New growth charts for children and adolescents in Catalonia, Spain: developed from routinely collected data (2013–2019)

BACKGROUND: Growth charts are essential for detecting early health conditions in children. This study aims to create up-to-date and region-specific growth charts for children and adolescents using large real-world data from primary care electronic health records (EHR) in Catalonia, Spain. METHODS: We used routinely collected EHR of the Institut Català de la Salut, the main primary care provider in Catalonia. We included children aged one month to 14 years with a birthweight greater than 2500 gr, and at least one anthropometric measurement registered (2013-2019). Growth references for head circumference, weight, length/height, and body mass index (BMI) were fitted using GAMLSS models. We built our charts with data recorded in 2013, validated them using data from 2014 to 2019 and compared them to WHO and Spanish growth charts. RESULTS: With a total of 876,097 records from 155,950 children, we estimated new growth charts. Our curves were higher in the highest percentile, especially for weight and BMI (starting from 4 years old), compared to the WHO standards and for extreme percentiles compared to outdated national charts but were similar to more recent national curves. Validation analyses showed similar results with differences only seen for extreme weight and BMI percentile curves, older ages and later years. CONCLUSIONS: We created new growth charts using a novel approach, accurately representing local growth patterns in the population living in Catalonia. These charts offer primary care professionals a valuable tool for assessing children's and adolescents' growth in the region.