Features - Researching Medical Literature on the Internet -- 2005 Update

Gloria Miccioli has been a law librarian for 23 years. Her specialty is research. She has worked as Government Documents/Reference Librarian at the Jacob Burns Law Library of the George Washington University Law School; as Senior Research Librarian for Williams & Connolly; and is currently International Librarian for Jones DayD.C. office, where she provides expert research services for the firm's overseas offices.


The proliferation of medical websites is good news for the researcher with a small to non-existent medical collection. Legal researchers often have to consult medical sources, so it is fortunate that the Internet provides free access to a great deal of the medical literature, either in full text or citation/abstract format, and that it offers search capabilities good enough to fulfill most information needs. In addition, public demand for medical information on the World Wide Web continues to grow. Many professionally-oriented health care sites have evolved to meet consumer needs, and consumer-oriented sites often include professional literature. Journals, dictionaries, textbooks, indexes - all can be found on the Net in growing numbers. The sources are varied; they include publishers, government agencies, professional organizations, and health libraries, to name a few.1  In addition, more and more of this information is being offered for free, which is not the trend in other subjects, particularly business and law.

With so many medical web sites to search, how does a researcher know which to choose? It depends on what you are looking for. Journal articles make up an extremely important category of the medical literature because they contain the latest research. MEDLINE, one of the jewels of medical research, is the National Library of Medicine's electronic index that provides bibliographic references to some 4800 American and foreign biomedical journals. Most records are from English-language sources or have English abstracts. The database contains over 12 million citations and dates back to the mid-1960s. As such, it is a mainstay of medical research, especially for current information. It is offered at no cost on the Internet and is accessible not only from the NLM web site but also from other sites, such as those of medical libraries and medical associations. But remember: not all MEDLINE sites are the same. Some do not cover the entire MEDLINE database; some do not offer all MEDLINE search features. Read the web site's description, if there is one, to determine exactly how much MEDLINE is offered.

MEDLINE can be searched from two National Library of Medicine websites, PubMed and NLM Gateway. These web products are both similar and different.

National Library of Medicine Databases

PubMed
PubMed is also referred to on its website as Entrez PubMed. "Entrez" refers to the date that a citation is added to the database, as opposed to the actual publication date of the article.
 
PubMed was developed by the National Center for Biotechnology Information (NCBI) at the National Library of Medicine in conjunction with publishers of medical literature. PubMed contains only the MEDLINE database plus links to NCBI's molecular biology databases. As of September 30, 2003, OLDMEDLINE citations have been incorporated into the MEDLINE database on PubMed. OLDMEDLINE contained around 1.5 million citations predating 1966, which is when MEDLINE coverage started. These earlier citations were originally printed in hard copy indexes published from 1953 through 1965. A separate search of OLDMEDLINE was required for pre-1966 literature; now that OLDMEDLINE is part of MEDLINE, a search of MEDLINE on PubMed will include these early citations. NLM will continue to add citations from older print indexes. A good overview of PubMed can be found on its website.

A wonderful trend in medical literature is the growing availability of full text information. NLM is certainly in the forefront of this trend. The problem with medical research from my point of view has been the need to get the articles once you have a list of citations or abstracts. Document retrieval has not always been easy nor has it been inexpensive. PubMed, however, provides the full text of articles of participating journals. Access to the full text depends on the publisher; some require a fee or subscription. PubMed makes it clear when a fee is required. The LinkOut feature of Entrez PubMed takes users from citations in the PubMed and Entrez databases to various web resources, such as full-text publications, consumer health information, research tools and more. You can see a list of the approximately 4,580 journals that offer full-text links as well as a list of the approximately 1545 LinkOut providers. You can also review the 573 journals that offer free full-text articles. Note: these are not complete lists of all free, full-text journals on the web, just of those that participate in the LinkOut program. In addition, the National Library of Medicine's digital archives of life sciences journal literature is available for free from PubMedCentral.
 
Along with access to full text articles, NCBI has a growing collection of biomedical textbooks available for search and retrieval. The Bookshelf home page has 36 books for the user to view and search. Or, you can select Books from the PubMed home page pull-down menu next to the search button. There are also links to these texts from PubMed abstracts and summary documents.
 
PubMed offers powerful searching and may seem somewhat complicated to the novice. I recommend that new users click on the Help screen for detailed information on PubMed or take the online Tutorial. Links are on the left sidebar of the home page. Both are easy to understand and explain the many features available to medical researchers. To search PubMed, you can enter terms in a simple query box on the PubMed home page, or you can click on Preview/Index for more advanced searches. You can also search by author and journal title. To narrow your search parameters, click on Limits and use pull-down menus to restrict the search by field (such as title, title word, abstract word, MeSH heading, issue, page number, and so on) and by language, age, gender, publication type, date range, and more. PubMed allows for Boolean searching and the use of a command language to designate search fields. 
 
