Developing Growth Reference Curves for Jordanian Children and Adolescents: A Comparative Analysis with WHO Growth...

Background: Growth standards and growth references serve different purposes. The WHO Child Growth Standards for ages 0-5 years describe growth under specified optimal conditions, whereas the WHO 5-19-year curves are a reference reconstructed from historical NCHS data. This study aimed to develop sex-specific growth reference curves for Jordanian children and adolescents and compare selected centiles descriptively with WHO growth standards and references. Methods: Retrospective anthropometric records collected between 2019 and 2025 through the Ministry of Health's Hakeem National E-Health Program were used. Following medical eligibility screening, 63,187 measurement records were selected before analytical cleaning using proportionate stratified random sampling by sex and governorate, with age balancing across four broad age groups. Analytical cleaning excluded 506 boys' and 1084 girls' records, producing a final height-for-age and BMI-for-age sample of 61,597 measurement occasions from 33,170 Jordanian children and adolescents (27,933 occasions from 14,594 boys and 33,664 occasions from 18,576 girls). Weight-for-age used 16,071 occasions from 9537 boys and 16,185 occasions from 10,214 girls aged 2-10 years. LMS/BCPE-based centile modeling was conducted within GAMLSS, and the 3rd, 15th, 50th, 85th, and 97th centiles were compared with WHO values. Results: Separate sex-specific models were developed, and the Jordanian curves differed descriptively from WHO curves at several ages and centiles. Conclusions: The population-proportionately stratified Jordanian curves provide direct local context for describing attained anthropometric distributions. Future studies should compare both the Jordanian and WHO curves against Jordan-specific outcomes and classification decisions to determine their respective clinical roles.