing on anger management and social problem solving skills, and the Coping Power parent component addressed parenting and stress-management skills. The current results indicate that prior findings of post-intervention improvement for this sample (Lochman & Wells, 2002b) has led to preventive effects on delinquency and on substance use for older and moderate-risk children. The Coping Power program, in conjunction with a classroom-level intervention, also reduced school aggression one year after the intervention was completed. In addition, it appears that the classroom intervention facilitates radiating effects on reduced substance use for other at-risk children in the same classrooms who did not receive Coping Power. Lochman, J.E. and Wells, K.C., Effectiveness of the Coping Power Program and of Classroom Intervention with Aggressive Children at One-Year Follow-Up. Behavior Therapy, 34(4), pp. 493-515, 2003.
Reasons for Teachers' Adaptation of Prevention Curricula for Non-White Students
There is increasing evidence to suggest that the adaptation of classroom-based prevention curricula in the nation's middle schools is widespread. This study investigated the reasons for teachers' adaptation of prevention curricula. A randomly selected sample of nationally representative lead middle school substance abuse prevention teachers from 50 states and the District of Columbia answered questions concerning eight student problems or needs (i.e., poverty; violence; gang activity; discipline problems; sexual activity; various racial/cultural groups; special needs/disabilities; student and parent substance use) that were hypothesized to constitute reasons for curriculum adaptation. Controlling for a variety of school and teacher characteristics, teachers in high minority schools were more likely to adapt curricula in response to three of the eight characteristics presented (i.e., youth violence; limited English proficiency; and various racial/ethnic or cultural groups within classroom). It is suggested that curriculum developers make a systematic effort to understand how teachers are adapting their curricula in high minority schools and incorporate these modifications, if found effective, into their curricula. Ringwalt, C.L., Vincus, A., Ennett, S., Johnson, R., and Rohrbach, L.A. Reasons for Teachers' Adaptation of Substance Use Prevention Curricula in Schools With Non-While Student Populations. Prevention Science, 5(1), pp. 61-67, 2004.
An Acute Post-Rape Intervention to Prevent Substance Use and Abuse
Rape trauma frequently is associated with extreme acute distress increasing the risk of developing psychopathology and substance use or abuse post-rape, with the degree of internal distress positively predicting future problems. The nature of post-rape forensic evidence collection procedures may exacerbate initial distress, thus potentiating post-rape negative emotional sequelae. Substance use may increase in an effort to reduce this distress. To address this outcome, a two-part video intervention was develop for use in acute post-rape time frames with two goals: to minimize anxiety during forensic rape examinations, thereby reducing risk of future emotional problems; and to prevent increased post-rape substance use and abuse. Pilot data with 124 rape victims who completed a police report and were brought for medical care immediately following such a report and who completed a 6-week post-rape assessment are included in this article. Half the women saw a 17-minute video immediately prior to the forensic examination. The data indicated that the low-cost, easily administered intervention was effective in reducing risk of marijuana abuse at six weeks. Trends also were noted in favor of the intervention in the subgroup of women who were actively using substances pre-rape (among pre-rape alcohol users, 28% of viewers versus 43% nonviewers met criteria for post-rape alcohol abuse; among pre-rape marijuana users, the rates of post-marijuana use were 17% and 43% respectively). While still preliminary, these data support the use of immediate, brief intervention via the video to target substance abuse within a vulnerable population. Acierno, R., Resnick, H.S., Flood, A. and Holmes, M. An Acute Post-Rape Intervention to Prevent Substance Use and Abuse. Addictive Behaviors, 28, pp. 1701-1715, 2003.
