BACKGROUND AND AIMS: Behavioural smoking cessation trials have employed comparators that vary considerably between trials. Although some previous meta-analyses made attempts to account for variability in comparators, these relied on subsets of trials and incomplete data on comparators. This study aimed to estimate the relative effectiveness of (individual) smoking cessation interventions, while accounting for variability in comparators using comprehensive data on experimental and comparator interventions.
METHODS: Systematic review and meta-regression including 172 randomised controlled trials with at least 6 months' follow-up and biochemically verified smoking cessation. Authors were contacted to obtain unpublished information. This information was coded in terms of active content and attributes of the study population and methods. Meta-regression was used to create a model predicting smoking cessation outcomes. This model was used to re-estimate intervention effects, as if all interventions have been evaluated against the same comparators. Outcome measures included log odds of smoking cessation for the meta-regression models and smoking cessation differences and ratios to compare relative effectiveness.
RESULTS: The meta-regression model predicted smoking cessation rates well (pseudo R2 =.44). Standardizing the comparator had substantial impact on conclusions regarding the (relative) effectiveness of trials and types of intervention. Compared with a 'no support comparator', self-help was 1.33 times (95% confidence interval [CI]=1.16-1.49), brief physician advice 1.61 times (95%CI=1.31-1.90) nurse individual counselling 1.76 times (95%CI=1.62-1.90), psychologist individual counselling 2.04 times (95%CI=1.95-2.15), and individual group psychologist interventions 2.06 times (95%CI=1.92-2.20) more effective. Notably, more elaborate experimental interventions (e.g., psychologist counselling) were typically compared with more elaborate comparators, masking their effectiveness.
CONCLUSIONS: Comparator variability and underreporting of comparators obscures the interpretation, comparison and generalisability of behavioural smoking cessation trials. Comparator variability should thus be taken into account when interpreting and synthesising evidence from trials. Otherwise, policy makers, practitioners and researchers may draw incorrect conclusions about the (cost)effectiveness of smoking cessation interventions and their constituent components.
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.
BACKGROUND: Tobacco smoking is the leading preventable cause of death worldwide, which makes it essential to stimulate smoking cessation. The financial cost of smoking cessation treatment can act as a barrier to those seeking support. We hypothesised that provision of financial assistance for people trying to quit smoking, or reimbursement of their care providers, could lead to an increased rate of successful quit attempts. This is an update of the original 2005 review.
OBJECTIVES: The primary objective of this review was to assess the impact of reducing the costs for tobacco smokers or healthcare providers for using or providing smoking cessation treatment through healthcare financing interventions on abstinence from smoking. The secondary objectives were to examine the effects of different levels of financial support on the use or prescription of smoking cessation treatment, or both, and on the number of smokers making a quit attempt (quitting smoking for at least 24 hours). We also assessed the cost effectiveness of different financial interventions, and analysed the costs per additional quitter, or per quality-adjusted life year (QALY) gained.
SEARCH METHODS: We searched the Cochrane Tobacco Addiction Group Specialised Register in September 2016.
SELECTION CRITERIA: We considered randomised controlled trials (RCTs), controlled trials and interrupted time series studies involving financial benefit interventions to smokers or their healthcare providers, or both.
DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data and assessed the quality of the included studies. We calculated risk ratios (RR) for individual studies on an intention-to-treat basis and performed meta-analysis using a random-effects model.
