Acceptability and effectiveness of opportunistic referral of smokers to telephone cessation advice from a nurse: a randomised trial in Australian general practice

Strategies to improve smoking cessation rates in primary care

BACKGROUND

Primary care is an important setting in which to treat tobacco addiction. However, the rates at which providers address smoking cessation and the success of that support vary. Strategies can be implemented to improve and increase the delivery of smoking cessation support (e.g. through provider training), and to increase the amount and breadth of support given to people who smoke (e.g. through additional counseling or tailored printed materials).

OBJECTIVES

To assess the effectiveness of strategies intended to increase the success of smoking cessation interventions in primary care settings. To assess whether any effect that these interventions have on smoking cessation may be due to increased implementation by healthcare providers.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group's Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, and trial registries to 10 September 2020.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) and cluster-RCTs (cRCTs) carried out in primary care, including non-pregnant adults. Studies investigated a strategy or strategies to improve the implementation or success of smoking cessation treatment in primary care. These strategies could include interventions designed to increase or enhance the quality of existing support, or smoking cessation interventions offered in addition to standard care (adjunctive interventions). Intervention strategies had to be tested in addition to and in comparison with standard care, or in addition to other active intervention strategies if the effect of an individual strategy could be isolated. Standard care typically incorporates physician-delivered brief behavioral support, and an offer of smoking cessation medication, but differs across studies. Studies had to measure smoking abstinence at six months' follow-up or longer.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods. Our primary outcome - smoking abstinence - was measured using the most rigorous intention-to-treat definition available. We also extracted outcome data for quit attempts, and the following markers of healthcare provider performance: asking about smoking status; advising on cessation; assessment of participant readiness to quit; assisting with cessation; arranging follow-up for smoking participants. Where more than one study investigated the same strategy or set of strategies, and measured the same outcome, we conducted meta-analyses using Mantel-Haenszel random-effects methods to generate pooled risk ratios (RRs) and 95% confidence intervals (CIs).

MAIN RESULTS

We included 81 RCTs and cRCTs, involving 112,159 participants. Fourteen were rated at low risk of bias, 44 at high risk, and the remainder at unclear risk. We identified moderate-certainty evidence, limited by inconsistency, that the provision of adjunctive counseling by a health professional other than the physician (RR 1.31, 95% CI 1.10 to 1.55; I2 = 44%; 22 studies, 18,150 participants), and provision of cost-free medications (RR 1.36, 95% CI 1.05 to 1.76; I2 = 63%; 10 studies,7560 participants) increased smoking quit rates in primary care. There was also moderate-certainty evidence, limited by risk of bias, that the addition of tailored print materials to standard smoking cessation treatment increased the number of people who had successfully stopped smoking at six months' follow-up or more (RR 1.29, 95% CI 1.04 to 1.59; I2 = 37%; 6 studies, 15,978 participants). There was no clear evidence that providing participants who smoked with biomedical risk feedback increased their likelihood of quitting (RR 1.07, 95% CI 0.81 to 1.41; I2 = 40%; 7 studies, 3491 participants), or that provider smoking cessation training (RR 1.10, 95% CI 0.85 to 1.41; I2 = 66%; 7 studies, 13,685 participants) or provider incentives (RR 1.14, 95% CI 0.97 to 1.34; I2 = 0%; 2 studies, 2454 participants) increased smoking abstinence rates. However, in assessing the former two strategies we judged the evidence to be of low certainty and in assessing the latter strategies it was of very low certainty. We downgraded the evidence due to imprecision, inconsistency and risk of bias across these comparisons. There was some indication that provider training increased the delivery of smoking cessation support, along with the provision of adjunctive counseling and cost-free medications. However, our secondary outcomes were not measured consistently, and in many cases analyses were subject to substantial statistical heterogeneity, imprecision, or both, making it difficult to draw conclusions. Thirty-four studies investigated multicomponent interventions to improve smoking cessation rates. There was substantial variation in the combinations of strategies tested, and the resulting individual study effect estimates, precluding meta-analyses in most cases. Meta-analyses provided some evidence that adjunctive counseling combined with either cost-free medications or provider training enhanced quit rates when compared with standard care alone. However, analyses were limited by small numbers of events, high statistical heterogeneity, and studies at high risk of bias. Analyses looking at the effects of combining provider training with flow sheets to aid physician decision-making, and with outreach facilitation, found no clear evidence that these combinations increased quit rates; however, analyses were limited by imprecision, and there was some indication that these approaches did improve some forms of provider implementation.

