Letters to the Editor are an essential aspect of postpublication review. The International Committee of Medical Journal Editors has recommended that all biomedical journals provide “a mechanism for submitting comments, questions, or criticisms about published articles, as well as brief reports and commentary unrelated to previously published articles. This will likely, but not necessarily, take the form of a correspondence section or column. The authors of articles discussed in correspondence should be given an opportunity to respond, preferably in the same issue in which the original correspondence appears.”8 Published letters usually comment on an article previously published in the same journal, and replies from the authors of the article can make for lively and useful exchanges. Indeed, providing published responses to questions and criticisms is part of the responsibility of authorship.
Most journals request that such letters to the editor be sent within a specified period (often about a month) after publication of the original article. Journals rely on these reader responses as part of postpublication peer review and quality assurance. Letters should focus on the scientific, clinical, or ethical issues raised by the original article and should not include ad hominem attacks on the authors. Often 1 or 2 letters are chosen for publication as being representative of the responses to a particular article.
Letters not pertaining to a previous article may report original research data, describe a problem, or report a case. Letters reporting original research should follow the same IMRAD format as a full-length research article but in a substantially truncated length. Journals usually have strict limitations for the length and the number of references for published letters. Letters submitted for publication may be subject to review and revision, and they require statements of authorship responsibility, disclosure of conflicts of interest, and copyright transfer. Correspondents should indicate whether letters sent to the editor are to be considered for publication.