PT - JOURNAL ARTICLE AU - Mary A Blegen TI - Does certification of staff nurses improve patient outcomes? AID - 10.1136/ebnurs.2011.100228 DP - 2011 Dec 01 TA - Evidence Based Nursing PG - ebnurs-2011-100228 4099 - http://ebn.bmj.com/content/early/2011/12/20/ebnurs.2011.100228.short 4100 - http://ebn.bmj.com/content/early/2011/12/20/ebnurs.2011.100228.full