Articles in MEDLINE are indexed by actual medical terms, so it is critical for the searcher to use those terms. Because not everyone who uses MEDLINE is familiar with medical vocabulary, the system is programmed to help you find precise terminology by leading you to MeSH subject headings. The National Library of Medicine has developed an extensive controlled vocabulary called Medical Subject Headings (MeSH); using MeSH terms in a search will lead to greater accuracy and relevancy in search results. You can browse through a ranked list of terms, by clicking on MeSH Database on the left sidebar of the home page. If you have not searched MeSH before, and maybe even if you have, click on the new animated tutorials for searching the MeSH Database. There are 3 excellent short tutorials that have voice narration as well as captions. Remember, PubMed was designed for medical professionals and its subject heading system is a bit confusing. Throw in the need for correct medical terminology and searching is that much harder. But NLM knows this and continues to find ways to make searching easier.
 
Here you will find MeSH terms and hierarchies and relevant co-terms. Enter a term and the system will respond with the correct MeSH heading(s), which can then be selected. When I entered "norplant", I got the MeSH heading "levornorgestrel" and a short definition, plus several related terms. To find citations with that MeSH heading, just click on Links on the right side of the term, and then click on PubMed. Clicking on levornorgestrel led me to the term hierarchy, from which more terms could be selected and added to the search. You can also designate main headings. Terms will also be automatically "exploded" unless you indicate otherwise; that is, subheadings of a term will be searched along with the main heading. I can't stress enough the importance of using the MeSH function; your results will be more accurate when you use the terms assigned to the article by the indexer. Furthermore, the non-medical searcher may not be able to guess the correct terms: how many of us know that "mad cow disease" is represented in MEDLINE as "encephalopathy, bovine spongiform"? Be aware, however, that very new citations that are still being processed may not have been assigned MeSH headings yet. Similarly, citations from OLDMEDLINE will not have MeSH headings.
 
Using a system called Automatic Term Mapping, the PubMed search engine automatically tries to match search terms, author names, and journal titles against established lists. Phrases, however, bypass ATM and are searched in the index of searchable terms, which can be viewed by clicking on Preview/Index on the home page. Search terms must be designated as a phrase in order for them to be searched as such: the searcher can use double quotes or a phrase search tag. If there is no match the terms will be ANDed together. 
 
Search results can be displayed in different formats. Initial results appear in summary format, which includes authors, title, journal, publication type, and citation status. It also displays icon links to indicate whether or not the citation includes an abstract or if the full text is available free in PubMed Central or elsewhere. In addition, PubMed allows you to retrieve related articles for most citations, because most records in MEDLINE are linked to other records by a matching algorithm. While you are on the summary results page, take a good look at the long list of items that appear on the pull-down menu next to the Display box. The choice of formats and/or links is impressive. The citation format will include MeSH terms plus an abstract, so you can select that to see what terms were assigned to an article. The abstract format is less useful because it does not include the MeSH terms. Next to each citation/abstract is a Links icon; this will take you to free or fee sources of the full text. Very old and very new articles will probably only appear as citations.
 
The LinkOut display format allows publishers, libraries, aggregators, biomedical databases, and other web resources to display links to their sites; these links may be to the full text of the article (free and fee both), to consumer information, and to other related data. Read the explanation and review a list of LinkOut providers. Once you select LinkOut and hit the Display button, your results will appear with very clearly marked links and icons that indicate full text, format (e.g. pdf), and other information. What an incredible time-saver!
 
A Send To pull-down menu on the results screen allows you to save or send search results. For example, you can e-mail them, download them, or send them to a Lonesome Doc order screen; Loansome Doc is the fee-based online ordering system of the National Library of Medicine. The user has only to point and click to order the full text of desired articles.
 
PubMed has several other useful features; links are on the homepage sidebar:
  • The Journals Database lets you look up journal names, MEDLINE abbreviations, or ISSN numbers.
  • Single Citation Matcher allows you to verify a single citation.
  • The Batch Citation Matcher allows you to verify multiple citations.
  • A Clinical Queries form is available so a user can search for the therapy, diagnosis, etiology, and prognosis of a topic.
  • My NCBI: Formerly Cubby, My NCBI is a stored search feature that allows users to store and automatically update searches. To register, click on the button and follow the instructions.
NLM Gateway

NLM Gateway is the user-friendly way to search MEDLINE and other National Library of Medicine databases. It is broader in scope than PubMed because it goes beyond journal citations to include the monographs, serials, and audiovisual materials of the NLM collection as well as the contents of several other databases in a "one-stop shopping" search and retrieval. interface. Introduced in October 2000, NLM Gateway searches its network of NLM databases simultaneously. Its target is "the Internet user who is new to NLM's online resources and does not know what information is available there or how best to search for it". A new version of Gateway was released on April 4, 2005. For a description of the new features, see the NLM Technical Bulletin of March-April 2005.