AUTHORS' CONCLUSIONS

There is moderate-certainty evidence that providing adjunctive counseling by an allied health professional, cost-free smoking cessation medications, and tailored printed materials as part of smoking cessation support in primary care can increase the number of people who achieve smoking cessation. There is no clear evidence that providing participants with biomedical risk feedback, or primary care providers with training or incentives to provide smoking cessation support enhance quit rates. However, we rated this evidence as of low or very low certainty, and so conclusions are likely to change as further evidence becomes available. Most of the studies in this review evaluated smoking cessation interventions that had already been extensively tested in the general population. Further studies should assess strategies designed to optimize the delivery of those interventions already known to be effective within the primary care setting. Such studies should be cluster-randomized to account for the implications of implementation in this particular setting. Due to substantial variation between studies in this review, identifying optimal characteristics of multicomponent interventions to improve the delivery of smoking cessation treatment was challenging. Future research could use component network meta-analysis to investigate this further.

mHealth for Integrated People-Centred Health Services in the Western Pacific: A Systematic Review

OBJECTIVE

This review aimed to examine how mobile health (mHealth) to support integrated people-centred health services has been implemented and evaluated in the World Health Organization (WHO) Western Pacific Region (WPR).

METHODS

Eight scientific databases were searched. Two independent reviewers screened the literature in title and abstract stages, followed by full-text appraisal, data extraction, and synthesis of eligible studies. Studies were extracted to capture details of the mhealth tools used, the service issues addressed, the study design, and the outcomes evaluated. We then mapped the included studies using the 20 sub-strategies of the WHO Framework on Integrated People-Centred Health Services (IPCHS); as well as with the RE-AIM (Reach, effectiveness, adoption, implementation and maintenance) framework, to understand how studies implemented and evaluated interventions.

RESULTS

We identified 39 studies, predominantly from Australia (n = 16), China (n = 7), Malaysia (n = 4) and New Zealand (n = 4), and little from low income countries. The mHealth modalities included text messaging, voice and video communication, mobile applications and devices (point-of-care, GPS, and Bluetooth). Health issues addressed included: medication adherence, smoking cessation, cardiovascular disease, heart failure, asthma, diabetes, and lifestyle activities respectively. Almost all were community-based and focused on service issues; only half were disease-specific. mHealth facilitated integrated IPCHS by: enabling citizens and communities to bypass gatekeepers and directly access services; increasing affordability and accessibility of services; strengthening governance over the access, use, safety and quality of clinical care; enabling scheduling and navigation of services; transitioning patients and caregivers between care sectors; and enabling the evaluation of safety and quality outcomes for systemic improvement. Evaluations of mHealth interventions did not always report the underlying theories. They predominantly reported cognitive/behavioural changes rather than patient outcomes. The utility of mHealth to support and improve IPCHS was evident. However, IPCHS strategy 2 (participatory governance and accountability) was addressed least frequently. Implementation was evaluated in regard to reach (n = 30), effectiveness (n = 24); adoption (n = 5), implementation (n = 9), and maintenance (n = 1).

CONCLUSIONS

mHealth can transition disease-centred services towards people-centred services. Critical appraisal of studies highlighted methodological issues, raising doubts about validity. The limited evidence for large-scale implementation and international variation in reporting of mHealth practice, modalities used, and health domains addressed requires capacity building. Information-enhanced implementation and evaluation of IPCHS, particularly for participatory governance and accountability, is also important.

Telephone counselling for smoking cessation

BACKGROUND

Telephone services can provide information and support for smokers. Counselling may be provided proactively or offered reactively to callers to smoking cessation helplines.

OBJECTIVES

To evaluate the effect of telephone support to help smokers quit, including proactive or reactive counselling, or the provision of other information to smokers calling a helpline.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialised Register, clinicaltrials.gov, and the ICTRP for studies of telephone counselling, using search terms including 'hotlines' or 'quitline' or 'helpline'. Date of the most recent search: May 2018.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials which offered proactive or reactive telephone counselling to smokers to assist smoking cessation.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We pooled studies using a random-effects model and assessed statistical heterogeneity amongst subgroups of clinically comparable studies using the I2 statistic. In trials including smokers who did not call a quitline, we used meta-regression to investigate moderation of the effect of telephone counselling by the planned number of calls in the intervention, trial selection of participants that were motivated to quit, and the baseline support provided together with telephone counselling (either self-help only, brief face-to-face intervention, pharmacotherapy, or financial incentives).