MAIN RESULTS: In the current update, we have added six new relevant studies, resulting in a total of 17 studies included in this review involving financial interventions directed at smokers or healthcare providers, or both.Full financial interventions directed at smokers had a favourable effect on abstinence at six months or longer when compared to no intervention (RR 1.77, 95% CI 1.37 to 2.28, I² = 33%, 9333 participants). There was no evidence that full coverage interventions increased smoking abstinence compared to partial coverage interventions (RR 1.02, 95% CI 0.71 to 1.48, I² = 64%, 5914 participants), but partial coverage interventions were more effective in increasing abstinence than no intervention (RR 1.27 95% CI 1.02 to 1.59, I² = 21%, 7108 participants). The economic evaluation showed costs per additional quitter ranging from USD 97 to USD 7646 for the comparison of full coverage with partial or no coverage.There was no clear evidence of an effect on smoking cessation when we pooled two trials of financial incentives directed at healthcare providers (RR 1.16, CI 0.98 to 1.37, I² = 0%, 2311 participants).Full financial interventions increased the number of participants making a quit attempt when compared to no interventions (RR 1.11, 95% CI 1.04 to 1.17, I² = 15%, 9065 participants). There was insufficient evidence to show whether partial financial interventions increased quit attempts compared to no interventions (RR 1.13, 95% CI 0.98 to 1.31, I² = 88%, 6944 participants).Full financial interventions increased the use of smoking cessation treatment compared to no interventions with regard to various pharmacological and behavioural treatments: nicotine replacement therapy (NRT): RR 1.79, 95% CI 1.54 to 2.09, I² = 35%, 9455 participants; bupropion: RR 3.22, 95% CI 1.41 to 7.34, I² = 71%, 6321 participants; behavioural therapy: RR 1.77, 95% CI 1.19 to 2.65, I² = 75%, 9215 participants.There was evidence that partial coverage compared to no coverage reported a small positive effect on the use of bupropion (RR 1.15, 95% CI 1.03 to 1.29, I² = 0%, 6765 participants). Interventions directed at healthcare providers increased the use of behavioural therapy (RR 1.69, 95% CI 1.01 to 2.86, I² = 85%, 25820 participants), but not the use of NRT and/or bupropion (RR 0.94, 95% CI 0.76 to 1.18, I² = 6%, 2311 participants).We assessed the quality of the evidence for the main outcome, abstinence from smoking, as moderate. In most studies participants were not blinded to the different study arms and researchers were not blinded to the allocated interventions. Furthermore, there was not always sufficient information on attrition rates. We detected some imprecision but we judged this to be of minor consequence on the outcomes of this study.
AUTHORS' CONCLUSIONS: Full financial interventions directed at smokers when compared to no financial interventions increase the proportion of smokers who attempt to quit, use smoking cessation treatments, and succeed in quitting. There was no clear and consistent evidence of an effect on smoking cessation from financial incentives directed at healthcare providers. We are only moderately confident in the effect estimate because there was some risk of bias due to a lack of blinding in participants and researchers, and insufficient information on attrition rates.
Background: Outpatient care facilities provide a variety of basic healthcare services to individuals who do not require hospitalisation or institutionalisation, and are usually the patient's first contact. The provision of outpatient care contributes to immediate and large gains in health status, and a large portion of total health expenditure goes to outpatient healthcare services. Payment method is one of the most important incentive methods applied by purchasers to guide the performance of outpatient care providers. Objectives: To assess the impact of different payment methods on the performance of outpatient care facilities and to analyse the differences in impact of payment methods in different settings. Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), 2016, Issue 3, part of the Cochrane Library (searched 8 March 2016); MEDLINE, OvidSP (searched 8 March 2016); Embase, OvidSP (searched 24 April 2014); PubMed (NCBI) (searched 8 March 2016); Dissertations and Theses Database, ProQuest (searched 8 March 2016); Conference Proceedings Citation Index (ISI Web of Science) (searched 8 March 2016); IDEAS (searched 8 March 2016); EconLit, ProQuest (searched 8 March 2016); POPLINE, K4Health (searched 8 March 2016); China National Knowledge Infrastructure (searched 8 March 2016); Chinese Medicine Premier (searched 8 March 2016); OpenGrey (searched 8 March 2016); ClinicalTrials.gov, US National Institutes of Health (NIH) (searched 8 March 2016); World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (searched 8 March 2016); and the website of the World Bank (searched 8 March 2016). In addition, we searched the reference lists of included studies and carried