ABSTRACT
Anemia is an important public health and clinical problem. Observational studies have linked iron deficiency and anemia in children with many poor outcomes, including impaired cognitive development. In this study, we summarize the evidence for the effect of daily iron supplementation on cognitive performance in primary-school-aged children. We searched electronic databases (including MEDLINE and Wangfang database) and other sources (August 2015) for randomized and quasi-randomized controlled trials involving daily iron supplementation on cognitive performance in children aged 5-12 years. We combined the data using random effects meta-analysis. We identified 3219 studies; of these, we evaluated 5 full-text papers including 1825 children. Iron supplementation cannot improve global cognitive scores (Mean difference 1.05, 95% confidence interval [CI] -2.69 to 4.79, P<0.01). Our analysis suggests that iron supplementation improves global cognitive c outcomes among primary-school-aged children is still unclear.
ABSTRACT
Though many studies were published to assess the relationship between p21 Ser31Arg polymorphism and cervical cancer, there was no definite conclusion on this association. To provide a quantitative assessment of the relationship between p21 Ser31Arg polymorphism and cervical cancer, we performed a meta-analysis of 10 eligible studies (1,539 cases and 2,161 controls). All those 10 studies were from Asians. The odds ratios (OR) with 95% confidence intervals (95%CIs) were used to assess the strength of the association, and the pooled ORs were calculated for the codominant model (ArgArg vs. SerSer), the dominant model (ArgArg/SerArg vs. SerSer), and the recessive model (ArgArg vs. SerSer/SerArg). Meta-analysis of those 10 studies showed that there was no association between p21 Ser31Arg polymorphism and cervical cancer risk in Asians under all three models (ArgArg vs. SerSer: OR = 1.04, 95%CI 0.66-1.65, P = 0.86, I(2) = 78%; ArgArg/SerArg vs. SerSer: OR = 0.93, 95%CI 0.66-1.30, P = 0.66, I(2) = 81%; ArgArg vs. SerSer/SerArg: OR = 1.20, 95%CI 0.84-1.73, P = 0.32, I(2) = 72%). Sensitivity analysis performed by omitting each study in turn showed that the pooled results were stable. In summary, there is no association between p21 Ser31Arg polymorphism and cervical cancer risk in Asians. Further studies are needed to assess the possible association between p21 Ser31Arg polymorphism and cervical cancer risk in Caucasians.