OBJECTIVE. The purpose of this work was to determine whether a pediatric practice-based smoking prevention and cessation intervention increases abstinence rates among adolescents.
METHODS. Eight pediatric primary care clinics were randomly assigned to either intervention or usual care control condition. The provider- and peer-delivered intervention tested was based on the 5A model recommended by the US Public Health Service clinical practice guidelines and the American Academy of Pediatrics and consisted of brief counseling by the pediatric provider followed by 1 visit and 4 telephone calls by older peer counselors aged 21 to 25 years. A consecutive sample of patients aged 13 to 17 years scheduled for an office visit was eligible regardless of smoking status. Of 2711 patients who agreed to participate, 2709 completed baseline assessments, and 2700 (99.6%) and 2690 (99.2%) completed 6- and 12-month assessments, respectively.
RESULTS. Compared with the usual care condition, nonsmokers who received the provider- and peer-delivered intervention were significantly more likely to self-report having remained abstinent at 6-month and 12-month follow-up; smokers who received the provider- and peer-delivered intervention were more likely to report having quit at the 6-month but not the 12-month follow-up. A number of adolescent characteristics (eg, age, peer smoking, tobacco dependence, and susceptibility) were found to be predictive of abstinence at follow-up.
CONCLUSIONS. A pediatric practice-based intervention delivered by pediatric providers and older peer counselors proved feasible and effective in discouraging the initiation of smoking among nonsmoking adolescents for 1 year and in increasing abstinence rates among smokers for 6 months.
Few adolescent daily smokers believe that they will still be smoking in 5 years; however, 75% are indeed still smoking 5 years later.1 Adolescent smokers are interested in quitting: nearly have seriously thought about it, and 64% have tried.1 Among 17-year-old smokers, 40% are interested in cessation treatment.1 A recent review of adolescent cessation trials concluded that there are no proven programs to help teens stop smoking but suggested interventions based on cognitive behavioral therapy and sensitive to stages of change seem promising.2 The American Academy of Pediatrics suggests that pediatricians are well positioned to take an active role in addressing this issue.3–5 Because of their credibility and long-term relationships with patients, pediatric clinicians have many opportunities to intervene with adolescent smokers, as well as with nonsmokers to prevent initiation.6,7 Between 63% and 85% of adolescents are seen for preventive care each year.8–10 In a recent study, 63% of adolescents were seen in primary care over the course of a year, 83% over 2 years.11
There is strong evidence that brief counseling by health care providers encourages cessation in adults.12 In the absence of data regarding the efficacy of clinical interventions with adolescents, existing guidelines recommend delivering strong messages encouraging abstinence.3,12–15 Nevertheless, many pediatricians do not routinely address tobacco use16–24 and are more likely to discourage initiation than encourage cessation.16 Although peer counseling has successfully modified the risks of HIV infection25 and teen pregnancy26,27 in adolescents, this approach has not been used with tobacco.
Here we present the results of a randomized, controlled trial evaluating the efficacy of a practice-based smoking prevention and cessation intervention for adolescents delivered by pediatric providers and older peer counselors. It was hypothesized that the intervention would increase abstinence rates for both baseline smokers and nonsmokers.
All 11 of the central Massachusetts clinics with ≥3 pediatricians were invited to participate; 8 agreed. The 8 practices were stratified by size and randomly assigned to either the provider- and peer-delivered intervention (PPDI) or usual care (UC). Allocation to condition was concealed until interventions were assigned. An office management system was established to support the delivery of the PPDI. At baseline and 12 months, providers (pediatricians, nurse practitioners, physician's assistants, and pediatric residents) at all of the sites completed a survey concerning demographic data, as well as practice behaviors, knowledge, attitudes, and self-efficacy with regard to smoking prevention and cessation with adolescents.28 Providers at the PPDI sites were then trained to deliver the intervention; UC providers received no training and no materials to provide patients. All of the patients aged 13 to 17 years scheduled for routine or acute care office visits were eligible to participate regardless of smoking status. Subjects were recruited through letters on the physician's letterhead, telephone calls, and postings in the clinics. A research assistant met with interested patients at the clinic. Parental consent and youth assent were obtained as approved by the University of Massachusetts Medical School Institutional Review Board. Participants were offered a gift certificate at each of the 3 assessment points, $10 at baseline and $25 at 6 months and 1 year of follow-up. Because random assignment occurred at the level of the practice, participants were blinded to group assignments, and providers were only aware of their group assignment. The study, including patient recruitment and follow-up, was conducted between 2000 and 2004.
