Objective To systematically evaluate the risk factors and population attributable risk of children leukemia in China, so as to provide references for policy-making. Methods The case-control studies about risk factors of children leukemia in China were searched in PubMed, CNKI, CBM, VIP and WanFang Data from inception to December 2011. According to the inclusion and exclusion criteria, two reviewers independently screened articles, extracted data, and evaluated the quality of the included studies. Then Meta-analysis was performed using STATA 11 and Excel 2003. The pooled odds ratio (OR) and 95% confidence interval (95%CI) of each risk factor were calculated, and the population attributable risk percent (PARP) based on the exposure rate of the risk factors was computed, and published bias was estimated according to the fail-safe number. Results A total of 15 case-control studies were included. The first 5 risk factors related to children leukemia were: dwelling environmental pollution (OR=2.782, 95%CI 2.268 to 3.413), house decoration (OR=2.525, 95%CI 1.736 to 3.673), maternal exposure to chemical hazards (OR=2.428, 95%CI 1.976 to 2.985), family history of tumor (OR=2.212, 95%CI 1.677 to 2.919), and child exposure to electromagnetic field around dwelling (OR=2.144, 95%CI 1.761 to 2.610). Factors with higher PARP were influenza history (37.56%), house decoration history (32.95%), X-ray exposure history (20.47%), and chemical hazards exposure history (17.37%). The fail-safe number showed the results were generally reliable. Conclusion In order to prevent and control children leukemia, positive and effective measures should be taken in the following aspects: strengthening child care, avoiding unnecessary X-ray exposure, and providing good living environment.
Objective To systematically review the evidence of the factors associated with self-rated health (SRH) and estimating the population attributable risk proportion (PARP) of interests in the elderly. Methods MEDLINE, EMbase, CBM, CNKI, VIP and WanFang Data were searched (from January 1960 to April 2011) for relevant literature. The combined effect on each factor associated with poor SRH was expressed as RR or OR (95%CI). The contribution of each factor to poor SRH in the elderly population was estimated with PARP. Meta-analysis was performed using RevMan 5.1 software. Results Twelve studies involving a total of 35 349 participants aged 60 or above were eligible in this systematic review. Ten studies were conducted in China and the rest two studies were from the USA and Brazil. Of them, only one was prospective cohort study and 11 studies were cross-sectional. The results of meta-analysis showed that the main factors associated with poor SRH in the elderly were dependency, diabetes and coronary heart disease with the corresponding OR and 95%CI as 12.10 (6.31, 23.20), 6.49 (3.21, 13.09) and 5.60 (1.07, 29.42), respectively. However, the top three factors contributing to poor SRH in the elderly population were coronary heart disease, having illness half one year ago and chronic disorders with the corresponding PARP as 53.91%, 52.56%, and 50.09%, respectively. It was not possible to perform sub-group analysis because of the limited quantity of studies on each factor associated with poor SRH. Conclusion Based on the current available evidence, it appears that chronic disorders are closely related to poor SRH and contribute most in the elderly population. However, due to the limitation of the included predominantly cross sectional studies which are not enough for causal argument, it is insufficient to determine the association of many factors with poor SRH. Further high-quality prospective cohort studies are needed.
ObjectivesTo systematically review the association between pregnancy-induced hypertension (PIH) and preterm birth in mainland China.MethodsPubMed, The Cochrane Library, ScienceDirect, Web of Science, CBM, CNKI, WanFang Data and VIP databases were electronically searched to collect studies on the association between PIH and preterm birth in mainland China from January, 2007 to March, 2019. Two reviewers independently screened literature, extracted data and assessed risk of bias of included studies; then, meta-analysis was performed by using Stata 12.0 software.ResultsA total of 48 studies were included, involving 43 276 cases of premature birth, 527 995 cases of full-term control group, in which there were 3 446 cases of PIH in premature delivery, with a prevalence rate of 7.96%. There were 14 099 cases of PIH in the full-term control group, with a prevalence rate of 2.67%. The results of meta-analysis showed that PIH was associated with preterm birth (OR=3.27, 95%CI 2.64 to 4.05, P<0.001). The overall population attributable risk was 13.0%. Subgroup analysis was conducted for different study types, and the results were unaltered.ConclusionsThe current evidence shows that PIH is associated with preterm birth. During pregnancy, the management and intervention of pregnant females with gestational hypertension should be strengthened, and active treatment should be supervised to prevent the occurrence of premature birth.