RT Journal Article T1 Reference Equations for Maximal Respiratory Pressures in Healthy Children and Adolescents. A1 Barral-Fernández, Margarita A1 Jácome Pumar, María Amalia A1 Souto-Camba, Sonia A1 González-Doniz, Luz A1 Ramón Belmonte, María Antonia A1 Amor-Barbosa, Marta A1 Arbillaga-Etxarri, Ane A1 Mazzucco, Guillermo A1 Bravo Cortés, Pilar A1 Del Corral, Tamara A1 Martín-Valero, Rocío A1 Llorca Cerdà, Carlos A1 Murcia Lillo, Fabiola A1 Sanchez-Santos, Jose Antonio A1 Francín-Gallego, Marina A1 Martín Cortijo, Concepción A1 García Delgado, Esther A1 Serrano Veguillas, Cristina A1 Varas de la Fuente, Ana B. A1 San José Herranz, Paula A1 González Montañez, Carolina A1 Gimeno Santos, Elena A1 Torres-Castro, Rodrigo A1 Fregonezi, Guilherme A1 Pardas Peraferrer, Mireia A1 Vilaro Casamitjana, Jordi A1 Férnzndez-Cadenas, Angeles A1 Ríos-Cortes, Antonio A1 Moreno Valera, María José A1 Langer, Daniel A1 Lista-Paz, Ana K1 Músculos respiratorios K1 Pulmones - Enfermedades en niños AB Objectives: Maximal respiratory pressures are key indicators of respiratory muscle strength; however, reference equations and cut-offs to define respiratory muscle weakness are scarce in the European paediatric population. The aim was to create sex-specific reference equations for maximal inspiratory and expiratory pressures (PImax/PEmax) in a large sample of healthy children and to objectively establish cut-offs to define respiratory muscle weakness. Methods: A multicentre cross-sectional study was conducted across 14 Spanish centres. Healthy children aged 6–18 years, stratified by sex and age, were recruited. Maximal respiratory pressures were measured following standardized methodology in accordance with international guidelines. Reference equations were developed through multiple linear regression analyses. Age- and sex specific cut-offs for respiratory muscle weakness were determined using Z-scores ≥ 1.645 standard deviation (SD) below group means. Results: The final sample included 513 subjects (257 boys; 11.5 [SD3.5] years). AB Reference equations are: (1) PImax: boys = −41.41 + 10.21 * age + 6.26 * body mass index (BMI) − 0.37 * age * BMI; girls = 125.96–0.34 * age − 0.41 * age2 − 5.75 * BMI + 0.63 * age * BMI; (2) PEmax: boys = 20.93 + 5.23 * age + 2.93 * BMI; girls = −12.67 + 11.98 * age − 0.39 * age2 + 2.57 * BMI. Cut-offs for respiratory muscle weakness are higher in boys and increase with age (p < .001). Depending on age, PImax cut-offs range from 46 to 85 cmH2O in boys and from 45 to 68 cmH2O in girls, while PEmax cut-offs span 54–98 cmH2O in boys and 57–85 cmH2O in girls. Conclusions: This study provides new reference equations for PImax and PEmax derived from the largest dataset of normative values in European children and adolescents. It also establishes age-specific cutoffs to define respiratory muscle weakness. These findings will facilitate the identification of respiratory muscle weakness and the selection of candidates for targeted training programmes. PB Elsevier YR 2025 FD 2025 LK https://hdl.handle.net/10630/41007 UL https://hdl.handle.net/10630/41007 LA eng NO Barral-Fernández, M., Jácome Pumar, M. A., Souto-Camba, S., González-Doniz, L., Ramón Belmonte, M. A., Amor-Barbosa, M., Arbillaga-Etxarri, A., Mazzucco, G., Bravo Cortés, P., Del Corral, T., Martín-Valero, R., Llorca Cerdà, C., Murcia Lillo, F., Sanchez-Santos, J. A., Francín-Gallego, M., Martín Cortijo, C., García Delgado, E., Serrano Veguillas, C., Varas de la Fuente, A. B., San José Herranz, P., … Lista-Paz, A. (2025). Reference Equations for Maximal Respiratory Pressures in Healthy Children and Adolescents. Archivos de bronconeumologia, S0300-2896(25)00336-9. Advance online publication. https://doi.org/10.1016/j.arbres.2025.09.009 NO This work was funded by a research grant from the Spanish Society of Pulmonology and Thoracic Surgery (Sociedad Española de Neumología y Cirugía Torácica, SEPAR, Spain), project 1373/2023,from The Official College of Physiotherapists from Galicia (Colexio Oficial de Fisioterapeutas de Galicia, CoFiGa, Spain) and from The“San Juan de Dios” University School of Nursing and Physical Therapy (Universidad Pontificia de Comillas, Spain). Funding for open access charge: Universidade da Coruña/CISUG DS RIUMA. Repositorio Institucional de la Universidad de Málaga RD 20 ene 2026