US Pharm. 2010;35(1):Epub.

The Internet has evolved vastly since its precursor, ARPANET, a large wide-area network created by the United States Defense Advanced Research Project Agency (ARPA), was developed in 1969.1 Originally developed as a networking experiment, the Internet is currently being used as a health information research tool by the majority of U.S adults.1-3 One survey revealed that 61% of U.S. adults use the Web for health-related questions.3 Further, 45% of U.S. adult Internet users reported using this medium for retrieving drug information (prescription or OTC).3 The number of patients using the Internet for drug information is on the rise. Since 2002, the percentage of adult Internet users searching for drug information has increased from 34% to 45%.3 Much of the information on the Internet is unregulated; therefore, prudence is a necessity prior to making decisions based on this information. The Institute of Medicine (IOM) has stated, "The Internet is a bit like the Wild West: It has vast amounts of unregulated territory and no one in charge."4

Although 49.5% of patients indicated they preferred their physician as the initial source of health information according to the Health Information National Trends Survey (HINTS), 48.6% actually queried the Internet first.5 This observation has been validated in another survey that indicated that approximately 23% to 31% of health care providers report greater than 80% interaction with Web-informed patients.6 Furthermore, the majority of patients (>90%) believe that health care providers should be competent in directing patients to reputable sources of drug information on the Internet.7 Although many adults use the Internet for health information, the vast majority (86%) still turn to health care professionals for assistance in dealing with medical conditions.3

Health care providers should not only be competent in directing patients on Internet usage, but should also be familiar with the vast array of professional-based practice-enhancing resources available online. The key is to effectively sort through all of the available information retrieved and quickly locate reputable sources. This article reviews the evaluation process for determining the strength of information located via the Internet. Additionally, health care practitioners will be provided an overview of drug information sources available via the Internet.

Evaluating Information on the Internet

Due to the unregulated nature of the Internet, it is of utmost importance to critically evaluate information obtained by this method. Numerous instruments are available to assess the quality of information on Web sites; however, many of the instruments are difficult to use, not readily available, and contain multiple elements that make their use cumbersome.8,9 Such instruments include the Medication Website Assessment Tool (MWAT), Health On the Net (HON) Foundation Code of Conduct, and the Healthcare Website Assessment Tool (HWAT 3.0)8,10,11 The usability, reliability, and validity of the currently available instruments are unclear.12 Regardless, evaluation of information on the Internet does not necessitate an instrument. Applying several basic principles (described below) may help deduce what information is reliable.13 A tutorial aimed at evaluating Internet content is available from the National Institutes of Health (NIH).14 Although this tutorial is geared towards patients, health care practitioners may also benefit from it.

Some earlier surveys revealed that few patients actually visit Web sites recommended by their physicians; however, a more recent survey indicates that some 90% of patients believe their health care provider should direct them to health information on the Internet.7,15 Health care practitioners should not only direct patients to reputable sources of information, but should be able to provide guidance on how to evaluate them. 

Several key items should be assessed when evaluating a Web site ( TABLE 1).13 A good Web site delineates who runs the site and who is responsible for the content. This should be clearly visible on the home page or in the "About Us" section. The funding source is also important to note. If the source of funding is a company or organization that stands to profit from the content, bias may be suspected and perhaps more balanced information should be sought. The purpose of a Web site used to disperse health information should not be sales-based. The source of funding may be apparent in the suffix of the Web site address. For example, addresses ending in ".gov" are government-sponsored; those ending in ".edu" are sponsored by educational institutions; those ending in ".org" represent noncommercial organizations; and Web site addresses ending in ".com" identify commercial organizations. The top three preferred sources of health information by both patients and health care professionals are university/academic–based Web sites, consumer Web sites sponsored by medical journals or publications, and government agency Web sites.7 Relying solely on the suffixes ".gov," ".edu," and ".org," however, may not always indicate a reliable, unbiased source. Pharmaceutical manufacturer Web sites are the least preferred, followed by media-driven and commercial medical organization–driven consumer sites.7 Although manufacturer Web sites are the least preferred according to the HON 2005 survey, they often provide useful information such as drug acquisition/reimbursement instructions, medical information contacts, and current prescribing information.

Table 1. Ten Key Questions to Ask When Evaluating a Web Site

Question Comment
Who runs the Web site? Usually found in the “About Us” section. Be wary of Web sites funded by an entity that stands to profit from the message.
What is the purpose of the Web site? The primary purpose of the Web site should be educational, not financial, gain.
Who is responsible for the information? Use the suffix of the Web address as a clue (i.e., “.gov” = governmental agency, “.edu” = academic institution, etc.).
How is the information documented? References should be readily available.
What are the credentials of the contributors or reviewers? The contributors or reviewers should be health care professionals.
Is the information current? Locate the date of the last update.
What is the Web site’s linking policy? Linking should not be allowed without approval.
What is the Web site’s privacy policy? Usually found in the “Privacy” section. Information obtained from users may be sold.
Is contact information readily available? The Web site administrator is often the primary contact.
Who monitors the chat room? If a chat room is available, a moderator should be present (preferably a health care provider).

