When a validation process is applied the validity of an element or attribute is expressed in an Assessment Outcome.
It is a set of properties:
[validity] - expresses whether the item is valid with values 'valid', 'invalid', or 'notKnown'.
[validation attempted] - indicates whether validation was run with values 'full' or 'none'.
[validation context] - the nearest element with a global schema declaration (this handles local declarations).
[schema specified] - indicates whether the value was defaulted by the schema with values 'infoset' or 'schema'.
It is possible that during validation some elements will be skipped as they occur in wildcarded content (e.g. xs:documentation).