***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Background Advances in technology allowed the development of a novel smoking cessation program delivered by video messages sent to mobile phones . This social cognitive theory-based intervention ( called “ STUB IT ” ) used observational learning via short video diary messages from role models going through the quitting process to teach behavioral change techniques . Objective The objective of our study was to assess the effectiveness of a multimedia mobile phone intervention for smoking cessation . Methods A r and omized controlled trial was conducted with 6-month follow-up . Participants had to be 16 years of age or over , be current daily smokers , be ready to quit , and have a video message-capable phone . Recruitment targeted younger adults predominantly through radio and online advertising . Registration and data collection were completed online , prompted by text messages . The intervention group received an automated package of video and text messages over 6 months that was tailored to self-selected quit date , role model , and timing of messages . Extra messages were available on dem and to beat cravings and address lapses . The control group also set a quit date and received a general health video message sent to their phone every 2 weeks . Results The target sample size was not achieved due to difficulty recruiting young adult quitters . Of the 226 r and omized participants , 47 % ( 107/226 ) were female and 24 % ( 54/226 ) were Maori ( indigenous population of New Zeal and ) . Their mean age was 27 years ( SD 8.7 ) , and there was a high level of nicotine addiction . Continuous abstinence at 6 months was 26.4 % ( 29/110 ) in the intervention group and 27.6 % ( 32/116 ) in the control group ( P = .8 ) . Feedback from participants indicated that the support provided by the video role models was important and appreciated . Conclusions This study was not able to demonstrate a statistically significant effect of the complex video messaging mobile phone intervention compared with simple general health video messages via mobile phone . However , there was sufficient positive feedback about the ease of use of this novel intervention , and the support obtained by observing the role model video messages , to warrant further investigation . Trial registration Australian New Zeal and Clinical Trials Registry Number : ACTRN12606000476538 ; http://www.anzctr.org.au/trial_view.aspx?ID=81688 ( Archived by WebCite at http://www.webcitation.org/5umMU4sZi Summary We evaluated the effectiveness of a mobile phone text-messaging based smoking cessation intervention package among Chinese adolescent smokers . Students aged 16–19 years were recruited from six vocational high schools located in Shanghai . We assigned the six schools to an intervention group or a control group by cluster r and omization . The 92 participants in the intervention group were given tailored information via mobile phone text-messaging for 12 weeks . The 87 participants in the control group were provided with a self-help pamphlet about smoking cessation instead . After the intervention , attitudes towards the disadvantages of smoking were significantly improved , and the level of nicotine dependence and cigarette dependence significantly decreased in the intervention group . The intervention group had a relatively higher self-reported 7-day abstinence compared to the control group and 30-day abstinence , but the differences were not significant . However , the intervention group had a significantly higher rate of smoking reduction ( 66 % vs. 35 % ) and moving forward in quitting stages ( 52 % vs. 18 % ) compared to the control group . The interactive and tailored assistance provided by the mobile phone text-messaging  was effective in smoking behaviour intervention in Chinese adolescent smokers While sex differences in the nicotine withdrawal ( NW ) symptoms and craving ( NC ) have been extensively described in adult cigarette smokers , few studies have investigated these phenomena in adolescents . We investigated the effect of gender and hormonal contraception ( HC ) on NW and NC during the first 14 days of cessation in adolescent smokers using data from a r and omized , placebo-controlled  , double-blind trial of the transdermal nicotine replacement therapy for smoking cessation . Analyses showed similar levels of NW severity in males and females , regardless of HC use . However , significantly higher NC was observed in females compared to males , ( 2.22+/-0.12 vs. 1.65+/-1.14 ; p=0.003 ) . Further , females not using HC reported the highest level of NC ( 2.38+/-0.16 ) followed by females using HC ( 2.08+/-0.25 ) and males ( 1.71+/-0.16 ; p=0.007 ) . The current findings suggest that adolescent females experience similar NW severity to males , but have stronger NC . Further , the use of hormonal contraceptives may impact the severity of craving . Addressing these different symptoms in adolescents may be useful in increasing smoking cessation rates in this special population of smokers Background Young adult smokers are a challenging group to engage in smoking cessation interventions . With wide reach and engagement among users , Facebook offers opportunity to engage young people in socially supportive communities for quitting smoking and sustaining abstinence . Objective We developed and tested initial efficacy , engagement , and acceptability of the Tobacco Status Project , a smoking cessation intervention for young adults delivered within Facebook . Methods The intervention was based on the US Public Health Service Clinical Practice Guidelines and the Transtheoretical Model and enrolled participants into study -run 3-month secret Facebook groups matched on readiness to quit smoking . Cigarette smokers ( N=79 ) aged 18 - 25 , who used Facebook on most days , were recruited via Facebook .  All participants received the intervention and were r and omized to one of three monetary incentive groups tied to engagement ( commenting in groups ) . Assessment s were completed at baseline , 3- , 6- , and 12-months follow-up . Analyses examined retention , smoking outcomes over 12 months ( 7-day point prevalence abstinence , ≥50 % reduction in cigarettes smoked , quit attempts and strategies used , readiness to quit ) , engagement , and satisfaction with the intervention . Results Retention was 82 % ( 65/79 ) at 6 months and 72 % ( 57/79 ) at 12 months . From baseline to 12-months follow-up , there was a significant increase in the proportion prepared to quit ( 10/79 , 13 % ; 36/79 , 46 % , P<.001 ) . Over a third ( 28/79 , 35 % ) reduced their cigarette consumption by 50 % or greater , and 66 % ( 52/79 ) made at least one 24-hour quit attempt during the study . In an intent-to-treat analysis , 13 % ( 10/79 ) self-reported 7-day abstinence ( 6/79 , 8 % verified biochemically ) at 12-months follow-up . In their quit attempts , 11 % ( 9/79 ) used a nicotine replacement therapy approved by the Food and Drug Administration , while 18 % ( 14/79 ) used an electronic nicotine delivery system to quit ( eg , electronic cigarette ) . A majority ( 48/79 , 61 % ) commented on at least one Facebook post , with more commenting among those with biochemically verified abstinence at 3 months ( P=.036 ) and those r and omized to receive a personal monetary incentive ( P=.015 ) . Over a third of participants ( 28/79 , 35 % ) reported reading most or all of the Facebook posts . Highest acceptability ratings of the intervention were for post ease ( 57/79 , 72 % ) and thinking about what they read ( 52/79 , 66 % ) ; 71 % ( 56/79 ) recommended the program to others . Only 5 participants attended the optional cognitive-behavioral counseling sessions , though their attendance was high ( 6/7 sessions overall ) and the sessions were rated as easy to underst and , useful , and helpful ( all 90 - 100 % agreed ) . Conclusions A Facebook quit smoking intervention is attractive and feasible to deliver , and early efficacy data are encouraging . However , the 1.5-fold greater use of electronic cigarettes over nicotine replacement products for quitting is concerning BACKGROUND Varenicline is approved as an aid to smoking cessation in adults aged > or = 18 years . OBJECTIVE The goal of this study was to characterize the multiple-dose pharmacokinetics , safety , and tolerability of varenicline in adolescent smokers . METHODS This multicenter , r and omized , double-blind , placebo-controlled , parallel-group study enrolled healthy 12- to 16-year-old smokers ( > or =3 cigarettes daily ) into high-body-weight ( > 55 kg ) and low-body-weight ( < or = 55 kg ) groups . Subjects were r and omized to receive 14 days of treatment with a high dose of varenicline , a low dose of varenicline , or placebo . The varenicline doses in the high-body-weight group were 1 mg BID