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The diagrams in CDISC standards use the following coding for classification of concepts:
This classification is based on classes in the Biomedical Research Integrated Domain Group (BRIDG) model (available at http://bridgmodel.nci.nih.gov/). These color-symbol pairs have been used to highlight kinds of things that occur commonly in clinical data and therefore give rise to common patterns of data. Some concepts are not coded; they have a thinner, black outline, and no accompanying symbol. These may include the subject of an observation, as well as characteristics, or attributes, of the coded concepts.
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