Marina M. Schoemaker

Clinical and research diagnostic criteria for developmental coordination disorder: a review and discussion

The aim of this review was to investigate the selection criteria used in the past in studies of children with developmental motor problems (excluding those suffering from neurological dysfunctions such as cerebral palsy, muscular dystrophy, etc.). We therefore conducted an extensive analysis of 176 publications. First, an overview of the main characteristics of these studies (terminology, population, type and purpose) and the selection criteria that are reported in these publications are presented. Following this, the DSM-IV selection criteria for developmental coordination disorder (DCD) are contrasted with the selection criteria reported in 41 publications that have used this terminology to classify the children. The results of this comparison show that the inclusion criteria are largely followed, albeit with little consistency concerning selection instruments and quantitative cut-offs, while adherence to the exclusion criteria is not common practice. Strengths and weaknesses of the DSM-IV criteria, complementary to the previous discussion by Henderson and Barnett in the HMS special issue on DCD in 1998 on this same topic, are discussed. The results of the review also show that many studies have used additional selection criteria related to the specific research questions of the study concerned. In the broader context of clinical practice as well as basic research, the latter result suggests the usefulness of a distinction between Clinical Diagnostic Criteria and Research Diagnostic Criteria. This distinction helps to develop a unifying view on the use of diagnostic criteria for research and clinical practice. We conclude with a number of recommendations concerning the selection criteria for children with DCD.

Capacity, Capability, and Performance: Different Constructs or Three of a Kind?

OBJECTIVES The present study focused on motor activities of young children with cerebral palsy (CP) and examined the relation between motor capacity (what a person can do in a standardized, controlled environment), motor capability (what a person can do in his/her daily environment), and motor performance (what a person actually does do in his/her daily environment). DESIGN The relations between motor capacity, motor capability, and motor performance were calculated by using Pearson correlations and visualized by scatterplots. SETTING A cross-sectional study of a hospital-based population of children with CP. PARTICIPANTS Subjects were children with CP (N=85) aged 30 months (Gross Motor Function Classification System levels I-V). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Motor capacity, motor capability, and motor performance were assessed with the Gross Motor Function Measure and 2 scales of the Pediatric Evaluation of Disability Inventory, respectively. RESULTS Correlations between motor capacity, motor capability, and motor performance were high, between 0.84 and 0.92, and significant (P< .001). But when comparing children with the same level of motor capacity or motor capability, large ranges at the level of motor performance were found. CONCLUSIONS Results imply that motor performance levels are only partly reflected by the motor capacity and motor capability levels in young children children with CP. Contextual factors (physical and social environment) and personal factors (such as motivation) influence the relations between capacity, capability, and performance. This information is essential in making decisions about the focus of therapy to maximize a childs independent functioning in daily life.

Fine motor skills and effects of methylphenidate in children with attention-deficit–hyperactivity disorder and developmental coordination disorder

The aims of this study were to investigate fine motor skills of children with both attention‐deficit–hyperactivity disorder (ADHD) and developmental coordination disorder (DCD) and those of a control group, and to examine the effects of methylphenidate on these skills. A group of 12 children with ADHD–DCD (11 males, one female; mean age 9y 8mo [SD 1y 7mo]) and 12 age‐ and sex‐matched controls (mean age 9y 7mo [SD 1y 2 mo]) participated. The manual dexterity subtests of the Movement Assessment Battery for Children, the concise assessment method for childrens handwriting, and a computerized graphomotor task were used. Results demonstrated that children with ADHD–DCD performed more poorly on the manual dexterity subtests, had poorer quality of handwriting, and drew more rapidly, more fluently, but less accurately than controls on the graphomotor task. On methylphenidate, manual dexterity and quality of handwriting improved, and strokes on the graphomotor task became less fluent but more accurate. ADHD is characterized by persistent symptoms of inattention, impulsivity, and hyperactivity, affecting 3 to 5% of school‐age children. Up to 50% of children with ADHD also have motor coordination problems that are severe enough to meet criteria for DCD. In DCD, children demonstrate functional motor performance deficits not explained by the childs (chronological) age or intellect, or by other neurological or psychiatric disorders

Physiotherapy for clumsy children: an evaluation study.

This study reports the findings of an effect‐evaluation study of physiotherapy for clumsy children. 18 children were identified by school doctors as having poor motor co‐ordination. They were followed for three months in order to exclude spontaneous improvement of motor problems; none spontaneously improved. Subsequently, these children were enrolled on a regular physiotherapy programme. Treatment was administered individually twice a week over three months. The effects of treatment for clumsy children appeared to be promising: important improvements were found on various motor skills. These benefits were maintained for a three‐month period after the end of treatment.

Consequences of Comorbidity of Developmental Coordination Disorders and Learning Disabilities for Severity and Pattern of Perceptual—Motor Dysfunction

Children with developmental coordination disorder (DCD) have difficulty learning and performing age-appropriate perceptual—motor skills in the absence of diagnosable neurological disorders. Descriptive studies have shown that comorbidity of DCD exists with attentiondeficit/hyperactivity disorder (ADHD) and learning disabilities (LD). This study examined the consequences of the comorbidity of DCD and LD for the severity and pattern of perceptual—motor dysfunction. Compared to children with DCD without LD, children with co-morbid DCD and LD performed lower on a standardized assessment of perceptual—motor ability. Furthermore, it appeared that children with combined DCD and LD have particular difficulty performing manual dexterity and balance tasks but not ball-skill tasks. Implications for understanding the relationship between LD and perceptual—motor problems are discussed. We conclude that the comorbidity of DCD and LD not only affects the severity of perceptual—motor dysfunction but also is associated with a distinctive pattern of perceptual—motor dysfunction.

