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Common Data Elements (CDEs) are standardised, precisely defined question paired with specific allowable responses. These CDEs can be used systematically across different sites, studies, or clinical trials to ensure consistent data collection [NIH]. These CDEs can be annotated with an ontological model to define their meaning and facilitate integration of CDEs from different registries [De Novo]. The ontological model is essential for computers to assess that common data elements are indeed common [De Novo].
By openly publishing the CDEs and the ontologies to annotate them openly, they can be reused to build case report forms for data collection [De Novo]. See the Register record level metadata step?
Working Group
Why is this step important
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