The source of content should be provided and referenced as appropriate. Additionally, documentation of the review process strengthens the credibility of information provided. Provision of the date of last update ensures that the information is current. In order to make good decisions, practitioners and patients should utilize the most current and well-established information available; therefore, assessing the presence of these criteria is crucial.

Other considerations to make note of when evaluating Web sites include linking and privacy policies. Reliable Web sites often take a more conservative approach and do not allow indiscriminate linking to their sites. Rather, they have a process or procedure in place to ensure that the entity requesting the privilege of linking is reliable. Web site user privacy may be compromised when a visitor registers or provides demographic information in exchange for content access. Prior to providing this information, one should view the privacy policy, if available. Some commercial Web sites collect information that, in turn, is sold to requesting companies. Users should be able to view the Web site’s policies and determine if providing personal information is worth gaining access to content.

Another consideration is interactions between the Web site staff and users. A "Contact Us" section should be available to site visitors in order to obtain more information regarding the site and content, to address concerns, and to ask questions. If the Web site provides chat rooms, users should be informed if a moderator is present and what the moderator’s credentials are. Be wary of information gathered in chat rooms with no moderator.

In addition to evaluating information on the Internet based on the aforementioned criteria, one should also be cognizant of several not-for-profit organizations that certify health care content on Web sites based on reliability and credibility. These certifications should reassure Web site visitors that the information contained within the site is credible. Perhaps the two most common and familiar certifications are Health of the Net Foundation’s HONcode seal of approval and Trust-e. Other certifications, accreditations, or trust mark systems include, but are not limited to, Internet Health Care coalition, MedCircle, Web Medica Acreditada, and the Utilization Review Accreditation Commission. Although these accrediting bodies exist, one survey demonstrated that only about one-half of Internet users are familiar with the most common certifications (HONcode, 41.2%; Trust-e, 56.6%).7 The appearance of the accrediting organization’s seal of approval alone does not replace critical judgment of content. Web sites must apply to obtain permission to place the respective seals of the accrediting bodies on their Web pages. To verify that the seal is legitimate, the seal should contain a hyperlink that will direct one to the accrediting body’s Web site.

Internet Search Engines

Internet search engines such as Yahoo, Google, MSN, Mamma, Dogpile, and Lycos are often utilized to search the World Wide Web. Using search engines to locate health information on the Web ranks as the third most common use of the Internet next to e-mail and product research.3,8 Among these search engines, Google is the most frequently visited.16 As with other search engines, information is quickly retrieved when a keyword is entered. The efficacy of Google in diagnosing an illness was evaluated by Tang and Ng.15 A total of 26 cases (one year’s diagnostic cases [2005] from the New England Journal of Medicine) were evaluated. The correct diagnosis was made in 15 of 26 cases (58%; 95% confidence interval, 38%-77%). This is encouraging; however, the study does not capture the incidence of incorrect diagnoses, change in time to diagnosis, and whether using Google results in unnecessary treatments and/or tests. Google Scholar, launched by Google in 2004, provides access to full-text journals, preprints, theses, books, and other "scholarly" Web pages. Similarly to its parent, Google Scholar is easily searched and also has an advanced search feature that enables users to narrow searches using keywords, author, subject, and/or publication date. Google Scholar has been compared to PubMed, Scopus, and Web of Science.17 The authors concluded that all of the databases are practical and offer several methods of searching for information. The most important advantage of Google Scholar and PubMed is open access versus the comparators. In general, Google Scholar offers results that are less accurate and less frequently updated compared to other databases. Additionally, results are displayed in relation to number of visits by users, resulting in bias towards older literature. Google Scholar does offer users the ability to locate obscure information not accessible by other databases.

Wikipedia is ranked seventh in terms of traffic on the Internet.16 Due to the popularity of Wikipedia and bias of Google towards more frequently visited Web sites, its entries are frequently listed high in search results. This is problematic, as Wikipedia is often plagued with errors of omission and the information posted is user-edited.18 Wikipedia, when compared to Medscape Drug Reference, was found to be 20% less complete (76% vs. 95.5%; P < 0.001) in terms of answering drug information questions.18 Additionally, Wikipedia did not provide adequate drug-dosing information.

In addition to serving as an accrediting body, HON provides some tools on its Web site to locate reputable information. Further, this Web site provides a search feature that only returns results that have received the HONcode seal of approval. Another search engine,, also limits results to reputable sources of health care information and leaves out advertisements and irrelevant search results.