The provider-delivered component of the PPDI was based on the 5A model recommended by the US Public Health Service clinical practice guideline and the American Academy of Pediatrics,3,12 adapted for use with adolescents in the language used. The intervention incorporated a patient-centered approach in which the providers ask about smoking, advise cessation or continued abstinence, and refer the patient to the peer counselor to develop a personalized strategy for cessation or maintained abstinence (see Fig 1 for the provider algorithm). A 1-hour group session trained providers about adolescent smoking, nicotine addiction, health risks, benefits of quitting, and the provider's role. Clinical practice guidelines3,12 were presented, and the peer counselor intervention was introduced. The providers practiced the intervention algorithm in pairs. Two to 4 weeks later, providers met individually with the project director for practice and feedback to ensure fidelity to the algorithm. At the PPDI sites, the algorithm was attached to the patient's medical chart.
Peer Counselor Intervention
Peer counselors were female college students aged 21 to 25 years who had smoked as adolescents and successfully quit. They were selected via interview and reference checks for their communication skills, nonjudgmental attitude toward smokers, and for reporting quitting without pharmacologic aids and with difficulty, providing a coping model for smoking cessation for adolescent patients in the intervention condition. Peer counseling combined the 5A model with motivational interviewing and behavior change counseling. Peer counselors were assigned to 1 or 2 clinics, met with participants in those clinics for an initial 15- to 30-minute session immediately after the provider, and followed up with 10-minute telephone calls after 2, 6, 12, and 21 weeks. They were paid by the hour. The content of the peer counseling was tailored to the patient's smoking status and adapted to adolescents by incorporating triggers, strategies, and barriers to quitting relevant to adolescents based on the literature and focus group testing conducted in the development phase of the study and by including a discussion of tobacco advertising, promotion, and social norms found to be important to adolescent smoking29,30 (see Table 1).
Peer counselors were trained over 5 days in the study protocol and in motivational interviewing counseling skills (eg, respect, collaboration, choice, empowerment, rapport building, reflective listening, effective questioning, and summarizing) and were required to demonstrate competency. During the study, quality control was assured by monitoring interviews and providing feedback. To evaluate the degree to which the providers and peer counselors faithfully executed their intervention algorithms, patients were asked to complete a patient exit interview within 48 hours of their visit either in person or by telephone.31
Patients completed surveys at baseline and at 6- and 12-month follow-up. Before completing the baseline assessment, patients were shown a carbon monoxide monitor and were informed that it might be used to confirm their self-reported smoking status. The follow-up surveys reminded patients that they might be tested. Patients who reported having never smoked or having smoked 1 or 2 puffs but not in the past year were classified as nonsmokers. Those who reported smoking occasionally or regularly were classified as current smokers, whereas those who had smoked in the past year but not in the past 30 days were classified as former smokers.32,33 Patients were asked about either their confidence in their ability to stop smoking (smokers) or to remain smoke-free (nonsmokers and former smokers) on an 11-point scale. Depressive symptoms were assessed with the Children's Depression Inventory (CDI)-Short Form self-report measure.34 Patients were asked if they had ever been told that they had attention deficit disorder (ADD) or attention deficit hyperactivity disorder (ADHD). Additional items assessed smoking in the home and peer smoking.35 For smokers, stage of change (adapted from Di Clemente36), past 30-day cigarette consumption,37 and number of days smoked were assessed.38 The modified Fagerström Tolerance Questionnaire (mFTQ)39 assessed level of nicotine dependence, and the Hooked on Nicotine Checklist (HONC) measured loss of autonomy over tobacco use.40,41 Nonsmokers and former smokers were asked about their susceptibility to future smoking.42 The 6-month survey for PPDI participants included an assessment of the helpfulness of the peer counselor telephone follow-ups.