Drug Abuse Prevention Program Development - Results Among Latino and Non-Latino White Adolescents
Five program development studies from Project Towards No Drug Abuse (TND) were reanalyzed to discern Latino versus non-Latino Whites similarities and differences in receptivity to a wide variety of high school-based drug abuse prevention activities. In most of the program development studies, these youth attended alternative (continuation) high schools in Southern California. Although there were a total of 46% Latino students in these schools, 99% of the students indicated English as the main language spoken at school and home. Thus, taken together, almost all Latino youth in the various studies analyzed preferred to respond to survey questions in English. Latinos were relatively low in socioeconomic status (SES) and used drugs less frequently than non-Latino whites. Still, this group of highly acculturated Latinos and non-Latino Whites (37% of the school population) perceived that they were attending alternative schools for the same reasons (e.g., lack of credits, truancy). Very few differences in receptivity ratings of proposed TND activities were found as a function of ethnicity. In other words, the data suggest that the same types of lessons are applicable to older teens in both ethnic groups. Sussman, S., Yang, D.Y., Baezconde-Garbanati, L., and Dent, C.W. Drug Abuse Prevention Program Development - Results Among Latino and Non-Latino White Adolescents. Evaluation & The Health Professions, 26(4), pp. 355-379, 2003.
Preventing Early Onset Substance Use by Parental Monitoring
The Family Check-Up (FCU) is a brief family-centered intervention focused on family management practices. Within the context of a randomly assigned multilevel family intervention, high-risk youth and families (n = 71) were selected for videotaped home observation that includes a task to assess parent monitoring. Parents in the intervention group were offered annual feedback on the yearly assessment, including their home observation. Using an intention-to-treat design, analyses revealed intervention effects on early-adolescent substance use and observed parent monitoring by the first year of high school (Year 4 of follow-up). As in previous research, parents of high-risk adolescents were observed to decrease monitoring from Grades 7 to 9. However, families randomly assigned to the family intervention maintained their monitoring practices. Regression analyses revealed the prevention effect of the FCU on substance use was mediated by changes in parental monitoring. Dishion, T.J. Nelson, S.E. and Kavanagh, K. The Family Check-Up with High-Risk Young Adolescents: Preventing Early Onset Substance Use by Parent Monitoring. Behavior Therapy, 34, pp. 553-571, 2003.
Advocacy Activities to Address Environmental Influences Led to Less Smoking among Teenagers
Most smoking prevention and cessation interventions for adolescents show little sustained effects on smoking behavior. Since behavior change is embedded in the social context, the authors designed an intervention that involved adolescents in advocacy about social and environmental factors that influence smoking as a way to test an alternative approach. Ten continuation high schools were randomized to receive an advocacy curriculum where 11th and 12th grade students carried out activities to counter environmental influences on smoking in their communities (i.e., the treatment) or a curriculum where students learned about drug and alcohol abuse prevention (control). Compared with control schools, students in treatment schools showed significant net changes from baseline to the end of the semester (post intervention) for regular smoking, involvement in community-advocacy activities. The findings were significant for students who were regular smokers but not for those who were non-smokers or light smokers. Regular smoking decreased 3.8% in treatment schools and increased 1.5% in control schools. Regular smoking continued to decrease at 6-months post-intervention in treatment schools, with a total change in prevalence from 25% to 20%. Involvement in community-advocacy activities and three measures related to social cognitive theory --- perceived incentive value, perceived self-efficacy, and outcome expectancies also showed significant net changes between treatment and control schools that were maintained at 6-months post-intervention. Winkleby, M.A., Feighery, E.C., Dunn M., Ahn, D. and Killen J. Effects of an Advocacy Intervention to Reduce Smoking Among Teenagers. Archives of Pediatric Adolescent Medicine, 158, pp. 269-275, 2004.
