Evaluation of effectiveness and acceptability of a psychological treatment for smoking cessation combined with a smartphone App: A pilot study.

Despite the increasing number of mobile-based interventions to quit smoking over the last years, few studies have investigated the efficacy of smoking cessation interventions blended with smartphone Apps. The present pilot study aims to examine the preliminary effectiveness and acceptability of a cognitive-behavioral treatment combined with a smartphone App, compared to the same psychological treatment without the App. The sample comprised 206 treatment-seeking smokers, who were assigned to: 1) an experimental group receiving a cognitive-behavioral intervention combined with the "Non Fumo" App (n = 102), and 2) a control group receiving only the cognitive-behavioral intervention to quit smoking (n = 104). Results concerning the primary outcomes showed no significant differences between conditions in point-prevalence abstinence rates at 12-month follow-up (35.30 % in the experimental group vs. 31.70 % in the control group) and in treatment acceptability. Regarding the secondary outcomes, both groups obtained similar point-prevalence abstinence rates at the end of treatment (61.80 % vs. 65.40 %), at 3-month (42.20 % vs. 45.20 %, respectively) and 6-month follow-ups (37.30 % vs. 37.50 %). No significant differences were found between conditions in prolonged abstinence rates at 6-month (35.3 % vs. 35.6 %) and 12-month follow-ups (30.4 % vs. 26.9 %). Overall, good abstinence rates and treatment acceptability were obtained, although there were no significant differences between conditions. More research is needed to establish clear conclusions about the efficacy of psychological smoking cessation treatments blended with smartphone Apps.

The Efficacy of the SinHumo App Combined With a Psychological Treatment to Quit Smoking: A Randomized Clinical Trial.

INTRODUCTION: This study assessed the efficacy of the SinHumo App combined with a cognitive-behavioral smoking cessation treatment on 12-month follow-up abstinence, compared with the same smoking cessation treatment and a control App. AIMS AND METHODS: A sample of 288 treatment-seeking people who smoke were randomized: SinHumo App plus smoking cessation treatment (n = 140) and control App plus smoking cessation treatment (n = 148). The primary outcome was 7-day point prevalence abstinence (PPA) at the 12-month follow-up. Secondary outcomes were abstinence rates at the end of the intervention and 3- and 6-month follow-ups, cigarette per day (CPD) reduction over the 12-month follow-up, intervention engagement, and satisfaction. RESULTS: Intention-to-treat analyses showed nonsignificant differences in self-reported 7-day PPA at the 12-month follow-up (37.1 and 42.6%, respectively; OR = 0.80). No significant differences were found in abstinence at the end of the treatment (68.6 vs. 62.8%) nor on 7-day PPA at 3- (35.7 vs. 45.9%) and 6-month (35.0 vs. 41.2%) follow-up. Complete case and multiple imputation analyses yielded similar results for abstinence outcomes. A significant reduction in CPD across the 12-month follow-up in the subsample of participants who smoked was observed, but nonsignificant differences between conditions were found. Higher engagement with the SinHumo App was a significant predictor of 12-month abstinence. Satisfaction with the intervention was high and similar in both groups. CONCLUSIONS: High abstinence rates over the 12-month follow-up and satisfaction were found in both conditions. The inclusion of the SinHumo App did not improve abstinence rates in the intervention. IMPLICATIONS: Scarce research has examined the long-term efficacy of smoking cessation treatments, including Apps, to support the quitting process. The present randomized controlled trial contributes to the existing literature about including information and communication technologies in behavior change interventions. The development of effective smoking cessation apps and information and communication technologies-based interventions is crucial for reducing the prevalence of smoking, as these interventions have the potential to reach a large number of people who smoke and reduce access-related barriers to treatment.

Dual alcohol and cannabis use in male and female adolescents: Relationships with family variables.

Family dynamics influence adolescents' use of alcohol and other substances, such as cannabis. The aim of this study was to understand the relationship between family variables and alcohol use, dual use of alcohol and cannabis, and non-use in adolescents according to sex. A cross-sectional study was conducted. The sample comprised 879 adolescents (56.4 % boys; M(SD)age = 14.25 (1.88) years). Multinomial regression analysis showed that for boys, the presence of family conflict increased the likelihood of being an alcohol (OR = 1.19) and dual (OR = 1.23) user rather than a non-user. For girls, communication reduced the probability of being an alcohol user (OR = 0.88), and the presence of consequences for breaking rules reduced the probability of being a dual user rather than a non-user (OR = 0.83) or an alcohol user (OR = 0.84). These findings highlight the importance of family prevention of adolescents' substance use, bearing in mind the participants' sex.

