Seminar 2 –
University of Utrecht, Netherlands
Assessment of atypical motor development trajectories: the challenges of identifying children with DCD at a young(er) age
Early identification of children with DCD: do we have to?
It appears from the literature that the lower age limit of children with DCD included in descriptive or experimental studies (including intervention studies) is currently 6 years of age (Geuze et al., 2001). However, when interviewing parents of children with DCD about the natural history of their child’s motor coordination problems most report these to have been present already before the child entered school (Pless et al., 2001). And indeed, why assume that motor coordination problems only ‘emerge’ at (pre)school entry? It is obvious that there are already many task and environmental demands put on preschool children in order for those with non-optimal motor behaviour to be noticed (Chambers & Sugden, 2002; Jongmans, 2005). Theoretical support for this assumption is found, for example, in the connectionist approach toward development. In contrast to a modular, fixed approach, this theory assumes that (genetic) abnormalities early in life lead to low-level variations in neural organisation that cascade over time into unique and potentially uneven (cognitive, motor, social, etc.) profiles. The challenge is, therefore, to detect these abnormalities early in life in order to try to prevent them from impacting on a child’s subsequent motor development.
Identifying children with DCD at a young age: what are the challenges?
Inter- and intra-individual variability in motor performance are major challenges in identifying children with poor motor coordination at a young age. Longitudinal research among infants between 9 and 21 months has shown intra-individual fluctuations in infants’ scores over time within the gross and fine motor domain. Both periods of ‘leaps and bounces’ and periods in which children gain motor skills in steady increments can be observed. In addition, different children show different pathways to master motor skills (Darrah et al., 2003) although preferred patterns can be detected. Both phenomena carry with them the risk to either wrongly identify a child as being delayed in acquiring motor skills or to underestimate the consequences of deviant motor behaviour at an early age.
As a result, population screening methods to identify children with motor coordination difficulties have so far not been widely introduced. However, screening methods could be beneficial as they allow for identification of ‘true positive’ cases which, in turn, will facilitate early intervention. Nevertheless, it appears that the large majority of existing motor development screening instruments lack the psychometric properties needed to reach an appropriate level of sensitivity and specificity.
Identifying children with DCD at a young age: what signs to look for?
Two sources are currently available to compile a list of possible signs of motor coordination problems. First, studies looking for the underlying mechanisms of DCD point to several, although not present in all children with DCD, signs. These are: poor kinaesthetic acuity, poor visual perception, poor static balance and postural control, loss of information from visual-spatial short-term or working memory, poor attentional control, reduced strength and enhanced co-activation of muscles, slow movement preparation, enhanced spatial and temporal variability and, finally, slow feedback processing (Geuze, 2005).
The second source of information comes from retrospective descriptions of parents of children with DCD (Pless et al., 2001). These signs represent more functional activities of daily living such as a child’s quality of performance during play, sport, locomotion, meals and dressing at preschool age. Which (combination of) signs when present at preschool age will lead to DCD is currently not known. Moreover, ways of assessing these signs reliably in early childhood is still a major challenge.
While several sources indicate that children with DCD do not ´suddenly´ develop motor difficulties at school entrance, serious attempts at identifying these children before the age of 4 years are currently lacking. Although there are indications what signs to look for, due to the large intra- and inter-individual variability in developmental motor trajectories screening is still difficult. The major challenge for early identification is to extrapolate the findings from studies on older children with DCD and implement these in a reliable way at an earlier developmental stage.
- Chambers, M., & Sugden, D. (2002). The identification and assessment of young children with movement difficulties: International Journal of Early Years Education, 10, 157-176.
- Darrah, J., Hodge, M., Magill-Evans, J., et al. (2003). Stability of serial assessments of motor and communication abilities in typically developing infants – implications for screening: Early Human Development, 72, 97-110.
- Geuze, R.H. (2005). Motor impairment in DCD and activities of daily living. In D. Sugden & M. Chambers (Eds.), Children with Developmental Coordination Disorder (pp. 19-46). London: Whurr Publishers, Ltd.
- Geuze, R.H., Jongmans, M.J., Schoemaker, M.M., & Smits-Engelsman, B.C.M. (2001). Clinical and research diagnostic criteria for Developmental Coordination Disorder; a review and discussion. Human Movement Science, 20, 7-47.
- Jongmans, M.J. (2005). Early identification of children with Developmental Coordination Disorder. In D. Sugden & M. Chambers (Eds.), Children with Developmental Coordination Disorder (pp. 155-167). London: Whurr Publishers, Ltd.
- Pless, M., Persson, K., Sundelin, C., et al. (2001). Children with Developmental Coordination Disorder: a qualitative study of parents’ descriptions. Advances in Physiotherapy, 3, 128-135.