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Does liberalisation of cannabis policy influence levels of use in adolescents and young adults? A systematic review and meta-analysis.

ABSTRACT: OBJECTIVES:To examine the effect of cannabis policy liberalisation (decriminalisation and legalisation) levels of use in adolescents and young adults. DESIGN:Systematic review and meta-analysis. INCLUSION CRITERIA:Included studies were conducted among individuals younger than 25 years and quantitatively assessing consequences of cannabis policy change. We excluded articles: (A) exclusively based on participants older than 25 years; (B) only reporting changes in perceptions of cannabis use; (C) not including at least two measures of cannabis use; (D) not including quantitative data; and (E) reviews, letters, opinions and policy papers. PubMed, PsycINFO, Embase and Web of Science were searched through 1 March 2018. DATA EXTRACTION AND SYNTHESIS:Two independent readers reviewed the eligibility of titles and abstracts and read eligible articles, and four authors assessed the risk of bias (Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies). Extracted data were meta-analysed. The protocol was registered with PROSPERO. RESULTS:3438 records were identified via search terms and four via citation lists; 2312 were retained after removal of duplicates, 99 were assessed for eligibility and 41 were included in our systematic review. 13 articles examined cannabis decriminalisation, 20 examined legalisation for medical purposes and 8 examined legalisation for recreational purposes. Findings regarding the consequences of cannabis decriminalisation or legalisation for medical purposes were too heterogeneous to be meta-analysed. Our systematic review and meta-analysis suggest a small increase in cannabis use among adolescents and young adults following legalisation of cannabis for recreational purposes (standardised mean difference of 0.03, 95%?CI -0.01 to -0.07). Nevertheless, studies characterised by a very low/low risk of bias showed no evidence of changes in cannabis use following policy modifications. CONCLUSIONS:Cannabis policy liberalisation does not appear to result in significant changes in youths' use, with the possible exception of legalisation for recreational purposes that requires monitoring. TRIAL REGISTRATION NUMBER:CRD42018083950.

SUBMITTER: Melchior M

PROVIDER: S-EPMC6624043 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Does liberalisation of cannabis policy influence levels of use in adolescents and young adults? A systematic review and meta-analysis.

Melchior Maria M Nakamura Aurélie A Bolze Camille C Hausfater Félix F El Khoury Fabienne F Mary-Krause Murielle M Azevedo Da Silva Marine M

BMJ open 20190710 7

<h4>Objectives</h4>To examine the effect of cannabis policy liberalisation (decriminalisation and legalisation) levels of use in adolescents and young adults.<h4>Design</h4>Systematic review and meta-analysis.<h4>Inclusion criteria</h4>Included studies were conducted among individuals younger than 25 years and quantitatively assessing consequences of cannabis policy change. We excluded articles: (A) exclusively based on participants older than 25 years; (B) only reporting changes in perceptions ...[more]

PMID: 31296507

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Project description:ObjectiveTobacco use, particularly the initiation of smoking during adolescence and young adulthood, represents a significant public health concern in South Africa. This study aims to conduct a comprehensive review of published literature about tobacco use and behaviour among adolescents and young adults and to determine an aggregated prevalence estimate of tobacco use within this demographic.DesignSystematic review and meta-analysis.Data sourcesPubMed/MEDLINE, EMBASE, Cochrane Library, Scopus and Google Scholar were searched from 1 January 2000 through 31 October 2023.Eligibility criteriaStudies were eligible for inclusion if they were cross-sectional studies conducted in South Africa and measured the prevalence and determinants of tobacco use among adolescents and young adults aged 12-24 years.Data extraction and synthesisTwo reviewers independently extracted information for each article and saved it into an Excel spreadsheet. Risk of bias analysis was conducted using the Risk of Bias Assessment Tool for non-randomised studies. The methodology quality of each selected study was evaluated using the Joanna Briggs Institute checklist. The heterogeneity of prevalence estimates was assessed using I2 statistic (random-effects DerSimonian-Laid approach).ResultsOut of 73 articles identified, 12 articles were included in the analysis. The pooled prevalence of current tobacco use among South African adolescents and young adults was estimated to be 22%. The pooled prevalence of tobacco use among school dropouts, university students and secondary school learners was 51%, 20% and 16%, respectively. Stratifying using gender, boys (26%) were two times more likely to use tobacco than girls (13%).ConclusionThe elevated occurrence of tobacco usage among South African adolescents and young adults is a relevant public health concern. There is a need for more population-based prevalence studies at a national level to estimate the burden of tobacco use in South Africa.Prospero registration numberCRD42023428369.

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Does liberalisation of cannabis policy influence levels of use in adolescents and young adults? A systematic review and meta-analysis.

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Does liberalisation of cannabis policy influence levels of use in adolescents and young adults? A systematic review and meta-analysis.

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