Eline Suzanne Smit

Predictors of attempts to stop smoking and their success in adult general population samples: a systematic review.

AIMS To identify the predictors of attempts to stop smoking and the predictors of quit attempt success in adult general population samples. METHODS We performed an electronic search of EMBASE, Pubmed, Web of Science, PsychINFO and the Cochrane Tobacco Addiction Group specialized register for articles that examined, in prospective adult general population samples, predictors of quit attempts and the success of quit attempts. Experts were contacted for knowledge of other relevant studies. Eight studies met the inclusion criteria and results were extracted independently by two researchers. RESULTS There was considerable methodological heterogeneity between studies. Motivational factors dominated the prediction of quit attempts, whereas only cigarette dependence consistently predicted success after an attempt had been made. Social grade also appeared to predict success but was only examined in two studies. None of the other socio-demographic factors consistently predicted making a quit attempt or success. CONCLUSIONS Population-level studies from a number of countries show that past quit attempts and measures of motivation to stop are highly predictive of quit attempts, whereas only measures of dependence are consistently predictive of success of those attempts. Gender, age and marital status and educational level are not related consistently to quit attempts or quit success across countries.

Cost-Effectiveness and Cost-Utility of Internet-Based Computer Tailoring for Smoking Cessation

Background Although effective smoking cessation interventions exist, information is limited about their cost-effectiveness and cost-utility. Objective To assess the cost-effectiveness and cost-utility of an Internet-based multiple computer-tailored smoking cessation program and tailored counseling by practice nurses working in Dutch general practices compared with an Internet-based multiple computer-tailored program only and care as usual. Methods The economic evaluation was embedded in a randomized controlled trial, for which 91 practice nurses recruited 414 eligible smokers. Smokers were randomized to receive multiple tailoring and counseling (n=163), multiple tailoring only (n=132), or usual care (n=119). Self-reported cost and quality of life were assessed during a 12-month follow-up period. Prolonged abstinence and 24-hour and 7-day point prevalence abstinence were assessed at 12-month follow-up. The trial-based economic evaluation was conducted from a societal perspective. Uncertainty was accounted for by bootstrapping (1000 times) and sensitivity analyses. Results No significant differences were found between the intervention arms with regard to baseline characteristics or effects on abstinence, quality of life, and addiction level. However, participants in the multiple tailoring and counseling group reported significantly more annual health care–related costs than participants in the usual care group. Cost-effectiveness analysis, using prolonged abstinence as the outcome measure, showed that the mere multiple computer-tailored program had the highest probability of being cost-effective. Compared with usual care, in this group €5100 had to be paid for each additional abstinent participant. With regard to cost-utility analyses, using quality of life as the outcome measure, usual care was probably most efficient. Conclusions To our knowledge, this was the first study to determine the cost-effectiveness and cost-utility of an Internet-based smoking cessation program with and without counseling by a practice nurse. Although the Internet-based multiple computer-tailored program seemed to be the most cost-effective treatment, the cost-utility was probably highest for care as usual. However, to ease the interpretation of cost-effectiveness results, future research should aim at identifying an acceptable cutoff point for the willingness to pay per abstinent participant.

Effectiveness of a Web-Based Multiple Tailored Smoking Cessation Program: A Randomized Controlled Trial Among Dutch Adult Smokers

