A REVIEW ARTICLE can stale quickly if the field it covers is developing rapidly. To counteract that problem, Chemical Reviews , a monthly journal published by the American Chemical Society, is experimenting with a strategy to extend the shelf life of some of its review articles. Authors who are so inclined can update the online version of their articles, creating what the journal calls a "perennial review." To highlight the changes, the journal marks up new text and references within the updated article in red and frames new art in a blue box. The journal published its first perennial review in November 2006.
The gestation period for this step was a long one: The concept was initially championed some five years ago by Associate Editor Robert D. Kuchta. Editor-in-Chief Josef Michl and Associate Editor John A. Gladysz eagerly embraced the idea. The trio then surveyed authors and approached the journal's advisory board for feedback.
"Although the consensus was that this would be a good idea to try, it definitely was not unanimous," says Michl, a physical organic chemist at the University of Colorado, Boulder. For example, one critic thought "this might lead to a situation where a particular author would appropriate an area of science and keep it exclusively to himself to review, and this might stifle controversy and discussion. This was part of the reason we decided there should be a five-year limit on the time during which an article can be updated."
Others worried that authors might feel they had an obligation to update their reviews and so would be reluctant to submit manuscripts to Chemical Reviews, Michl says, "so we try to make it very clear that this is entirely voluntary."
Gladysz, an organic chemist at the University of Erlangen-Nuremberg, in Germany, wrote the first perennial review with Slawomir Szafert, an organometallic chemist at Poland's University of Wroclaw. Posted online in November 2006 (DOI: 10.1021/cr068016g), the article includes about 35% more data than the authors' original 2003 review on the structure of conjugated polyynes (DOI: 10.1021/cr030041o). "In many cases, what were tentative proposals earlier could be recast as definitive conclusions" in the update, Gladysz notes. "In one or two cases, earlier proposals were not supported by the newer data."
When Gladysz and Szafert wrote the initial article, the journal was already developing the concept of a perennial review. So the two authors intentionally gave the original article a "structure that would lend itself to a later update," Gladysz says. "We gave some thought to numbering systems for compounds and graphics that might allow additional compounds and graphics to be more easily inserted later." After writing the update, the authors realized that a different type of article might require a somewhat different updating style, Gladysz says. "It will be exciting to see how all of this evolves with participating authors, and whether a small group of dominant styles might emerge that could be used to guide authors new to the process."
The journal editors intentionally relied on one of their own as a guinea pig for the experiment. "We felt that we should subject ourselves to the drama first," Michl explains with a chuckle. "We thought it would be a good idea to go through the process ourselves, to then be able to answer questions from other would-be authors. There were many details that needed to be sorted out, and they would be most readily sorted out by ourselves." Examples included the method for inserting new references—" 'Do you mark them separately or do you renumber all the references that you had in the paper?' We debated all of this at length," he says.
Overall, though, the details the editors had to settle were fairly straightforward, recalls Kuchta, an enzymologist at Colorado. "The harder issues were faced by the technical people at ACS," he adds. "It's nontrivial to be able to change an article" into a perennial review.
CHALLENGES SURFACED because the production system for ACS journals includes automated steps that ensure that the content in the print edition matches the Web edition, says Ann M. McCarty, an ACS technical editor whose team of information technology and production staff helped overcome many of the production-related hurdles that arose during the launch of the perennial reviews.
One challenge cropped up because perennial reviews are listed in the table of contents of both the print and online editions of the journal, but the updated articles themselves appear only in the Web edition. "It would be far too expensive and demanding to try to publish them in the print version," Michl explains.
That's a sensible publishing decision—but it's unprecedented in ACS journal production, and the automated production system required manual intervention to cope with the different print and Web versions, McCarty says. ACS is working to make the production system more adaptable.
The editors of Chemical Reviews have fielded quite a few inquiries about their experiment from prospective authors. Michl expects to publish the next perennial review—written by an author who isn't affiliated with the journal—in May. Several other authors have expressed interest, a promising sign given that the trial was announced so recently.
Readers have also contacted the editors with questions. "This is an entirely new experiment in chemical publishing, so some of these answers still have to be worked out," Michl says.
