Our readers' voice. Letters to the editor are an important component of the discussion of scientific articles, in Deutsches Arzteblatt as in other journals. our correspondence pages reflect a diversity of opinion thanks to the love of debate among our readers--and thanks to a few rules

Letters to the editor on the Zika virus: a bibliometric analysis

Objective:

To conduct a bibliometric analysis of Letters to the Editor published on the Zika virus from 1952–2018.

Methods:

A PubMed search was conducted using the terms (Zika OR ZIKV). Results were limited to 1952–2018 and Publication Type = Letter. Results were exported to EndNote, and the full text of each Letter examined. Each Letter was assigned to one of five categories: Reader Response, Author Reply, Observation, Case Report, or Research. Additional study parameters included number of authors, number of references, use of graphics, and funding. Citation reports were generated for each category and the entire dataset, producing lists sorted by Times Cited.

Results:

Of 499 Letters, only 15 (3.0%) were published before 2016. In 2016, at the height of the Zika virus epidemic in the Americas, 244 (48.9%) Letters were published, dropping to 145 (29.1%) in 2017 and 95 (19.0%) in 2018. Letters included 149 (29.9%) Reader Responses, 56 (11.2%) Author Replies, 112 (22.4%) Observations, 70 (14.0%) Case Reports, and 112 (22.4%) Research. The Letters were written by 1–35 authors; 369 (74.0%) Letters had 1–5 authors, and 130 (26.0%) had 6 or more. The Letters cited 0–63 references, with an average of 7.0 per Letter. Graphics appeared in 192 (38.5%) Letters, and 77 (15.4%) Letters reported funding. An interesting anomaly was the 104 (20.8%) Letters authored or co-authored by 1 individual.

Conclusion:

Letters to the Editor remain an important component of scientific communication and may serve as a valuable source of clinical and research information.

What do letters to the editor publish about randomized controlled trials? A cross-sectional study

Background

To identify published letters to the editor (LTE) written in response to randomized controlled trials (RCTs), determine the topics addressed in the letters, and to examine if these topics were affected by the characteristics and results of the RCTs.

Methods

Comparative cross-sectional study of a representative sample of RCTs from a set of high-impact medical journals (BMJ, Lancet, NEJM, JAMA, and Annals of Internal Medicine). RCTs and their published LTE were searched from these 5 journals in 2007. Data were collected on RCTs and their characteristics (author affiliation, funding source, intervention, and effect on the primary outcome) and the topics addressed in published LTE related to these RCTs. Analysis included chi-square and regression analysis (RCT characteristics) and thematic analysis (LTE topics).

Results

Of 334 identified RCTs, 175 trials had at least one LTE. Of these, 381 published LTE were identified. Most RCTs, tested drug interventions (68%), were funded by government (54%) or industry (33%), and described an intervention that had a positive impact on the primary outcome (62%). RCT authors were primarily affiliated with an academic centre (78%). Ninety percent of the 623 LTE topics concerned methodological issues regarding the analysis, intervention, and population in the RCT. There was a significant association between funding source and impact on outcomes (p = 0.002) or type of intervention tested (p = 0.001) in these trials. Clinical and “Other” LTE topics were more likely to be published in response to a government funded RCT (p = 0.005 and p = 0.033, respectively); no other comparisons were significant.

Conclusions

This study showed that most LTE are about methodological topics, but found little evidence to support that these topics are affected by the characteristics or results of the RCTs. The lack of association may be explained by editorial censorship as a small proportion of LTE that are submitted are actually published.