Figure 1. Data Standardization using OMOP CDM.
Data extracted from sources with differing methods of data organization are combined with UNOS data and transformed to a common model that allows easy compilation and comparison of data from different centers for outcomes analyses. As we can see in the figure, the layout and shape that contains data are different to show the distinct structure between databases, and wordings for clinical concepts are different to show that disparate information systems represent the same clinical concepts differently. Once the disparate data sources are transformed to the OMOP CDM, the structure and clinical concept representation are standardized regardless of which data source you are dealing with. This allows institutions to apply the same analysis methods and aggregate results.