out a citation search for the included studies via ISI Web of Science to find other potentially relevant studies. We also contacted authors of the main included studies regarding any further published or unpublished work. Selection criteria: Randomised trials, non-randomised trials, controlled before-after studies, interrupted time series, and repeated measures studies that compared different payment methods for outpatient health facilities. We defined outpatient care facilities in this review as facilities that provide health services to individuals who do not require hospitalisation or institutionalisation. We only included methods used to transfer funds from the purchaser of healthcare services to health facilities (including groups of individual professionals). These include global budgets, line-item budgets, capitation, fee-for-service (fixed and unconstrained), pay for performance, and mixed payment. The primary outcomes were service provision outcomes, patient outcomes, healthcare provider outcomes, costs for providers, and any adverse effects. Data collection and analysis: At least two review authors independently extracted data and assessed the risk of bias. We conducted a structured synthesis. We first categorised the comparisons and outcomes and then described the effects of different types of payment methods on different categories of outcomes. We used a fixed-effect model for meta-analysis within a study if a study included more than one indicator in the same category of outcomes. We used a random-effects model for meta-analysis across studies. If the data for meta-analysis were not available in some studies, we calculated the median and interquartile range. We reported the risk ratio (RR) for dichotomous outcomes and the relative change for continuous outcomes. Main results: We included 21 studies from Afghanistan, Burundi, China, Democratic Republic of Congo, Rwanda, Tanzania, the United Kingdom, and the United States of health facilities providing primary health care and mental health care. There were three kinds of payment comparisons. 1) Pay for performance (P4P) combined with some existing payment method (capitation or different kinds of input-based payment) compared to the existing payment method We included 18 studies in this comparison, however we did not include five studies in the effects analysis due to high risk of bias. From the 13 studies, we found that the extra P4P incentives probably slightly improved the health professionals' use of some tests and treatments (adjusted RR median = 1.095, range 1.01 to 1.17; moderate-certainty evidence), and probably led to little or no difference in adherence to quality assurance criteria (adjusted percentage change median = -1.345%, range -8.49% to 5.8%; moderate-certainty evidence). We also found that P4P incentives may have led to little or no difference in patients' utilisation of health services (adjusted RR median = 1.01, range 0.96 to 1.15; low-certainty evidence) and may have led to little or no difference in the control of blood pressure or cholesterol (adjusted RR = 1.01, range 0.98 to 1.04; low-certainty evidence). 2) Capitation combined with P4P compared to fee-for-service (FFS) One study found that compared with FFS, a capitated budget combined with payment based on providers' performance on antibiotic prescriptions and patient satisfaction probably slightly reduced antibiotic prescriptions in primary health facilities (adjusted RR 0.84, 95% confidence interval 0.74 to 0.96; moderate-certainty evidence). 3) Capitation compared to FFS Two studies compared capitation to FFS in mental health centres in the United States. Based on these studies, the effects of capitation compared to FFS on the utilisation and costs of services were uncertain (very low-certainty evidence). Authors' conclusions: Our review found that if policymakers intend to apply P4P incentives to pay health facilities providing outpatient services, this intervention will probably lead to a slight improvement in health professionals' use of tests or treatments, particularly for chronic diseases. However, it may lead to little or no improvement in patients' utilisation of health services or health outcomes. When considering using P4P to improve the performance of health facilities, policymakers should carefully consider each component of their P4P design, including the choice of performance measures, the performance target, payment frequency, if there will be additional funding, whether the payment level is sufficient to change the behaviours of health providers, and whether the payment to facilities will be allocated to individual professionals. Unfortunately, the studies included in this review did not help to inform those considerations. Well-designed comparisons of different payment methods for outpatient health facilities in low- and middle-income countries and studies directly comparing different designs (e.g. different payment levels) of the same payment method (e.g. P4P or FFS) are needed.
