Nephrology Nursing Certification Review Guide c 2008 (4th edition) The 2008 edition of ANNA's Nephrology Nursing Certification Review Guide is an excellent resource to assist professionals in preparing for the Certified Nephrology Nurse (CNN) and Certified Dialysis Nurse (CDN) exams. The review guide includes comprehensive case studies and questions covering multiple areas within the specialty, a practice test answer sheet with suggested references and readings, and sections on critical thinking related to test taking. This resource can be used in conjunction with other primary sources such as ANNA's Core Curriculum for Nephrology Nursing (2008) as a study guide for the nephrology nursing certification exams.