MAIN RESULTS

We identified 104 trials including 111,653 participants that met the inclusion criteria. Participants were mostly adult smokers from the general population, but some studies included teenagers, pregnant women, and people with long-term or mental health conditions. Most trials (58.7%) were at high risk of bias, while 30.8% were at unclear risk, and only 11.5% were at low risk of bias for all domains assessed. Most studies (100/104) assessed proactive telephone counselling, as opposed to reactive forms.Among trials including smokers who contacted helplines (32,484 participants), quit rates were higher for smokers receiving multiple sessions of proactive counselling (risk ratio (RR) 1.38, 95% confidence interval (CI) 1.19 to 1.61; 14 trials, 32,484 participants; I2 = 72%) compared with a control condition providing self-help materials or brief counselling in a single call. Due to the substantial unexplained heterogeneity between studies, we downgraded the certainty of the evidence to moderate.In studies that recruited smokers who did not call a helpline, the provision of telephone counselling increased quit rates (RR 1.25, 95% CI 1.15 to 1.35; 65 trials, 41,233 participants; I2 = 52%). Due to the substantial unexplained heterogeneity between studies, we downgraded the certainty of the evidence to moderate. In subgroup analysis, we found no evidence that the effect of telephone counselling depended upon whether or not other interventions were provided (P = 0.21), no evidence that more intensive support was more effective than less intensive (P = 0.43), or that the effect of telephone support depended upon whether or not people were actively trying to quit smoking (P = 0.32). However, in meta-regression, telephone counselling was associated with greater effectiveness when provided as an adjunct to self-help written support (P < 0.01), or to a brief intervention from a health professional (P = 0.02); telephone counselling was less effective when provided as an adjunct to more intensive counselling. Further, telephone support was more effective for people who were motivated to try to quit smoking (P = 0.02). The findings from three additional trials of smokers who had not proactively called a helpline but were offered telephone counselling, found quit rates were higher in those offered three to five telephone calls compared to those offered just one call (RR 1.27, 95% CI 1.12 to 1.44; 2602 participants; I2 = 0%).

AUTHORS' CONCLUSIONS

There is moderate-certainty evidence that proactive telephone counselling aids smokers who seek help from quitlines, and moderate-certainty evidence that proactive telephone counselling increases quit rates in smokers in other settings. There is currently insufficient evidence to assess potential variations in effect from differences in the number of contacts, type or timing of telephone counselling, or when telephone counselling is provided as an adjunct to other smoking cessation therapies. Evidence was inconclusive on the effect of reactive telephone counselling, due to a limited number studies, which reflects the difficulty of studying this intervention.

Evidence from interventions based on theoretical models for lifestyle modification (physical activity, diet, alcohol and tobacco use) in primary care settings: A systematic review

OBJECTIVE

To determine the effectiveness of health promotion interventions based on theoretical models of behavioral change to modify the main lifestyle factors (physical activity, diet, alcohol and tobacco) in adults receiving primary health care (PHC).

METHODS

We searched the MEDLINE and Cochrane Database of Systematic Reviews from January 2000 to December 2012. Two reviewers independently performed the first screening of titles and abstracts, the methodological quality assessment using the lecturacritica.com tool, and the extraction of necessary data to systematize the available information.

RESULTS

Only few studies met the inclusion criteria (17 studies from 30 articles). Thirteen were randomized controlled trials, three systematic reviews, and one observational study. The transtheoretical model was the most frequent (13 studies), and obtained strong evidence of its effectiveness for dietary interventions in the short-term and for smoking cessation interventions in the long-term as compared to usual PHC practice. Limited evidence was found for smoking cessation interventions based in the social cognitive theory.

CONCLUSION

There are few studies that explicitly link intervention strategies and theories of behavioral change. A rigorous evaluation of the theoretical principles could help researchers and practitioners to understand how and why interventions succeed or fail.

Telephone counselling for smoking cessation

BACKGROUND

Telephone services can provide information and support for smokers. Counselling may be provided proactively or offered reactively to callers to smoking cessation helplines.

OBJECTIVES

To evaluate the effect of proactive and reactive telephone support via helplines and in other settings to help smokers quit.

SEARCH METHODS

We searched the Cochrane Tobacco Addiction Group Specialised Register for studies of telephone counselling, using search terms including 'hotlines' or 'quitline' or 'helpline'. Date of the most recent search: May 2013.