The current version of Gateway searches:
  • MEDLINE via PubMed
  • MEDLINEplus, the consumer health web site of NLM.
  • National Library of Medicine Catalog (seen as LocatorPlus on the Gateway home page).
  • TOXLINE Special
  • ClinicalTrials.gov, information about clinical research studies
  • DIRLINE, the Directory of Information Resources Online
  • Meeting Abstracts, abstracts of meetings on selected subjects

  • HSRProj., with information about ongoing grants and contracts in health services research.
  • HSDB, Hazardous Substance Data Bank available through a link on TOXNET
  • Genetics Home Reference - consumer information about genetic conditions and genes
  • OMIM, Online Mendelian Inheritance in Man - catalog of human genes

To search across databases or collections, as NLM calls them, enter a search in the search box. For example, I entered "norplant" and got a Results Summary page that divided the results by category/collection. There were 2,656 journal citations/abstracts from PubMed, 16 Meeting Abstracts, and so on. Click on a collection or database to view the results. A pull-down menu "Select an action" allows you to download/display, email, save (Put in Locker), or order documents (a link to LoansomeDoc that is only available for PubMed results). A new Sidebar on the left side of the screen links directly to the other results.

Or you can begin your query by clicking on Term Finder and then entering a term in the search box. In so doing, you can access MeSH Headings (the controlled vocabulary thesaurus) and NLM's Unified Medical Language System's Metathesaurus (which contains information about biomedical concepts and terms from many sources). Unlike PubMed, you do not have to enter phrases in quotes. If you do not want adjacent terms searched as a phrase, use Boolean operators. You can also just enter the term and click on Search or hit enter without also clicking on Find Terms. Gateway automatically selects the correct MeSH terms and searches it across all Gateway databases. It doesn't get much simpler than this.

Click on LimitsSettings to narrow your search by document category, English language, and publication year and collection/database. Note that PubMed's Limits button offered many more options. According to the Gateway Help page, searchers have to use field tags to search by age, gender, title, author, etc. However, there is no pull-down menu of these tags that I could find on the search screens; the user would have to check the Help page list of field tags and make a note of them or remember them. In my opinion, this is somewhat contrary to Gateway's goal of being user-friendly.

On the Results Summary page search results are divided into categories, another nice feature. To see the terms for each database, you can click on Search Details on the top of the Results Summary page. Although I only entered the term norplant, levornorgestrel was also searched. Below the citation or abstract are links to related articles and to LinkOut, which gives a publisher link if it exists. The Locker stores selected search results and now includes an item count. The Locker requires free registration. The History button displays the most recent 25 search statements and allows you to combine them.

NLM Gateway is easy to use and allows for simultaneous searching of several medical databases and of different types of medical literature. It is a good first step for researchers. Those who need more powerful search features for journal literature should turn directly to PubMed.

PubMed and Gateway are wonderful resources for medical researchers and they are free. They do take a bit of practice, at least for me. Maneuvering among the MeSH browser, pull-down menus, and various fields - i.e., defining and modifying the query - can be a little confusing. However, upgrades have made these systems easier to use, and no doubt this will continue. With practice, the user will find that PubMed and Gateway are excellent vehicles with which to retrieve medical information.

As a final note, please be advised of this important FAQ Retired Databases, updated May 12. 2005, which lists the NLM products that no longer exist, and provides links to alternative, related sources.

 

MEDLINEplus

Before we leave NIH, let me mention MEDLINEPlus, NLM's effort to provide consumer-oriented medical information. Launched in the fall of 1998, this system is easy to use and understand. Sources include medical dictionaries, a medical encyclopedia, provider directories, health news, and access to health-related government and non-government databases, including a link to PubMed for MEDLINE searching. It is updated daily, and is a good place to get basic information on a disease, medical condition or treatment, or a drug; you can then turn to the medical literature for more sophisticated information. A site map details and organizes the many sources of information.
 
MedlinePlus was ranked as the top Information/News web site on the American Customer Satisfaction Index of U.S. federal government web sites (December 2004).

To stay current on the many improvements and changes made to the NLM databases, turn to the NLM Technical Bulletins for regular updates.

If MEDLINE is available in not one, but two, formats from NLM, why would a researcher choose to search it on a non-NLM website? One reason is convenience, especially if the user is already on another medical site that links to MEDLINE. Often the link is to PubMed. A more compelling reason is that some sites offer MEDLINE searching with a little extra added.
 