Boredom Susceptibility and Quit Smoking: The Role of Anxiety Symptoms.

Boredom is one of the main reported motives for smoking. However, scarce research has examined the relationship between boredom susceptibility and abstinence achievement in treatment-seeking smokers. The aim of this study is to examine the mediating effect of anxiety symptoms in the relationship between boredom susceptibility and abstinence at the end of a smoking cessation treatment. The sample was composed of 481 Spanish smokers who received a cognitive-behavioral treatment to quit (Mage= 45.51, SD = 11.16; 60.6% female). The Boredom Susceptibility subscale of the Sensation Seeking Scale Form-V and the Beck Anxiety Inventory were used. Pearson correlations and mediation analyses were conducted to examine the relationships between the study variables. Boredom susceptibility was significantly and positively correlated to anxiety symptoms, but not to abstinence. Anxiety symptoms were significantly and negatively correlated to abstinence. A significant indirect effect of boredom susceptibility on abstinence at the end of treatment through anxiety symptoms was found. There was no direct relation between boredom susceptibility and abstinence. These findings extend previous literature by showing that higher boredom susceptibility is associated with less likelihood to be abstinent at the end of the treatment through higher anxiety symptoms. These results highlight the relevance of considering the inclusion of boredom and anxiety management techniques in smoking cessation interventions.

Perceived Stress and Smoking Cessation: The Role of Smoking Urges.

Despite the fact that perceived stress is related to abstinence smoking outcomes, no studies have investigated the mediational effect of specific tobacco-related variables on this relationship. This study aimed to explore the indirect effect of perceived stress on abstinence at the end of treatment through smoking urges. The sample comprised 260 treatment-seeking smokers (58.5% female; Mage = 46.00; SD = 11.1) who underwent psychological smoking cessation treatment. The brief version of the Questionnaire of Smoking Urges (QSU) and the Perceived Stress Scale (PSS14) were used. Mediation analyses were conducted in which smoking urges and their dimensions were potential mediators in the relationship between perceived stress and abstinence at the end of treatment. The results showed a non-significant direct effect of perceived stress on abstinence. However, a significant indirect effect was found through smoking urges (QSU-total) and, specifically, through smoking urges associated with the expectation of negative affect relief (QSU-Factor 2). A non-significant indirect effect through smoking urges related to the expectation of tobacco use as a pleasurable experience (QSU-Factor 1) was also found. Analyzing possible mediator variables could contribute to understanding previous conflicting data. These findings point to potential interest in including treatment components targeting perceived stress and smoking urges to improve the effectiveness of smoking cessation treatments.

A Randomized Clinical Trial to Assess the Efficacy of a Psychological Treatment to Quit Smoking Assisted with an App: Study Protocol.

Numerous studies have shown the efficacy of smoking cessation interventions. However, some challenges, such as relapse rates, remain. The availability of information technologies (ICTs) offers promising opportunities to address such challenges. The aim of this paper is to describe the protocol followed to assess the efficacy of a face-to-face cognitive-behavioral intervention for smoking cessation using a smartphone application as a complement, compared with a control group. A single blind, two-arm, randomized controlled trial is proposed (NCT04765813). The participants will be smokers over 18 years old, who smoke at least eight cigarettes per day. Participants will be randomized to one of two conditions, using a 1:1 allocation ratio: (1) cognitive-behavioral smoking cessation treatment along with an App with active therapeutic components (SinHumo App); or (2) cognitive-behavioral treatment along with the use of a control App (without active components). The experimental App will be used during the eight treatment sessions and for 12 months after the end of treatment. The primary outcome measures will be 7-days point-prevalence abstinence at 12-months follow-up. We expect the experimental App to obtain higher abstinence rates at the end of treatment and at one-year post-treatment follow-ups and lower relapse rates, compared to the control App.

Brooding Rumination and Anxiety Sensitivity: Associations With Depressive and Anxiety Symptoms in Treatment-seeking Smokers.