Monetary Incentives Increase Community-Based Prevention Participation Rates
This investigation was designed to examine the influence of a research incentive ($100) and requirement (videotaping) on decisions to participate in prevention research. The participants were 685 parents of 6th graders from 36 rural Iowa schools who completed a telephone survey prospectively assessing factors relevant to their participation in a prevention intervention research project. The parents were later recruited for actual participation in the project. Individuals were significantly attracted by the incentive and marginally deterred by the requirement. Interaction analyses revealed that the positive incentive effect was stronger among prospective participants with less education and who were otherwise less likely to participate. These findings indicate that monetary incentives can be useful for increasing participation rates and may help reduce sampling bias by increasing rates most strongly among individuals who are typically less likely to take part in research projects. Guyll, M., Spoth, R., and Redmond, C. The Effects of Incentives and Research Requirements on Participation Rates for a Community-Based Preventive Intervention Research Study. The Journal of Primary Prevention, 24, pp. 25-41, 2003.
What Works in Media Strategies Targeting High Sensation Seekers
This review examines media strategies used in effective drug prevention campaigns targeting high sensation seekers. Both experimental lab and field studies have been used to establish and test SENTAR (i.e., sensation-seeking targeting) approaches to segment the audience. The SENTAR principles for designing campaigns include: use the sensation seeking trait as a key targeting variable; design prevention messages that are high in sensation value; use pre-campaign research with high sensation seeking members of the target audience; and place prevention messages in high-sensation value contexts. In earlier studies this targeting strategy has resulted in significant drops in 30-day marijuana use by adolescents. Having established that SENTAR works, new studies focused on the factors that were influencing the processing and persuasiveness of the ads including emotional responses; visual and sound effects, storyline and consequences of drug use portrayed in ads. The influence of these mediating factors was expected to differ in youth. High sensation seekers reported a much stronger negative reaction to the consequences of marijuana than low sensation seekers, but their emotional reactions were inconsequential in affecting attitudes whereas low sensation seekers' emotional reaction was the only factor affecting attitudes. Together these studies suggest that sensation seeking is a risk factor influencing drug use that can be addressed through ads that appeal to the sensation seeker's need for arousal and stimulation. Stephenson, M.T. Mass Media Strategies Targeting High Sensation Seekers: What Works and Why. Am J Health Behav 27 (Supplement 3), pp. S233-S238, 2003.
Sensation Seeking is a Moderator of Peer Effects and Perceived Peer Marijuana Use on Cigarette and Marijuana Use
This study tested the concurrent effects of peer influence and protective cognitive variables on marijuana and cigarette use to determine if they are contingent on adolescent sensation seeking. It tested two hypotheses: (1) low sensation-seekers would be more likely to resist pressures from risk-taking peers than their high-sensation-seeking counterparts and (2) low sensation seekers are more likely to be deterred from cigarette and marijuana use by the perceived negative consequences of harm than high sensation-seekers. Data are based on survey responses of 3127 eighth graders from 10 small towns and rural communities. Findings indicate that sensation seeking is a risk factor for drug use among high but not low sensation seekers; however, sensation seeking does not become a risk factor in the absence of social pressures to use substances. Aspirations inconsistent with marijuana use appeared protective for high sensation seekers. Since low sensation seekers appear to be at relatively low risk even in the presence of peer risk factors or the absence of cognitive factors, the primary audience for substance use prevention efforts should be the sensation-seeking young adolescents and should seek to channel this group into alternative arousing and risk taking activities with nonsubstance-using peers. Slater, M.D. Sensation-Seeking as a Moderator of the Effects of Peer Influences, Consistency with Personal Aspirations, and Perceived Harm on Marijuana and Cigarette Use among Younger Adolescents. Substance Use and Misuse 38, pp. 865-880, 2003.
