Beyond ACP Journal Club: how to harness MEDLINE to solve clinical problems
ACP J Club. 1994 Mar-April;120:A10-2. doi:10.7326/ACPJC-1994-120-2-A10
Related Content in the Archives
• Editorial: Beyond ACP Journal Club: how to harness MEDLINE for therapy problems
• Editorial: Beyond ACP Journal Club: how to harness MEDLINE for diagnostic problems
• Editorial: Beyond ACP Journal Club: how to harness MEDLINE for etiology problems
ACP Journal Club is designed for “current awareness,” alerting clinicians to studies important to the practice of internal medicine. The complement to current awareness is problem solving, tracking down the best current evidence to manage clinical problems that arise when seeing patients. ACP Journal Club cannot be used easily at present for this task because of its print format, limited indexing, and the short time since Journal Club began publication in 1991. An electronic version of ACP Journal Club will probably be available within a year and will overcome some of these limitations.
At present, MEDLINE is the best single service that we know of to look up current published evidence for problem solving in internal medicine. In a series of editorials beginning with this issue, we briefly describe some alternatives to MEDLINE, how to get access to MEDLINE yourself, and how to use MEDLINE effectively to retrieve the best original studies and reviews of treatments, diagnostic tests, prognostic features, and causal or risk factors. You can use MEDLINE by yourself with a little instruction and practice. Even if you do not intend to set up access to MEDLINE on your own computer, this series will help you to work with librarians to find what you need.
Traditional Sources of Information for Solving Clinical Problems
A classic study by Covell and colleagues (1) showed that internists say that they often use journals, textbooks, and other print materials to find the answers to clinical questions. This study, however, also found that, under direct observation, most clinical questions arising in ambulatory clinical practice in internal medicine go unanswered, and most questions for which an answer is actually sought go to colleagues. Further, a study on an internal medicine hospital ward found that about 5 questions arose for each patient, about 1 of which could be answered by consulting a source such as MEDLINE (2). Unfortunately, another study showed that actual MEDLINE use was only about once per week even though it was available free of charge (3). Covell's study and one by Williamson and colleagues (4) provided some reasons for this separation of promise from practice: Physicians knew that their journals were poorly organized and that their textbooks were outdated, and they felt overwhelmed by the medical literature. On the other hand, a recent study showed that clinicians quickly learned to search the medical literature themselves to the level of competence of a trained librarian for retrieval of relevant citations (5).
In its raw form, the medical literature is undeniably daunting, and traditional textbooks are at least partly out of date even as they roll off the printing presses (not that most clinicians are particularly conscientious about replacing them when new editions come out!), so consulting colleagues may be the best approach. But what if colleagues are out of date or unavailable...or wrong! And what about the questions one never gets around to answering? Fortunately, not only is electronic access to the medical literature feasible, but improvements in indexing and searching techniques make it an attractive complement to traditional information sources for clinical practice.
The Modern Textbook of Medicine
To put electronic access to the medical literature in perspective, we begin by comparing it with the most ubiquitous print source of medical information, the textbook. Most textbooks of medicine are published on a 2- to 4-year cycle. Considering that it takes about 1 year to publication from the time that a chapter is penned by its author, a sizable amount of the content is stale before the text has even gone to press. For example, 4 years after the publication of a review of 33 randomized trials by Yusuf and colleagues (6) clearly showing the value of thrombolytic therapy, a new version of a prominent medical text still claimed that the benefits of thrombolysis were not established (7). Similarly, clinicians still using the 12th edition of Harrison's Principles of Internal Medicine (8), published in 1991, will find little information of clinical use on the management of Helicobacter pylori-related dyspeptic disorders, although positive trials began appearing in the 1980s (9). Textbooks are valuable and convenient sources of much information for clinical practice, but they cannot be trusted to be accurate or current for something as important and quickly advancing as therapeutics.
Scientific American Medicine (SAM) (10) partly solves this problem by frequently updating sections during each year, with key updates driven by new evidence that is referenced in the text and often described clearly enough to permit the reader to do at least rudimentary critical appraisal. These 2 features - frequent refurbishing and citation of evidence - put SAM far ahead of the competition for general medical texts as far as we are concerned. Of course, the cost is higher than for traditional texts and one has the additional aggravation of replacing pages with the updates, but the CD-ROM version gets around this. If you do not already have a computer with a compact disc drive, the time is ripe. You can get not only SAM on CD-ROM but also an increasing number of other textbooks. More important, MEDLINE (including clinically relevant journal subsets) and several leading full-text journals, including Annals of Internal Medicine, British Medical Journal, The Journal of the American Medical Association, The Lancet, and The New England Journal of Medicine, are available online and on CD-ROM.
