Age-Specific CBC Reference Intervals Support Pediatric Diagnosis in Vietnam

Complete blood count (CBC) results underpin pediatric evaluation for anemia, infection, inflammation, and platelet disorders. Yet laboratories in Vietnam have largely relied on reference intervals derived from non-Vietnamese cohorts, which can misclassify healthy children and complicate care. Population- and age-specific values are essential because hematologic parameters change markedly across childhood and may vary by ancestry and environment. New findings demonstrate comprehensive, age-specific CBC reference intervals for healthy Vietnamese children.

Researchers at Vietnam National Children’s Hospital in Hanoi established population-based, age-stratified reference intervals for CBC tests in healthy Vietnamese children. The team presented the work at ADLM 2026 in Anaheim, California, on July 28, 2026. The study addresses a long-standing gap for Vietnamese laboratories that have relied on nonlocal pediatric values when interpreting white blood cell, red blood cell, and platelet indices.

Between 2024 and 2025, investigators recruited 3,982 healthy children aged 0–19 years through community- and school-based health screening programs across multiple regions of Vietnam. Peripheral blood samples were analyzed on an automated hematology system to generate age-specific intervals. By deriving values from a large, well-distributed pediatric cohort, the approach reflects developmental physiology rather than relying on adult thresholds or non-Vietnamese pediatric norms.

The analysis confirmed that age strongly influences hematologic parameters throughout childhood. Total white blood cell (WBC) upper reference limits declined from 15.17 × 10^9/L in infants younger than 6 months to 10.71 × 10^9/L in adolescents aged 12–19 years, while neutrophil counts increased with age. Platelet counts decreased gradually across childhood, and mean platelet volume (MPV) showed modest age-related increases. Red blood cell (RBC) parameters, including RBC count, hemoglobin, and hematocrit, rose throughout childhood, with sex-related differences becoming evident after puberty. Among adolescents aged 12–19 years, hemoglobin upper reference limits were 171 g/L for males and 150 g/L for females.

According to the investigators, the primary aim is to improve laboratory interpretation and support more consistent reporting within Vietnam. Findings were presented as Abstract A-247, “Developmental changes in hematologic parameters across childhood: Establishment of population-based reference intervals in Vietnamese children,” during the Scientific Poster Session at the Anaheim Convention Center.

“Our findings are primarily intended to improve laboratory interpretation. More appropriate pediatric reference intervals may reduce the likelihood of classifying healthy children as abnormal simply because the reference values were derived from a different population. This can support more informed clinical decision-making and reduce unnecessary follow-up investigations,” said Dr. Duyen Nguyen, lead investigator, Vietnam National Children’s Hospital.

“We hope these data will serve as a national reference resource and support more consistent interpretation of CBC results in children throughout the country,” added Nguyen.