Commercial Web Sites

Medscape
One such site is Medscape, part of the WebMD Corporation. Its goal is to provide medical professionals with an integrated web product. The site offers MEDLINE searching, but it also contains information from texts, news providers, medical education programs, and materials created specifically for Medscape, including a collection of articles with a clinical focus. Thus its real value is not so much access to MEDLINE as it is access to these additional sources of information. Like many medical web sites, Medscape requires a free, one-time registration, after which the user can create a personal home page that focuses on his or her medical specialty. However, the web site is pretty confusing. Details on what is covered are few; navigation involves too much trial and error. An About Medscape button, buried on the bottom of the home page, leads to a brief description of Medscape content: "Physician Optimized MEDLINE" (this is not explained here), CME materials, conference coverage, current medical news, journals and textbooks, and the Internet's first primary-source medical journal, Medscape General Medicine. There's more…the page says so…but it does not tell you what it is. The Advanced Search button goes to a search page where you can select to search Medscape, Medline, or DrugInfo. Under "Limit your search to any of the following" was a button for Medscape Select. Clicking on those words finally brought an explanation of one MEDLINE enhancement: Medscape Select consists of a core collection of 269 English-language only MEDLINE journals that have been selected by Medscape editors as the most valuable journals for clinicians. You can limit your search to just these journals. This is a great tool, but it should be a little easier to find out about it.
 
Another difference in Medscape's MEDLINE is the searching itself. Medscape has designed its own search screens instead of defaulting to PubMed. The basic search screen is a simple query box on the right sidebar of the home page or on the bottom of every Medscape page. The advanced screen accepts either natural language queries or Boolean searching. You can search by author and journal and limit searches to English, date, and a number of other fields found in a pull-down menu. You can also select to have your query searched by "concept mapping", i.e., the automatic selection of correct medical terms, and to have variant terms searched.

Another way to approach Medscape is by subject. Medscape has organized its information by medical specialties, each with its own home page. Click on the Medical Specialties button at the top of any page for a list of the medical specialties and links to different kinds of medical information on each specialty.

Also on the top of the Medscape screen is a button to Medscape Today, which is subdivided into different categories of recent medical information, such as CME News. Resource Centers covers regularly updated collections of key clinical content and is arranged by subject.
 
Medscape is to be applauded for its comprehensive approach to medical information and for the fact that it is free. While it is easier to understand and use than at my last review, the lack of details is frustrating and leads to a lot of trial and error clicking. There is so much content that some kind of overall site map and help screen are needed or the value of the site is diminished.
MedicineNet.com
When I do medical research, I usually try to find a plain English description of the topic before I start to search MEDLINE - and sometimes after. MedicineNet.com is a good place to go for understandable yet in-depth medical information. Produced by a network of U.S. board certified physician-writers, this site has hundreds of web articles on diseases, treatments, procedures, tests, and drugs. And it has a Site Map. There is a simple query box, or you can click on one of the following categories: Diseases and Conditions, Procedures and Tests, Medications, and MedTerms Dictionary. Each category has an A to Z list of terms, or you can enter a term in a search box. The Home Page also features a links to information on focused topics, for example, allergies. There are also links to other e-publications, such as health newsletters.
 
eMedicine.com
Launched in 1996 as a privately held company, eMedicine.com's goal is to provide quality medical literature for healthcare professionals. Nearly 10,000 physician authors and editors contribute to the eMedicine Clinical Knowledge Base, which contains articles on 7,000 diseases and disorders. It provides the latest practice guidelines in 62 medical specialties. eMedicine content undergoes 4 levels of peer review to ensure quality. In addition to textual information, there is also a collection of medical images. Basic and advanced searching are available. I entered "anxiety" as a simple search and got 100 hits, which were arranged by title. Also given were the medical specialty (e.g., pediatrics) and the date of the latest update. In addition, the search resulted in small images - five charts and nine CME sources in the form of references to books. (Enlarged images are only available to paid subscribers.) The advanced search allowed me to limit searches by specialty and document type and to use Boolean operators. Accessing the full text required free registration. Under Tools/Resources on the left sidebar are links to MEDLINE, journals, and other resources. A sister site, http://www.emedicinehealth.com/, contains 5500 pages of health information written by physicians for consumers and patients.
 
Aetna InteliHealth
Another site that seeks to make health care information accessible to a wide audience is Aetna InteliHealth, a subsidiary of Aetna. It seeks to provide "credible information and useful tools from the most trusted sources, including Harvard Medical School and the University of Pennsylvania School of Dental and Oral Surgery." Health information developed by InteliHealth is reviewed and approved by medical experts. Over 150 health care organizations, including NIH, are contributors. A Help button (again buried on the bottom of the home page) leads to easily understandable tips for searching. On the home page are two search boxes, one for Drug Names and one for Search Terms. Entering a drug name links to information found on SafeMedication.com a site produced by the American Society of Health System Pharmacists. This site includes pronunciation guides for drugs; what a useful tool!

