Abstract
Introduction
Numerous guidelines have been developed worldwide to support healthcare professionals in providing evidence-based interventions to help individuals quit smoking and other forms of tobacco use. The evaluation of the quality of the guidelines of tobacco cessation is however deficient and lacking.
Methodology
PubMed, Embase, Scopus and Cochrane Databases were electronically searched. Additional search was carried out in National Institute for Health Care Excellence, Guidelines International Network, Google Scholar and references of relevant articles to screen studies relevant to this review. Guidelines on both health and allied health professionals in English language were included. The assessment of the guidelines in this review was carried out using the AGREE II instrument by four appraisers.
Results
Twenty guidelines were included in this review. A comparative evaluation of all the guidelines revealed consistently higher scores in clarity of presentation domain (74.4 ± 20.9) followed by scope and purpose (65.23 ± 17.19), stakeholder involvement (63.84 ± 18.29) and rigour of development domain (61.76 ± 20.24). Lower scores were reported in Applicability (59.18 ± 18.02) and least in Editorial Independence domain (58.29 ± 19.36).
Conclusion
Further guidelines developed should address the gaps identified in this review and be both evidence-based and feasible to implement in diverse clinical contexts.
Introduction
Tobacco use remains one of the most significant public health challenges globally, responsible for over 8 million deaths annually and a wide array of chronic diseases, including lung cancer, cardiovascular disease, and respiratory disorders. 1 Despite ongoing public health efforts to curb tobacco consumption, it continues to be a leading cause of preventable morbidity and mortality. Tobacco cessation is a critical intervention in reducing the global burden of tobacco-related diseases. Encouraging cessation can prevent the onset or progress of non- communicable diseases (NCD) and reduce mortality. 2
Numerous guidelines have been developed worldwide to support healthcare professionals in providing evidence-based interventions to help individuals quit smoking and other forms of tobacco use.3-22 However, the efficacy of the guidelines is dependent on their quality—the rigor of their evidence base, and their ability to be implemented effectively in clinical practice.
Guidelines on tobacco cessation often draw from diverse sources of evidence, and are aimed to provide healthcare professionals with clear, concise, and practical recommendations for treating tobacco dependence. However, despite the widespread availability of such guidelines, questions remain regarding their methodological quality, consistency, and applicability across different healthcare settings.
The quality of these guidelines is critical in ensuring their effectiveness in promoting tobacco cessation. Suboptimal guideline development processes, lack of transparency in evidence appraisal, and inconsistent recommendations can undermine their utility and hinder the widespread adoption of effective cessation strategies. No such research in the past has been carried out and the evaluation of the quality of the guidelines of tobacco cessation is deficient and lacking.
This study was thus aimed at assessing the quality of current guidelines on tobacco cessation. This systematic review will aid in identifying the strengths and weaknesses of the existing guidelines and is expected to provide insights into the current state of tobacco cessation guidelines. The findings from this study are intended to highlight areas where improvements in guidelines can be made to enhance their utility for clinicians and health policymakers.
Methodology
This review was undertaken to assess the quality of guidelines focusing on tobacco cessation. The critical evaluation of the guidelines was carried out by AGREE II instrument. 23 This systematic review was carried out in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered in PROSPERO [CRD42024537815].
Eligibility Criteria
To provide an assessment of up-to-date guidelines, only those released within the last 10 years on tobacco cessation were included in this review. Guidelines for both health and allied health professionals in English language were included. The most recent guideline was included if more than one has been released by a society or association in the previous 10 years.
Search Strategy
Summary of Recommendations of Each Guideline
Selection of Guidelines
USB, AS and HP independently carried out the screening process. Removal of duplicates was done manually. USB and AS examined and evaluated titles and abstracts to determine the ones to be selected as per eligibility criteria. Full text of the articles was evaluated, and the data were extracted for inclusion. Inconsistencies were sorted by discussing with the third author (HP). Cohen’s kappa evaluated reliability across title/abstract and full text review stages which were found to be 0.89 and 0.88 respectively.
Data Extraction
USB gathered information from the included guidelines which was independently cross checked by AS. Inconsistencies were discussed and resolved by authors AC & HP. The information collected from the studies consisted of: Title, Year, Developing Organization, Country/Region and Summary/Recommendations.
Guideline Assessment Using the AGREE II Instrument
The assessment of the guidelines in this review was carried out using the AGREE II instrument by four appraisers. The instrument comprises 23 key items within six domains and two additional global rating items. The 23 items within the six domains are rated on a 7- point scale, the scores of which are assigned based on reporting quality and completeness. The overall assessment using the AGREE II instrument involves two additional items: The first is to ask the appraiser to judge the overall quality of each of the reviewed guidelines on a 1-7 scale and the second is to ask the appraiser if they would recommend the use of the guidelines with yes, yes with modifications or no.