Sample size was determined using the method suggested by Donner et al43 for studies with randomization by cluster. Using this procedure we determined the need for a sample of 300 subjects per pediatric clinic and 4 pediatric clinics per condition to achieve the estimated effect size with 80% power at the 5% significance level. The UC and PPDI cohorts were compared at baseline using the χ2 and Fisher's exact tests for categorical data, t tests for normally distributed continuous or ordinal data, and Mann-Whitney U tests for data that were not normally distributed. Predictors of smoking status at the 6- and 12-month follow-ups were identified using backward stepwise logistic regression analyses, adjusting for clustering by site. The results were compared with forward stepwise logistic regression analyses, adjusting for clustering by sites, and the outcomes were the same. Gender was forced into all of the models. A carry-forward approach assigned baseline values for missing values at 6 months and values from the 6-month assessment for missing values at 12 months. Independent variables included treatment group (PPDI or UC), age, ethnicity, baseline smoking status, confidence to quit or remain a nonsmoker, and history of ADD/ADHD, plus follow-up values for CDI, peer smoking, school performance, knowledge score, household smoking, and number of office visits between baseline and 6-month follow-up. All of the variables were entered to create a preliminary model, where interaction terms were added: intervention by baseline smoking status, intervention by gender, and baseline abstinence status by gender. Additional separate models were run for baseline smokers and nonsmokers. The models for smokers included HONC scores at follow-up and stage-of-change scores from the previous assessment period (baseline at 6 months or 6 months at 12 months). Baseline susceptibility scores were included in the model for nonsmokers.
A total of 2711 patients 13 to 17 years of age were recruited from 4721 patients approached (recruitment rate of 57%), ∼90% from well visits and 10% from acute care visits. Baseline data were available from 2709, 1365 in UC and 1344 in PPDI (Table 2). Of the total, 9.7% (n = 262) were smokers, 10.6% (n = 145) in UC and 8.7% (n = 117) in PPDI (P > .05). The PPDI group had more females (P = .005), Hispanics (P = .03), and patients with ADD/ADHD (P = .009). Retention rates were 99.6% at 6 months and 99.2% at 12 months. Smokers were less likely than nonsmokers to complete the final assessment. The progress of patients throughout the trial is presented in the consort flow diagram (Fig 2).
Providers in the UC and PPDI conditions did not differ with respect to any baseline characteristics. Providers averaged 42 years of age and expressed greater confidence in preventing initiation than in aiding cessation. Forty eight were pediatricians, 10 were nurse practitioners, 2 were pediatric residents, 1 was a physician's assistant, and 3 were unknown.
Fidelity to Intervention
Exit interview data were available for 2707 patients (99.8%). According to the patient exit interviews, PPDI providers presented 84% of the protocol content to smokers and 72% to nonsmokers and former smokers. An analysis of the exit interview data are presented elsewhere.31 Compared with UC patients, PPDI patients felt that their provider had a good understanding of their feelings about smoking (66% vs 49%; X42 = 77.55; P < .0001), felt it was the provider's job to discuss smoking with teens, (80% vs 74%; X942 = 15.47; P = .004), and spent more time doing so (4.3 minutes vs 2.9 minutes; z for Mann-Whitney U = −13.66; P < .0001).
For most of the protocol steps, patients reported that peer counselors completed them ≥98% of the time. Intervention steps completed <90% of the time were sharing the prevalence of teen smoking with current smokers (88%), and, with former smokers, reviewing the most recent quit experience (86%) and asking what the patient likes about smoking (82%). Peer counselors delivered more of the required steps to smokers (96.3%; mean: 19.3 of 20.0; SD: 1.19) and former smokers (96.3%; mean: 14.4 of 15.0; SD: 2.59) compared with nonsmokers (92.3%; mean: 12.0; SD: 0.82; F2,1216 = 1767.44; P < .005).
