Extending the randomized trial with process evaluation was needed to obtain insight into associations between the components of intervention and developmental outcome. Specific therapist behaviors of parent coaching are associated with improved developmental outcome measures. Further studies are needed to examine whether these associations are caused by therapist behavior or whether therapist behavior is modified by children's motor skills.

We present a systematic review on the effect of early intervention, starting between birth and a corrected age of 18 months, on motor development in infants at high risk for, or with, developmental motor disorders. Thirty‐four studies fulfilled the selection criteria. Seventeen studies were performed within the neonatal intensive care unit (NICU) environment. Eight studies had a high methodological quality. They evaluated various forms of intervention. Results indicated that the Newborn Individualized Developmental Care and Assessment Program (NIDCAP) intervention might have a temporary positive effect on motor development. Twelve of the 17 post‐NICU studies had a high methodological quality. They addressed the effect of neurodevelopmental treatment (NDT) and specific or general developmental programmes. The results showed that intervention in accordance with the principles of NDT does not have a beneficial effect on motor development. They also indicated that specific or general developmental programmes can have a positive effect on motor outcome. We concluded that the type of intervention that might be beneficial for infants at preterm age differs from the type that is effective in infants who have reached at least term age. Preterm infants seem to benefit most from intervention that aims at mimicking the intrauterine environment, such as NIDCAP intervention. After term age, intervention by means of specific or general developmental programmes has a positive effect on motor development.

AIM The aim of this study was to examine the effects of intervention in infants at risk of developmental disorders on motor outcome, as measured by the Infant Motor Profile (IMP) and using the combined approach of a randomized controlled trial and process evaluation.METHOD At a corrected age of 3 months, 46 infants (20 males, 26 females) recruited from the neonatal intensive care unit at the University Medical Centre Groningen (median birthweight 1210g, range 585-4750g; median gestational age 30wks, range 25-40wks) were included on the basis of definitely abnormal general movements. Exclusion criteria were severe congenital disorders and insufficient understanding of the Dutch language. The infants were assigned to either the familycentred COPing with and CAring for Infants with Special Needs (COPCA) intervention group (n=21; 9 males, 12 females) or the traditional infant physiotherapy (TIP) intervention group (n=25; 11 males, 14 females) for a period of 3 months. Three infants assigned to the TIP group (one male, two females) did not receive physiotherapy. IMP scores were measured by blinded assessors at 3, 4, 5, 6, and 18 months. At each age, the infants were neurologically examined. Physiotherapeutic sessions at 4 and 6 months were videotaped. Quantified physiotherapeutic actions were correlated with IMP scores at 6 and 18 months. RESULTSThe IMP scores of both the COPCA and TIP groups before, during, and after the intervention did not differ. Some physiotherapeutic actions were associated with IMP outcomes; the associations differed for infants who developed cerebral palsy (n=10) and those who did not (n=33). INTERPRETATIONAt randomized controlled trial level, the scores of both the TIP and COPCA groups did not differ in effect on motor outcome, as measured with the IMP. The analysis of physiotherapeutic actions revealed associations between these actions and IMP outcomes. However, the small sample size of this study precludes pertinent conclusions.

We present a systematic review on the effect of early intervention, starting between birth and a corrected age of 18 months, on motor development in infants at high risk for, or with, developmental motor disorders. Thirty-four studies fulfilled the selection criteria. Seventeen studies were performed within the neonatal intensive care unit (NICU) environment. Eight studies had a high methodological quality. They evaluated various forms of intervention. Results indicated that the Newborn Individualized Developmental Care and Assessment Program (NIDCAP) intervention might have a temporary positive effect on motor development. Twelve of the 17 post-NICU studies had a high methodological quality. They addressed the effect of neurodevelopmental treatment (NDT) and specific or general developmental programmes. The results showed that intervention in accordance with the principles of NDT does not have a beneficial effect on motor development. They also indicated that specific or general developmental programmes can have a positive effect on motor outcome. We concluded that the type of intervention that might be beneficial for infants at preterm age differs from the type that is effective in infants who have reached at least term age. Preterm infants seem to benefit most from intervention that aims at mimicking the intrauterine environment, such as NIDCAP intervention. After term age, intervention by means of specific or general developmental programmes has a positive effect on motor development.