Abstract Through the interpretation of the new sensitivity analysis method E-value, a simple and practical sensitivity analysis method for observational research is introduced to readers. In this method, Relative Risk (RR) was used as the main research index to construct a statistical model of RR sensitivity analysis, so as to predict the minimum correlation strength of unknown confounders with exposure factors and outcomes that can explain away the research results (RR values). The method also extended RR to sensitivity analysis of Odds ratio, Hazard ratio and mean of outcome changes through statistical transformation. This method provides a simple and reliable method for sensitivity analysis of observational research, and it is suggested to provide corresponding results of sensitivity analysis in future observational research reports and papers, but it should be noted that this sensitivity analysis cannot replace rigorous scientific research design.
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