Etiological and prognostic studies always directly reported effect size with its 95% confidence interval, hence, data transformation was needed when performing meta-analysis based on these studies. Using the data of risk ratio, hazard ratio, odds ratio and 95% confidence interval as an example, this paper introduces the process of using RevMan 5.3 software to convert data and perform meta-analysis.
Objective To estimate the incidence of suicidal ideation of Chinese medical students in mainland China over the past ten years by meta-analysis, so as to provide references for suicide prevention and mental health education in Chinese medical students. Methods PubMed, CNKI, WanFang Data and CBM databases were searched for studies investigating the prevalence of suicidal ideation among Chinese medical students in mainland China from January 1st, 2007 to 31st May, 2017. After study selection according to inclusion and exclusion criterion, data extraction and quality assessment, meta-analysis was conducted using Stata 12.0 software. Heterogeneity was evaluated by performing subgroup analyses and meta-regression. We also used sensitivity analysis to determine the influence of individual studies on the overall prevalence estimates. Results A total of 30 studies with 58 757 participants were included, the individual-study incidence of suicidal ideation ranged from 0.84% to 41.35%, with significant between-study heterogeneity detected (I2=99.1%, P<0.001), and the pooled incidence by random-effects model was 12.51% with 95%CI 9.72% to 15.60%. Univariate and multivariate meta-regression revealed that instruments were related to heterogeneity (P<0.01), but other study-level covariates did not contribute to heterogeneity (P>0.1). Conclusion The incidence of suicidal ideation among medical students in mainland China is relatively high, calling more attention to this concern and actions in response for suicide prevention and mental health education in Chinese medical students.
The association between single nucleotide polymorphism and disease is a typical representation of genetic association studies. Compared with the traditional dichotomous data, single nucleotide polymorphism data has its own characteristics, and 5 genetic models are commonly performed in meta-analysis. In this paper, we show how to use the " meta” package in R software to conduct meta-analysis of single nucleotide polymorphism research through examples.
To perform a meta-analysis of single nucleotide polymorphism needs to calculate gene frequency. This paper employs allele model as an example to introduce how to calculate gene frequency and display the process of a meta-analysis of single nucleotide polymorphism data using Review Manager 5.3 software.
Objective To systematically review the relationship between periodontal disease and gastric cancer risk. Methods We retrieved PubMed, EMbase, CNKI, WanFang Data, VIP, and CBM databases to collect studies about the correlation between periodontal disease and gastric cancer from inception to January 31st, 2017. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then, meta-analysis was performed using RevMan 5.3 software. Results Five studies were included. The results of meta-analysis showed that there was no significant correlation between periodontal disease and gastric cancer (RR=0.99, 95%CI 0.83 to 1.19, P=0.93). Sensitivity analysis showed good stability. Subgroup analysis showed that the type of study, race and type of effect size have no statistically impact on the outcome, there was no significant correlation between periodontal disease and gastric cancer. Conclusion According to the current evidence, periodontal disease probably is not a risk factor of gastric cancer. Due to limited quality and quantity of the included studies, more high quality studies are needed to verify above conclusion.
ObjectiveTo systematically review the association between periodontal disease and the incidence risk of colorectal cancer (CRC).MethodsPubMed, EMbase, WanFang Data and CNKI databases were searched to collect cohort studies and case-control studies for the association between periodontal disease and the incidence risk of CRC from inception to February 28th, 2017. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies, then, meta-analysis was performed by using RevMan 5.3 software.ResultsA total of 5 prospective cohort studies were included. The results from adjusted data based meta-analysis showed that the periodontal disease was not associated with the incidence risk of CRC (RR=1.14, 95%CI 0.88 to 1.49, P=0.32).ConclusionsThe current evidence suggests that periodontal disease is not associated with the risk of CRC.