Entering search terms results in short articles and questions from consumers that are answered by experts. You can also click on the home page category Diseases and Conditions for an alphabetical list of topics. Look It Up links to a page of different health resources, including a medical dictionary, information on conditions, tests and procedures, the Drug Resource Center and a link to Search Medical Literature . This takes the user to TopicDoc, a user-friendly medical literature service that offers a topic-driven approach to MEDLINE. TopicDoc (formerly MedCite) consists of the search results for over 15,000 topics that have been searched by medical research librarians from the Johns Hopkins health science centers. Citations or abstracts to the 50 best articles are immediately accessible for each topic. All TopicDoc searches are updated and document delivery is available. If your topic is covered, it's like having a medical librarian on hand. TopicDoc requires free registration.
Medical Matrix
Formerly a free site from a nonprofit organization, Medical Matrix started requiring subscriptions in 2002. An individual can subscribe for $99 per year or $14 per month; an institutional subscription for up to 5 users costs $599 (up from $249 in 2003). Its goal is to be the "largest peer-reviewed directory" of medical web sites on the Internet. Because I do not subscribe and because there is little information on what is now covered, I could not evaluate this web site as it exists today. However, a sample search from the Take a Tour button shows that Medical Matrix still annotates and evaluates different categories of medical web sites, including news sites, patient information sites, medical image sites, and sites on medical education and drugs. It also links to them. I have tried to include only free web sites in this review; however, Medical Matrix may be worth a trial since it does what it does very well.
Drugs.com
The free information on prescription and over-the-counter drugs that is found on Drugs.com is supplied by three independent medical information suppliers, Physicians' Desk Reference, Cerner Multum and Thomson Micromedex. It is not affiliated with any pharmaceutical companies. This is a great site with lots of information. By selecting a drug from the alphabetical list or by entering a name in a search box, you will get information divided into categories, such as basic and advanced consumer information, the entry from the Physician's Desk Reference (access to this requires free registration on the Drugs.com site), and news and related articles.

What truly is outstanding about this site is that it allows you to search by medical condition, drug interactions, and visual images of drugs. The Pill Identifier lets you use pull-down menus to enter a description of a drug. It responds with the names and pictures of pills that fit that description. Conversely, you can click on Images to enter the name of a drug and get an image of it. However, although this is very useful and also fun to use, it does not always work. For example, the database has images of "Tylenol" but not of "Advil."
PDRhealth
The layman's version of the Physicians' Desk Reference can be found on this site, which is produced by Thomson Healthcare. The drug information here is written in plain English and is not as detailed, but it does display images. It covers prescription drugs, over-the-counter drugs, nutritional supplements, and herbal medicines. The physician's version of the PDR is found at PDR.net, which requires a purchase by anyone who is not a healthcare professional.

<Table of Contents>

Libraries and Nonprofit Organizations

MedWeb@Emory University
As they have with all types of information, librarians have helped to make medical information more available and easier to search. MedWeb is a catalog of biomedical and health sites maintained by the staff of Emory University's Health Sciences Library. One impressive feature is its links to health-related sites located around the world (click on Institutions on the home page). You can also search this by location. It also has links to a great deal of medical information. For example, if you click on Subject Index on the left sidebar, you will be taken to a long list of medical subjects. Browse and select for relevant links. Medical libraries brings up 280 links to medical libraries around the world. MEDLINE links to various sites that offer MEDLINE searching as well as information about searching MEDLINE. You can limit each subject link by clicking on Focus further. Back on the homepage, the button Publications links to numerous e-publications, including journals, texts, practice guidelines, databases, directories, and encyclopedias. Some are free; some are fee-based. There is also a search box for keyword searching.
Medical/Health Sciences Libraries on the Web
Hospitals, medical libraries, and professional associations that have a presence on the Web often provide links to sites that reproduce or index medical literature. In addition, the online catalogs of medical libraries are a window to the world of medical publishing. Medical/Health Sciences Libraries on the Web links to academic, hospital, and military medical libraries and many other medical sites in the U.S. and around the world. The home page also has a link to a selected list of free full-text online electronic medical journals (click on Free Medical Journals on the top of the page). In addition, this site, produced by the University of Iowa Hardin Library for the Health Sciences, compiles the Hardin Meta Directory of Internet Health Sources, a directory of what it considers to be the best health-related sites on the web. They are arranged by medical specialty. 
Medical Society of Virginia
The Medical Society of Virginia is good example of a medical association that compiles links to regional medical resources on its website. Click on Links & Resources on the sidebar to see a page of links of Virginia-based health care sites, including state and local agencies, Virginia medical schools, and nonprofit organizations.
HealthWeb
HealthWeb has links to evaluated, non-commercial, health-related resources on the World Wide Web that are selected by librarians and information professionals at over 20 leading academic medical centers in the Midwest. Selection stresses quality and the content is directed toward both health care professionals and consumers. Using a no-frills approach, HealthWeb's home page is simply a list of medical subjects that you can click on for an annotated list of links to web sites on that subject. For example, clicking on Psychiatry/Psychology yields annotated links to 10 web sites. There are also simple and advanced search screens.
Public Library of Science
Just as electronic information and the Internet have changed the very nature of legal publishing, they are also having a profound effect on medical and scientific publishing. The Public Library of Science is a non-profit organization of scientists and physicians committed to free and timely online access to the world's scientific and medical literature. It has just issued the first issue of its first online journal, PLoSBiology. A second journal called PLoS Medicine was launched in October 2004. Three more journals are planned for 2005. These journals will be funded by authors and participating institutions, which does away with the need for increasingly expensive subscriptions by users and thus makes research accessible to "even the poorest of graduate students." It also is intended to speed up the pace at which research is published and eliminate the control now held by journals on scientific publishing.2 Standards of quality will be retained. To ensure further access to the articles, the full contents of every issue will be placed in PubMedCentral, the National Library of Medicine's collection of free, full text articles.

