Predictive value of definitely abnormal general movements in the general population

Aim Definitely abnormal general movements in populations of high‐risk infants predict serious neurodevelopmental impairment. This study aimed to assess predictive values of definitely abnormal general movements at 3 months for serious neurodevelopmental impairment in a representative sample of the general population. Method A prospective cohort study of 455 3‐month‐old infants was performed (241 females, 214 males; mean birthweight 3452g, SD 604g; mean gestational age 39.4wks, SD 1.96; n=32 born preterm). At enrolment, general movement quality was assessed by means of video recording. At 4 years, all participants were reassessed by well‐baby health clinicians; if serious neurodevelopmental impairment was identified, clinical records were reviewed. Predictive values of definitely abnormal general movement quality for major neurodevelopmental impairment were calculated. Results Five children were diagnosed as having a major neurodevelopmental disorder with serious implications for daily life, including three children with cerebral palsy (CP). Three out of the five had shown definitely abnormal general movements; they had lesions involving the periventricular white matter. Two children did not show definitely abnormal general movements; one had unilateral spastic CP due to a cortical lesion and the other had ataxia due to cerebellar atrophy. The positive predictive value of definitely abnormal general movements for major neurodevelopmental impairment was 18/100, and for CP it was 12/100. Negative predictive values approached 100%. Interpretation The good predictive value of general movement assessment in high‐risk populations cannot be generalized to the general population.