Peer Review? What? And Why?
Sagar V. Krupa
Since attending ICPEP-2 (International Conference on
Plants and Environmental Pollution) in Lucknow, India in 2002, I have been
asked on several occasions about the “Peer Review” process associated with the
Conference papers, prior to their acceptance and publication. Some from the
developing countries felt that their reputation and stature were being
challenged, while others believed that it was an unnecessary irritation.
I have served for some 20 years as an Associate
Editor of the journal “Environmental Pollution” and I am also the Chief Editor
for the Book Series “Developments in Environmental Science.” Elsevier Science
of Amsterdam, Netherlands, publishes both. I also act as a peer reviewer for
manuscripts from some 10 different international journals. Thus, when Dr. K. J.
Ahmad (Secretary, ISEB) invited me to write this article regarding the
aforementioned subject, I readily agreed.
A “peer” is defined as “a person of equal standing.”
Scientific recognition, reputation and respect among others are intimately
associated with peer opinion. Peer reviews are used in, 1. Selecting an
employee, determining promotions, 2. Awarding funding (grant) for a particular
cause, 3. Assessing the quality of teaching in a classroom and 5. Determining
the merits of a particular work for publication. There are other examples as
Peer review can be conducted in several different
ways. They include: 1. Seeking the opinions of individuals in a population, as
in human epidemiological research, 2. Using a panel of experts to select which
research proposal should be funded or writing an authoritative document that
has wide implications, 3. Using student opinions, coupled with those of the
peer colleagues in determining the quality of teaching by an individual in a
classroom and 4. Using two or more experts in assessing the quality of a
manuscript for its publication in a journal. No doubt, there are still other
ways of conducting peer reviews, as in human medicine and in Biotechnology.
Peer review is a mechanism for preserving the
originality, authenticity, validity and quality of a particular work. It is
also a way to prevent “plagiarism”. Certainly some of those issues have led to
controversy. Nevertheless, peer review is the standard and widely accepted
method for evaluating the quality of papers submitted for publication, even in
Peer reviews have their own problems. In some cases
there can be a conflict of interest or a pre-determined scientific view on the
part of a reviewer that may influence his or her review. Many peer review
processes require the reviewer to disclose such information a priori, so that
such individuals are not included in the overall process. Failure to disclose
such information can frequently lead to disservice and penalties. Another
source of the problem can be, when the Editor of a journal who serves as an
adjudicator errs in selecting the reviewers.
Although many peer reviewers are dedicated and take
their task very seriously, others do not. At least in some US Universities,
there are no institutional rewards for the time spent in peer reviews. That
makes it difficult for young faculty members seeking promotion. I was quite
impressed by a young scientist who expressed his profound apologies to me for
his inability to perform a review, because he was too involved at that time in
collecting field data for a publication (one of the requirements for his
promotion), but given another opportunity, would enjoy the effort and would
welcome it. What an honest response? Another young faculty member produced a
5-page review on a 10- page manuscript. The most impressive aspect of that
review was, every one of the comments was directed at making the paper better.
How can the authors of the paper get any more unsolicited help?
In contrast, some potential reviewers never respond
to a request a priori for assistance, in spite of repeated queries. However,
once agreed, the reviewer should provide his or her comments expediently. There
are reviewers who neither provide their comments nor return the copy of the
manuscript after agreeing to do the review. That is a total disservice to the
authors and to the scientific community. As such things happen, names of the
individuals involved are removed from future consideration for requesting help.
As one of my colleagues put it, peer review preserves the quality of science
and you owe it to your colleagues to be helpful to them. Otherwise, you are
doing a disservice to your profession. There have been suggestions by members
of some scientific societies to penalize delinquent peer reviewers by delaying
their publications and rewarding others, who are diligent and prompt in their
obligations, by expediting their papers after acceptance. As a person
(speaking for myself) who faces those issues every day, what a refreshing
thought for future consideration?
All international journals require manuscripts to be
reviewed by two anonymous peers. For example, Editors maintain a directory of
scientists and their areas of specialization for use in the process. If the
comments from the initial two peer reviewers are contradictory in their nature
(happens about 20% of the time), then a third peer reviewer is requested to
help, but without providing the benefit of the comments from the first two. It
is important to realize that the identities of the peer reviewers are not
disclosed to the authors and is a part of the confidentiality of the process to
promote scientific integrity.
If the initial two reviewers recommend the paper for
publication, but have questions and suggest revisions, then the authors should
respond to those by providing an itemized listing of their responses to the
Editor in submitting their final or revised version. The Editor always examines
the author’s responses to see whether they are satisfactory before accepting a
Some authors do not readily accept peer review
comments. Once I was forced into a debate with an author, who essentially
informed me that I did not know the subject matter of his paper. The author
used data on carbon monoxide concentrations at traffic intersections to discuss
carbon dioxide emissions in global climate change.
Peer reviewers are requested to provide
constructive, unbiased, but candid comments regarding: (1) Appropriateness of
the manuscript content to the mission of the journal, (2) Relevance of the
study, (3) Rigor and soundness of the science, (4) Importance of the results in
advancing the science, (5) Appropriateness of the methods used and the
conclusions reached in addressing the objectives. There are still other
Many authors seek to publish their papers in the
most appropriate and leading journals in their field. Different journals
implement peer reviews with different degrees of rigor. Top international
journals have manuscript rejection rates of 40-60% of the total number
submitted by the authors. That is reflected in the quality of papers published
and the established reputation of the journal. An experienced scientist can
assess the quality of a publication even without reading it, by simply looking
to see where it is published. A manuscript rejected by one journal may appear
in another journal that has less rigorous standards or because a different set
of peer reviewers were used, who perhaps examined the paper less rigorously.
For example, strictly based on scientific reasons, I once rejected a paper
twice. At first it was sent to me by one journal and after my rejection,
coincidentally it was sent to me again some months later by another journal.
After the second rejection, the paper subsequently appeared in a journal that I
seldom consult. Thus, without doubt there is a hierarchical order of quality
It is not uncommon that a paper written by a reputed
scientist can be subjected to serious questions from peer reviewers. In such
cases, to sustain their reputation, although it might take extra time and
effort, the authors generally resubmit their paper for consideration,
responding to all of the peer comments,
Some journals also allow resubmission of a paper for
the second time after major or significant revisions, for a re-evaluation by
the original peer reviewers. Such a process must be approved a priori by the
journal Editor. However, that practice is not very common (perhaps 5%) and some
journals, do not allow a re-submission.
Publishers themselves use what is known as the
“impact factor” to assess the quality of their journals. For example, according
to the Institute for Scientific Information (ISI), the impact factor of a
journal is calculated by dividing the number of current year citations to the
source items published in that journal during the previous two years. In that
context, for example, Elsevier Science publishes each year, a listing of the
most down loaded articles in their journals.
In summary, peer review is usually a constructive
process that assures the quality of a work. To be challenged by your peers can
only improve the contents of your work and its merit. In a sense, every true
democracy in the world has a peer review of its political and socio-economic
status by its eligible populous. At the appropriate time, an elected leader is
evaluated for his or her performance to be reelected to office or to be
Prof. Sagar V. Krupa is the Professor of Plant Pathology at the, University of
Minnesota Twin City Campus, St. Paul, Minnesota, U.S.A.