The four appraisers who carried out the assessment were professionals with vast experience in tobacco cessation and tobacco control, dental public health professionals and clinicians with experience of evidence-based research using AGREE II instrument. The selection of the appraisers was carried out to ensure independent reviewing of the guidelines by experts from different domains but with experience pertaining to this form of research. The guidelines included in this review were independently rated by four appraisers to increase the reliability and accuracy of the assessment.
Calculating the Domain Scores
The calculation of the quality scores was done for each of the six domains in AGREE II by summing the scores of the domain’s items and scaling the total score as a percentage of that domain’s possible score. All the six domain scores were independent and therefore, were not aggregated into 1 score.
Results
Guideline Selection
This systematic review identified a total of 493 records after a comprehensive search in four databases published between 2014 and 2024. Of the 493 records, 45 were duplicates and were removed. The remaining 448 records were assessed and after initial screening of the records, 428 records not meeting the including criteria were subsequently removed. The full text of the remaining 20 guidelines were read and finally all 20 guidelines were included in the final analysis. The flowchart of the screening process is reported in Figure 1. Flowchart of Records Screening Through Review Process
Characteristics of the Guidelines
The characteristics of these guidelines have been reported in Table 1. This study included guidelines which were carried out between the years 2014 and 2024. Five guidelines were from the United States of America, four from Australia, two from India & United kingdom, one from Bhutan, Malaysia, New Zealand, Ireland, Switzerland while the remaining from Asia and Europe region.
Mean Domain Score for Each Guideline
Mean AGREE II Scores Across Different Domains for all Included Guidelines
The overall assessment scores were highest for the guidelines developed by CPG Tobacco Disorder Malaysia (2016), Hellenic Center for Disease Control & Prevention (2017) and National Clinical Guideline Dublin (2022), whereas the lowest score assigned to the Tobacco Cessation Guidelines by BlueCross BlueShield of Oklahoma (2019) and American Thoracic Society (Medications for smoking cessation, 2020). The guidelines not recommended were developed by Primary care respiratory medicine (2017), Tobacco Cessation Guidelines by BlueCross BlueShield of Oklahoma (2019), American Thoracic Society (Medications for smoking cessation, 2020), Smoking Cessation Guidelines Queensland (2024). Guidelines by the American Association for Respiratory Care (2014), Ministry of Health, Royal Government of Bhutan (2014), Ministry of Health Malaysia (2016), Hellenic Center for Disease Control & Prevention (2017), Department of Health, Dublin (2022), National Resource Centre for Oral Health and Tobacco Cessation (2022), World Health Organization (2024) and National Institute for Health and Care Excellence (2024) were strongly recommended for implementation. However, modifications were suggested in the guidelines developed by Jordanian Ministry of Health, American Thoracic Society (general recommendations), Ministry of Health, New Zealand Government, The Royal Australian New Zealand College of Psychiatrists, National Comprehensive Cancer Network, National Tobacco Control Programme, Ministry of Health and Family Welfare and Pharmaceutical Society of Australia.
Discussion
This systematic review evaluated the quality of existing guidelines on tobacco cessation by assessing their methodological rigor, comprehensiveness, and practical applicability. The findings from this review underscore both strengths and limitations across the guidelines, offering valuable insights into areas where tobacco cessation guidance can be improved to optimize clinical practice and public health outcomes.
The guidelines issued by the Ministry of Health Malaysia, Hellenic Center for Disease Control & Prevention and Department of Health Dublin received an overall score of 7. All three guidelines are much detailed and have analysed the quality of available evidence on tobacco cessation. Additionally, guidelines published by the National Resource Centre for Oral Health and Tobacco Cessation, World Health Organization and National Institute for Health and Care Excellence received an at par overall score of 6 and were recommended for use.
Considering the mean domain scores, the highest scores were reported in the “Clarity of Presentation” domain which deals with the language, structure and format of the guidelines. Five guidelines reportedly scored 100% for clarity of presentation. In terms of the individual guidelines, the highest scores were reported by National Clinical Guideline Dublin (2022) 13 and lowest scores were reported by American Thoracic Society (2020). 11 While the national clinical guidelines analysed the quality of available evidence on cessation it also highlighted potential barriers and enablers to the implementation of recommendations. Overall, only four guidelines were not recommended based on the assessment criteria. Guidelines published by the American Thoracic Society in 2020 received the lowest score in the “Applicability” domain. Considering the development and implementation of recommendations as separate procedures could be the reason for low “Applicability” domain scores. In domain 6, or “Editorial Independence”, the American Thoracic Society recommendations received the lowest score, which is another significant finding. One possible explanation for this could be a lack of knowledge about funding sources and conflicts of interest.
