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.
N-of-1 trials are prospective clinical randomized cross-over controlled trials with multiple rounds of trial phase alternation designed with regard to a single patient. N-of-1 trials can provide clinical decision-makers with high-level evidence of the comparison of effect of intervention measures. Recently, an international team composed of many scholars published a SPIRIT extension for N-of-1 trials list (SPENT 2019) on the BMJ, with the purposes of clarifying the content design and improving the integrity and transparency of N-of-1 trial protocols. This article showed a detailed interpretation of the 14 main extension sub-items of the SPENT 2019 list with specific cases, aiming to further standardize the publication of domestic N-of-1 trials.
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.