Understanding Peer Review

• the process by which scholars critically appraise each other's work to ensure a high level of scholarship in a journal and to improve the quality and readability of a manuscript. 
• applied to both primary articles (i.e. articles which present findings from original research) and review articles that summarize primary research. 

Note:    'Peer reviewed' and 'refereed' are synonyms.

How do you know if an article is from a peer-reviewed journal? Some databases allow you to limit your search to peer-reviewed journals. For other databases, you need to look up the title of the journal in Ulrich's Directory. 

1. Go to Ulrich's.

2. Type the JOURNAL TITLE (not the article title) into the search box, and click the green search button. Look for the journal title in your search results.

3. In the search results, look for a referee jersey icon to indicate that a journal is refereed. Refereed means the same as peer reviewed.

4. The Journal of Infectious Diseases is peer reviewed.  

REMEMBER:   It's the journal that's peer reviewed/refereed, so you are looking for the journal title in your search results, NOT the article title.

Many library databases include  a peer-reviewed filter which you can select to limits your search results to articles published in scholarly journals that use a peer-review editorial process  Find examples below. Questions?   Ask for assistance at your library.     

LibrarySearch

• Submit your search in UofT LibrarySearch and select "Peer-reviewed Articles" from the filter options on the left side of the screen. 

Proquest

Submit your search in Proquest and select "Peer-reviewed Articles" from the filter options on the left side of the screen.

Not necessarily.   It is also possible that some contents of a peer reviewed journal will not have been peer reviewed.

For example, editorials may not be peer reviewed but research articles generally will be. This varies from journal to journal; look for "about the journal" or "instructions to authors"  or "journal homepage" for guidance on this.   See the following examples:

• see the statement on peer review at Science ("...only some of the papers are reviewed in depth....")
• see the statement on peer review at Nature ("...the following types of contribution...are peer reviewed...other contributed articles are not usually peer reviewed...."). Note especially the 2nd and 3rd paragraphs.

When the manuscript of an article is submitted to a peer-reviewed journal, independent experts are asked to read and comment on the manuscript. If approved by the reviewers, the manuscript is accepted for publication as an article in the journal.  

Journals have different peer review standards and procedures but there are a few main types:

• Most peer review is double-blind, which means that neither the reviewers nor the authors know each other's identities.
• Single-blind is a variation where the reviewer knows who the author is, but the author does not know the reviewer.
• Open review refers to a process in which the reviewer's comments and author's replies are openly discussed before formal publication.

Every journal describes their specific peer review process in the author guidelines section of their website.  

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