The BARNA staffing audit 2011, results and analysis can be found here.
Several useful articles on undertaking audits for quality assurance can be accessed below:
Patel S  Achieving quality assurance through clinical audit. Nursing Management. 17, 3, 28-34.
HQIP [Heathcare Quality Improvement Partnership] Criteria and indicators of best practice in clinical audit 
NAP4 [4thNational audit project of The Royal College of Anaesthetists and The Difficult Airway Society] : Major complications of airway management in the United Kingdom [March 2011] report
NCEPOD 2011 Enquiry into Patient Outcome and Death [published by the National Confidential Enquiry into Patient Outcome and Death]