Motor Optimality Scores are significantly lower in a population of high-risk infants than in infants born moderate-late preterm

Background: The Motor Optimality Score-Revised (MOS-R) is a detailed scoring of the General Movement Assessment (GMA), measuring the spontaneous behaviors of infants. Infants born moderate-late preterm are not traditionally followed in high-risk clinics, but have increased risk of neurodevelopmental disability.

Aims: Compare MOS-R at 3 months corrected age (CA) in high-risk (HR; very preterm or abnormal neuroimaging) infants to infants born moderate-late preterm (MLP).

Study design: In this prospective cohort study, parents of enrolled infants created video recordings using an app at 3 months CA. Videos were scored with the General Movement Assessment (GMA) and MOS-R. MOS-R scores were divided into "higher-risk" (≤19) and "lower-risk" (≥20).

Subjects: 181 infants born MLP or categorized as HR.

Results: Among enrolled infants, 68 (38 %) were in the MLP group, and 113 infants were in the HR group. The HR group had 3.8 increased odds of having an aberrant GMA score compared to the MLP group (p < 0.01, 95 % CI 1.38-10.52). The HR group had significantly lower MOS-R scores (mean 20) than the MLP group (mean 24; p < 0.001; 95%CI 3.3-7.3). The HR group had 11.2 increased odds of having a higher-risk MOS-R score (95%CI 2.5-47.6, p < 0.001) than MLP group. Infants were most likely to have a lower MOS-R score if they had any of the following: VP shunt placement, periventricular leukomalacia, or bronchopulmonary dysplasia.

Conclusions: Aberrant GMA and higher-risk MOS-R scores were more common in infants at high-risk, reflecting history of brain lesions and younger gestational age at birth.