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Data in one file of a series is allowed to depend on definitions contained in an earlier file in the series. If a file contains either ReferenceData or ClinicalData then that file must either contain the necessary metadata definitions to interpret that data directly, or there must be a previous file in the series that contains these definitions. Similarly, if a file contains ClinicalData or ReferenceData, the file must either contain the administrative data referenced in the audit and signature records, or there must be a previous file in the series that contains that data.
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