Background: Preterm infants and infants with perinatal brain injury show higher incidence of neurodevelopmental disorders (NDD). The Infant Motor Profile (IMP) is a clinical assessment which evaluates the complexity of early motor behaviour. More data are needed to confirm its predictive ability and concurrent validity with other common and valid assessments such as the Alberta Infant Motor Profile (AIMS) and the Prechtl’s General Movement Assessment (GMA). The present study aims to evaluate the concurrent validity of IMP with AIMS, to assess its association with GMA, to evaluate how IMP reflects the severity of the brain injury and to compare the ability of IMP and AIMS to predict abnormal outcome in 5-months infants at risk of NDD.
Methods: 86 infants at risk of NDD were retrospectively recruited among the participants of two clinical trials. Preterm infants with or without perinatal brain injury and term infants with brain injury were assessed at 3 months corrected age (CA) using GMA and at 5 months CA using IMP and AIMS. Neurodevelopmental outcome was established at 18 months.
Results: Results confirm a solid concurrent validity between IMP and AIMS (Spearman’s ρ 0.76; p<.001) and significant association between IMP and GMA. Unlike AIMS, IMP Total score accurately reflects the severity of neonatal brain injury (p<.001) and results to be the strongest predictor of NDD (p<.001). Confrontation of areas under receiver operating characteristic curves (AUC) confirms that IMP Total score has the highest diagnostic accuracy at 5 months (AUC 0.92). For an optimal IMP cut-off value of 70, the assessment shows high sensitivity (93%) and specificity (81%) (PPV 84%; NPV 90%).
Conclusions: Early motor behaviour assessed with IMP is strongly associated with middle-term neurodevelopmental outcome. The present study confirms the concurrent validity of IMP with AIMS, its association with GMA and its ability to reflect brain lesion load contributing to the construct validity of the assessment.
Trial registration: NCT01990183 and NCT03234959 (clinicaltrials.gov)