Behavioral and Neuroimaging Research on Developmental Coordination Disorder (DCD): A Combined Systematic Review and Meta-Analysis of Recent Findings.

AIM: The neurocognitive basis of Developmental Coordination Disorder (DCD; or motor clumsiness) remains an issue of continued debate. This combined systematic review and meta-analysis provides a synthesis of recent experimental studies on the motor control, cognitive, and neural underpinnings of DCD. METHODS: The review included all published work conducted since September 2016 and up to April 2021. One-hundred papers with a DCD-Control comparison were included, with 1,374 effect sizes entered into a multi-level meta-analysis. RESULTS: The most profound deficits were shown in: voluntary gaze control during movement; cognitive-motor integration; practice-/context-dependent motor learning; internal modeling; more variable movement kinematics/kinetics; larger safety margins when locomoting, and atypical neural structure and function across sensori-motor and prefrontal regions. INTERPRETATION: Taken together, these results on DCD suggest fundamental deficits in visual-motor mapping and cognitive-motor integration, and abnormal maturation of motor networks, but also areas of pragmatic compensation for motor control deficits. Implications for current theory, future research, and evidence-based practice are discussed. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, identifier: CRD42020185444.

What do parents expect from a genetic diagnosis of their child with intellectual disability?

BACKGROUND: Caring for a child with intellectual disability (ID) has been associated with increased social and psychological burdens. Diagnostic and prognostic uncertainty may enhance emotional stress in families. METHOD: The present authors assessed the motivations, expectations, mental health, physical health and the quality of life of 194 parents whose children with intellectual disability were undergoing a genetic diagnostic workup. RESULTS: Most parents considered a diagnosis highly relevant for their own emotional relief, their child's therapies and education, or family planning. Parental mental health was significantly lower compared with the normative sample, but physical health was not different. The severity of the child's intellectual disability correlated negatively with their parents' mental and physical health, quality of life, and positively with parental anxiety. CONCLUSION: Healthcare providers should be aware of the disadvantages facing families with intellectually disabled children. Receiving practical, social and psychological support as well as genetic testing might be particularly relevant for families with severely disabled children.

International clinical practice recommendations on the definition, diagnosis, assessment, intervention, and psychosocial aspects of developmental coordination disorder.

AIM: These international clinical practice recommendations (CPR) for developmental coordination disorder (DCD), initiated by the European Academy of Childhood Disability (EACD), aim to address key questions on the definition, diagnosis, assessment, intervention, and psychosocial aspects of DCD relevant for clinical practice. METHOD: Key questions in five areas were considered through literature reviews and formal expert consensus. For recommendations based on evidence, literature searches on 'mechanisms', 'assessment', and 'intervention' were updated since the last recommendations in 2012. New searches were conducted for 'psychosocial issues' and 'adolescents/adults'. Evidence was rated according to the Oxford Centre for Evidence-Based Medicine (level of evidence [LOE] 1-4) and transferred into recommendations. For recommendations based on formal consensus, two meetings of an international, multidisciplinary expert panel were conducted with a further five Delphi rounds to develop good clinical practice (GCP) recommendations. RESULTS: Thirty-five recommendations were made. Eight were based on the evidence from literature reviews (three on 'assessment', five on 'intervention'). Twenty-two were updated from the 2012 recommendations. New recommendations relate to diagnosis and assessment (two GCPs) and psychosocial issues (three GCPs). Additionally, one new recommendation (LOE) reflects active video games as adjuncts to more traditional activity-oriented and participation-oriented interventions, and two new recommendations (one GCP, one LOE) were made for adolescents and adults with DCD. INTERPRETATION: The CPR-DCD is a comprehensive overview of DCD and current understanding based on research evidence and expert consensus. It reflects the state of the art for clinicians and scientists of varied disciplines. The international CPR-DCD may serve as a basis for national guidelines. WHAT THIS PAPER ADDS: Updated international clinical practice guidelines on developmental coordination disorder (DCD). Refined and extended recommendations on clinical assessment and intervention for DCD. A critical synopsis of current research on mechanisms of DCD. A critical synopsis of psychosocial issues in DCD, with implications for clinical practice. The first international recommendations to consider adolescents and adults with DCD.