No matter what textbook equivalents are available in print or on electronic media, consulting the current medical literature through MEDLINE has many advantages, including timeliness, comprehensiveness, and direct connection with the original source from which all the other evidence-based information resources stem. Of course, there are disadvantages too, including time, cost, and the need to retrieve and synthesize the evidence. We devote the rest of this article and several articles in the rest of this series to MEDLINE, including tactics and tricks to maximize the yield and minimize the cost (in dollars and aggravation).
What Is MEDLINE?
MEDLINE covers all areas of medicine, goes back to 1966, is updated weekly, indexes over 4000 journals, includes over 7 000 000 articles, and provides increasingly useful “methods” indexing terms that help users retrieve the articles that are both scientifically sound and clinically relevant. Here are some options for MEDLINE access and how you can obtain it (if you do not already have it).
To search MEDLINE yourself, you need a personal computer (preferably 486 or equivalent) and a modem (preferably 2400 baud or faster) or a CD-ROM drive (preferably double-speed). MEDLINE products are available for both Macintosh and PCs, and those that we are aware of are listed in the table.
Table 1. CD-ROM Vendors and Systems
|CD Plus||CD Plus|
|333 Seventh Avenue, 6th Floor|
|New York, NY 10001|
|SilverPlatter Information, Inc.||SilverPlatter|
|1 Newton Executive Park||(unabridged and subset)|
|Newton Lower Falls, MA 02162-1449|
|EBSCO Electronic Information||EBSCO CD-ROM|
|461 Boston Road, Unit 3D||(unabridged and subset)|
|Topsfield, MA 01983|
|Healthcare Information Services||BiblioMed|
|2335 American River Road, Suite 307|
|Sacramento, CA 95825|
|DIALOG Information Services, Inc.||DIALOG OnDisc|
|3460 Hillview Avenue||(unabridged and subset)|
|Palo Alto, CA 94304|
|Aries Systems Corporation||Aries Knowledge Finder|
|1 Dundee Park||(monthly, quarterly,|
|Andover, MA 01810||and subset)|
All systems have the same core MEDLINE database, prepared by the National Library of Medicine (NLM), but the systems do have some special features. We cover a few of the basic details here. First, if you are able to conveniently share access with at least 5 colleagues, a CD-ROM system makes sense because the annual subscription fee works out to be cost-effective compared with charges for online searching if divided among 5 or more regular users. Otherwise, it is likely less expensive to use an online system, particularly one that has no monthly charge (e.g., NLM MEDLINE or PaperChase). Second, if you have a Macintosh, most online routes to MEDLINE are accessible but only 2 CD systems are, namely, Aries Knowledge Finder and SilverPlatter. Third, the American College of Physicians has negotiated a flat-rate program with the NLM. For an annual fee of $200, ACP members get Grateful Med software (for PC or Macintosh) and unlimited no-charge searching for 12 months. (Canadian members must pay an additional minimal hourly connect charge, but the program is still economical for them if they search more than once per week. For details of the program and sign-up forms, call NLM at 800-638-8490.)
All MEDLINE systems come with basic instructions for searching and most medical libraries and MEDLINE vendors, including the NLM, also offer training courses. If you are not already an independent MEDLINE user, we highly recommend that you get set up for MEDLINE searching. The table below lists the vendors and their addresses. A colleague who already uses MEDLINE, or your local medical librarian, can assist with the details if you need any help. The next editorial in the series discusses special methods for finding articles on treatments.
Table 2. Online System Vendors and Products
|National Library of Medicine||NLM Direct; GRATEFUL|
|8600 Rockville Pike||MED (PC and Macintosh)|
|Bethesda, MD 20892|
|BRS Information Technologies||BRS; BRS After Dark;|
|8000 Westpark Drive||BRS Colleague|
|McLean, VA 22102|
|DIALOG Information Services, Inc.||DIALOG; Knowledge Index|
|3460 Hillview Avenue|
|Palo Alto, CA 94304|
|Personal Bibliographic Software, Inc.||Pro-Search: DIALOG;|
|P.O. Box 4250 Pro-Search:||BRS|
|Ann Arbor, MI 48106|
|350 Longwood Avenue|
|Boston, MA 02115|
5. Haynes RB, Johnston ME, McKibbon KA, Walker CJ, Willan AR. A randomized controlled trial of a program to enhance clinical use of MEDLINE. Online J Current Clin Trials (serial online) 1993;1993 (Doc No 56).
6. Yusuf S, Collins R, Peto R, et al. Intravenous and intracoronary fibrinolytic therapy in acute myocardial infarction: overview of results on mortality, reinfarction and side effects from 33 randomized trials. Eur Heart J. 1985;6:556-85.