Familism, Parental Monitoring & Knowledge as Predictors of Adolescent Drug Use
The authors investigated relationships between marijuana and inhalant use and measures of familism, parental monitoring, drug use knowledge and acculturation as well as demographic factors in 1,094 Anglo and Hispanic youth from 5 school districts in southwest Arizona. Outcome measures addressed lifetime and 30-day marijuana and inhalant use. Hispanics exhibited higher use across all measures. Among Hispanic youth, high acculturation was associated with low marijuana but high inhalant use. In both Hispanics and Anglos positive family relations and parental monitoring were strongly associated with reduced marijuana use but only among youth most knowledgeable about drugs. Familism and monitoring were not associated with diminished use among the less knowledgeable. For inhalants, monitoring combined with high knowledge or with high familism was associated with attenuated use. The role of knowledge in reducing drug use suggests continuing to disseminate factual material. Prevention strategies also should incorporate a family component to inform parents and open lines of communication. Ramirez, J.R., Crano, W.D., Quist, R. Burgoon, M., Alvaro, E.M. and Grandpre, J. Acculturation, Familism, Parental Monitoring, and Knowledge as Predictors of Marijuana and Inhalant Use in Adolescents. Psychology of Addictive Behaviors. 18(1), pp. 3-11, March 2004.
Comparing African American and Caucasian Marijuana Use from Early Adolescence Through Young Adulthood
Although epidemiological studies have consistently reported that African American adolescents are less likely to use drugs than their Caucasian counterparts, few researchers have examined the developmental trajectories of drug use to identify whether and when differences in marijuana use appear and the nature of these differences. This study compared marijuana use patterns for African American and Caucasian youth across 7 waves of data using a community based dataset collected as part of the evaluation of Project DARE. Because the DARE intervention was found to have no effects on any program targets, this dataset provides an appropriate community sample for investigating developmental changes in drug use over time. 1,354 students (49.7% male, 77.4% Caucasian) were interviewed once a year in the sixth through tenth grades and again at age 20. Consistent with prior research, early onset of substance use was associated with low church involvement, low peer pressure resistance, high sensation seeking, and high positive and low negative expectancies about the effects of marijuana. These relationships held true for both African American and Caucasian adolescents. Relationships between marijuana use patterns and other outcomes including psychological problems, aggression and arrests were also examined. Among Caucasian adolescents, those with the earliest onsets reported more negative outcomes, whereas adolescents with the latest onsets reported fewer. However, the pattern was different for African American adolescents. The early-onset and late-onset African American groups were similar on outcome variables and, by age 20, these groups were using marijuana at rates that were low and indistinguishable from each other. By contrast, African American adolescents who began using marijuana around the ninth grade were significantly higher on these outcomes than were any of the other groups. Thus, initiation of marijuana use in mid-adolescence among African Americans poses the greatest risk for continued use. Brown, T.L., Flory, K., Lynam, D.R., Leukefeld, C., and Clayton, R.R. Comparing the Developmental Trajectories of Marijuana Use of African American and Caucasian Adolescents: Patterns, Antecedents, and Consequences. Experimental and Clinical Psychopharmacology, 12, pp. 47-56, 2004.
Maternal Influences on Urban Adolescent Girls' Smoking Intentions
Prior research has shown that parents who smoke are more likely to have children who smoke. Moreover, adolescents have been found to overestimate the number of adults and teenagers who smoke. This overestimation produces an expectation of smoking as normative and has been associated with an increase use of cigarettes among adolescents. This study examined maternal social influences on cigarette usage among urban minority girls with interview data from 450 mother-daughter dyads recruited from 30 New York City public and parochial middle schools. Girls in this sample ranged in age from 11 to 15 years and reported smoking rates of about 18% and smoking intention rates of 24%. Most of the sample was either Black or Latina, with smaller percentages of other groups (White, Native American, Asian). Neither mothers' reports of their own smoking nor maternal attitudes toward children's smoking were predictive of girls' experimental smoking and intentions to smoke in the next year. However, girls who perceived their mothers to be smokers were more likely to have tried smoking and to say that they intend to try smoking compared to girls who perceived their mothers to be nonsmokers. Compared to girls with low normative expectations of adult smoking, girls with high normative expectations were 2.89 times more likely to have tried cigarettes and 2.32 times more likely to intend to smoke. These findings suggest that preventive interventions aimed at correcting normative expectations of smoking among parents and youth may be helpful in deterring smoking among children. Nichols, T.R., Graber, J.A., Brooks-Gunn, J., and Botvin, G.J. Maternal Influences on Smoking Initiation Among Urban Adolescent Girls. Journal of Research on Adolescence, 14, pp. 73-97, 2004.