Evaluating the evidence for motor-based interventions in developmental coordination disorder: A systematic review and meta-analysis.

BACKGROUND: As part of the process of creating an update of the clinical practice guidelines for developmental coordination disorder (DCD) (Blank, Smits-Engelsman, Polatajko, & Wilson, 2012), a systematic review of intervention studies, published since the last guidelines statement was conducted. AIM: The aim of this study was to 1) systematically review the evidence published from January 2012 to February 2017 regarding the effectiveness of motor based interventions in individuals with DCD, 2) quantify treatment effects using a meta-analysis, 3) examine the available information on different aspects of delivery including use of group intervention, duration and frequency of therapy, and 4) identify gaps in the literature and make recommendations for future intervention research. METHOD: An electronic search of 5 databases (PubMed, Embase, Pedro, Scopus and Cochrane) was conducted for studies that evaluated motor-based interventions to improve performance for individuals with DCD. RESULTS: Thirty studies covering 25 datasets were included, 19 of which provided outcomes on standardized measures of motor performance. The overall effect size (Cohen's d) across intervention studies was large (1.06), but the range was wide: for 11 interventions, the observed effect was large (>0.80), in eight studies moderate (>0.50), and in five it was small or negligible (<0.50). Positive benefits were evident for activity-oriented approaches, body function-oriented combined with activities, active video games, and small group programs. CONCLUSION: Results showed that activity-oriented and body function oriented interventions can have a positive effect on motor function and skills. However, given the varied methodological quality and the large confidence intervals of some studies, the results should be interpreted with caution.

Cognitive and neuroimaging findings in developmental coordination disorder: new insights from a systematic review of recent research.

AIM: To better understand the neural and performance factors that may underlie developmental coordination disorder (DCD), and implications for a multi-component account. METHOD: A systematic review of the experimental literature published between June 2011 and September 2016 was conducted using a modified PICOS (population, intervention, comparison, outcomes, and study type) framework. A total of 106 studies were included. RESULTS: Behavioural data from 91 studies showed a broad cluster of deficits in the anticipatory control of movement, basic processes of motor learning, and cognitive control. Importantly, however, performance issues in DCD were often shown to be moderated by task type and difficulty. As well, we saw new evidence of compensatory processes and strategies in several studies. Neuroimaging data (15 studies, including electroencephalography) showed reduced cortical thickness in the right medial orbitofrontal cortex and altered brain activation patterns across functional networks involving prefrontal, parietal, and cerebellar regions in children with DCD than those in comparison groups. Data from diffusion-weighted magnetic resonance imaging suggested reduced white matter organization involving sensorimotor structures and altered structural connectivity across the whole brain network. INTERPRETATION: Taken together, results support the hypothesis that children with DCD show differences in brain structure and function compared with typically developing children. Behaviourally, these differences may affect anticipatory planning and reduce automatization of movement skill, prompting greater reliance on slower feedback-based control and compensatory strategies. Implications for future research, theory development, and clinical practice are discussed.

Ecological validity of the German Bruininks-Oseretsky Test of Motor Proficiency - 2nd Edition.

