Related Experiment Video
Updated: Apr 18, 2026
Quantified Assessment of Infant's Gross Motor Abilities Using a Multisensor Wearable
Published on: May 17, 2024
Do currently recommended Bayley-III cutoffs overestimate motor impairment in infants born <27 weeks gestation?
A F Duncan1, C Bann2, C Boatman3
1Department of Pediatrics, Division of Neonatology, University of Texas Health Science Center at Houston, Houston, TX, USA.
Insights
A Bayley-III motor composite score of 85 may overestimate moderate-severe motor impairment in preterm infants. A lower cut-point of 73 improves accuracy in identifying motor deficits, distinguishing mild from severe impairment.
Area of Science:
- Neonatal research
- Developmental pediatrics
- Motor function assessment
Background:
- The Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) is widely used to assess motor skills in infants.
- A motor composite score of 85 is often considered a threshold for moderate-to-severe motor impairment.
Purpose of the Study:
- To evaluate if the Bayley-III motor composite score of 85 accurately identifies moderate-to-severe motor impairment.
- To analyze individual Bayley-III motor components and establish more precise cut-point scores.
Main Methods:
- Retrospective analysis of 1183 children born preterm (<27 weeks gestation).
- Evaluations conducted at 18-22 months corrected age.
- Gross Motor Function Classification System (GMFCS) used to determine gross motor impairment; statistical analyses included regression and sensitivity/specificity.
Main Results:
- Bayley-III motor composite scores effectively indicated gross and fine motor impairment.
- A motor composite cut-point of 73 significantly enhanced specificity (94%) for identifying impairment compared to a cut-point of 85 (76%).
- A Fine Motor Scaled Score below 3 differentiated mild from moderate-to-severe fine motor impairment.
Conclusions:
- The Bayley-III motor composite score of 85 may overestimate motor impairment in preterm infants.
- A revised cut-point may improve diagnostic accuracy.
- Further research with term-born controls and longer follow-up is recommended.
Objective:
To determine whether a Bayley-III motor composite score of 85 may overestimate moderate-severe motor impairment by analyzing Bayley-III motor components and developing cut-point scores for each.
Study Design:
Retrospective study of 1183 children born <27 weeks gestation at NICHD Neonatal Research Network centers and evaluated at 18-22 months corrected age. Gross Motor Function Classification System determined gross motor impairment. Statistical analyses included linear and logistic regression and sensitivity/specificity.
Results:
Bayley-III motor composite scores were strong indicators of gross/fine motor impairment. A motor composite cut-point of 73 markedly improved the specificity for identifying gross and/or fine motor impairment (94% compared with a specificity of 76% for the proposed new cut-point of 85). A Fine Motor Scaled Score <3 differentiated mild from moderate-severe fine motor impairment.
Conclusions:
This study indicates that a Bayley-III motor composite score of 85 may overestimate impairment. Further studies are needed employing term controls and longer follow-up.
