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The Description element must be provided and should include a prose description. The MethodSignature element must also be provided and identifies the input parameter and return values for the ConditionDef. The MethodSignature ReturnValue for ConditionDef must always equal boolean. The Description and MethodSignature are the normative content of the ConditionDef. The ConditionDef is referenced by the CollectionExceptionConditionOID attribute within a study metadata component which may be omitted under circumstances defined by the condition , (i.e., when the FormalExpression evaluates to True).
If a FormalExpression is provided, it must contain a machine-readable expression that will evaluate to True or False. Multiple FormalExpressions can be provided if each has a different Context attribute, allowing the same expression to be represented in forms appropriate to multiple systems.
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