The review identified a wide variety of tobacco cessation guidelines, published by a range of international health organizations, government agencies, and professional societies. Notable variation in methodological quality, the clarity of recommendations, and the consistency of key treatment strategies were reported among the guidelines on tobacco cessation. Several guidelines adhered to the clarity of presentation and scope and purpose of the guidelines. However, weakness in critical areas such as editorial independence and applicability was demonstrated. One of the most striking findings was the inconsistencies in the Rigour of Development of the guidelines. The rigour of development domain is considered as one of the most important domains and primarily consists of systematic methods to search the evidence, describing the criteria for selecting the evidence, strengths and limitations of the body of evidence, method for formulating the recommendations, whether the health benefits, side effects, and risks have been considered in formulating the recommendations, explicit link between the recommendations and the supporting evidence, whether the guidelines have been externally reviewed by experts and a procedure for updating the guideline is provided. This review thus highlights the need for focusing and strengthening these domains. The lower scores of the domains in these guidelines may be attributed to the deficiencies during the initial and formulation phases of the guidelines. The variability in the quality of the guidelines may be reflective of differences in the guideline development process, evidence synthesis and stakeholder engagement.
The AGREE-II tool, which was used in the current review, is reliable and valid. It has also been used previously to evaluate guidelines in dentistry pertaining to vital pulp therapy, 24 oral health care during pregnancy 25 and traumatic dental injuries 26 to name a few. Additionally, It is also accepted by the World Health Organization as the standard for evaluating guidelines. 24 For increased dependability, the makers of AGREE tool suggested that each guideline be evaluated by at least two, and ideally four, appraisers. This justifies the methodology of the current review as four experienced public health experts evaluated each guideline. Before the assessment, each of the four assessors was given instructions on how to utilize the internationally recognized AGREE II instrument.
While some guidelines included tailored recommendations for vulnerable groups, others either offered minimal guidance or did not address vulnerable populations at all. The heightened risk of tobacco uses with tobacco use in vulnerable groups however reflects the need for more specialised recommendations and guidelines by either mentioning them or centred only on subgroups. It is also important to systematically address the applicability domain in the future guidelines considering how recommendations can be implemented in practice.
Additionally, it is imperative to recognize that if a guideline does not include all relevant, valid, and up-to-date evidence, it may be considered outdated. Guidelines must therefore be updated frequently to be valid.
Strengths and Limitations
Despite the observed variations, several guidelines demonstrated notable strengths. The incorporation of high evidence-based research helped ensure that recommendations were based on scientific evidence. The use of expert panels from diversified fields in the development of many guidelines added credibility to the recommendations. The guidelines have also addressed the barriers to quitting and the strategies to overcome them. Moreover, guidelines from certain regions and organizations, exhibited actionable recommendations that could be adopted in various healthcare settings.
The lack of transparent description of evidence review process, low rigor of evidence in some guidelines, lack of detailed conflict of interest disclosures and funding sources raise questions about the integrity. Additionally, the inclusion criteria restricted the review to guidelines published in English which may have excluded relevant guidelines in other languages.
Implications for Clinical Practice and Policy
This review underscores the importance of high-quality, evidence-based guidelines in guiding tobacco cessation efforts and highlights several key areas for improvement. It is important for healthcare providers to be equipped with guidelines that are not only evidence-based but also clear and actionable in their recommendations. Moreover, future guidelines should prioritize the inclusion of recommendations tailored to specific subpopulations and address the unique challenges they face in quitting tobacco use.
According to the current review’s findings, some areas require more development, particularly the “Rigor of Development” domain, which integrates evidence-based research and is crucial for bolstering the guidelines. Going forward, this could help clinicians make decisions, which is crucial.
Conclusion
In conclusion, this systematic review provides a comprehensive assessment of the quality of guidelines on tobacco cessation, identifying both strengths and areas for improvement. Further guidelines developed should address the gaps identified in this review and be both evidence-based and feasible to implement in diverse clinical contexts.
Footnotes
Author Contributions
Upendra Singh Bhadauria: Formal Analysis; Investigation; Methodology; Validation; Writing – original draft; Writing – editing and reviewing. Akshat Sachdeva: Conceptualization; Formal Analysis; Investigation; Methodology; Writing – editing and reviewing. Harsh Priya: Conceptualization; Investigation; Data Curation; Formal Analysis; Methodology; Project Administration; Resources; Supervision; Validation; Writing –editing and reviewing. Amrita Chawla: Supervision; Validation; Writing –editing and reviewing. Puneet Chahar: Investigation; Methodology; Writing – editing and reviewing. Rana Jugdeep Singh: Investigation; Methodology; Writing – editing and reviewing.
Funding
The authors received no financial support for the research, authorship, and/or publication of this article.
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.