Background Distributing a multiple computer-tailored smoking cessation intervention through the Internet has several advantages for both provider and receiver. Most important, a large audience of smokers can be reached while a highly individualized and personal form of feedback can be maintained. However, such a smoking cessation program has yet to be developed and implemented in the Netherlands. Objective To investigate the effects of a Web-based multiple computer-tailored smoking cessation program on smoking cessation outcomes in a sample of Dutch adult smokers. Methods Smokers were recruited from December 2009 to June 2010 by advertising our study in the mass media and on the Internet. Those interested and motivated to quit smoking within 6 months (N = 1123) were randomly assigned to either the experimental (n = 552) or control group (n = 571). Respondents in the experimental group received the fully automated Web-based smoking cessation program, while respondents in the control group received no intervention. After 6 weeks and after 6 months, we assessed the effect of the intervention on self-reported 24-hour point prevalence abstinence, 7-day point prevalence abstinence, and prolonged abstinence using logistic regression analyses. Results Of the 1123 respondents, 449 (40.0%) completed the 6-week follow-up questionnaire and 291 (25.9%) completed the 6-month follow-up questionnaire. We used a negative scenario to replace missing values. That is, we considered respondents lost to follow-up to still be smoking. The computer-tailored program appeared to have significantly increased 24-hour point prevalence abstinence (odds ratio [OR] 1.85, 95% confidence interval [CI] 1.30–2.65), 7-day point prevalence abstinence (OR 2.17, 95% CI 1.44–3.27), and prolonged abstinence (OR 1.99, 95% CI 1.28–3.09) rates reported after 6 weeks. After 6 months, however, no intervention effects could be identified. Results from complete-case analyses were similar. Conclusions The results presented suggest that the Web-based computer-tailored smoking cessation program had a significant effect on abstinence reported after a 6-week period. At the 6-month follow-up, however, no intervention effects could be identified. This might be explained by the replacement of missing values on the primary outcome measures due to attrition using a negative scenario. While results were similar when using a less conservative scenario (ie, complete-case analyses), the results should still be interpreted with caution. Further research should aim at identifying strategies that will prevent high attrition in the first place and, subsequently, to identify the best strategies for dealing with missing data when studies have high attrition rates. Trial Registration Dutch Trial Register NTR1351; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1351 (Archived by WebCite at http://www.webcitation.org/67egSTWrz)

The role of desire, duty and intention in predicting attempts to quit smoking

AIMS Motivation to quit smoking predicts quit attempts, although little is known about the role played by its different aspects. This study assessed the predictive value of desire, duty and intention to quit, three different aspects of motivation. DESIGN A longitudinal study was conducted involving a nationally representative sample of smokers assessed at baseline and 3 and 6 months later. Baseline assessment took place by face-to-face computer-assisted interviews; follow-up assessments by postal questionnaires. SETTING England. PARTICIPANTS From April 2008 to June 2009, a total of 5593 adult smokers were recruited; 1263 were followed-up at 3 months and 1096 at 6 months. MEASUREMENTS Three dichotomous measures of motivation to quit (wanting to quit, believing one ought to quit, intention to quit soon) were taken at baseline. Whether a subsequent quit attempt was made was recorded at 3- and 6-month follow-up. FINDINGS More smokers believed they ought to quit smoking than wanted to or intended to soon (39.0, 29.3 and 23.5%, respectively). Desire and intention were independent predictors of quit attempts at both follow-ups, whereas combining them did not add predictive value and duty was not a predictor. While the predictive value of desire or intention alone disappeared when accompanied by duty, their combination was robust against its negative effect. CONCLUSIONS Desire and intention independently positively predict quit attempts, while duty appears to mitigate their effect. It would be worth monitoring all three aspects of motivation when evaluating the impact of smoking cessation interventions on motivation to quit.

Economic evaluation of a web-based tailored lifestyle intervention for adults: findings regarding cost-effectiveness and cost-utility from a randomized controlled trial

Background Different studies have reported the effectiveness of Web-based computer-tailored lifestyle interventions, but economic evaluations of these interventions are scarce. Objective The objective was to assess the cost-effectiveness and cost-utility of a sequential and a simultaneous Web-based computer-tailored lifestyle intervention for adults compared to a control group. Methods The economic evaluation, conducted from a societal perspective, was part of a 2-year randomized controlled trial including 3 study groups. All groups received personalized health risk appraisals based on the guidelines for physical activity, fruit intake, vegetable intake, alcohol consumption, and smoking. Additionally, respondents in the sequential condition received personal advice about one lifestyle behavior in the first year and a second behavior in the second year; respondents in the simultaneous condition received personal advice about all unhealthy behaviors in both years. During a period of 24 months, health care use, medication use, absenteeism from work, and quality of life (EQ-5D-3L) were assessed every 3 months using Web-based questionnaires. Demographics were assessed at baseline, and lifestyle behaviors were assessed at both baseline and after 24 months. Cost-effectiveness and cost-utility analyses were performed based on the outcome measures lifestyle factor (the number of guidelines respondents adhered to) and quality of life, respectively. We accounted for uncertainty by using bootstrapping techniques and sensitivity analyses. Results A total of 1733 respondents were included in the analyses. From a willingness to pay of €4594 per additional guideline met, the sequential intervention (n=552) was likely to be the most cost-effective, whereas from a willingness to pay of €10,850, the simultaneous intervention (n=517) was likely to be most cost-effective. The control condition (n=664) appeared to be preferred with regard to quality of life. Conclusions Both the sequential and the simultaneous lifestyle interventions were likely to be cost-effective when it concerned the lifestyle factor, whereas the control condition was when it concerned quality of life. However, there is no accepted cutoff point for the willingness to pay per gain in lifestyle behaviors, making it impossible to draw firm conclusions. Further economic evaluations of lifestyle interventions are needed. Trial Registration Dutch Trial Register NTR2168; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2168 (Archived by WebCite at http://www.webcitation.org/6MbUqttYB).