Compared with UC, PPDI nonsmokers had a twofold increase in the odds of remaining abstinent at 6-month follow-up (odds ratio [OR]: 2.15; SE: 0.72; z = 2.29; 95% confidence interval [CI]: 1.12–4.15) and a 1.5-fold increase at 12-month follow-up (OR: 1.64; SE: 0.41; z = 2.01; 95% CI: 1.01–2.67; Fig 3A). Abstinence at 6 months was predicted by being in the PPDI condition and baseline confidence to refrain from smoking, whereas the number of friends who smoked at 6 months and susceptibility to smoking at baseline decreased the likelihood of being abstinent (n = 2355; Wald X52 = 96.26; P < .0005; Table 3). The PPDI and baseline confidence to refrain from smoking increased the likelihood of being abstinent at 12 months, whereas baseline susceptibility and having higher depression scores and more friends who smoke at 12 months decreased the odds of abstinence (n = 2357; Wald X62 = 162.65; P ≤ .0005; Table 4).
Compared with UC, PPDI smokers had a 1.5-fold increase in the odds of being abstinent at the 6-month follow-up (OR: 1.59; SE: 0.22; z = 2.23; 95% CI: 1.06–2.40; Fig 3B). The likelihood of abstinence at 6 months was increased by being in the PPDI condition and having had more visits to the doctor and decreased by older age, higher HONC scores, and more friends who smoke measured at 6 months (n = 229; Wald X62 = 67.90; P < .0005; Table 5).
Abstinence rates for smokers did not differ between conditions at the 12-month follow-up. The likelihood of being abstinent was increased by having had more visits to the doctor within the first 6 months postintervention and decreased by a higher HONC score at baseline (n = 229; Wald X32 = 42.14; P ≤ .0005; Table 6).
Patient Acceptance of Intervention
Patients overwhelmingly found the PPDI helpful (98.2%) and interesting (93.8%). They were comfortable discussing smoking with the peer counselor (96.4%), who they felt understood their feelings about smoking (98.5%). Patients increased their commitment to either remain or to become a nonsmoker (Wilcoxon signed-ranks test, z = −10.66; P < .0005). Smokers and nonsmokers did not differ in their receptivity to the intervention. Nonsmokers liked the printed materials used in the intervention more than smokers (X22 = 12.04; P ≤ .002); most (82.2%) read it, and 23.4% shared the booklet with friends.
Our findings indicate that a smoking prevention and cessation intervention can be feasibly delivered in pediatric practices and can improve abstinence rates for smokers for ≥6 months and prevent the initiation of smoking for ≥1 year. Although the differences detected between the intervention and control conditions were relatively small, they are encouraging considering the tremendous challenge of reducing smoking initiation and increasing cessation among adolescents. Differences in cessation among smokers at 6-month follow-up were both practically, as well as statistically, significant, lending support for clinical groups to consider implementing this intervention for their patients who smoke. It is not known whether extending the calls from the peer counselor beyond 6 months would have helped to extend the favorable impact on cessation. Such calls could focus on preventing relapse or facilitating a new cessation attempt by discussing what patients learned from their most recent quit attempt and would be practical, because peer counselors would conduct the calls with no additional burden to the pediatric practice. It also would be of interest to determine how long a 1-time intervention is effective in discouraging the initiation of smoking beyond the year of follow-up assessed in the present study and whether the effect noted could be enhanced. The differences between the groups in abstinence rates for nonsmokers, although statistically significant, were modest and decreased from 6- to 12-month follow-up, suggesting a possible decrement in effect over time. In addition, it would be important to determine whether an intervention delivered by either providers or peers alone would be effective, because from a practical perspective the provider-delivered counseling component used in this study could be easily implemented in pediatric practices.
Consistent with the literature, peer smoking predicted smoking initiation,44–46 but confidence in being able to refrain from smoking increased the likelihood that youth would remain abstinent. Our data add additional support to the predictive validity of Pierce's simple measure of susceptibility to smoking.42 Also consistent with the literature47–51 was our finding that greater depressive symptoms were associated with increased smoking initiation.
More frequent visits to the doctor increased the likelihood that smokers would have quit at both 6- and 12-month follow-ups. More frequent visits may have been because of illnesses related to smoking, serving to motivate smokers to quit. Alternatively, providers may have scheduled follow-up appointments to support patients in their efforts to quit, thereby improving the likelihood of success.
