A global perspective on the accuracy of pediatric weight estimation methods in emergency care: A systematic review

INTRODUCTION: In pediatric emergency services, it is essential to know the patient's weight, for which there are numerous estimation tools. However, these instruments present biases in calculating the patient's weight. Therefore, the objective of this study was to evaluate the validity of pediatric weight estimation methods available worldwide, comparing their accuracy and applicability in medical practice. METHODS: A systematic review was conducted following the PRISMA recommendations (PROSPERO Registration Number CRD420251174686). Observational and validation studies with original data published from 2010 to July 2025 were included. Articles were searched for in ProQuest, Web of Science, PubMed/Medline, and Scopus. The inclusion criteria were: patients aged 0 to 18 years, weight estimation methods, and quantitative reports of accuracy. RESULTS: Thirty-one studies from all continents were selected. Two-dimensional methods were generally more accurate than those based solely on age or one-dimensional formulas, especially in populations with a high prevalence of overweight or obesity. Parental estimation also performed well. Heterogeneity was observed in age ranges, acceptable error and validation criteria between studies. CONCLUSIONS: Within the limitations of the uneven global evidence base, the tools that appear most reliable for estimating pediatric weight in emergency departments are those that incorporate more than one anthropometric variable or are supported by local validation. Given the scarcity of data from various regions and specific populations, each emergency system must determine the approach that best suits its local demographic profile, invest in staff training, and apply standardized validation criteria before adopting changes in routine practice.