BACKGROUND: This study explores the shared and specific associations of brooding rumination and anxiety sensitivity to depression and anxiety symptomatology in a sample of treatment-seeking smokers. METHODS: The sample was composed of 275 treatment-seeking adult smokers. Hierarchical linear regression analyses were conducted to examine the relations of both variables with depressive and anxiety symptoms. RESULTS: Greater brooding rumination and anxiety sensitivity predicted higher levels of depression and anxiety symptoms. A specific relationship emerged after controlling for comorbid symptoms (depressive or anxiety symptoms) where brooding rumination was associated with depressive symptoms and anxiety sensitivity with anxiety symptoms. CONCLUSIONS: The findings showed that the variables examined are transdiagnostically related to emotional symptoms, but this relationship was symptomatology-specific when controlling for comorbid symptoms (depressive or anxiety symptoms). Due to the impact of affective symptoms on abstinence outcomes, these findings have relevant clinical implications. In the context of smoking cessation treatment, identifying shared and specific vulnerabilities might contribute to tailoring and designing more precise and effective interventions for quitting smoking.

Smoking Cessation Apps: A Systematic Review of Format, Outcomes, and Features.

Smoking cessation interventions are effective, but they are not easily accessible for all treatment-seeking smokers. Mobile health (mHealth) apps have been used in recent years to overcome some of these limitations. Smoking cessation apps can be used in combination with a face-to-face intervention (FFSC-Apps), or alone as general apps (GSC-Apps). The aims of this review were (1) to examine the effects of FFSC-Apps and GSC-Apps on abstinence, tobacco use, and relapse rates; and (2) to describe their features. A systematic review was conducted following the internationally Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Of the total 6016 studies screened, 24 were included, of which nine used GSC-Apps and 15 FFSC-Apps. Eight studies reported significant differences between conditions in smoking cessation outcomes, with three of them being in favor of the use of apps, and two between different point-assessments. Concerning Apps features, most GSC-Apps included self-tracking and setting a quit plan, whereas most of the FFSC-Apps included self-tracking and carbon monoxide (CO) measures. Smartphone apps for smoking cessation could be promising tools. However, more research with an adequate methodological quality is needed to determine its effect. Nevertheless, smartphone apps' high availability and attractiveness represent a great opportunity to reach large populations.

Causes of smoking relapse in the 12 months after smoking cessation treatment: Affective and cigarette dependence-related factors.

Despite advances in smoking cessation treatments, smoking relapse remains common. Experiencing positive or negative affect and cigarette dependence are the most common causes of relapse; however, little is known about the characteristics that increase the risk of relapse from these causes among current treatment-seeking smokers. Thus, this study aimed to identify the most frequent causes of relapse and the individual characteristics that increase the risk of relapse from these causes during a 12-month period after smoking cessation. Participants included 121 treatment-seeking smokers who quit smoking at the end of treatment and relapsed during a 12-month follow-up period (60.3% female;Mage = 42.57, SD = 11.07). Results indicated that the most frequent smoking relapse situations occurred when smokers experienced positive (e.g., being relaxed; 43.0%) or negative (e.g., being angry; 37.2%) affect or cigarette dependence-related situations (e.g., craving; 19.8%). At an individual level, males with a higher level of education and without a psychopharmaceutical prescription had a higher risk of relapsing in positive-affect situations. Smoking the first cigarette at an older age increased the risk of relapse in negative-affect situations. Finally, being younger and less motivated to quit at pretreatment increased the likelihood of relapse in cigarette dependence-related situations. These findings provide detailed information about smoking relapse situations and identify a set of characteristics that might help to improve current relapse-prevention interventions.

Treatment completion and anxiety sensitivity effects on smoking cessation outcomes.

