When a DOI is assigned to a resource you should include it.
For more information about DOIs, see the APA Style website:
REMEMBER: If no DOI is assigned, you must provide the URL of the journal homepage (not the URL within CINAHL or another database)
*See Chapter 7, section 7.01 for formatting examples.
All information and page number references are based on the 6th edition of the Publication Manual of the American Psychological Association (2009/10).\
Need a copy of the Publication Manual? Click here for details. See Also: APA Style Guide to Electronic References, Sixth Edition