ObjectivesTo systematically review the efficacy and safety of 3D laparoscopic in the treatment of colorectal cancer.MethodsPubMed, EMbase, The Cochrane Library, CBM, VIP, WanFang Data and CNKI databases were electronically searched online to collect clinical trials of 3D laparoscopic in the treatment of colorectal cancer from inception to September 1st, 2018. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Meta-analysis was then performed using RevMan 5.3 software.ResultsA total of 26 trials, including 4 randomized controlled trials and 22 cohort studies were included. The results of meta-analysis showed that: compared with 2D laparoscopic, 3D laparoscopic had shorter operative time (MD=–16.32, 95%CI –22.61 to –10.03, P<0.000 01), less amount of blood transfusion in operation (MD=–10.80, 95%CI –19.93 to –1.66, P=0.02), more lymph node dissection (MD=0.88, 95%CI 0.30 to 1.45, P=0.003), shorter recovery time of gastrointestinal function (MD=–0.18, 95%CI –0.31 to –0.04, P=0.01), lower incidence of postoperative complication (OR=0.63, 95%CI 0.44 to 0.89, P=0.009), and fewer days in hospital (MD=–0.84, 95%CI –1.40 to –0.28, P=0.003). Additionally, there was no significant difference in hospitalization costs (MD=–0.01, 95%CI –0.23 to 0.21, P=0.94).ConclusionsCurrent evidence shows that, compared with 2D laparoscopy, 3D laparoscopy assisted colorectal cancer surgery has obvious advantages such as less bleeding during operation, shorter operation time, lower incidence of complications after operation, shorter hospitalization time and no increase in hospitalization expenses. Due to limited quality and quantity of the included studies, more high quality studies are required to verify above conclusions.
ObjectiveTo analyze the trend of disease burden of colorectal cancer (CRC) in China from 1990 to 2019.MethodsData was obtained from Global Burden of Disease Study 2019 (GBD 2019). Incidence, mortality, disability-adjusted life year (DALY), years of life lost (YLL), years lived with disability (YLD), and their corresponding standardized rate and annual average percentage change (AAPC) were used to describe the changes of disease burden of colorectal cancer in Chinese population between 1990 and 2019.ResultsCompared with 1990, the number of new cases, standardized incidence, the number of deaths and standardized mortality of CRC in China in 2019 increased by 474.03%, 144.01%, 230.14%, and 36.15%, respectively. The standardized mortality and standardized incidence of CRC in China had reached and gradually exceeded the global level since 2010. From 1990 to 2019, the overall standard incidence (AAPC=3.6%, P<0.05), standard mortality rate (AAPC=1.4%, P<0.05), and the standard DALY rate (AAPC=1.2%, P<0.05) of CRC in China showed an increasing trend. The incidence, mortality and DALY rates of males were higher than those of females, and gradually increased with age. Compared with 1990, the DALY, YLL, and YLD of CRC in 2019 increased by 134.3%, 127.69%, and 445.00%, and their corresponding standardized rates increased by 30.53%, 27.03%, and 187.29%, respectively, showing an overall upward trend.ConclusionsFrom 1990 to 2019, the standardized incidence rate and standardized mortality rate of colorectal cancer in China have had a continuously increasing trend, and males and the elderly are high-risk groups. To reduce the burden of colorectal cancer in China, effective measures should be taken for prevention and management.
ObjectiveTo develop the questionnaire and test its reliability for investigating route, prevention, and control of SARS-CoV-2 infection in medical staffs.MethodsThis questionnaire was development based on the COVID-19 relevant guidelines, official documents issued by the National Health Committee of the People's Republic of China, and published studies. The development group performed repeated discussions and drafted the first questionnaire, then performed expert consultation and revised the draft according to their suggestions. Eventually, some frontline medical staffs were invited to carry out pre-test investigation of the questionnaire and test its reliability.ResultsThe first draft included 48 items; 18 experts were invited in the first round questionnaire and 10 experts in the second round questionnaire. The positive coefficient of experts in these two rounds was both greater than 75%, and the authority coefficient of experts' opinions was greater than 0.70. The variation coefficient of these items was between 0.00 and 0.35, the coordination coefficient of experts was 0.193 (P<0.05). The experts of above two rounds put forward 14 suggestions for text modification or adjustment options of some items; after the development group held repeatedly discussions, a total of 8 items were performed secondary consultation and finally reached consensus. The final questionnaire included two domains of questionnaire before and after confirmed diagnosis. The domain "before confirmed diagnosis" covered 4 sections and 29 items involving infectious cause, plan and knowledge of prevention and control, and psychological symptoms. The domain "after confirmed diagnosis" covered 5 sections and 21 items, included symptoms, treatment, and psychological status after diagnosis; impact on the surrounding environment and people, and awareness of protection after infection. The pre-test results showed that the total items were considerably numerous, some items were difficult to understand, some laboratory results and treatment conditions were ambiguous, etc. After modification and re-testing, the test-re-test reliability of each domain was between 0.74 and 0.93, and the overall re-test reliability of the questionnaire content was 0.82.ConclusionsThis research has developed a questionnaire for investigating infection process, prevention and control of SARS-CoV-2 infection in medical staff, and the items considered two domains prior to and after confirmed diagnosis. The reliability and practicability of the questionnaire are acceptable.