Embracing Letters to the Editor: Classifying Types of Letters into Disagreement, Agreement, and Complementary.

"Letters to the Editor" that address original articles significantly contribute to medical literature. Utilizing letters published in obstetrics and gynecology journals as a study model, I aimed to classify letters according to their context, providing a valuable framework for readers to comprehend the significance of letters and for authors to effectively write them. Using a sample of 40 recent letters from the Journal of Obstetrics and Gynaecology Research (JOGR), I classified letters into three main categories based on their attitude to addressed articles: Disagreement, Agreement, and Complementary. I further subclassified each category into subcategories, including "Interpretation claim," "Data addition," and "Historical viewpoint." The same procedure was carried out for the 24 most recent letters from BJOG and the American Journal of Obstetrics and Gynecology and also for the JMA Journal. Disagreement letters were prevalent in all three OBGYN journals, accounting for 1/2 to 2/3 of all letters. The rest letters were categorized either as "Agreement" or "Complimentary." Subcategorizations demonstrated different ratios of letters of the three categories among journals. I believe that the attempt to categorize and subcategorize letters offers valuable insights into the letters, potentially enhancing clarity in medical literature communication.