BACKGROUND AND OBJECTIVES: Pay-for-performance is a financial incentive which links physicians' income to the quality of their services. Although pay-for-performance is suggested to be an effective payment method in many pilot countries (ie the UK) and enjoys a wide application in primary health care, researches on it are yet to reach an agreement. Thus, a systematic review was conducted on the evidence of impact of pay-for-performance on behavior of primary care physicians and patient outcomes aiming to provide a comprehensive and objective evaluation of pay-for-performance for decision-makers.
METHODS: Studies were identified by searching PubMed, EMbase, and The Cochrane Library. Electronic search was conducted in the fourth week of January 2013. As the included studies had significant clinical heterogeneity, a descriptive analysis was conducted. Quality Index was adopted for quality assessment of evidences.
RESULTS: Database searches yielded 651 candidate articles, of which 44 studies fulfilled the inclusion criteria. An overall positive effect was found on the management of disease, which varied in accordance with the baseline medical quality and the practice size. Meanwhile, it could bring about new problems regarding the inequity, patients' dissatisfaction and increasing medical cost.
CONCLUSIONS: Decision-makers should consider the baseline conditions of medical quality and the practice size before new medical policies are enacted. Furthermore, most studies are retrospective and observational with high level of heterogeneity though, the descriptive analysis is still of significance.
OBJECTIVE: The objective of the present review is to evaluate multicomponent/complex primary care (PC) interventions for their effectiveness in continuous smoking abstinence by adult smokers.
DESIGN: A systematic review of randomised and non-randomised controlled trials was undertaken.
ELIGIBILITY CRITERIA FOR INCLUDED STUDIES: Selected studies met the following criteria: evaluated effects of a multicomponent/complex intervention (with 2 or more intervention components) in achieving at least 6-month abstinence in adult smokers who visited a PC, biochemical confirmation of abstinence, intention-to-treat analysis and results published in English/Spanish.
METHODS: We followed PRISMA statement to report the review. We searched the following data sources: MEDLINE, Web of Science, Scopus (from inception to February 2014), 3 key journals and a tobacco research bulletin. The Scottish Intercollegiate Guidelines Network checklists were used to evaluate methodological quality. Data selection, evaluation and extraction were done independently, using a paired review approach. Owing to the heterogeneity of interventions in the studies included, a meta-analysis was not conducted.
RESULTS: Of 1147 references identified, 9 studies were selected (10 204 participants, up to 48 months of follow-up, acceptable methodological quality). Methodologies used were mainly individual or group sessions, telephone conversations, brochures or quit-smoking kits, medications and economic incentives for doctors and no-cost medications for smokers. Complex interventions achieved long-term continuous abstinence ranging from 7% to 40%. Behavioural interventions were effective and had a dose-response effect. Both nicotine replacement and bupropion therapy were safe and effective, with no observed differences.
CONCLUSIONS: Multicomponent/complex interventions in PC are effective and safe, appearing to achieve greater long-term continuous smoking cessation than usual care and counselling alone. Selected studies were heterogeneous and some had significant losses to follow-up. Our results show that smoking interventions should include more than one component and a strong follow-up of the patient to maximise results.
