INTRODUCTION During the last two decades, several studies have been published regarding the prevalence of tobacco smoking among college students in the Kingdom of Saudi Arabia (KSA). This systematic review and meta-analysis is intended to determine and examine the smoking prevalence in Saudi college students from 2010–2018. METHODS PubMed, Science Direct, APA PsycNET, Web of Science, and CINAHL were used to search for published articles reporting the smoking prevalence among Saudi college students. After eliminating irrelevant articles, investigators independently assessed the quality of each article, based on Russell & Gregory guidelines. MetaXL software was used to calculate the pooled prevalence among included studies, using the IVhert model. Heterogeneity among the included studies was evaluated, using I 2 statistic. Sensitivity analyses were conducted between male and female genders. RESULTS Of the 295 published articles, 29 articles used a cross-sectional design to determine smoking prevalence among Saudi college students. Most of the studies were conducted in Riyadh at health-science-related colleges; the rest were performed in different cities and colleges. The meta-analysis showed that the pooled estimate of smoking prevalence among college students in the KSA was 17% (95% CI: 11–23%). Saudi male students had a prevalence rate of 26% (95% CI: 24–29%), whereas for Saudi female students the prevalence was 5% (95% CI: 3–7%). CONCLUSIONS Smoking among Saudi college students was higher than in the majority of regional countries (e.g. Iran). Saudi male students had a higher smoking prevalence than Saudi female college students. Additionally, studies that reported a high prevalence targeted students in specific disciplines. Public health authorities in the KSA should develop a surveillance system that monitors the prevalence of tobacco smoking on campuses. A surveillance system of monitoring tobacco use among Saudi college students could be beneficial in determining the degree of the tobacco problem and in improving current tobacco control programs.

To promote fruit and vegetable (FV) intake among participants, the USDA Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) implemented a comprehensive food package revision in 2009. However, to our knowledge, no studies have systematically explored the factors related to FV purchases and/or consumption among WIC participants in the post-2009 revision era. To fill this knowledge gap, we conducted a systematic literature review using PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Central Register of Controlled Trials, and Web of Science using key search terms. Studies published from January 1, 2007, through February 28, 2019, were included, since an interim rule for the WIC food package revision was issued in 2007. This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format. The articles were grouped based on main themes or factors, settings, design, study years, and sample size. Thirty-nine articles met the inclusion criteria. Seven main themes or factors related to FV purchases and/or consumption in WIC participants were identified in these articles. The 2009 WIC food package revision was the most-studied factor (n = 9). National and state-level studies showed a consistently positive relation between the 2009 revision and FV purchases and/or consumption. However, some studies did not find a positive relation. State-level policy variations can be exploited as natural experiments to assess the causality of state-level factors in WIC participants’ FV purchases or consumption. The majority of the included studies were limited in being local (n = 26, 66.7%), cross-sectional (n = 29, 74.4%), or having sample sizes <1000 (n = 25, 64.1%), which could explain the diverse results regarding the relation between FV purchases and/or consumption and various factors, including individual, store, and program characteristics.

In this study, cement-treated waste sand as a by-product material produced from Al-Ahsa quarries (Saudi Arabia) was experimentally tested and investigated as a base course material for the foundation of structures and roads. The study aimed to use the waste sand as a construction material by improving its strength, bearing capacity, and stiffness. The waste sand was mixed with different percentages of Portland cement content (0, 2, 4, 6, and 8%) at the maximum dry density and optimum water content of the standard Proctor compaction conditions of a non-treated sample. Unconfined compressive strength and California Bearing Ratio (CBR) tests for different curing times were conducted. X-ray diffraction (XRD), laser-scanning microscopy (LSM), and X-ray spectroscopy (XPS) were used to explore the microstructure and composition of the treated sand. The results showed that the compressive strength, initial tangent modulus, and CBR of the treated sand increase with the increase in cement content and curing time. Furthermore, good correlations were established among the strength, initial tangent modulus, and CBR. Based on the obtained results, cement-stabilized waste sand is a potential material for use in construction. This is expected to save the environment and reduce the cost of road construction.