The diagnosis of Developmental Coordination Disorder (DCD) is based on poor motor coordination in the absence of other neurological disorders. In order to identify the presence of movement difficulties, a standardised motor assessment is recommended to determine the extent of movement problems which may contribute to deficits in daily task performance. A German version of the Bruininks-Oseretsky Test of Motor Proficiency, Second Edition (German BOT-2) was recently published. This study aimed to determine the ecological validity of the German BOT-2 by considering the relationship between assessment of fundamental motor skills with the BOT-2 and performance of everyday motor activities as evaluated by parents. This study used data obtained from the German BOT-2 standardisation study (n=1.177). Subtests were compared with theoretically corresponding tasks via parental ratings of overall fine and gross motor abilities and performance in six typical motor activities. Non-parametric Jonckheere Terpstra test was used to identify differences in ordered contrasts. Subtests reflecting 'Strength', 'Running Speed and Agility', 'Upper-Limb Coordination', 'Balance', and 'Fine Motor Precision' were associated with parental evaluation of gross motor skills (p<0.001). The subtest 'Fine Motor Integration' significantly correlated with parental ratings of females' fine motor skills. Parental ratings of males' fine motor skills were associated with three further subtests. Regarding everyday motor activities, the first three fine motor BOT-2 subtests were associated with parent evaluations of drawing, writing and arts and crafts (p<0.001). Gross motor subtests of 'Bilateral Coordination' and 'Balance' showed no relationship to bike riding or performance in sports. Subtests of 'Upper-Limb Coordination' and 'Strength' showed significant correlations with sports, ball games and cycling. The results of this study suggest that the closer the proximity in the nature of the motor skills assessed in the German BOT-2 to daily motor tasks, the stronger the relationship between the clinical test and parental report of everyday performance of their child. The body functions tested in the German BOT-2, and hypothesized to underpin certain skills, were not automatically relevant for specific activities undertaken by German children. Future research should investigate the relationships of the various BOT-2 constructs for diagnosis of DCD.

[Autism Spectrum Disorder and DSM-5: Spectrum or Cluster?]. / Autistische Störungen nach DSM-5: Spektrum oder Cluster?

Within the new DSM-5, the currently differentiated subgroups of "Autistic Disorder" (299.0), "Asperger's Disorder" (299.80) and "Pervasive Developmental Disorder" (299.80) are replaced by the more general "Autism Spectrum Disorder". With regard to a patient-oriented and expedient advising therapy planning, however, the issue of an empirically reproducible and clinically feasible differentiation into subgroups must still be raised. Based on two Autism-rating-scales (ASDS and FSK), an exploratory two-step cluster analysis was conducted with N=103 children (age: 5-18) seen in our social-pediatric health care centre to examine potentially autistic symptoms. In the two-cluster solution of both rating scales, mainly the problems in social communication grouped the children into a cluster "with communication problems" (51 % and 41 %), and a cluster "without communication problems". Within the three-cluster solution of the ASDS, sensory hypersensitivity, cleaving to routines and social-communicative problems generated an "autistic" subgroup (22%). The children of the second cluster ("communication problems", 35%) were only described by social-communicative problems, and the third group did not show any problems (38%). In the three-cluster solution of the FSK, the "autistic cluster" of the two-cluster solution differentiated in a subgroup with mainly social-communicative problems (cluster 1) and a second subgroup described by restrictive, repetitive behavior. The different cluster solutions will be discussed with a view to the new DSM-5 diagnostic criteria, for following studies a further specification of some of the ASDS and FSK items could be helpful.

Behavioral phenotype in five individuals with de novo mutations within the GRIN2B gene.

BACKGROUND: Intellectual disability (ID) is often associated with behavioral problems or disorders. Mutations in the GRIN2B gene (MRD6, MIM613970) have been identified as a common cause of ID (prevalence of 0.5 - 1% in individuals with ID) associated with EEG and behavioral problems. METHODS: We assessed five GRIN2B mutation carriers aged between 3 and 14 years clinically and via standardized questionnaires to delineate a detailed behavioral phenotype. Parents and teachers rated problem behavior of their affected children by completing the Developmental Behavior Checklist (DBC) and the Conners' Rating Scales Revised (CRS-R:L). RESULTS: All individuals had mild to severe ID and needed guidance in daily routine. They showed characteristic behavior problems with prominent hyperactivity, impulsivity, distractibility and a short attention span. Stereotypies, sleeping problems and a friendly but boundless social behavior were commonly reported. CONCLUSION: Our observations provide an initial delineation of the behavioral phenotype of GRIN2B mutation carriers.

Efficacy of interventions to improve motor performance in children with developmental coordination disorder: a combined systematic review and meta-analysis.