<Table of Contents>

Journals and Textbooks

FreeMedicalJournals.com & FreeBooks4Doctors.com
 
For direct access to the current issues of 1400 free, full-text medical journals, go to FreeMedicalJournals.com. This site is somewhat mysterious; there is very little about the producers. But its goal is admirable: to promote the free availability of full text medical journals on the Web. The journals are sorted alphabetically and by specialty, and cover both English-language and non-English publications. FreeBooks4Doctors is a sister site that links to the full text of 650 medical texts. They are arranged by specialty or title and language. This site also links to AMEDEO, a current awareness resource. For journal alerts, you can enter a topic, select some journals and you will receive weekly e-mail news updates with overviews of the new articles that have been published in the journals subset you have created as well as abstracts of the articles in your journal subset. To get news of new books, link to AMEDEO's book alert service on the FreeBooks home page and create a profile.
Directory of Open Access Journals
This directory of free, full-text, quality-controlled scientific and scholarly journals aims to cover all subjects and languages and therefore is a valuable guide to foreign-language medical journals. As of this writing, the directory covers 1440 journals, with 351 titles being searchable at the article level. In other words, you cannot find citations to articles for every journal listed, nor can you find the full text of those citations. There are over 63,000 articles available, however.

Hosted by the Lund University Libraries in Sweden, DOAJ is funded by the Open Society Institute - Budapest and is supported by the Scholarly Publishing and Academic Resources Coalition. It represents a truly international effort to bring free content to the Internet.
The searcher has several options. The home page has a search box, a list of journal titles by category (including Biological and Life Sciences and Health Sciences), and an alphabetical list of titles. Results will give bibliographic information and language(s) of the journal and will state whether content is available. You can also search the available articles directly by clicking on Search Articles on the sidebar. For example, the entry for Japanese Journal of Complementary and Alternative Medicine told me that the text was in Japanese and English; it also linked to available issues and to the publisher.
PubMed Central
As mentioned above, PubMed Central is the National Library of Medicine's free database of full-text medical articles. Starting in 2004, NLM began to work with the Wellcome Trust and the U.K. Joint Information Systems Committee to digitize the complete backfiles of a number of important and historically significant medical journals. The content will be made freely available on the Internet via PubMed Central.
 
FindArticles
FindArticles.com is a search engine for periodical articles from over 900 publications, including medical and health titles. Although some of the content is available only for a fee, the full text of many articles is free. The frustrating thing about this web site is the lack of detail about what is covered. Searching is easy. Hit Medical Research on the home page and search by category or use the simple search box. Results can be sorted by relevance, date, length (a nice feature) and by title of the publication. When I entered "anxiety" as a simple search, I got 1,993 results. The default listing is by relevance, which is a good thing, because when I looked at the results, I saw some that were pretty irrelevant. For example, there was a 1984 article from Discount & Store News about ordering sheets; apparently some problems were causing anxiety for store employees. The other interesting thing is that according to the brief description of FindArticles that I found, articles in the database date from 1998. But many articles in my search results were dated before that. So sort by relevance and you should be okay.

The advanced search option helped to get better results; you can search by words in the title, by publication, by date, and by the number of pages. An advanced search on "anxiety" as a title word brought up 581 articles.
 
Internet Medical Bookstore
Often researchers will need to consult medical texts. First, however, they must be identified and obtained. For information about print and electronic products that are available for sale, visit the Internet Medical Bookstore. I could not determine the number of items available today, but in 2003, over 75,000 items could be ordered online. Click on Browse to search by subject matter. To search by author, title, ISBN, category, year of publication, or price, hit the Search Databases option and select either simple search or hit Advanced Search.
 