Ethnicity and Training Affects Observer Ratings of Family Interactions
Observer ratings are frequently used alone or in combination with other methods to provide more accuracy in measurement of health related behaviors. The present study illustrates the use of generalizability theory (Cronbach, Gleser, Nanda, & Rajarantnam, 1972) to assess possible sources of bias in observer ratings, as this approach allows for simultaneous examination of the contributions of multiple sources of error in the variance of observer ratings. In this study, two factors that may affect the level of rater agreement are examined: coder race and the interaction between coder race and observed family member (i.e., "target") race. Thirty behavioral scales were rated on three occasions during an initial 5-week training period. African-American and European-American coders observed videotaped interactions occurring in one African-American and one European-American parent-child dyad. For each scale, levels of rater bias and rater agreement were examined over time. Although most scales showed decreasing levels of bias with training, some did not. For scales showing a main effect for coder race, European-American coders rated targets more favorably than African-American coders. For scales susceptible to coder race by target race interactions, coders tended to favor other-race rather than same-race targets. Melby, J.N., Hoyt, W.T., and Bryant, C.M. A Generalizability Approach to Assessing the Effects of Ethnicity and Training on Observer Ratings of Family Interactions. Journal of Social and Personal Relationships, 20(2), pp. 171-191, 2003.
Brief Measures of Sensation Seeking for Screening and Large-Scale Surveys
Sensation seeking is central to research on the prevention of risky health behaviors, but most measures of sensation seeking are fairly long. To increase the chances of inclusion of sensation seeking in research projects, the authors developed and evaluated two brief indices of sensation seeking, a four-item measure that retains the framework of the Sensation Seeking Scale-Form V (which is an 8-item measure), and a two-item measure focused on the risk-taking elements of sensation seeking. The performance of these new indices was compared with that of two well-documented longer measures of sensation seeking, based on data provided by more than 5,000 youth in grades seven through eleven. Psychometric analyses indicated that the internal consistency of the two new measures was very good overall and across grade and sex categories. Additionally, the new indices correlated with a series of risk and protective factors as well as tobacco, alcohol, and marijuana use. Since both indices performed in ways remarkably similar to the established measures of sensation seeking, they should prove useful for future research involving risky health behaviors. Stephenson, M.T., Hoyle, R.H., Palmgreen, P., Slater, M.D. Brief Measures of Sensation Seeking for Screening and Large-Scale Surveys Drug and Alcohol Dependence, 72, pp. 279-286, 2003.
Anger, Aggression, Risky Behavior, and Crash-Related Outcomes
This research sought to map the characteristics of high anger drivers who perceive they have a problem with driving anger (HAP drivers) and high anger drivers who perceive they have no problem with driving anger (HAPN drivers). Participants were 153 introductory psychology students (median age=19). Participants completed self-report measures of driving anger and a driving survey to characterize driving style in addition to other psychological measures. In addition, participants recorded driving miles, driving anger, and aggressive and risky driving in a log. There was some evidence that HAP drivers were somewhat angrier than HANP drivers. However high anger drivers did not differ from one another in terms of their anger during rush hour traffic, in their personally most angering situations, or on the frequency and intensity of anger in day-to-day driving. Analyses support the construct validity of the Driving Anger Scale. Deffenbacher, J.L., Lynch, R.S., Filetti, L.B., Dahlen, E.R., and Oetting, E.R. Anger, Aggression, Risky Behavior, and Crash-Related Outcomes in Three Groups of Drivers. Behaviour Research and Therapy, 41, pp. 333-349, 2003.