Evaluation of the Developmental Coordination Disorder Questionnaire as a screening instrument

Reliability and validity of the Developmental Coordination Disorder Questionnaire (DCD-Q) was assessed using a population-based sample of 608 children (311 males, 297 females; mean age 7 y 8 mo [SD 2 y 4 mo]), a sample of 55 children with DCD referred to a rehabilitation clinic, and a control sample of 55 children matched for age and sex (48 males, seven females in each sample; mean age 8 y 3 mo [SD 2 y]). The DCD-Q is reliable and valid in the age range for which the questionnaire was developed(8 y-14 y 7 mo) and in a younger age range (4-8 y). Sensitivity and specificity of the DCD-Q was assessed using the Movement Assessment Battery for Children as the criterion standard. The DCD-Q met the standard for sensitivity (80%) in the clinic-referred sample (81.6%), but not in the population-based sample (28.9%). Specificity almost reached the standard of 90%: 89% in the population-based sample and 84% in the clinic-referred sample.

Neuromotor task training for children with developmental coordination disorder: a controlled trial

The aim of this study was to evaluate neuromotor task training (NTT), a recently developed child‐centred and task‐oriented treatment programme for children with developmental coordination disorder (DCD). A treatment and a non‐treatment control group of children with DCD were included. Children were selected if they scored below the 15th centile on the Movement Assessment Battery for Children (MABC). The children in the treatment group were recently referred for physiotherapy (n=26; 20 males, 6 females; mean age 7y 2mo [SD 1y 3mo]). The parents of the non‐treated children were concerned about their childrens motor performance and responded to advertisements for free testing (n=13; 10 males, 3 females; mean age 7y 2mo [SD 2y 1mo]). Before and after nine weekly 30‐minute sessions of NTT or at least 9 weeks of no intervention, the MABC and the Test of Gross Motor Development ‐ 2 (TGMD‐2) were administered. Therapists reported per session on treatment goals and tasks trained. The results indicate that motor performance does not improve spontaneously and that NTT is effective. During the intervention period, only the treated group improved on the MABC and the TGMD‐2. Children improved most on tasks similar to those trained. In older children with poorer motor patterns, NTTs treatment success was higher. The Child Behavior Checklist subscales withdrawn, thought problems, anxious/depressed, and delinquency were determinants of effects on motor patterns.

What is the evidence of impaired motor skills and motor control among children with attention deficit hyperactivity disorder (ADHD)? Systematic review of the literature

This article presents a review of the studies that have analysed the motor skills of ADHD children without medication and the influence of medication on their motor skills. The following two questions guided the study: What is the evidence of impairment of motor skills and aspects of motor control among children with ADHD aged between 6 and 16 years? What are the effects of ADHD medication on motor skills and motor control? The following keywords were introduced in the main databases: attention disorder and/or ADHD, motor skills and/or handwriting, children, medication. Of the 45 articles retrieved, 30 described motor skills of children with ADHD and 15 articles analysed the influence of ADHD medication on motor skills and motor control. More than half of the children with ADHD have difficulties with gross and fine motor skills. The children with ADHD inattentive subtype seem to present more impairment of fine motor skills, slow reaction time, and online motor control during complex tasks. The proportion of children with ADHD who improved their motor skills to the normal range by using medication varied from 28% to 67% between studies. The children who still show motor deficit while on medication might meet the diagnostic criteria of developmental coordination disorder (DCD). It is important to assess motor skills among children with ADHD because of the risk of reduced participation in activities of daily living that require motor coordination and attention.

Deficits in motor control processes involved in production of graphic movements of children with attention-deficit-hyperactivity disorder.

This study aimed to investigate whether two distinct motor control processes, i.e. motor planning and parameter setting, were impaired in children with attention-deficit-hyperactivity disorder (ADHD). An experiment was designed in which children copied figures of increasing complexity under increasing accuracy levels on a digitizer. Sixteen children with ADHD (11 males, 5 females; mean age 8 y 4 mo, SD 1 y 1 mo) and 16 comparison children, without impairment, matched for age and sex participated. ADHD was diagnosed by a psychiatrist following the criteria of the DSM-V. Only children with IQ scores greater than 80 were included. Across all graphic tasks, children with ADHD made slower, inaccurate strokes with relatively high axial pen force compared with the comparison group. No evidence was found for a deficit in motor planning, but parameter setting appeared to be deficient as the ADHD group made less accurate strokes when accuracy demands increased.

Psychometric properties of the movement assessment battery for children-checklist as a screening instrument for children with a developmental co-ordination disorder.

BACKGROUND The Checklist of the Movement Assessment Battery for Children (M-ABC) was developed to screen children for movement difficulties in the school situation. However, the psychometric properties of the Checklist have not been investigated in detail. AIM The psychometric properties of the M-ABC Checklist were investigated including its usefulness as a screening instrument. SAMPLES A group of 120 children, 6 to 11 years old, randomly selected from mainstream schools and a group of 64 children, 6 to 9 years old, referred for assessment of their motor functioning. METHODS A reliability analysis was performed to investigate whether the 48 items of the Checklist measure the same construct. Construct validity was investigated by means of a factor analysis. And lastly, the sensitivity, specificity and positive predictive value of the Checklist were investigated by comparing the performance of children on both the Test and Checklist of the M-ABC. RESULTS The items of the Checklist measure the same construct. Seven factors were obtained after factor analysis, revealing that the Checklist measures a broad range of motor skills. The Checklist met the standards for sensitivity in all age groups, except in the 8-year-old group, where too many children with motor problems were not detected. With the exception of the 6-year-old children, specificity was poor. The positive predictive value was acceptable, except for the 7-year-old children. CONCLUSION The Checklist proved to meet standards for reliability and most aspects of validity. Its use by teachers for screening children with movement difficulties can be recommended.