Influence of recruitment strategy on the reach and effect of a web-based multiple tailored smoking cessation intervention among Dutch adult smokers

This study investigated the influence of two different recruitment strategies on the reach and effect of a web-based multiple tailored smoking cessation program. From May 2009 until June 2010, Dutch adult smokers were recruited via mass media or general practices. Those who completed the baseline questionnaire were followed up during 6 weeks (two follow-ups). Differences between the two samples were assessed regarding baseline characteristics, retention rates, quit attempts and 24-hour point prevalence abstinence. Smokers recruited via general practices (N = 409) were significantly lower educated, less addicted, more motivated to quit smoking and to maintain non-smoking, more often female and more often suffering from cardiovascular or respiratory diseases than mass media respondents (N = 1154). They showed higher retention rates and were more likely to report a quit attempt (64.3 versus 50.7%) and abstinence (43.3 versus 33.1%). More respondents could be recruited via mass media, while general practices respondents showed higher retention rates and were more successful in quitting smoking, though these effects became non-significant when controlling for experimental condition and baseline differences. The choice for a particular recruitment strategy appeared to determine the number and type of smokers recruited and might consequently influence the interventions potential public health impact.

An economic evaluation of a video- and text-based computer-tailored intervention for smoking cessation: a cost-effectiveness and cost-utility analysis of a randomized controlled trial

Background Although evidence exists for the effectiveness of web-based smoking cessation interventions, information about the cost-effectiveness of these interventions is limited. Objective The study investigated the cost-effectiveness and cost-utility of two web-based computer-tailored (CT) smoking cessation interventions (video- vs. text-based CT) compared to a control condition that received general text-based advice. Methods In a randomized controlled trial, respondents were allocated to the video-based condition (N = 670), the text-based condition (N = 708) or the control condition (N = 721). Societal costs, smoking status, and quality-adjusted life years (QALYs; EQ-5D-3L) were assessed at baseline, six-and twelve-month follow-up. The incremental costs per abstinent respondent and per QALYs gained were calculated. To account for uncertainty, bootstrapping techniques and sensitivity analyses were carried out. Results No significant differences were found in the three conditions regarding demographics, baseline values of outcomes and societal costs over the three months prior to baseline. Analyses using prolonged abstinence as outcome measure indicated that from a willingness to pay of €1,500, the video-based intervention was likely to be the most cost-effective treatment, whereas from a willingness to pay of €50,400, the text-based intervention was likely to be the most cost-effective. With regard to cost-utilities, when quality of life was used as outcome measure, the control condition had the highest probability of being the most preferable treatment. Sensitivity analyses yielded comparable results. Conclusion The video-based CT smoking cessation intervention was the most cost-effective treatment for smoking abstinence after twelve months, varying the willingness to pay per abstinent respondent from €0 up to €80,000. With regard to cost-utility, the control condition seemed to be the most preferable treatment. Probably, more time will be required to assess changes in quality of life. Future studies with longer follow-up periods are needed to investigate whether cost-utility results regarding quality of life may change in the long run. Trial Registration Nederlands Trial Register NTR3102

