García, GuadalupePérez-Ríos, MónicaRuano Raviña, AlbertoCandal Pedreira, Cristina2024-04-242024-04-242024Journal of Clinical Epidemiology, Volume 169, 2024, 1113130895-4356http://hdl.handle.net/10347/33650Objectives: This study aims to assess the quality, risk of bias, and conflicts of interest (COIs) of clinical trials conducted on the effects of fortified infant formula. Study Design and Settting: Systematic review including all randomized clinical trials targeting healthy children and using three arms: fortified infant formula; standard formula; and breastfeeding. We performed a descriptive analysis of the studies reviewed, assessed their quality using the “Risk of Bias 2- RoB 2” tool, and identified COIs. Results: A total of 40 studies were included. All showed a high overall risk of bias, with this being especially noteworthy in the “deviations from intention to treat” and “missing outcome data” domains. Of the total included studies, 29 reported conclusions in favor of the fortified formula; 15 studies reported multiple conclusions that were either contradictory or not in line with the results. COIs with industry were identified in 33 studies, and in 17 studies, these conflicts were not declared in the appropriate section. Conclusion: From a methodological perspective, studies on fortified infant formula display low quality, made evident by the high risk of bias. Additionally, there are frequent COIs. These aspects must be considered by health professionals and the population when drawing up recommendations for the use of this productengAtribución-NoComercial 4.0 Internacional@2024 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC license (http://creativecommons.org/ licenses/by-nc/4.0/)http://creativecommons.org/licenses/by-nc/4.0/Conflict of interestInfant formulaIndustryQualityBreast feedingFundingjournal article10.1016/j.jclinepi.2024.111313open access