Neonatal Eating Assessment Tool - Mixed Breastfeeding and Bottle-Feeding (NeoEAT - Mixed Feeding): factor analysis and psychometric properties.

Background: Early identification of feeding difficulty in infancy is critical to supporting breastfeeding and ensuring optimal nutrition for brain development. The Neonatal Eating Assessment Tool (NeoEAT) is a parent-report assessment that currently has two versions: NeoEAT - Breastfeeding and NeoEAT - Bottle-feeding for use in breast and bottle-fed infants, respectively. There are currently no valid and reliable parent-report measures to assess feeding through a combination of both breast and bottle delivery. The purpose of this study was to conduct a factor analysis and test the psychometric properties of a new measure, the NeoEAT - Mixed Breastfeeding and Bottle-Feeding (NeoEAT - Mixed Feeding), including internal consistency reliability, test-retest reliability, construct validity and known-groups validity.

Methods: Parents of infants younger than 7 months who had fed by both bottle and breast in the previous 7 days were invited to participate. Internal consistency reliability was tested using Cronbach's α. Test-retest reliability was tested between scores on the NeoEAT - Mixed Feeding completed 2 weeks apart. Construct validity was tested using correlations between the NeoEAT - Mixed-Feeding, the Infant Gastroesophageal Reflux Questionnaire - Revised (I-GERQ-R), and the Infant Gastrointestinal Symptoms Questionnaire (IGSQ). Known-groups validation was tested between healthy infants and infants with feeding problems.

Results: A total of 608 parents participated. Exploratory factor analysis revealed a 68-item scale with 5 sub-scales. Internal consistency reliability (Cronbach's α = .88) and test-retest reliability (r = 0.91; p < .001) were both acceptable. Construct validity was demonstrated through correlations with the I-GERQ-R (r = 0.57; p < .001) and IGSQ (r = 0.5; p < .001). Infants with feeding problems scored significantly higher on the NeoEAT - Mixed Feeding, indicating more problematic feeding symptoms, than infants without feeding problems (p < .001), supporting known-groups validity.

Conclusions: The NeoEAT - Mixed Feeding is a 68-item parent-reported measure of breast- and bottle-feeding behavior for infants less than 7 months old that now has evidence of validity and reliability for use in clinical practice and research. The NeoEAT - Mixed Feeding can be used to identify infants with problematic feeding, guide referral decisions, and evaluate response to interventions.