The authors have checked with sources believed to be reliable in their efforts to provide information that is complete and in accord with generally accepted standards. However, in view of the possibility of human error or changes in medical science, neither the authors or the Cleveland Clinic Foundation nor any other party who has been involved in the preparation or publication of this work warrants that the information contained herein is in every respect accurate or complete, and they are not responsible for any errors or omissions or for the results obtained from the use of such information. Readers are encouraged to confirm the information contained herein with other sources.