and 0.5 mg BID ; the varenicline doses in the low-body-weight group were 0.5 mg BID and 0.5 mg once daily . The apparent renal clearance ( CL/F ) and volume of distribution ( V/F ) of varenicline and the effect of body weight on these parameters were estimated using nonlinear mixed-effects modeling . RESULTS The high-body-weight group consisted of 35 subjects ( 65.7 % male ; 77.1 % white ; mean age , 15.2 years ) . The low-body-weight group consisted of 37 subjects ( 37.8 % male ; 48.6 % white ; mean age , 14.3 years ) . The pharmacokinetic parameters of varenicline were dose proportional over the dose range from 0.5 to 2 mg/d . The CL/F for a 70-kg adolescent was 10.4 L/h , comparable to that in a 70-kg adult . The estimated varenicline V/F was decreased in individuals of small body size , thus predicting a varenicline C(max ) approximately 30 % greater in low-body-weight subjects than in high-body-weight subjects . In high-body-weight subjects , steady-state varenicline exposure , as represented by the AUC(0 - 24 ) , was 197.0 ng . h/mL for varenicline 1 mg BID and 95.7 ng . h/mL for varenicline 0.5 mg BID , consistent with values reported previously in adult smokers at the equivalent doses . In low-body-weight subjects , varenicline exposure was 126.3 ng . h/mL for varenicline 0.5 mg BID and 60.1 ng . h/mL for varenicline 0.5 mg once daily , values at the lower end of the range observed previously in adults at doses of 1 mg BID and 0.5 mg BID , respectively . Among high-body-weight subjects , adverse events ( AEs ) were reported by 57.1 % of subjects in both the high- and low-dose varenicline groups and by 14.3 % of subjects in the placebo group ; among low-body-weight subjects , AEs were reported by 64.3 % , 73.3 % , and 12.5 % of subjects in the high-dose varenicline , low-dose varenicline , and placebo groups , respectively . The most common AEs were nausea , headache , vomiting , and dizziness . Psychiatric AEs that were considered treatment related included abnormal dreams in 2 subjects and mild , transient anger in 1 subject . Of the AEs reported by > or = 1 subject in any treatment group , > or = 92 % were mild in intensity . No subject discontinued the study because of an AE . CONCLUSIONS Varenicline steady-state exposure in study subjects weighing > 55 kg was similar to that observed previously in adults . The body-weight effect on varenicline pharmacokinetics , which result ed in higher exposure in individuals of smaller body size ( < or = 55 kg ) , was adequately offset by administration of half the varenicline dose recommended in adults . Varenicline was generally well tolerated during the 14-day treatment period . Clinical Trials Identification Number : NCT00463918 This study evaluates a  youth subject-directed smoking prevention and cessation program titled Breathe Easy ! The program was delivered at two sites and a  control group was recruited from two additional sites . Surveys were administered prior to the program and either 1 month or 6 months after completion at the exposure sites . The same survey administration procedure was used as the control . After controlling for invalid responses and including only those that completed both surveys , 251 exposure subjects and 159 control subjects remained for analysis . At sites with 1-month follow-up , no significant difference was noted between intervention and control groups . At the sites with 6-month follow-up , prevalence dropped from 18.7 % to 8.9 % , which is statistically significant , while at the control site prevalence changed from 14.1 % to 9.4 % , which is not significant . Additional outcomes examined in the exposed group showed trends toward smoking cessation and prevention at higher rates than those of the unexposed group BACKGROUND Motivational interviewing ( MI ) is widely used for adolescent smoking cessation but empirical support for this approach is mixed . METHODS Adoles 
    Output:
    
Studies of pharmacotherapies reported some adverse events considered related to study treatment , though most were mild , whereas no adverse events were reported in studies of behavioural interventions .
There is limited evidence that either behavioural support or smoking cessation medication increases the proportion of young people that stop smoking  in the long-term .
Findings are most promising for group-based behavioural interventions , but evidence remains limited for all intervention types .