Chi-square research was utilized to test to have variations in the latest incidence between men and women, age range, or any other subgroups

S.: n=step onestep three,689) split up from the try sized for every country increased of the brand new loads

According to the complex sampling design of the GYTS, the weighted prevalence estimates and their 95% confidence intervals (CI) of smokeless tobacco use in each country were calculated using original sampling weights, strata, and pripling units provided in the datasets using the SAS PROC SURVEYFREQ procedure. The original weights were calculated by the following formula: W=W₁*W₂*f₁*f₂*f₃*f₄, where W₁ is the inverse of the selection probability of each school; W₂ is the inverse of selection probability of each class; f₁ is the school-level non-response adjustment factor calculated by school enrolment size; f₂ is the class-level non-response adjustment factor for each school; f₃ is the student-level non-response adjustment factor for each class; f₄ is the post-adjustment stratification factor calculated by grade and sex. We rescaled the original weights to calculate the overall and subgroups’ prevalence of smokeless tobacco use based on each country’s sample size. The rescaled weights were calculated as the maximum country sample size (i.e., U. Chi-square trend test was used to examine the secular trend in the prevalence with consideration of data from all surveys in each country between 1999 and 2019. The prevalence estimates of secular trends were calculated per 5 calendar years. Multivariable logistic regression models were used to assess the association of potential associated factors (sex, age, cigarette smoking, other tobacco product use, parental smoking, smoking status of closest friends, tobacco advertisement exposure, being offered free tobacco products, being taught about dangers of smoking, and World Bank income level) with current smokeless tobacco use, and the code for each variable is shown in Additional file 1: Table S1. In order to correct the overall probability of type I error in multiple statistical tests (?=0.05), the Bonferroni’s correction was used to adjust the critical significance level of each statistical test. The corrected critical significance level was equal to the original critical significance level (0.05) divided by the number of tests performed. A two-sided P-value less than the Bonferroni’s corrected critical significance level was regarded as statistical significance and SAS 9.4 (SAS Institute, Cary, NC, US) was used for all analyses.

Overall performance

A total of 450,691 teenagers (boys: 51.4%) old 12–16 age off 138 places surveyed ranging from 2010 and you may 2019 had been incorporated to help you imagine the newest prevalence of newest smokeless cigarette smoking and you can its associated products. Certainly 138 included nations surveyed this present year–2019, 23 (16.7%) was on the African region, 30 (21.7%) regarding the Western part, 23 (16.7%) throughout the Eastern Mediterranean part, 31 (twenty two.5%) throughout the Eu area, 9 (six.5%) from the Southern-Eastern Western area, and you can twenty-two (15.9%) on the West Pacific part (Additional document step one: Dining table S2).

According to the newest analysis regarding 138 nations this year-2019, the entire frequency off newest smokeless using tobacco is cuatro.4% (95% CI 4.0–4.9), with 5.7% (5.1–six.3) having guys, 3.1% (dos.6–step three.5) for women, step 3.9% (step 3.5–4.4) to possess teenagers aged several–fourteen age, and 5.cuatro% (cuatro.8–5.9) for these aged 15–16 decades (Table 1). The newest prevalence varied somewhat around the all the 138 countries (off 0.0% into the Tokelau to 51.6% inside Kiribati), and also by gender and you may generation within this each of really regions (Fig. 1, and additional document 1: Fig. S2 and you can Table S3). The new incidence is actually nearly 5 times higher certainly current smokers in contrast to low-smokers (fourteen.3% vs. step 3.0%), and almost seven moments large one of almost every other tobacco equipment pages opposed that have low-profiles (twenty-two.5% compared to. step 3.2%). This new prevalence one of teenagers whose both parents (9.8%), and mother only (5.6%) used is actually more than those people whoever father merely (4.4%) and none father or mother (4.7%) used. The brand new prevalence is higher from the Southern-East Western area (six.1%), accompanied by this new African area (5.4%), and you may low throughout the West Pacific area (dos.0%). The brand new prevalence was higher when you look at the all the way down-middle-earnings countries (5.5%), accompanied by lower-money places (4.7%), and lower when you look at the high-income nations (2.8%) (Desk step 1).