High variability of individual longitudinal motor performance over five years in very preterm infants

Res Dev Disabil. 2016 Dec:59:306-317. doi: 10.1016/j.ridd.2016.09.017. Epub 2016 Sep 23.

Abstract

Aim: To determine longitudinal motor performance in very preterm (VPT) infants from 6 months to 5 years of age for the entire cohort of infants, according to gender and gestational age and at the individual level.

Method: Single-center, prospective longitudinal study of 201 VPT infants (106 boys) without severe impairments.

Outcomes: Motor performance was assessed with the Bayley Scales of Infant Development (BSID-II-MS: 6, 12, 24 months) and the Movement Assessment Battery for Children (MABC-2-NL: 5 years).

Results: At 6, 12, and 24 months and then at 5 years, 77%, 80%, 48%, and 22% of the infants, respectively, showed delayed motor performance (<-1SD). At 5 years, girls performed significantly better than boys in manual dexterity and balance. MIXED MODEL ANALYSES: that examined interactions between time and gender and time and gestational age, revealed no significant interactions. The variance at child level was 29%. Linear mixed model analysis revealed that mean z-scores of -1.46 at 6 months of age declined significantly to -0.52 at 5 years. Individual longitudinal motor performance showed high variability.

Implications: Longitudinal motor performance improved almost 1 SD over five years. However, the variability of individual longitudinal motor performance hampers evaluation in clinical care and research.

Keywords: Longitudinal studies; Motor skills; Premature birth.

MeSH terms

  • Child Development*
  • Child, Preschool
  • Female
  • Gestational Age
  • Hand
  • Humans
  • Individuality
  • Infant
  • Infant, Extremely Premature
  • Infant, Premature
  • Linear Models
  • Longitudinal Studies
  • Male
  • Motor Skills*
  • Postural Balance*
  • Prospective Studies
  • Sex Factors