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If any of the active "from" date columns contains a value, the SUT must recognize consider the medication as active for the following periods: for every "from" column date (inclusive) until next "to" column date (inclusive). If the "to" column is empty, the medication is supposed to always remain active.
If none of the active "from" date contains a value, the application must not recognize consider the medication as active at any moment in time.
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