Objectives
The objectives of this review and meta-analysis were twofold: first, to determine the prevalence of substance use among school-going children in Arab and African countries; and second, to highlight the considerable influence of variables such as the nation’s region and the timeframe of the study on the prevalence of substance use.
Methods
Research was sourced from Science Direct, Scopus, Web of Science, Google Scholar, and PubMed. Thirty-seven articles were incorporated in accordance with the PRISMA guidelines. This review included studies published from 2013 to 2023. The statistical meta-analysis was performed using Comprehensive Meta-Analysis ver. 3 software. Across 37 studies, the total number of study participants was 73,508.
Results
The meta-analysis revealed that tobacco was the most commonly used substance, with a prevalence of 16% (95% confidence interval [CI], 12.7%–20.02%). This was closely followed by alcohol, which had a prevalence of 15% (95% CI, 10.5%–22.8%), stimulants at 11.4% (95% CI, 7.4%–17%), khat at 10% (95% CI, 5.7%–15%), and cannabis at 8% (95% CI, 3.3%–18.4%). Notably, alcohol was the only substance that showed an increasing trend in prevalence from before to after 2019, rising from 13.3% (95% CI, 6.2%–26.1%) to 17% (95% CI, 10.2%–27%) (p<0.001). Additionally, the prevalence of substance use varied significantly between Arab and African countries (p<0.001).
Conclusion
Although the prevalence of substance use among school-going populations has significantly decreased over time, with the exception of alcohol, it is imperative that both African and Arab countries implement comprehensive measures and stringent laws to address the production and marketing of substances.

The exact factors predicting outcomes following traumatic brain injury (TBI) remain elusive. In this systematic review and meta-analysis, we examined factors influencing outcomes in adult patients with TBI, from 3 months to 1 year after injury. A search of four electronic databases—PubMed, Scopus, Web of Science, and ScienceDirect—yielded 29 studies for review and 16 for meta-analysis, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. In patients with TBI of any severity, mean differences were observed in age (8.72 years; 95% confidence interval [CI], 4.77–12.66 years), lymphocyte count (−0.15 109/L; 95% CI, −0.18 to −0.11), glucose levels (1.20 mmol/L; 95% CI, 0.73–1.68), and haemoglobin levels (−0.91 g/dL; 95% CI, −1.49 to −0.33) between those with favourable and unfavourable outcomes. The prevalence rates of unfavourable outcomes were as follows: abnormal cisterns, 65.7%; intracranial pressure above 20 mmHg, 52.9%; midline shift of 5 mm or more, 63%; hypotension, 71%; hypoxia, 86.8%; blood transfusion, 70.3%; and mechanical ventilation, 90%. Several predictors were strongly associated with outcome. Specifically, age, lymphocyte count, glucose level, haemoglobin level, severity of TBI, pupillary reaction, and type of injury were identified as potential predictors of long-term outcomes.