Internet Sources of Drug Information

Primary resources: Primary resources include published meta-analyses, randomized controlled trials, observational trials, and case reports. The information obtained from this literature is the basis for evidence-based practice. The interpretation of primary resources requires the reader to be cognizant of the advantages and disadvantages of this type of information. Primary resources are generally the most up-to-date information available. Practitioners have the opportunity to review the information and form their own opinion of what the evidence supports. On the other hand, practitioners must be proficient in interpreting and evaluating the strength of medical literature. Additionally, decisions should not be based on a single piece of evidence, but rather on a compilation of all available evidence.19

With the increasing popularity of the Internet, many primary resources may be accessed directly from the Web site of the publisher or medical/pharmacy journal. Some journals may be open access; however, the majority require a subscription. Often, access to the abstract is free of charge. Due to the limited information and inherent bias provided in an abstract, it should be used to determine whether obtaining the article may be of value rather than to make a therapeutic decision.

Secondary Resources: Secondary resources direct one to primary resources. Many secondary resources such as MEDLINE/PubMed provide bibliographic and/or abstract information. There are various indexing databases available through the Internet, including Adis International, CINAHL, PubMed, OVID, Web of Science, Embase, International Pharmaceutical Abstracts, Google Scholar, Clin-Alert, and Iowa Drug Information Service. The majority of these resources require a subscription; PubMed and Google Scholar do not.

Tertiary Resources: Tertiary resources, a summary of primary resources, are abundant on the Internet. The difficulty in determining which sources to utilize often arises due to the significant amount of information retrieved following an Internet search engine query. As with print versions of tertiary resources (i.e., textbooks or review articles), online resources are only as reliable as the information they are based on. Whenever using information found on a Web site, it is critical to locate the date of the last update. This will eliminate the possibility of basing a decision on outdated evidence.

Evaluating each resource as presented earlier may be time consuming. Often, responses are needed quickly,  and this may force one to rely only on the top results presented, leading to decisions that are based on a snapshot of information. Becoming familiar with reputable sources available on the Internet will reduce search time and enhance practice. TABLE 2 summarizes select open-access Web sites providing a vast array of information. Also note that a good starting point may be the professional organization dealing with the disease/treatment information sought. For example, if information regarding the treatment of Clostridium difficile is sought, perhaps searching the Infectious Diseases Society of America Web site for a guideline would yield the most reliable results. A cautionary statement is required when utilizing this approach, however, because the appearance of a professional organization does not always equate to reliable information. When in doubt, using the aforementioned criteria to evaluate Web sites may help ensure the use of quality information.

Table 2. Select Open-Access Drug Information Sources Available Via the Internet

Web Address Sponsor Area(s) Covered Merck General medicine
National Centers for Complementary and Alternative Medicine
NIH Office of Dietary Supplements
United States Pharmacopeia
Herbal and alternative medicine
NIH MedlinePlus
Mayo Clinic

National Library of Medicine
National Council on Patient Information and Education
Patient information GlobalRPh Inc General pharmacy; calculators
National Guideline Clearinghouse
The Cochrane Collaboration
Agency for Healthcare Research and Quality
Evidence-based medicine;
only abstracts are open access at the Cochrane Collaboration National Library of Medicine General health and education; links to MedlinePlus, AIDSinfo, PubMed, and others National Institutes of Health General health and education; 27 disease/organ-specific institutes Centers for Disease Control and Prevention General health and education; traveler's health Food and Drug Administration General information on drugs and biologics; bioequivalence information (Orange Book) ArizonaCERT QT-prolonging potential of drugs Indiana University School of Medicine CYP450 interactions Unknown, maintained by a clinical pharmacist Gluten-free medications National Institutes of Health Clinical trial registry PhRMA PhRMA Clinical Study Results Database
American Society of Health System Pharmacists
American College of Clinical Pharmacy
Academy of Managed Care Pharmacy
American Pharmacists Association
Pharmacy practice resources Various hospitals and associations Health information translations
American Society of Clinical Oncology
National Comprehensive Cancer Network
American Society of Hematology
Cancer-related information Medscape General medicine Orphanet Portal for rare diseases and orphan drugs Health care information search engine


A wealth of information is available via the Internet. Information obtained from the Web must be critically evaluated prior to its use in making treatment decisions. In general, a decision should encompass multiple sources, each of which enhances and validates information obtained from the other. Applying this approach will ensure that treatment decisions are based on high-quality information, thus improving patient care. Patients should be encouraged to discuss information they obtain on the Internet with their health care providers. In addition, patients must be made aware that not all information obtained is reliable and that this information should enhance, rather than replace, the patient–health care provider relationship.


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