Does a typical contemplator exist? Three clusters of smokers in contemplation

The aim of this study is to test whether subtypes exist among smokers in contemplation. Data from 194 adult smokers that participated in a randomized controlled trial testing the effectiveness of a computer-tailored smoking cessation program in Dutch general practices were used for secondary analysis. Cluster analysis was conducted based on baseline scores on pros and cons of quitting and self-efficacy to quit. Clusters were cross-sectionally compared for demographic variables and smoking characteristics with analyses of variance (ANOVA) and Chi-square tests. Logistic and multinomial regression analyses were used for longitudinal comparison for smoking behavior and stage of change at 6 months follow-up. Three clusters were identified: Early, Progressing and Disengaged Contemplators. Clusters differed significantly on all clustering variables (P < 0.001). Disengaged smokers were significantly less addicted than Early Contemplators. Cluster membership was not predictive of outcome measures. No subtype was identified representing the Classic Contemplator, scoring high on both pros and cons of quitting and low on self-efficacy, as found in previous studies among US samples. The predictive validity of the clusters found was limited.

Results of the PAS Study: A Randomized Controlled Trial Evaluating the Effectiveness of a Web-Based Multiple Tailored Smoking Cessation Program Combined With Tailored Counseling by Practice Nurses

ABSTRACT This study investigated the effects of Web-based multiple computer tailoring and counseling by a practice nurse (MTC) compared with computer tailoring without counseling (MT) and usual care (UC) on smoking cessation rates, via a randomized controlled trial with 414 Dutch adult smokers, recruited by 91 practice nurses from May 2009 to June 2010. Logistic multilevel regression analyses were conducted with 24-hour point prevalence, 7-day point prevalence, and prolonged abstinence after 6 and 12 months as dependent variables and experimental condition as the independent variable. After 6 and 12 months, 38% and 56% of respondents were followed up, respectively. At both follow-ups, no main effects of the interventions could be identified when comparing them with care as usual and with each other—neither in analyses using available data nor in analyses using a negative scenario in which respondents lost to follow-up were considered to still be smoking. A Web-based multiple computer-tailored smoking cessation program combined with a single face-to-face counseling session by a practice nurse may not be more effective than this computer-tailored program alone or than usual smoking cessation care in the general practice setting. Yet before concluding that the addition of counseling to Web-based computer tailoring cannot be successful, more research needs to be conducted to identify the optimal number of counseling sessions to be combined with the Web-based program and to how to best attune the two modalities.

Combining intensive practice nurse counselling or brief general practitioner advice with varenicline for smoking cessation in primary care: Study protocol of a pragmatic randomized controlled trial

INTRODUCTION Combining behavioural support and pharmacotherapy is most effective for smoking cessation and recommended in clinical guidelines. Despite that smoking cessation assistance from the general practitioner can be effective, dissemination of clinical practice guidelines and efforts on upskilling has not lead to the routine provision of smoking cessation advice among general practitioners. Intensive counselling from the practice nurse could contribute to better smoking cessation rates in primary care. However, the effectiveness of intensive counselling from a practice nurse versus usual care from a general practitioner in combination with varenicline is still unknown. MATERIALS AND METHODS A pragmatic randomized controlled trial was conducted comparing: (a) intensive individual counselling delivered by a practice nurse and (b) brief advice delivered by a general practitioner; both groups received 12-weeks of open-label varenicline. A minimum of 272 adult daily smoking participants were recruited and treated in their routine primary care setting. The primary outcome was defined as prolonged abstinence from weeks 9 to 26, biochemically validated by exhaled carbon monoxide. Data was analysed blinded according to the intention-to-treat principle and participants with missing data on their smoking status at follow-up were counted as smokers. Secondary outcomes included: one-year prolonged abstinence, short-term incremental cost-effectiveness, medication adherence, and baseline predictors of successful smoking cessation. DISCUSSION This trial is the first to provide scientific evidence on the effectiveness, cost-effectiveness, and potential mechanisms of action of intensive practice nurse counselling combined with varenicline under real-life conditions. This paper explains the methodology of the trial and discusses the pragmatic and/or explanatory design aspects. TRIAL REGISTRATION Dutch Trial Register NTR3067.