INTRODUCTION: Treatment completion is associated with abstinence outcomes in smoking cessation interventions. Previous research has stated that anxiety sensitivity (AS) is associated with smoking-related variables and smoking-cessation outcomes. To date, research has not examined the interaction between AS and treatment completion on smoking-cessation outcomes over time. This study aims to examine the main and the interactive effects of treatment completion and AS (total score and specific dimensions) on smoking-cessation outcomes at 3-, 6-, and 12-month follow-ups. METHOD: The sample consisted of 210 smokers enrolled in an eight-session smoking-cessation cognitive-behavioral treatment (62.1% women; Mage = 45.2, SD = 11.0). Participants were classified as completers (attended the eight treatment sessions) and non-completers (attended ≤ 7 sessions). Abstinence was biochemically confirmed. RESULTS: Main effects indicated that completers had a higher likelihood of being abstinent over time when compared to non-completers. Regarding AS, those with greater AS-Physical Concerns had lower abstinence rates. Besides, a significant interaction between treatment completion, time and AS-Physical Concerns was found. Particularly, completers with greater AS-Physical Concerns had a higher likelihood of being abstainers than non-completers over time, while no significant differences were found for those with lower AS-Physical Concerns. CONCLUSION: These data highlight the relevance of AS-Physical levels and smoking-cessation treatment completion on abstinence outcomes over time among treatment-seeking smokers.

Specific Relapse Predictors: Could Cognitive-Behavioral Treatment for Smoking Cessation Be Improved?

Relapse remains a frequent and complex phenomenon that is not yet well understood. An under-researched area of study that may provide relevant information concerns the assessment of specific post-treatment variables, rather than the composite measures commonly used to predict smoking relapse. The current study sought to examine the effects of post-treatment smoking-related variables, including withdrawal symptomatology, abstinence self-efficacy, and smoking urgency in negative-affect situations and smoking relapse at the 3 month follow-up. The sample comprised 130 participants who achieved abstinence for at least 24 h through a cognitive-behavioral smoking cessation treatment. Regression analysis was conducted for both composite measures and specific subscales and items. Data showed that composite measures of tobacco withdrawal, self-efficacy, and smoking urgency in negative-affect situations were not significant predictors of smoking relapse. However, the analysis including subscales, and specific items showed that lower self-efficacy in negative-affect-related situations (OR = 1.36) and three withdrawal symptoms-irritability/frustration/anger (OR = 2.99), restlessness/impatience (OR = 1.87), and craving (OR = 2.31)-were significant predictors of relapse. These findings offer new insights into the role of different smoking-related post-treatment variables in short-term relapse. Considering and specifically targeting these variables after achieving abstinence may potentially contribute to reducing smoking relapse.

Correction to: Effects of behavioural activation on substance use and depression: a systematic review.

An amendment to this paper has been published and can be accessed via the original article.

Environmental reward and depressive symptoms in the relationship between avoidance and cigarette dependence in treatment-seeking smokers.

BACKGROUND: The current study sought to further examine the relation between avoidance, environmental reward, depressive symptoms and cigarette dependence. METHOD: The sample included 275 adult treatment-seeking daily smokers (M age = 45.36, SD = 10.96; 61.5% female). To examine the relationships between the study variables, correlation and serial mediation analyses were conducted. RESULTS: A significant positive relationship between cigarette dependence, avoidance, and depressive symptoms, and a negative relationship with environmental reward was found. Mediation analysis revealed a significant indirect pathway from avoidance to cigarette dependence through depressive symptoms; and also a significant indirect serial pathway from avoidance to cigarette dependence through environmental reward and depressive symptoms. CONCLUSIONS: Our findings suggest the importance of avoidance, environmental reward and depressive symptoms in cigarette dependence. Our findings contribute to the understanding of behavioral and psychological factors related to cigarette dependence, which is a well-known barrier to abstinence. Thus, it could be useful to assess and address such variables in the context of smoking-cessation interventions.

Behavioral activation and smoking cessation outcomes: The role of depressive symptoms.

INTRODUCTION: Depressive symptoms are related to smoking cessation outcomes. We examined the effects of behavioral activation (BA), as part of a cognitive behavioral intervention to quit smoking, in terms of abstinence rates according to depressive symptom level. We also analyzed whether BA could differentially benefit participants with higher versus lower anhedonia. METHODS: The sample was composed of 183 smokers (Mage = 45.3; 62.8% female) who participated in a randomized clinical trial assessing the effects of a BA intervention compared to a standard intervention. Smoking outcomes were biochemically confirmed point prevalence abstinence, and abstinence days after treatment during one year follow-up. The intensity of depressive symptomatology and anhedonic symptoms were assessed using the Beck Depression Inventory-II. RESULTS: No differences in abstinence rates were found in relation to depressive symptom level. The BA condition (vs. standard condition) predicted greater abstinence rates (OR = 1.91) in participants with lower scores on depressive symptoms, whereas in participants with higher scores, it did not (OR = 1.17). Moreover, the BA condition predicted greater abstinence rates in participants with lower scores on anhedonia. When examining days of abstinence during the one-year follow-up period, a significant interaction was found between depressive symptoms and treatment condition, favoring the BA condition. CONCLUSION: BA implemented as part of a cognitive behavioral intervention to quit smoking improves long-term abstinence rates, especially among those with fewer depressive symptoms.

