The Manuals are the product of a collaboration between hundreds of medical experts worldwide, an independent editorial board of peer reviewers, and our editorial staff of physicians and professional medical writers. For over 100 years, we have had complete editorial independence to present the best current thinking regarding medical diagnosis and treatment, and do not in any way promote or publicize Merck or MSD products. To ensure absence of commercial or corporate bias, authors and peer reviewers cannot be employees of Merck & Co., Inc., Kenilworth, NJ, USA, nor can they serve as speakers for Merck or MSD products, or in any other way represent the company. Although the editorial staff is employed by Merck & Co., Inc., Kenilworth, NJ, USA, there is no control, review, or even input into the content of The Manuals allowed from any other part of our company, including research and development, sales and marketing, public relations, legal, and corporate management.