BACKGROUND: Family medicine is undergoing reforms in several countries. In order to attain the health care objectives such as quality, efficiency and accessibility, different tools are being utilized including legislation, organizational models and financial incentives. The purpose of this literature review is to discuss the impact of different methods of payment to family physicians and general practitioners, quantity of service provision and referral rate behavior. METHODS: We carried out a systematic literature search in five electronic databases including PubMed, Science Direct, Emerald, Wiley Inter Science, Springer Link and ANNFAMMED published to September 2011. We also reviewed the references of the final selected articles to identify the relevant articles. Search strategy included the following combination of keywords: “payment”, “reimbursement”, “compensation method”, “general practitioner” and “service provision”. From 2738 articles that were identified in our first search, eleven articles were included in the final review. We extracted data from the selected articles and performed content analyses in regards to the type of intervention. RESULTS: In comparison to salary and capitation, fee-for-service (FFS) was associated with 9%-12% lower referral rate presumably because physicians wanted to treat patients and increase their incomes by producing more services. Compared with FFS, capitation payment decreased the number of provided services (14% lower visits in the outpatient settings and 50%-60% lower visits in the inpatient settings) due to budget limitations. We found that referral rate to hospitals and specialists increased up to 20% in capitation. CONCLUSION: This literature review shows that each payment method for family physicians and health professionals creates a particular set of incentives for physician. While nations act differently and in line with their health system goals and context, international experience suggests some guidance for policy makers. New policies should ensure a payment system that is optimal for local health care delivery structure and compliant with local laws, regulations, and tax system.
OBJECTIVE: Financial incentives are seen as one approach to encourage more systematic use of smoking cessation interventions by healthcare professionals. A systematic review was conducted to examine the evidence for this.
METHODS: Medline, Embase, PsychINFO, Cochrane Library, ISI Web of Science and sources of grey literature were used as data sources. Studies were included if they reported the effects of any financial incentive provided to healthcare professionals to undertake smoking cessation-related activities. Data extraction and quality assessment for each study were conducted by one reviewer and checked by a second. A total of 18 studies were identified, consisting of 3 randomised controlled trials and 15 observational studies. All scored in the mid range for quality. In all, 8 studies examined smoking cessation activities alone and 10 studied the UK's Quality and Outcomes Framework targeting quality measures for chronic disease management including smoking recording or cessation activities. Five non-Quality and Outcomes Framework studies examined the effects of financial incentives on individual doctors and three examined effects on groups of healthcare professionals based in clinics and general practices. Most studies showed improvements in recording smoking status and smoking cessation advice. Five studies examined the impact of financial incentives on quit rates and longer-term abstinence and these showed mixed results.
CONCLUSIONS: Financial incentives appear to improve recording of smoking status, and increase the provision of cessation advice and referrals to stop smoking services. Currently there is not sufficient evidence to show that financial incentives lead to reductions in smoking rates.
BACKGROUND: Pay-for-performance (P4P) intents to stimulate both more effective and more efficient health care delivery. To date, evidence on whether P4P itself is an efficient method has not been systematically analyzed.
OBJECTIVE: To identify and analyze the existing literature regarding economic evaluation of P4P.
DATA SOURCES: English, German, Spanish, and Turkish language literature were searched in the following databases: Business Source Complete, the Cochrane Library, Econlit, ISI web of knowledge, Medline (via PubMed), and PsycInfo (January 2000-April 2010).
STUDY SELECTION: Articles published in peer-reviewed journals and describing economic evaluations of P4P initiatives. Full economic evaluations, considering costs and consequences of the P4P intervention simultaneously, were the prime focus. Additionally, comparative partial evaluations were included if costs were described and the study allows for an assessment of consequences. Both experimental and observational studies were considered.
RESULTS: In total, nine studies could be identified. Three studies could be regarded as full economic evaluations, and six studies were classified as partial economic evaluations. Based on the full economic evaluations, P4P efficiency could not be demonstrated. Partial economic evaluations showed mixed results, but several flaws limit their significance. Ranges of costs and consequences were typically narrow, and programs differed considerably in design. Methodological quality assessment showed scores between 32% and 65%.
CONCLUSION: The results show that evidence on the efficiency of P4P is scarce and inconclusive. P4P efficiency could not be demonstrated. The small number and variability of included studies limit the strength of our conclusions. More research addressing P4P efficiency is needed.
BACKGROUND: Pay-for-performance (P4P) is increasingly touted as a means to improve health care quality.
PURPOSE: To evaluate the effect of P4P remuneration targeting individual health care providers.
