Predictive validity of a qualitative and quantitative Prechtl's General Movements Assessment at term age: Comparison between preterm infants and term infants with HIE

Abstract

AimTo determine (1) if the General Movement Optimality Score (GMOS) at term age enhances prediction of motor impairment at 12 and 24 months of age in high-risk infants, when compared to a global General Movement Assessment (GMA), and (2) compare predictive validity for two high-risk populations: infants born preterm and infants born at term with hypoxic ischaemic encephalopathy who have received therapeutic hypothermia. MethodsFifty-nine extremely preterm or term age infants with hypoxic ischaemic encephalopathy underwent term age GMA. A GMA score of normal or abnormal, and a comparative numerical General Movement Optimality Score (GMOS, total values 5–42) were assigned. Neurology and motor assessment were carried out at age 12 and 24 months using standardised assessments; Alberta Infant Motor Scale, Bayley Scales of Infant and Toddler Development or Ages and Stages Questionnaire. Outcomes were recorded as normal, motor delayed or cerebral palsy. Motor outcome prediction at 12 and 24 months of age was calculated using the GMA and, using ROC analysis, GMOS cut-off scores were determined. ResultsAt 12 and 24 months global GMA sensitivity for preterms was 80% and 100%, and for Term HIE was 100% at both ages. Specificity values for preterm infants at 12 and 24 months were 68.8% and 60% versus 28.8% and 21.4% for term HIE. Median GMOS scores were lower in the term HIE group than the preterm group in the normal and poor repertoire categories. Optimality cut off scores enhanced specificity, but values remained low. InterpretationAt term age, specificity for identification of infants with later normal motor outcome is low. The GMOS may assist identification of infants with the highest probability of motor impairment, enabling targeted intervention during critical periods for neuroplasticity.