title: Prevalence of Cannabis Lifetime Use in Iranian High School and College Students: A Systematic Review, Meta-Analyses, and Meta-Regression.
abstract: Cannabis is the most widely used substance in the world. This study aimed to estimate the prevalence of cannabis lifetime use (CLU) in high school and college students of Iran and also to determine factors related to changes in prevalence. A systematic review of literature on cannabis use in Iran was conducted according to MOOSE guideline. Domestic scientific databases, PubMed/Medline, ISI Web of Knowledge, and Google Scholar, relevant reference lists, and relevant journals were searched up to April, 2014. Prevalences were calculated using the variance stabilizing double arcsine transformation and confidence intervals (CIs) estimated using the Wilson method. Heterogeneity was assessed by Cochran's Q statistic and I(2) index and causes of heterogeneity were evaluated using meta-regression model. In electronic database search, 4,000 citations were retrieved, producing a total of 33 studies. CLU was reported with a random effects pooled prevalence of 4.0% (95% CI = 3.0% to 5.0%). In subgroups of high school and college students, prevalences were 5.0% (95% CI = 3.0% to -7.0%) and 2.0% (95% CI = 2.0% to -3.0%), respectively. Meta-regression model indicated that prevalence is higher in college students (β = 0.089, p < .001), male gender (β = 0.017, p < .001), and is lower in studies with sampling versus census studies (β = -0.096, p < .001). This study reported that prevalence of CLU in Iranian students are lower than industrialized countries. In addition, gender, level of education, and methods of sampling are highly associated with changes in the prevalence of CLU across provinces.
authors.affiliation: Ilam University of Medical Sciences, Ilam, Iran Shahid Beheshti University of Medical Science, Tehran, Iran Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Milad
authors.initials: M
authors.lastname: Nazarzadeh
authors.affiliation: Ilam University of Medical Sciences, Ilam, Iran.
authors.forename: Zeinab
authors.initials: Z
authors.lastname: Bidel
authors.affiliation: Simon Fraser University, Burnaby, British Columbia, Canada Sabzevar University of Medical Sciences and Health Services, Sabzevar, Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Mosavi Jarahi
authors.affiliation: Shahid Beheshti University of Medical Science, Tehran, Iran.
authors.forename: Keihan
authors.initials: K
authors.lastname: Esmaeelpour
authors.affiliation: Ilam University of Medical Sciences, Ilam, Iran waliehmenati@yahoo.com.
authors.forename: Walieh
authors.initials: W
authors.lastname: Menati
authors.affiliation: Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Ali Asghar
authors.initials: AA
authors.lastname: Shakeri
authors.affiliation: Ilam University of Medical Sciences, Ilam, Iran.
authors.forename: Rostam
authors.initials: R
authors.lastname: Menati
authors.affiliation: Ilam University of Medical Sciences, Ilam, Iran.
authors.forename: Sattar
authors.initials: S
authors.lastname: Kikhavani
authors.affiliation: Lorestan University of Medical Science, Khorramabad, Iran.
authors.forename: Kourosh
authors.initials: K
authors.lastname: Saki
mesh_terms: D005260:Female; D006801:Humans; D007492:Iran / Q000453:epidemiology; D008297:Male; D008385:Marijuana Smoking / Q000453:epidemiology*; D015995:Prevalence; D012737:Sex Factors; D013334:Students / Q000706:statistics & numerical data*; D014495:Universities
keywords: cannabis; meta-analyses; meta-regression; prevalence; students