AIM: The aim of this study was to review systematically evidence about the efficacy of motor interventions for children with developmental coordination disorder (DCD), and to quantify treatment effects using meta-analysis. METHOD: Included were all studies published between 1995 and 2011 that described a systematic review, (randomized) clinical trial, or crossover design about the effect of motor intervention in children with DCD. Studies were compared on four components: design, methodological quality, intervention components, and efficacy. Twenty-six studies met the inclusion criteria for the review. Interventions were coded under four types: (1) task-oriented intervention, (2) traditional physical therapy and occupational therapy, (3) process-oriented therapies, and (4) chemical supplements. For the meta-analysis, effect sizes were available for 20 studies and their magnitude (weighted Cohen's d [d(w) ]) was compared across training types. RESULTS: The overall effect size across all intervention studies was d(w) =0.56. A comparison between classes of intervention showed strong effects for task-oriented intervention (d(w) =0.89) and physical and occupational therapies (d(w) =0.83), whereas that for process-oriented intervention was weak (d(w) =0.12). Of the chemical supplements, treatment with methylphenidate was researched in three studies (d(w) =0.79) and supplementation of fatty acids plus vitamin E in one study (no effect). The post hoc comparison between treatment types showed that the effect size of the task-oriented approach was significantly higher than the process-oriented intervention (p=0.01) and comparison (p=0.006). No significant difference in the magnitude of effect size between traditional physical and occupational therapy approaches and any of the other interventions emerged. INTERPRETATION: In general, intervention is shown to produce benefit for the motor performance of children with DCD, over and above no intervention. However, approaches from a task-oriented perspective yield stronger effects. Process-oriented approaches are not recommended for improving motor performance in DCD, whereas the evidence for chemical supplements for children with DCD is currently insufficient for a recommendation.

Understanding performance deficits in developmental coordination disorder: a meta-analysis of recent research.

AIM: Developmental coordination disorder (DCD) is a significant disorder of childhood, characterized by core difficulties in learning fine and/or gross motor skills, and the attendant psychosocial problems. The aim of the meta-analysis presented here (the first on DCD since 1998) was to summarize trends in the literature over the past 14 years and to identify and describe the main motor control and cognitive deficits that best discriminate children with DCD from those without. METHOD: A systematic review of the literature published between January 1997 and August 2011 was conducted. All available journal papers reporting a comparison between a group of children with DCD and a group of typically developing children on behavioural measures were included. RESULTS: One hundred and twenty-nine studies yielded 1785 effect sizes based on a total of 2797 children with DCD and 3407 typically developing children. Across all outcome measures, a moderate to large effect size was found, suggesting a generalized performance deficit in children with DCD. The pattern of deficits suggested several areas of pronounced difficulty, including internal (forward) modelling, rhythmic coordination, executive function, gait and postural control, catching and interceptive action, and aspects of sensoriperceptual function. INTERPRETATION: The results suggest that the predictive control of action may be a fundamental disruption in DCD, along with the ability to develop stable coordination patterns. Implications for theory development and intervention are discussed.

The development of the fastest isometric grip force changes and clinical relevance.

Fast force changes with hand-held objects are an important prerequisite for object manipulation in everyday life. This study examines the development of fastest isometric force changes in a precision grip. One hundred sixty-five children (76 girls, 89 boys), 3-14 years, without neurological abnormalities increased and decreased repetitively isometric grip forces as rapidly as possible by their dominant hand using a small cylindrical pinch grip object (20 g). The frequency of repetitive force changes increased in a linear way from the age of 4 years until about 12 years by 0.23 Hz per year (r2 = .54) without noticeable gender difference. The ratio of the duration of force increase and decrease slightly declined from 1.05 (4-year-olds) to 0.95 (11- to 14-year-olds). The development of force amplitudes and the mean force were more variable. Temporal parameters become less variable with age, whereas force parameters become more variable. In particular, the temporal parameters of fastest isometric force changes are best predictors for developmental changes. Fastest isometric force changes may be an important basic capacity for fast object manipulation, particularly in young children and in children with movement disorders.

Subjective well-being and satisfaction with life in adults with spastic cerebral palsy: a pilot study of a randomized sample.