SELECTION CRITERIA

randomized or quasi-randomised controlled trials in which proactive or reactive telephone counselling to assist smoking cessation was offered to smokers or recent quitters.

DATA COLLECTION AND ANALYSIS

One author identified and data extracted trials, and a second author checked them. The main outcome measure was the risk ratio for abstinence from smoking after at least six months follow-up. We selected the strictest measure of abstinence, using biochemically validated rates where available. We considered participants lost to follow-up to be continuing smokers. Where trials had more than one arm with a less intensive intervention we used only the most similar intervention without the telephone component as the control group in the primary analysis. We assessed statistical heterogeneity amongst subgroups of clinically comparable studies using the I² statistic. We considered trials recruiting callers to quitlines separately from studies recruiting in other settings. Where appropriate, we pooled studies using a fixed-effect model. We used a meta-regression to investigate the effect of differences in planned number of calls, selection for motivation, and the nature of the control condition (self help only, minimal intervention, pharmacotherapy) in the group of studies recruiting in non-quitline settings.

MAIN RESULTS

Seventy-seven trials met the inclusion criteria. Some trials were judged to be at risk of bias in some domains but overall we did not judge the results to be at high risk of bias. Among smokers who contacted helplines, quit rates were higher for groups randomized to receive multiple sessions of proactive counselling (nine studies, > 24,000 participants, risk ratio (RR) for cessation at longest follow-up 1.37, 95% confidence interval (CI) 1.26 to 1.50). There was mixed evidence about whether increasing the number of calls altered quit rates but most trials used more than two calls. Three studies comparing different counselling approaches during a single quitline contact did not detect significant differences. Of three studies that tested the provision of access to a hotline two detected a significant benefit and one did not.Telephone counselling not initiated by calls to helplines also increased quitting (51 studies, > 30,000 participants, RR 1.27; 95% CI 1.20 to 1.36). In a meta-regression controlling for other factors the effect was estimated to be slightly larger if more calls were offered, and in trials that specifically recruited smokers motivated to try to quit. The relative extra benefit of counselling was smaller when it was provided in addition to pharmacotherapy (usually nicotine replacement therapy) than when the control group only received self-help material or a brief intervention.A further eight studies were too diverse to contribute to meta-analyses and are discussed separately. Two compared different intensities of counselling, both of which detected a dose response; one of these detected a benefit of multiple counselling sessions over a single call for people prescribed bupropion. The others tested a variety of interventions largely involving offering telephone counselling as part of a referral or systems change and none detected evidence of effect.

AUTHORS' CONCLUSIONS

Proactive telephone counselling aids smokers who seek help from quitlines. Telephone quitlines provide an important route of access to support for smokers, and call-back counselling enhances their usefulness. There is limited evidence about the optimal number of calls. Proactive telephone counselling also helps people who receive it in other settings. There is some evidence of a dose response; one or two brief calls are less likely to provide a measurable benefit. Three or more calls increase the chances of quitting compared to a minimal intervention such as providing standard self-help materials, or brief advice, or compared to pharmacotherapy alone.

Effectiveness of telephone-based follow-up support delivered in combination with a multi-component smoking cessation intervention in family practice: a cluster-randomized trial

OBJECTIVE

To determine whether telephone-based smoking cessation follow-up counseling (FC), when delivered as part of a multi-component intervention program is associated with increased rates of follow-up support and smoking abstinence.

METHODS

A cluster randomized controlled-trial was conducted within family medicine practices in Ontario, Canada. Consecutive adult patients who smoked were enrolled at two time points, the baseline period (2009) and the post-intervention period (2009-2011). Smoking abstinence was determined by telephone interview 4 months following enrollment. Both groups implemented a multi-component intervention program. Practices randomized to the FC group could also refer patients to a follow-up support program which involved 5 telephone contacts over a 2-month period.

RESULTS

Eight practices, 130 providers, and 928 eligible patients participated in the study. No statistically significant difference in 7-day point-prevalence abstinence was observed between intervention groups. There was a significant increase in referral to follow-up in both intervention groups. Significantly higher rates of smoking abstinence [25.7% vs. 11.3%; adjusted OR 3.1 (95% CI: 1.1, 8.6), p<0.05] were documented among the twenty-nine percent of FC participants who were referred to the follow-up support program compared to the MC group.

CONCLUSION

Access to external follow-up support did not increase rates at which follow-up support was delivered.