Cognitive-behavioral treatment with behavioral activation for smoking cessation: Randomized controlled trial.

INTRODUCTION: Behavioral Activation is a behavioral-based treatment that has been proposed as suitable for smoking cessation, as it simultaneously addresses reinforcement-related variables and also mood management. The aim of this study was to compare the effects of a cognitive-behavioral smoking cessation treatment with components of behavioral activation (SCBSCT-BA) with a standard cognitive-behavioral treatment (SCBSCT), and a wait-list control group (WL). METHOD: The sample was comprised of 275 adults smokers (61.4% females, mean age = 45.36, SD = 10.96). After baseline assessment sessions, participants were randomized (ratio: 2.2.1.) to SCBSCT-BA, SCBSCT, or WL. Active groups received 8 weekly 1-hour face-to-face group sessions. Biochemically verified smoking abstinence and depressive symptoms were assessed at the end of treatment, and at 3-, 6-, and 12-month follow-ups. RESULTS: Significant treatment effects in 7-dayspoint prevalence abstinence rates were found for both active groups at the end of treatment. Abstinence rates at 12-months follow-up were 30% for SCBSCT-BA, and 18% for SCBSCT. Using Multiple Imputation for missing data, regression analysis showed significantly greater ORs for the SCBSCT-BA condition (vs. SCBSCT) at the end of treatment and at 3-months follow-up. At 6-, and 12-months follow-ups, ORs for the SCBSCT-BA condition, although greater, did not reach statistical significance. Multilevel analysis showed that abstinence was related to reductions in depressive symptoms. CONCLUSIONS: SCBSCT-BA obtained positive results at short and medium term. Participants who quit smoking experienced a significant reduction in depressive symptoms. Findings support the benefit of adding BA to a cognitive-behavioral smoking cessation treatment. TRIAL REGISTRATION: www.clinicaltrials.gov NCT02844595.

Effect of Depressive Symptoms and Sex on the Relationship Between Loneliness and Cigarette Dependence: A Moderated Mediation.

Loneliness is a subjective and emotionally unpleasant experience of perceiving insufficient social relationships. Previous research has revealed that loneliness constitutes a psychosocial risk factor for depression, and is also related to unhealthy behaviors such as smoking. This study aims to examine the relation between loneliness, depression, and cigarette dependence, and to explore the role of sex in this relationship. A total sample of 275 adult treatment-seeking daily smokers (Mage = 45.3; 61.5% females) was used. Our results showed a significant correlation between higher scores of loneliness, depressive symptoms, and cigarette dependence. In addition, mediation analysis showed a significant indirect effect of loneliness on cigarette dependence, via depressive symptoms. Regarding the effect of sex, we found that this variable significantly moderated the relationship between depressive symptoms and cigarette dependence. Results of this study extend previous literature by showing that, in treatment seeking smokers, loneliness is a significant predictor of depressive symptoms, and through this relation, it predicts cigarette dependence. Additionally, sex was a significant moderator of this relation. These findings have several clinical implications, and also contribute to the understanding of cigarette dependence, which is a well-known barrier for smoking cessation.

Effects of behavioural activation on substance use and depression: a systematic review.