The aim of this study was to explore subjective well-being and satisfaction with life in general and with participation, activities, and health, in adults with cerebral palsy (CP). A randomized sample of 50 individuals was drawn from a sample of 465 previous outpatients of a regional social paediatric centre in southern Germany. A psychological measure for well-being (Bern Questionnaire on Subjective Well-Being, adult form [BSW/A]) and a sociomedical measure (Life Satisfaction Checklist [LiSat-11]) were applied as outcome measures. Twenty-five individuals from 35 responders (nine males, 16 females; mean age 28y, SD 2y 7mo, range 25-33y) were evaluated completely. Nineteen participants had bilateral and six had unilateral spastic types of CP (Gross Motor Function Classification System Levels I n=5, II n=5, III n=5, IV n=8, and V n=2). Eighteen individuals had no or only minor intellectual disabilities. Subjective well-being and general satisfaction with life were not impaired in adults with CP. Joy of life (a subscale of the BSW/A) was even increased. Satisfaction with some areas of participation was reduced compared with a reference and clinical samples from Sweden. In conclusion, subjective well-being and general satisfaction with life are not decreased in adults with CP. The different levels of satisfaction with areas of participation in German and Swedish individuals with CP may be explained by differences of social inclusion.

Conductive education for children with cerebral palsy: effects on hand motor functions relevant to activities of daily living.

OBJECTIVE: To study the effects of conductive education, a combined educational and therapeutic task-oriented approach for children with cerebral palsy (CP), on their hand motor functions and activities of daily living (ADLs). DESIGN: Individual cohort study (B-A-B design). SETTING: Ambulatory, referral center. PARTICIPANTS: Sixty-four children with CP, severity Gross Motor Function Classification System levels II through IV, ages 3 to 6 years. INTERVENTIONS: Phases B: a 4.5-month period of special education, including 2 hours of individual physiotherapy or occupational therapy per week (special education). Phase A: during a 9-month period, conductive education was administered in 3 blocks of 4 weeks (7 hours daily from Monday through Friday); between the blocks, special education was applied as in the B phases. MAIN OUTCOME MEASURES: Transformed sum scores (0.00-1.00) for coordinative (eg, force-movement synergy during object manipulation, aiming) and for elementary hand functions (eg, maximum grip force, tapping), based on kinetic and kinematic measures; standardized parent questionnaire to measure ADL competence scores from 0.00 (dependence) to 1.00 (independence). Outcome parameters were changes in these parameters during phase A (intervention) compared with average changes during the B phases (pre- and postintervention). Student t tests were used for dependent samples. RESULTS: Conductive education improved coordinative hand functions by 20% to 25% from baseline, compared with no improvement during special education; the preferred hand improved from .38 to .48 (mean, .10; 95% confidence interval [CI], .086-.114) and the nonpreferred hand improved from .39 to .47 (mean, .08; 95% CI, .034-.116). There were no changes in elementary hand motor functions. ADL competence improved by .11 (95% CI, .070-.149), from .50 to .61 ( approximately 20%), compared with no significant improvement under special education. CONCLUSIONS: Conductive education improved coordinative hand functions and ADLs in children with CP. There was no effect on elementary hand functions.

Hyperkinetic Syndrome: The role of allergy among psychological and neurological factors.

The role of allergies was examined in a clinical sample of 122 successive referrals with suspected Hyperkinetic Syndrome (HKS). The children were examined using general psychiatric, neurological and immunologic measures. According to these examinations, 18 of the 122 children (15%) did not meet the criteria for a diagnosis of HKS. These children served as a small comparison group since healthy children could not be examined for ethical reasons. A history of allergies was more often positive in children with HKS without associated disorders (50%) and in children with HKS and developmental retardations (36%) than in children with HKS and conduct disorders (23%) and the comparsion group (17%). The objective immunologic measures which essentially covered IgE-mediated reactions were not significantly different. These results are discussed on the background of delayed non-IgE-mediated reactions and possible psychosocial influences. There were no significant correlations between the neurological and psychiatric measures on the one hand and immunologic measures on the other. Factor analysis on the basis of the applied measures revealed three main dimensions but none of these could be interpreted as distinctive "immunologic" dimension.