Cell Tops In Impact, High In Immediacy

“If you were stranded on a desert island,” as the proverbial question goes, “which 10 books would you want to have with you?” The Scientist recently asked itself this question, but with a twist: “Which 10 journals publishing orig nal research reports would a cast-away life scientist wish to have regularly air-dropped to his or her island?” Certainly, the answer depends on the individual scientist, but one method of pursuing a general answer might be to ide

Jul 24, 1989
David Pendlebury

“If you were stranded on a desert island,” as the proverbial question goes, “which 10 books would you want to have with you?”

The Scientist recently asked itself this question, but with a twist: “Which 10 journals publishing orig nal research reports would a cast-away life scientist wish to have regularly air-dropped to his or her island?”

Certainly, the answer depends on the individual scientist, but one method of pursuing a general answer might be to identify those journals that exhibit the highest impact, a measure of how frequently the “average article” in a given journal is cited.

The accompanying table lists the 10 highest-impact journals in 1988. (Review journals, such as those in the Annual Review series, were excluded in this survey. For a variety of reasons, review journals, which contain articles summarizing the work of many investigators, tend to be cited more frequently than journals publishing original research, so four of five of the highest-impact journals are typically review journals. These publications will be the subject of a separate, future survey.)

The Top 10

For 1988, The Scientist’s investigation revealed that Cell topped the list—a fact that might be expected, since that journal has been the highest-impact nonreview publication in eight of the last 10 years, bested by the New England Journal of Medicine only in 1983 and 1985. NEJM ranked second in 1988, as it did eight times since 1979. In fact, these two journals stand head and shoulders above all others once again as the highest-impact life sciences journals—Cell being the premier journal of molecular and cellular biology, and NEJM serving as the favored journal of clinical medicine (see “Among Leading Medical Journals, It’s NEJM That Sets The Citation Pace,” The Scientist, November 28, 1988, page 15).

Science placed third for 1988, and that is notable. In 1979, both Nature and Science had an equal impact (5.9). Throughout the next de cade, each markedly increased its impact (see “Nature’s Fortunes, And Those Of Science And PNAS, Too,” The Scientist, July 11, 1988, page 17). But while both moved ahead, it was always Nature that outpaced Science. Now, for the first time in 10 years, Science has exceeded Nature, if only by a small margin. Nature’s impact rating has remained essentially flat since 1986.

The impact rating used here is a measure of the extent to which a journal’s articles are cited, on average, in the scientific literature. The Institute for Scientific Information (ISI) in Philadelphia calculates the impact of several thousand journals annually, publishing these data in its Journal Citation Reports, based on the Science Citation Index. To determine a particular journal’s impact, ISI counts citations from all the journals it indexes during a given year to the articles published in that journal over the previous two years and divides that figure by the total number of articles ‘published in that journal in those two years.

For example, the 863 articles published in Cell in 1986 and 1987 were cited 20,637 times in the 1988 Science Citation Index, which gives Cell an impact factor of 23.9 for 1988. All journals in the top 10 published more than 530 articles in the years 1986 and 1987, which attracted at least 4,500 citations in 1988. The journal that published the most articles in 1986 and 1987 was Proceedings of the National Academy of Sciences, USA (PNAS) [3,968] this publication also received the greatest number of citations to its 1986 and 1987 articles in 1988 (39,805).

The Lancet ranked fifth for 1988. iT has shown a sharp increase since 1984, when it recorded an impact rating of 9.4. Another steady improvement has been recorded by EMBO Journal, which first entered the top 10 FOR nonreview journals in 1986. In 1983 its impact was just 5.1. Annals of Internal Medicine first entered the top lOin 1983; it has since held either ninth or 10th position.

Some Fall In Rank

A few AMONG the top 10 have not increased their impact in the past decade, and, since others have been moving ahead these are dropping in rank. PNAS in one example of this phenomenon. It ranked fourth in impact among nonreview journals in 1979, fifth in 1980, sixth in 1981, back to fifth in 1982, then to sixth in 1983 and 1984, and to eighth in 1985, where it has remained since.

The Journal of Experimental Medicine is another example. It placed third from 1979 to 1982, fourth in 1983, moved back to third in 1984, to fith in 1985, and has been in 2nd place since 1986:
The Journal of Cell Biology has also been declining in rank over the past decade. It ranked as high as fourth in 1980 and 1982, but now stands in ninth place.

Also listed in the table on page 14 are the 1988 immediacy figures for these 10 high-impact journals. Immediacy measures how quickly the “average article” in a particular journal is cited. For example, the 1988 immediacy index of Cell was calculated by dividing the 1,846 citations recorded from all journals to Cell’s 1988 articles by the number of articles published by Cell in 1988, which was 423. This gives Cell an immediacy index of 4.4, which is among the highest in the group. NEJM and The Lancet exhibited the highest 1988 immediacy rating of the top 10—4.6.

The record of Cell speaks for itself. Both the impact and the immediacy ratings of the publication combine to make it molecular biology’s leading journal.

So, if one day at the beach you should happen to find a message in a bottle that has washed up on shore, don’t be surprised if that message reads: "Just send Cell.”

David Pendlebury is an analyst in the corporate research department at The Institute for Scientific Information, Philadelphia.