Merck Manuals

The first Merck Manual was published in 1899 by Merck & Co. as a pocket-sized reference aid for doctors and pharmacists. The intended audience expanded in 1997, when the Merck Manual of Medical Information: Home Edition was added to the growing body of medical reference resources. In 2014, Merck published Merck Manuals (North America) and MSD Manuals (as it is known outside of North America) exclusively online to advance their “Global Medical Knowledge 2020” initiative to provide access to current, credible medical information to “up to three billion professionals and patients on every continent by 2020” [1]. The Merck Veterinary Manual is a separate publication that is not reviewed here.

With the relaunch, the publishers decided to offer the content of Merck Manuals completely free of charge and to translate the online offerings into ten languages. Merck Manuals is available in English and Spanish. According to publisher Melissa Adams, by the end of 2016, this list will also include Chinese, Korean, French, German, Italian, Portuguese, Russian, and Japanese [2]. Other developments in process for Merck Manuals at the time of writing include a widget that can be used on any website to connect users directly to either the consumer or professional version of the site and a free app for iOS and Android that will provide access to the entire resource.

CONTENT

Upon accessing the site, users have the option to select either the professional (“I am a medical professional or student”) or consumer (“I'm a patient, parent, or caregiver”) version of the site. This selection determines the complexity and language used, as well as the categories shown in the toolbar. Regardless of the version selected, it is easy to alternate from one to the other using links provided on every page. The versions are color-coded blue for the professional site and red for the consumer site to make it effortless to tell at a glance which version is displayed.

Both versions' landing pages feature news articles, trending topics, and interactive elements such as quiz questions, the most popular recent searches, and Merck Manual's most recent Facebook and Twitter posts. The professional version focuses on features that are useful for students and health care professionals, including case studies, commentaries, and blogs by both new and seasoned professionals. The consumer version highlights items that would appeal to patients or caregivers, such as infographics on hot topics and a first aid guide with links to the most common emergency scenarios, such as cardiac arrests, wounds, and lightning strikes.

The true value of Merck Manuals lies in the medical topic articles that formed the basis of the long-standing print editions. Medical topics primarily cover disorders but also include general information about medically related issues such as “Clinical Decision-Making Strategies” and “Benefits of Exercise.” Each article summarizes the essential things to know for each condition, written at a level of complexity best suited for the selected audience. According to Adams, articles for the consumer site are written at about an eighth-grade level and include more detail than might be found on other consumer health resources [2]. Articles are divided into an overview, etiology (“Causes” in the consumer version), pathophysiology (not included in the consumer version), symptoms and signs, diagnosis, prognosis, general treatment, and key points. If evidence-based guidelines exist for the topic in question, a link to the guideline article is included. Each article concludes with a resource list with links to tables, images, drugs, and quizzes mentioned in the article and a separate category for drugs mentioned in the article. Articles can be printed, emailed, or shared via Facebook, Twitter, LinkedIn, or Google+.

The US Food and Drug Administration requires Merck Manuals to maintain a strict separation between the publications and Merck & Co. to avoid any bias toward drugs produced by Merck. To comply with this requirement, Merck Manuals have contracted with Lexicomp Online to provide the drug information that supplements the articles. Each article lists any drugs mentioned and links to drug information that appears identical to that found in Lexicomp Online. In the professional version, this information includes not just dosage and adverse effects, but also pregnancy and lactation considerations, pricing, and possible complications for dental treatment. In the consumer version, the drug links go to patient handouts developed by Lexicomp. Other benefits of this relationship with Lexicomp include a drug interaction checker, pill identifier, and pronunciation guide.

Articles are supplemented by a number of valuable extras, such as reference guides for normal lab values, tables, graphs, animations, and videos developed by Merck Manuals showing proper exam and procedural techniques. Quizzes and case studies related to the topic allow users to interact with the material to enhance their understanding of the subject.

SITE NAVIGATION

For users looking for information on a particular condition or health area, the pervasive search bar may be the most efficient way to access the topic quickly. After searching for a condition, drug, or other keyword, users will see the first ten most-relevant articles. For searches that pull up hundreds of results, however, the search bar quickly loses its appeal. Additional results are retrieved only by clicking on “Load More,” which adds the next ten articles to the displayed list. Advanced search is not available, and users do not have the ability to sort results.

Filters located on the left side of the page allow users to narrow the search to medical topics, calculators, quizzes, or videos. The right side of the page shows related images, news items containing the keyword, and a list of the top articles from the other version of the site so that a search for hypertension from the professional site, for example, will show the top results from the consumer version (“high blood pressure”) and a link to retrieve all search results from the consumer site.

For topics that have too many results to find using the search bar, users can access content via the toolbar, which links to medical topic summaries, health news, drug information, and resources. The professional version also links to “procedures and exams” and “quizzes and cases,” while the consumer version instead includes links to “symptoms” and “emergencies.” The toolbar is also the most efficient way to directly navigate supplementary content, such as drug information or videos.

CONSIDERATIONS AND ADVANTAGES

The Merck Manuals site describes in great detail the publisher's efforts to provide unbiased and accessible medical information [2]. Articles are reviewed by an independent editorial board of medical professionals, and authors and reviewers cannot be employed by or promote Merck drugs or products from any of their subsidiaries. The site does not contain any advertisements, and readers are never asked to register or provide personal information. Authors for each article are listed along with their credentials and the dates that the article was last fully reviewed or revised. Medical topic articles are clearly differentiated from editorial commentary and news items.

As with its print predecessor, the online Merck Manuals continue to be a reliable and trusted source for medical information. The two versions are well suited to their audiences, providing a greater level of detail than might be found in other sources without the advertising and privacy concerns that accompany other free options. Merck Manuals can be recommended with confidence as a useful ready reference tool for both consumer patrons and health sciences students and professionals.