Some correspondents wanted to know how to cite a perennial review—whether to use the reference of the original article or the new version. ACS recommends that the new version be cited with its own reference, using page numbers such as PR1-PR33.
Other readers were curious whether updates would be scrutinized as thoroughly as initial manuscripts. Prior to acceptance, Chemical Reviews subjects each of its original articles to intense peer review by as many as a half-dozen referees. "The job is huge," says Michl, who is grateful that reviewers are willing to put in the effort needed to digest the material. "Typically, the manuscripts are 100, 200, even 300 pages, and reading and reviewing an article like that often results in a referee report that has many pages." Updates, he says, will generally not be reviewed as thoroughly. "Some of the time, it will be possible for the editors to do the review without sending it to the original reviewers."
The frequency with which a particular review is updated will be left to the discretion of the authors, "who should make a decision based on the flow of new results," Szafert says.
"We would not object if they wanted to do it every year," Michl says. But a perennial review can't be extended beyond five years after the original publication date. "After that, we feel that it would be too much of a patchwork, and it would be better to start from scratch and write a whole new review article," Michl says.
Apart from the original senior author, the list of authors for an updated review doesn't have to match the original list. That policy recognizes that coauthors may have moved on to other institutions or taken on other responsibilities that leave little time to undertake such a project, Michl says.
Although Chemical Reviews is flexible about authorship, it has no intention of opening perennial reviews up to Wikipedia-type collaborative public revision. "It would be difficult to have contributions from anywhere in the world and still keep the senior author responsible for the content," Michl explains.
He believes Chemical Reviews is the first chemistry journal to introduce updated online reviews. Other chemistry journals likely will be interested in seeing how the trial pans out.
Angewandte Chemie , which publishes reviews as well as highlights and communications, isn't currently planning anything analogous to the perennial reviews, according to Editor Peter Gölitz. But "we certainly watch what others are doing and look forward to seeing the experience that Chemical Reviews has with this experiment," he says.
The Royal Society of Chemistry's Chemical Society Reviews doesn't offer an equivalent of perennial reviews per se. But in a field that's developing rapidly, the journal will often commission an update a few years after publishing a successful initial review, says Editor Robert D. Eagling. Success is gauged by factors such as the number of citations and the number of online viewings of the original review. For instance, the journal recently published an update (DOI: 10.1039/b610714a) of a 2002 review (DOI: 10.1039/b201099m) about the creation of chiral systems from achiral and racemic compounds. The updated review appears in both the print and online versions of the journal.
In fields outside of chemistry, at least one organization publishes review articles based on a philosophy similar to that of perennial reviews. Germany's Max Planck Society publishes Living Reviews in Relativity and Living Reviews in Solar Physics, which are free, peer-reviewed, online-only journals.
THESE JOURNALS' international editorial boards solicit reviews from experts, who are expected to regularly update the articles with the latest developments in their fields. The relativity journal, for instance, encourages authors to submit annual updates, with a major revision every two or three years.
The Max Planck Society says the concept originated with Bernard F. Schutz and Jennifer Wheary, who launched Living Reviews in Relativity in 1998. Living Reviews in Solar Physics debuted in 2004. Though the two journals have been around for a while, neither contains much material: The relativity journal published six articles last year and the solar physics journal published two.
Journals aren't the only venue for updated articles. For instance, Wiley updates the online version of Ullmann's Encyclopedia of Industrial Chemistry on a quarterly basis and revises the CD-ROM version annually.
As authors and reviewers for these other publications may have found, "It is a lot less work to update an article than to write a new article from scratch," Michl says. "If the updated article serves the function, then that saves everybody's time—it's a good thing to do."
Michl wants to give the perennial review experiment five years before deciding whether it's a success. "The best indicator will be how many authors submit perennial reviews," he says. An informal poll of Chemical Reviews authors "indicated that perhaps one out of 10 or 20 articles will be renewed as perennial reviews. If we come up to that kind of percentage, then I would say it certainly serves a useful function. All three of us are hoping that this will turn out to be a successful venture and will start a new chapter in chemical publishing," Michl says. "Maybe we'll fall on our face. But the hope is that this will be recognized in the future as an important step in chemical publishing."