Merck Manual of Diagnosis and Therapy
A standard medical reference text, the Merck Manual is available free for searching on the Web. Select topics from the Table of Contents or perform a basic or advanced keyword search.

<Table of Contents>

Medical Search Engines and Visual Information

Scirus
Scirus is a science-specific search engine that searches over 167 million web pages while it filters out non-scientific web sites. It covers scientific, scholarly, technical, and medical data from reports, peer-reviewed articles, and journals, including pages often invisible to other search engines. The simple search box allows you to search journals, web resources or both. Entering "Cox-2 inhibitors" as a phrase resulted in 2,649 journal articles and 8,325 web resources. Scirus lists suggested terms for narrowing the search on the right sidebar. An advanced search screen allows you to limit by date, information type, file formats (PDF or html or both), source (such as MEDLINE), and subject. It is very easy to use.
 
MedNets
Ranked 4th out of 95 medical directories by the Google Directory3, MedNets has gathered over 20,000 health care links in MedExplore, its medical professional and patient health care information directory. Since my last review, the site has improved in describing what is covered and how it works, but there is still not much about the producer. Even more important, to use it as a meta-search engine, the user must register…but I could not figure out how to do this. When you enter a search in the Medetective box the only result you will get is a statement extolling the benefits of registering. However, after clicking on everything I could find, I still did not see a way to register. It might be there, but it's not easy to find. According to its intro, MedNets was designed to be easy to read and navigate; it does not entirely succeed.

You can see a list of links to searchable databases by hitting Searchable Databases on the sidebar. The National Library of Medicine is one of them. Also on the sidebar are links to internal medicine journals, associations and societies, news sources and books for sale on Amazon.com. All sources are international in scope. 
MedBot
Another medical search engine that I would like to mention is MedBot by Stanford University. MedBot brings together several types of resources: general search engines, medical indices, news sites, medical education, and medical imaging and multimedia sites. Some of these resources can be combined for a single Super Search; the user selects up to 4 databases to be searched at one time. Or, you can click on each category and search the listed sites one at a time. MedBot is easy to use and gives good results.  Some of the search engines listed no longer exist or have broken links.

The button marked Medical Images and Multimedia underscores the fact that the research of medical sources is often a hunt for visual information. The fact that the Internet is not restricted to textual medical information makes it an extremely valuable research tool. Clicking on that button on the left sidebar brings up query boxes for:
  • WebPath, an electronic collection of 1900 images of pathology specimens along with text, tutorials, laboratory exercises, and examination items.
  • PathAtlas, which contains pathological images that are categorized by subject.

 

OmniMedicalSearch
Like MedBot, OmniMedicalSearch is another medical metasearch engine. It is also another mysterious site in terms of its producer. It is "founded and owned by a private individual" who is named but whose qualifications are not given. Nevertheless, it is well designed and seems easy to use. OmniMedicalSearches up to 32 sources; each is "non-commercial and an established authority for delivering responsible medical information". They include PubMed and MedlinePlus. The home page is very simple: a search box and pull-down menus of sources to select for searching and how to search the terms. You can search all or some of the sources. You can also select Medpro, which searches 15 sources with a target audience of medical professionals. Basic Search will search 8 sources aimed at the public. When I entered "anxiety", I got 89 results, with separate links to available images and recent news. Results will offer a list of related terms with which to modify your search. Also, the results summary highlights your search terms in yellow; click on it to be taken to a number of definitions from OneLook.com.

I suggest looking at the Overview and the Site Map before starting; they have explanations and links to other features, such as an Acronym Search Engine. The features are useful and would be better placed on the home page.

The Medical Image MetaSearch searches images from 7 databases. When you click on a thumbnail image, it takes you to the source of the image, plus any accompanying text.
 

Additional Sources of Visual Information

Medscape also has compiled a file of medical images. Click on Advanced Search near the search box, then on Medscape Professional. The resulting search screen allows you to select images from the Content Type pull-down menu. Entering "cyst" resulted in 57 images. Expand an image by clicking on it; you will also get a caption that gives the source for that image.

Researchers can search a FindLaw database of over 10,000 medical images. The illustrations were developed for legal matters, such as medical malpractice exhibits. This is a truly outstanding resource: it is comprehensive and easy to use. Enter a term in the query box or select lists arranged by body part, medical specialty, and medical topic. Selecting "kneecaps" brings up 353 images from different categories, such as anatomical models and medical exhibits. You can also search by category. Clicking on an image enlarges it. Downloading the image, however, incurs a fee.

Medical Images on the Web, produced by the McGoogan Library of Medicine of the University of Nebraska Medical Center, has annotated links to 31 web sites of visual medical information.