The data from this study support the predictive validity of the HONC as a measure of loss of autonomy.52 As HONC scores increased, the likelihood of abstinence at both the 6- and 12-month follow-up periods decreased. When the HONC was not included in the regression models, the mFTQ predicted cessation outcome at 6 months but not at 12 months. When the HONC and mFTQ were included together, the HONC predicted cessation at both end points, but the mFTQ was not a significant predictor of cessation at either end point.52 This suggests that the HONC should be used in preference to the mFTQ in cessation studies with adolescents.
Older smokers and those with more friends who smoked were less likely to be abstinent at 6-month follow-up. Older adolescents may also have more friends who smoke, making it more difficult for them to get the social support they need to quit.
Provider's fidelity to the brief intervention was very good, illustrating the feasibility of incorporating smoking prevention and cessation into routine pediatric practice. Patient acceptance was excellent, and those who received the intervention were more likely to feel that it is the provider's job to address smoking.
The excellent fidelity to the intervention by the peer counselors suggests that young adult ex-smokers can be effectively trained to deliver both prevention and cessation interventions to adolescents in primary care settings. Although peer counselors are not available in most pediatric settings, pediatric clinics might establish a relationship with a local college or graduate program from which counselors could be recruited. These students could be trained in the intervention protocol at their school and could receive course credit and credit for practicum experience in exchange for delivering treatment services within the pediatric practice. Colleges and universities with psychology, social work, and counseling programs may be particularly interested in developing such collaborations with pediatric offices in surrounding communities and taking on the training of students in the intervention protocol, or pediatric clinics could refer interested patients to a local cessation program, which would train their counselors in the protocol. A third option is to train a younger staff member, such as a nurse, to provide the more intensive assistance and follow-up. We were unable to evaluate whether the status of the counselors as ex-smokers was a crucial factor in the success of our intervention.
Recruitment and retention of adolescents have been significant challenges for smoking cessation studies with adolescents. A number of strategies were implemented to maximize recruitment, including labeling the study “Air It Out” to be inclusive of both smokers and nonsmokers, establishing strong working relationships with office staff to facilitate on-site recruitment and feedback to staff regarding progress toward reaching recruitment goals. Strategies implemented to achieve the 99% retention rate included modest but sequentially increasing incentives for completing each assessment, collection of extensive contact information, and personalized letters from the research staff.
Potential limitations include the absence of biochemical validation of smoking status. Although patients were told that they might be asked to breathe into a CO monitor to confirm their smoking status, biochemical validation was not conducted. Because of the more intensive social contact, patients in the PPDI condition may have felt more pressure to report abstinence; a systemic bias for reporting abstinence between PPDI and UC conditions cannot be ruled out. The number of randomized clinics was fairly small, so imbalances of unmeasured covariates could easily occur by chance.
The present study demonstrates the feasibility and short-term efficacy of a novel, pediatric-based smoking intervention delivered by pediatric providers and peer counselors during routine medical care to help adolescent smokers quit and to prevent the initiation of smoking among nonsmokers. Pediatric providers in busy clinical practices can provide assistance to their adolescent patients regarding this critical health behavior in conjunction with peer counselors available from local colleges.
We gratefully acknowledge support for this research by grant R01 CA80254 from the National Institutes of Health, National Cancer Institute.
We also thank the research assistants who collected the data and the pediatric practices and their staff who graciously took part in this study. To the adolescents who agreed to participate we extend our deepest appreciation.
- Accepted August 31, 2007.
- Address correspondence to Lori Pbert, PhD, Division of Preventive and Behavioral Medicine, University of Massachusetts Medical School, 55 Lake Ave North, Worcester, MA 01655. E-mail:
This trial has been registered at www.clinicaltrials.gov (identifier NCT 00435344).
The authors have indicated they have no financial relationships relevant to this article to disclose.
What's Known on This Subject
The American Academy of Pediatrics recommends that pediatricians address smoking with adolescents, both to assist smokers in quitting and to prevent initiation. Although no proven programs exist, interventions based on cognitive behavioral therapy and sensitive to stages of change seem promising.
What This Study Adds
This study evaluated the efficacy of a practice-based smoking prevention and cessation intervention for adolescents delivered by pediatric practices and older peer counselors, which was found to be effective in discouraging initiation among nonsmokers and increasing short-term abstinence among smokers.
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