In Truth, The `Flood' Of Scientific Literature Is Only A Myth
By Eugene Garfield
It is obvious--clearly documentable, in fact--that the quantity of scientific literature is increasing. And it is clear that researchers must find imaginative ways--through computer searches, for example--to be more selective in their approach to taking advantage of the proliferation of printed material.
But it is inappropriate to embrace the notion that scientists are being swamped by--indeed, that they are threatened with drowning in--an ever-mounting flood of scientific journals.
I've been trying for years to lay this baseless mythology to rest, because it can foster in a conscientious researcher the debilitating feeling that he or she can't possibly keep up with what's current in a given discipline. Nevertheless, the mythology persists--despite the fact that examination of scientific journal publishing patterns and citation data should serve to debunk it.
The first project I participated in as a young information researcher at Johns Hopkins University involved a survey of medical journals. At that time, 1951, there already were thousands of biomedical serial titles. Not every serial is a journal, and some are classified as books that appear in a regular or irregular series. Countless periodicals remain "extant" as far as libraries are concerned, but most of them are, in fact, no longer published. Though deceased, they go on living--in a sense--in journal cemeteries.
The Johns Hopkins effort I was involved in (the Welch Medical Library Indexing Project) soon revealed that only a fraction of the "journal" titles were covered in any leading abstracting service. I feel comfortable in estimating that 80 percent were of minor relevance to medical research. That's not to say, of course, that there did not appear in the less frequently cited journals an occasional research gem.
In 1951, fewer than 1,000 journals were deemed important enough to be indexed comprehensively by a combination of indexing services in physics, chemistry, biology, and medicine. And fewer than 50 were ever mentioned in the press. Consequently, when I launched Current Contents in 1955, I decided to focus attention on 150 significant journals. Today, despite the flood-of-literature mythology, most of the same journals publish more than 90 percent of major scientific advances.
When my company, the Institute for Scientific Information (ISI), began publishing the Science Citation Index in 1961, we covered only 600 journals. And while SCI and other indexes now cover thousands of journals, more than 80 percent of the citations they include are to fewer than 1,000 journals.
Pride In Numbers Then what is the genesis of the myth? Well, perhaps it arises in part from the catalogs of national and scholarly libraries that traditionally have taken pride in large numbers. Their sense of doing the complete job is, I suppose, understandable. For instance, millions of books are stored in the Library of Congress; they must be preserved for posterity. And the Library of Congress, the National Library of Medicine, and the National Library of Agriculture combined need to store more than 100,000 scholarly serials of one kind or another, many of them discontinued.
It is erroneous, though, to use these vast numbers as a basis for characterizing current scientific journal production; nor is it proper to conclude from these numbers that scientific publishing is an out-of-control, ever-growing monster that cannot be contained.
Perhaps all the commotion can be traced back to 1963, when Derek de Solla Price, the Yale University science historian, dramatically called attention to the exponential growth of the scientific literature and its possible consequences if natural processes did not curtail this growth. In his book Little Science, Big Science, Price declared that "we have now a world list of some 50,000 scientific periodicals that have been founded, of which 30,000 are still being published." However, two years later, in an article in the journal Science (149:510-5, 1965), he expressed a view that would mitigate the despair. He wrote: "From a preliminary and very rough analysis of [citation] data, I am tempted to conclude that a very large fraction of the alleged 35,000 journals now current must be reckoned as merely a distant background noise, and as very far from central or strategic in any of the knitted strips from which the cloth of science is woven."
Price's disavowal was fed by ISI data and has been borne out by my own published work over the past quarter-century. Back in 1972, for example, I provided an analysis of the 152 journals most cited in the last quarter of 1969. That analysis of 1 million citations--confirming a separate, random sample covering the entire year's 4 million references--clearly demonstrated that only a small fraction of the world's journals have a significant role in the communication of primary research (Science, 178:471-9, 1972). Nevertheless, the journal myth persists. Only a few months ago, Richard Dougherty, writing in the Chronicle of Higher Education (June 19, 1991, page A32), suggested that many institutions still harbor the notion that, in terms of stored books and journals, "bigger is better."
The ebb and flow of scientific journals--owing to mergers, acquisitions, title changes, and so forth--does indeed lead to long journal lists and large collections. Many such archives are now accessible by worldwide telecommunications, but the average scientist will use them only rarely. Consider that more than half the material stored in perhaps the largest depository--the British Lending Library--has never been consulted, according to Maurice Line, its former director.
In his 1949 book Human Behavior and the Principle of Least Effort, G.K. Zipf propounded an idea relevant to the examination of the scientific literature. He made his point by addressing word frequencies in published works. When words are ranked by the number of times they are used, there is a comparatively small group that accounts for a large percentage of occurrences--the words the, a, is, be, and so forth. Likewise, when journals are ranked by the frequency of articles published or citations received, a small percentage account for the lion's share. In many human affairs, a small percent of influences accounts for a large percent of the events. And that is the nature of things: It is a "truth" that less than 1 percent of publishing American scientists are elected to the National Academy of Sciences; it is a "truth" that less than 1 percent of scientists worldwide are cited more than 1,000 times in a given 10-year period.
A significant part of the confusion about the number of current science journals is the existence of so many technology and trade journals, both paid and controlled-circulation. These publications contain much useful, applied information. Though most are rarely cited, they may or may not be essential in a university collection. But they inflate the estimate of "science journals."
Furthermore, one must consider the ambiguity in defining "journals." Every year, hundreds of print products like Annual Reviews are released. They are invaluable; they play an important integrative role in research. However, unlike primary journals, they do not usually report new advances in science. It would not be unreasonable to establish the arbitrary threshold of 100 papers a year to define a science journal in a worldwide census. Yet, in ISI's 1989 Science Citation Index, 1,500 titles--including review journals--published fewer items.
Adding to the confusion is the existence of "news" publications like The Scientist, Physics Today, C&E News, New Scientist, and even the New York Times' "Science Times" section. While each of these meritorious publications certainly accounts for at least 50 indexable articles per year, none, surely, qualifies as a primary research journal. But their existence also swells the alleged population of scientific journals because, since they are frequently consulted and occasionally cited, libraries feel legitimately compelled to store them.
Also bloating the number of "journals" are the hundreds of annual progress reports from research institutions, dutifully recorded as "serials" in various reference works. And there are the thousands of newsletters and bulletins from local medical and scientific societies.
A first-class journal, by my definition, is one that claims to publish cyclically, does just that on schedule, includes 100 or more research papers per year (more than likely, closer to several hundred), and eventually accounts for a significant number of high-impact papers. On page 11 are listings of the 50 most- cited science journals for 1969 and 1989, based on data now published by ISI in its annual Journal Citation Reports. The tables show clearly that relatively few new titles have turned up over the past two decades--that journal publication, rather than approaching flood stage, has grown in a relatively steady way. This is not to say that journal publishing has been static: Although I started Current Contents a generation ago with about 150 journals, that publication has since grown to the point at which the Life Science edition alone covers more than 1,200 journals.
But it is a myth that one must read hundreds of journals in order to stay current in one's field. Diligent researchers will selectively subscribe to as many journals as they need to read regularly; they'll consult others in libraries; they'll order reprints or photocopies if necessary.
The resourceful researcher of today does not have to throw up his or her hands in frustration; what's needed are the appropriate devices for filtering the literature.
Eugene Garfield is president and CEO of the Institute for Scientific Information and publisher and editor-in-chief of The Scientist, both headquartered in Philadelphia.
|The Scientist 5:, Sep. 02, 1991|