Hardin Md - Medical Pictures/Disease Pictures gathers links to a huge number of medical images; the arrangement is by subject.

Physician Information

Researchers often need information on medical providers as well as on medical conditions. Licensing data and educational background are usually available from the provider's state medical board or licensing agency. The State Board Directory website is a directory of state medical boards with links to most of the boards' web sites. The Federation of State Medical Boards is made up of 70 medical licensing authorities in the 50 states, the District of Columbia, Guam, Puerto Rico, the Northern Mariana Islands and the US Virgin Islands; the FSMB's website links to these organizations. To find out if a doctor is board-certified, go to the web site of the American Board of Medical Specialties. Once you register for free use, you can login and search by name and location or specialty and location.

While it is not that difficult to determine if a physician is licensed, the lack of information about whether he or she has ever been disciplined is a growing concern. Part of the problem is that the availability of this information varies from state to state. But here, as with every area of information, the Internet is making a difference. The watchdog group Public Citizen publishes a survey of the quality of information found on state Medical Board web sites. Of the 50 state boards that regulate medical doctors and that of the District of Columbia, all have websites. Most name disciplined doctors. Since the kind of disciplinary information on these web sites varies from state to state, Public Citizen graded them for their quality. Only 7 states, including Maryland and Virginia, got an "A" for the quality of its content. The sites were also graded by ease of use. An overview of the survey and detailed results are available. There are also links to each state board's website.

In 2004, Public Citizen ranked the performance of the state medical boards based on the rate of serious disciplinary actions taken against doctors in 2003. Rhode Island's performance was ranked worst, while Kentucky's was the best. Read a summary and see the report.

If you are not satisfied with what you can find for free with regard to disciplinary actions against doctors, you can use Docinfo.org, which was launched in early 2001 by the aforementioned Federation of State Medical Boards. The Data Center lists state board charges against doctors dating back to the 1960s, although some information goes back to the 1940s. The site covers only U.S. medical licensed physicians, osteopathic physicians and physician assistants. To be included in the database, a disciplinary action must be a matter of public record or be legally releasable; there is no information on malpractice claims or settlements. The database, which is updated monthly and quarterly, costs $9.95 per search, whether an action is found or not. Users will learn whether action was taken, what type of action (e.g., license revocation), and the date and reason for the action.

Another Public Citizen website that names questionable doctors is named, appropriately, Questionable Doctors, but it is no longer accepting subscribers and is no longer being updated. Sponsored by Public Citizen, it is a database of doctors in 42 states who have been disciplined by state medical boards and federal agencies in the past ten years. According to the introduction, "It contains data on actions taken for medical incompetence, misprescribing drugs, sexual misconduct, criminal convictions, ethical lapses and other offenses". Searching required free registration and resulted in brief information. A subscription yielded a copy of the full report on the doctor. Users who have already registered can continue to use the site, but new users are out of luck.

Researchers may need information on organizations as well as on individuals. The Joint Commission on Accreditation of Healthcare Organizations evaluates and accredits over 15,000 healthcare organizations and programs in the United States, including hospitals, nursing homes, and laboratory services. If you want to see what entities have been accredited in a particular geographic location or to see if a particular organization is accredited, go to its Quality Check page. This is a very easy-to-use site that rewards the searcher with useful, current information.

Another source for hospital information is the American Hospital Directory. Basic information (address, web link, number of beds, etc.) is available for free. Subscribers get more detailed information, including costs and charges, financial reports, specialties, and outpatient and inpatient information. A single user pays $395 for unlimited access; there are discounts for multiple users.

Blogs

Medical blogs, known as medlogs, have invaded the Internet. I am only going to mention one, Medical News Feeds, a medlog aggregator. A long list with links to other medlogs appears on the left sidebar; take a look.

Conclusion

The Internet has become an important source of information in medicine and the health sciences, as it has in so many other areas. Medical information professionals are at the forefront of the effort to organize this vast, ever-increasing store of knowledge. The sites mentioned above reflect this effort and are meant to be a sampling of the marvelous tools that are now available to the medical researcher. Take some time to explore medicine on the Web; no doubt you'll discover many more.

<Table of Contents>

Footnotes

1 I am going to review a selected group of websites. For a more comprehensive, annotated guide to electronic and print medical resources, please see Medical Resources for Non-Medical Librarians, by Lynne M. Fox, Information and Outreach Librarian, Denison Memorial Library, University of Colorado Health Sciences Center.  <back to text>
2 An editorial in the first issue explains the PLoS philosophy and methodology in detail Why PLoS Became a Publisher, 1 PLoS Biology, no. 1, October 13, 2003.  <back to text>
3 The National Library of Medicine's MedlinePlus ranked number 1.  <back to text>