electronic health records (EHRs); retrospective studies; cohort studies; retrospective cohort studies; case-control studies; comparative effectiveness research


Applied Statistics | Biostatistics | Categorical Data Analysis | Multivariate Analysis | Statistical Methodology | Vital and Health Statistics


Electronic health records (EHRs) are an excellent source for secondary data analysis. Studies based on EHR-derived data, if designed properly, can answer previously unanswerable clinical research questions. In this paper we will highlight the benefits of large retrospective studies from secondary sources such as EHRs, examine retrospective cohort and case-control study design challenges, as well as methodological and statistical adjustment that can be made to overcome some of the inherent design limitations, in order to increase the generalizability, validity and reliability of the results obtained from these studies.