Feasibility, acceptability and impact of a telephone support service initiated in primary medical care to help Arabic smokers quit

Evidence-based tobacco control in ethnic minorities is compromised by the near absence of rigorous testing of interventions in either prevention or cessation. This randomised controlled trial was designed to evaluate the feasibility, acceptability and impact of a culturally specific cessation intervention delivered in the context of primary medical care in the most culturally diverse region of New South Wales. Adult Arabic smokers were recruited from practices of 29 general practitioners (GPs) in south-west Sydney and randomly allocated to usual care (n = 194) or referred to six sessions of smoking cessation telephone support delivered by bilingual psychologists (n = 213). Although 62.2% of participants indicated that telephone support would benefit Arabic smokers, there were no significant differences at 6 or 12 months between intervention and control groups in point prevalence abstinence rates (11.7% vs 12.9%, P = 0.83; 8.4% vs 11.3%, P = 0.68, respectively) or the mean shift in stage-of-change towards intention to quit. As participants and GPs found telephone support acceptable, we also discuss redesign and the unfulfilled obligation to expand the evidence base in tobacco control from which the ethnic majority already benefits.

Stage-based interventions for smoking cessation

BACKGROUND

The transtheoretical model is the most widely known of several stage-based theories of behaviour. It proposes that smokers move through a discrete series of motivational stages before they quit successfully. These are precontemplation (no thoughts of quitting), contemplation (thinking about quitting), preparation (planning to quit in the next 30 days), action (quitting successfully for up to six months), and maintenance (no smoking for more than six months). According to this influential model, interventions which help people to stop smoking should be tailored to their stage of readiness to quit, and are designed to move them forward through subsequent stages to eventual success. People in the preparation and action stages of quitting would require different types of support from those in precontemplation or contemplation.

OBJECTIVES

Our primary objective was to test the effectiveness of stage-based interventions in helping smokers to quit.

SEARCH STRATEGY

We searched the Cochrane Tobacco Addiction Group's specialised register for trials, using the terms ('stage* of change', 'transtheoretical model*', 'trans-theoretical model*, 'precaution adoption model*', 'health action model', 'processes of change questionnaire*', 'readiness to change', 'tailor*') and 'smoking' in the title or abstract, or as keywords. The latest search was in August 2010.

SELECTION CRITERIA

We included randomized controlled trials, which compared stage-based interventions with non-stage-based controls, with 'usual care' or with assessment only. We excluded trials which did not report a minimum follow-up period of six months from start of treatment, and those which measured stage of change but did not modify their intervention in the light of it.

DATA COLLECTION AND ANALYSIS

We extracted data in duplicate on the participants, the dose and duration of intervention, the outcome measures, the randomization procedure, concealment of allocation, and completeness of follow up.The main outcome was abstinence from smoking for at least six months. We used the most rigorous definition of abstinence, and preferred biochemically validated rates where reported. Where appropriate we performed meta-analysis to estimate a pooled risk ratio, using the Mantel-Haenszel fixed-effect model.

MAIN RESULTS

We found 41 trials (>33,000 participants) which met our inclusion criteria. Four trials, which directly compared the same intervention in stage-based and standard versions, found no clear advantage for the staging component. Stage-based versus standard self-help materials (two trials) gave a relative risk (RR) of 0.93 (95% CI 0.62 to 1.39). Stage-based versus standard counselling (two trials) gave a relative risk of 1.00 (95% CI 0.82 to 1.22). Six trials of stage-based self-help systems versus any standard self-help support demonstrated a benefit for the staged groups, with an RR of 1.27 (95% CI 1.01 to 1.59). Twelve trials comparing stage-based self help with 'usual care' or assessment-only gave an RR of 1.32 (95% CI 1.17 to 1.48). Thirteen trials of stage-based individual counselling versus any control condition gave an RR of 1.24 (95% CI 1.08 to 1.42). These findings are consistent with the proven effectiveness of these interventions in their non-stage-based versions. The evidence was unclear for telephone counselling, interactive computer programmes or training of doctors or lay supporters. This uncertainty may be due in part to smaller numbers of trials.

AUTHORS' CONCLUSIONS

Based on four trials using direct comparisons, stage-based self-help interventions (expert systems and/or tailored materials) and individual counselling were neither more nor less effective than their non-stage-based equivalents. Thirty-one trials of stage-based self help or counselling interventions versus any control condition demonstrated levels of effectiveness which were comparable with their non-stage-based counterparts. Providing these forms of practical support to those trying to quit appears to be more productive than not intervening. However, the additional value of adapting the intervention to the smoker's stage of change is uncertain. The evidence is not clear for other types of staged intervention, including telephone counselling, interactive computer programmes and training of physicians or lay supporters. The evidence does not support the restriction of quitting advice and encouragement only to those smokers perceived to be in the preparation and action stages.