DATA SOURCES: MEDLINE, EMBASE, Cochrane Library, OpenSIGLE, Canadian Evaluation Society Unpublished Literature Bank, New York Academy of Medicine Library Grey Literature Collection, and reference lists were searched up until June 2012.
STUDY SELECTION: Two reviewers independently identified original research papers (randomized, controlled trials; interrupted time series; uncontrolled and controlled before-after studies; and cohort comparisons).
DATA EXTRACTION: Two reviewers independently extracted the data.
DATA SYNTHESIS: The literature search identified 4 randomized, controlled trials; 5 interrupted time series; 3 controlled before-after studies; 1 nonrandomized, controlled study; 15 uncontrolled before-after studies; and 2 uncontrolled cohort studies. The variation in study quality, target conditions, and reported outcomes precluded meta-analysis. Uncontrolled studies (15 before-after studies, 2 cohort comparisons) suggested that P4P improves quality of care, but higher-quality studies with contemporaneous controls failed to confirm these findings. Two of the 4 randomized trials were negative, and the 2 statistically significant trials reported small incremental improvements in vaccination rates over usual care (absolute differences, 8.4 and 7.8 percentage points). Of the 5 interrupted time series, 2 did not detect any improvements in processes of care or clinical outcomes after P4P implementation, 1 reported initial statistically significant improvements in guideline adherence that dissipated over time, and 2 reported statistically significant improvements in blood pressure control in patients with diabetes balanced against statistically significant declines in hemoglobin A1c control.
LIMITATION: Few methodologically robust studies compare P4P with other payment models for individual practitioners; most are small observational studies of variable quality.
CONCLUSION: The effect of P4P targeting individual practitioners on quality of care and outcomes remains largely uncertain. Implementation of P4P models should be accompanied by robust evaluation plans.
PRIMARY FUNDING SOURCE: None.
Behavioural smoking cessation trials have employed comparators that vary considerably between trials. Although some previous meta-analyses made attempts to account for variability in comparators, these relied on subsets of trials and incomplete data on comparators. This study aimed to estimate the relative effectiveness of (individual) smoking cessation interventions, while accounting for variability in comparators using comprehensive data on experimental and comparator interventions.
METHODS:
Systematic review and meta-regression including 172 randomised controlled trials with at least 6 months' follow-up and biochemically verified smoking cessation. Authors were contacted to obtain unpublished information. This information was coded in terms of active content and attributes of the study population and methods. Meta-regression was used to create a model predicting smoking cessation outcomes. This model was used to re-estimate intervention effects, as if all interventions have been evaluated against the same comparators. Outcome measures included log odds of smoking cessation for the meta-regression models and smoking cessation differences and ratios to compare relative effectiveness.
RESULTS:
The meta-regression model predicted smoking cessation rates well (pseudo R2 =.44). Standardizing the comparator had substantial impact on conclusions regarding the (relative) effectiveness of trials and types of intervention. Compared with a 'no support comparator', self-help was 1.33 times (95% confidence interval [CI]=1.16-1.49), brief physician advice 1.61 times (95%CI=1.31-1.90) nurse individual counselling 1.76 times (95%CI=1.62-1.90), psychologist individual counselling 2.04 times (95%CI=1.95-2.15), and individual group psychologist interventions 2.06 times (95%CI=1.92-2.20) more effective. Notably, more elaborate experimental interventions (e.g., psychologist counselling) were typically compared with more elaborate comparators, masking their effectiveness.
CONCLUSIONS:
Comparator variability and underreporting of comparators obscures the interpretation, comparison and generalisability of behavioural smoking cessation trials. Comparator variability should thus be taken into account when interpreting and synthesising evidence from trials. Otherwise, policy makers, practitioners and researchers may draw incorrect conclusions about the (cost)effectiveness of smoking cessation interventions and their constituent components.
Systematic Review Question»Systematic review of interventions