INTRODUCTION: Substance use and depression co-occurrence is a frequent phenomenon and an important public health concern. Given the clinical implications and the high prevalence of both disorders, effective interventions are needed. METHODS: The aim of this study is to review Behavioural Activation (BA) intervention effects to improve substance use behaviour and depression. A systematic review was conducted using MEDLINE, EMBASE, and PsycINFO. The Effective Public Health Practice Project Quality Assessment Tool (EPHPP) was used to assess the methodological quality of included studies. Two authors independently screened titles and abstracts, reviewed selected studies, and extracted data. RESULTS: Of the 7286 studies identified, eight met inclusion criteria. Designs of the studies included six randomized controlled trials (RCTs), and two pre-post design studies. One trial received weak methodological quality, six moderate, and one strong. Three studies addressed smoking behaviour; two targeted opiate dependence; two focused on alcohol/drug dependence; and, one on crystal methamphetamine abuse. Results showed that BA had a positive effect on substance use outcomes in seven of the eight reviewed studies, and improved depression over time in six studies. CONCLUSIONS: Although studies conducted so far are limited by their heterogeneity and sample sizes, results are promising. There is a need of well controlled and powered studies to establish and to confirm the effectiveness of BA for the treatment of substance use and depression. Future studies should include stronger methodological designs, larger sample sizes, and long-term follow-ups. TRIAL REGISTRATION: PROSPERO registration number: CRD42016039412 .

Depressive symptoms in the trajectory of craving during smoking cessation treatment: A latent growth curve model.

BACKGROUND: Depressive symptoms and craving are related to smoking maintenance; however, little is known about the association between trajectories of depressive symptoms and smoking craving after quitting. OBJECTIVES: We examined if depressive symptom change relates to change in craving following smoking cessation treatment. METHODS: Participants were 362 (64.1% female; 35.9% male) adult treatment seeking smokers who quit smoking after treatment. Depressive symptoms and craving trajectories were evaluated during smoking cessation treatment until 6 months follow-up. A latent growth curve model was used to study the correlation between trajectories. RESULTS: Depressive symptoms and smoking craving reduced significantly after quitting. Change in depressive symptoms was significantly related to change in craving symptoms over time. CONCLUSIONS: Quitting smoking was related to a reduction in depressive symptoms and craving. Clinically, the reduction of depressive symptoms is associated with reduce craving. The data suggest depression plays an important role in craving change following treatment.

Health-related quality of life among smoking relapsers.

BACKGROUND: Previous studies have shown that smoking is associated with health-related quality of life (HRQoL) impairment. In order to evaluate HRQoL in a sample of Spanish relapsers, a cross-sectional study was conducted. METHOD: The sample was made up of 775 smokers who had relapsed after a period of abstinence. HRQoL was evaluated using the Euro-Qol questionnaire (EQ-5D); through the descriptive profile, the EQ-5D index and the visual analogue scale (EQ-VAS). RESULTS: Higher nicotine dependence was related to worse HRQL. According to the EQ-VAS, higher daily cigarette consumption and more years smoking were related to worse perceived health. In the EQ-5D those who had quit smoking in the previous year perceived worse health. Mobility and anxiety / depression are the dimensions affected by smoking. Those who are more nicotine dependent (OR = 2.29) and have been smoking for longer (OR = 4.12) are more likely to have mobility problems; and those who are nicotine dependent (OR = 1.85) and relapsed more than a year ago (OR = 0.63), are more likely to experience anxiety / depression. CONCLUSIONS: Nicotine dependence demonstrated a determining effect on HRQOL deterioration in smokers who have relapsed.

The Interaction of Depressive Symptoms and Hazardous Drinking in Relation to Tobacco Craving Among Treatment Seeking Depressed Smokers: Sex Differences.

OBJECTIVES: The present study sought to address whether there is sex effect in the interactive effect between depressive symptoms and hazardous drinking in the prediction of smoking craving after cognitive-behavioral smoking cessation treatment among those with at least mild depression. METHODS: Participants (n = 114, mean age 42.0, SD = 9.73, 64% women) were treatment-seeking smokers who attended 6 weekly 1-hour sessions involving psychological treatment for cessation. Participants reported depressive symptoms and alcohol use at baseline and reported craving at baseline and after treatment. RESULTS: Results indicated that there was a statistically significant 3-way interaction (depression by alcohol use by sex) for smoking craving (B = -0.30, standard error [SE] = 0.14, P = 0.042) and appetitive craving (B = -.21, SE = 0.09, P = 0.031), but not negative reinforcement craving. The form of the significant interactions indicted that higher levels of depressive symptoms and alcohol use were related to greater levels of craving at the end of treatment only among men. CONCLUSIONS: The current findings provide novel empirical evidence suggesting that there is a clinically relevant interplay between depressive symptoms and alcohol use regarding general craving and appetitive craving among male treatment-seeking smokers. Although the present results should be replicated in larger samples, this type of research can inform the development of sex-specific interventions for smoking cessation.