The IDEFICS validation study on field methods for assessing physical activity and body composition in children:...

Area of Science:

• Pediatric health research
• Nutritional epidemiology
• Biometric validation studies

Background:

• Childhood obesity and lifestyle-related diseases are significant public health concerns.
• Accurate measurement of physical activity and body composition in children is crucial for effective intervention strategies.
• The IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) project aims to address these challenges.

Purpose of the Study:

• To detail the methodology, measurements, and fieldwork of the IDEFICS physical activity and body composition validation study.
• To evaluate the potential and limitations of data derived from field methods for assessing physical activity and body composition in children.
• To establish a foundation for age- and sex-specific analyses using validated methods.

Main Methods:

• A multicentre validation study involving 98 children aged 4-10 years from four European countries.
• An 8-day measurement protocol utilizing reference methods: doubly labeled water for physical activity and 3-/4-compartment models for body composition.
• Field methods included accelerometers, a physical activity questionnaire, and anthropometric measurements.

Main Results:

• Data for physical activity validation were obtained from 83-89 children, supporting age- and sex-specific results.
• Body composition validation data were available for 64-80 children, allowing sex-specific analyses but limited power for children under 6.
• Activity energy expenditure estimates varied by center, sex, and age, with boys and older children showing higher values; normalization by body weight reduced most differences, except country-specific variations.

Conclusions:

• The IDEFICS validation study provides a robust dataset for age- and sex-specific investigations into the validity of physical activity and body composition field methods.
• Compliance with field methods was higher than with reference methods, indicating their feasibility for large-scale studies.
• Findings support the use of these validated field methods in diverse European populations for future research on children's health.