Letter Regarding: Clarifying the Study Design Nomenclature: Quasi-Experimental Versus Case-Control in ‘Feasibility of Low-Volume Atomized Povidone-Iodine as a Peritoneal Antiseptic in Complicated Appendicitis’


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Akay M. A., Metin S., Özden M. E.

JOURNAL OF SURGICAL RESEARCH, cilt.2026, ss.1-2, 2026 (Scopus) identifier

Özet

We read with great interest the article by Bates et al.1 entitled "Feasibility of Low-Volume Atomized Povidone-Iodine as a Peritoneal Antiseptic in Complicated Appendicitis," published in the Journal of Surgical Research. The authors investigated the feasibility of a novel antiseptic technique, low-volume atomized povidone-iodine (LVAP), compared to standard practice for reducing postoperative abscess rates. While we commend the authors for their innovative approach to intraoperative antisepsis, we wish to address a methodological terminology issue. The authors describe their study design as a "retrospective case-control study." We believe this label incorrectly categorizes the research design and risks misrepresenting the causal framework, which is a common mistake in the literature.2,3 In a traditional case-control study, participants are selected based on the presence (cases) or absence (controls) of the outcome of interest, and the investigators look back to assess exposure. Crucially, in such designs, the odds ratio is calculated to demonstrate the strength of the association between the exposure and the outcome.4,5 By contrast, Bates et al. grouped patients based on the intervention received (LVAP versus standard practice) and then assessed the subsequent outcomes. Given that the study involves a nonrandomized intervention where an active treatment (LVAP) was introduced by a specific surgeon and compared to a control group selected via propensity matching, the design is best classified as quasiexperimental. Unlike observational case-control studies, this study evaluates the effect of a specific clinical manipulation without random assignment. Accurate classification of study designs―distinguishing between case-control, cohort, and quasi-experimental studies―is essential for the scientific record. It ensures proper interpretation ofthe results and correct classification in future systematic reviews and meta-analyses. We respectfully suggest that describing this valuable work as a quasi-experimental study would more accurately reflect its methodological rigor.We appreciate the authors’ contribution to the management of pediatric appendicitis. Disclosure None declared.