Strategies to increase the delivery of smoking cessation treatments in primary care settings: a systematic review and meta-analysis

OBJECTIVES

A systematic review and meta-analysis was conducted to evaluate evidence-based strategies for increasing the delivery of smoking cessation treatments in primary care clinics.

METHODS

The review included studies published before January 1, 2009. The pooled odds-ratio (OR) was calculated for intervention group versus control group for practitioner performance for "5As" (Ask, Advise, Assess, Assist and Arrange) delivery and smoking abstinence. Multi-component interventions were defined as interventions which combined two or more intervention strategies.

RESULTS

Thirty-seven trials met eligibility criteria. Evidence from multiple large-scale trials was found to support the efficacy of multi-component interventions in increasing "5As" delivery. The pooled OR for multi-component interventions compared to control was 1.79 [95% CI 1.6-2.1] for "ask", 1.6 [95% CI 1.4-1.8] for "advice", 9.3 [95% CI 6.8-12.8] for "assist" (quit date) and 3.5 [95% CI 2.8-4.2] for "assist" (prescribe medications). Evidence was also found to support the value of practice-level interventions in increasing 5As delivery. Adjunct counseling [OR 1.7; 95% CI 1.5-2.0] and multi-component interventions [OR 2.2; 95% CI 1.7-2.8] were found to significantly increase smoking abstinence.

CONCLUSION

Multi-component interventions improve smoking outcomes in primary care settings. Future trials should attempt to isolate which components of multi-component interventions are required to optimize cost-effectiveness.

Telephone counselling for smoking cessation

BACKGROUND

Telephone services can provide information and support for smokers. Counselling may be provided proactively or offered reactively to callers to smoking cessation helplines.

OBJECTIVES

To evaluate the effect of proactive and reactive telephone support to help smokers quit.

SEARCH STRATEGY

We searched the Cochrane Tobacco Addiction Group trials register for studies using free text term 'telephone*' or the keywords 'telephone counselling' or 'Hotlines' or 'Telephone' . Date of the most recent search: January 2006.

SELECTION CRITERIA

Randomized or quasi-randomized controlled trials in which proactive or reactive telephone counselling to assist smoking cessation was offered to smokers or recent quitters.

DATA COLLECTION AND ANALYSIS

Trials were identified and data extracted by one person (LS) and checked by a second (TL). The main outcome measure was the odds ratio for abstinence from smoking after at least six months follow up. We selected the strictest measure of abstinence, using biochemically validated rates where available. We considered participants lost to follow-up to be continuing smokers. Where trials had more than one arm with a less intensive intervention we used only the most similar intervention without the telephone component as the control group in the primary analysis. We assessed statistical heterogeneity amongst sub groups of clinically comparable studies using the I(2) statistic. Where appropriate, we pooled studies using a fixed-effect model. A meta-regression was used to investigate the effect of differences in planned number of calls.

MAIN RESULTS

Forty-eight trials met the inclusion criteria. Among smokers who contacted helplines, quit rates were higher for groups randomised to receive multiple sessions of call-back counselling (eight studies, >18,000 participants, odds ratio (OR) for long term cessation 1.41, 95% confidence interval (CI) 1.27 to 1.57). Two of these studies showed a significant benefit of more intensive compared to less intensive intervention. Telephone counselling not initiated by calls to helplines also increased quitting (29 studies, >17,000 participants, OR 1.33, 95% CI 1.21 to 1.47). A meta-regression detected a significant association between the maximum number of planned calls and the effect size. There was clearer evidence of benefit in the subgroup of trials recruiting smokers motivated to quit. Of two studies that provided access to a hotline one showed a significant benefit and one did not. Two studies comparing different counselling approaches during a single session did not detect significant differences. A further seven studies were too diverse to contribute to meta-analyses and are discussed separately.

AUTHORS' CONCLUSIONS

Proactive telephone counselling helps smokers interested in quitting. There is evidence of a dose response; one or two brief calls are less likely to provide a measurable benefit. Three or more calls increases the odds of quitting compared to a minimal intervention such as providing standard self-help materials, brief advice, or compared to pharmacotherapy alone. Telephone quitlines provide an important route of access to support for smokers, and call-back counselling enhances their usefulness.