Inter-rater reliability and test-retest reliability of the Performance and Fitness (PERF-FIT) test battery for children: a test for motor skill related fitness.

BACKGROUND: The Performance and Fitness (PERF-FIT) test battery for children is a recently developed, valid assessment tool for measuring motor skill-related physical fitness in 5 to 12-year-old children living in low-income settings. The aim of this study was to determine: (1) inter-rater reliability and (2) test-retest reliability of the PERF-FIT in children from 3 different countries (Ghana, South Africa and the Netherlands). METHOD: For inter-rater reliability 29 children, (16 boys and 13 girls, 6-10 years) were scored by 2 raters simultaneously. For test-retest reliability 72 children, (33 boys and 39 girls, 5-12 years) performed the test twice, minimally 1 week and maximally 2 weeks apart. Relative and absolute reliability indices were calculated. ANOVA was used to examine differences between the three assessor teams in the three countries. RESULTS: The PERF-FIT demonstrated excellent inter-rater reliability (ICC, 0.99) and good test-retest reliability (ICC, ≥ 0.80) for 11 of the 12 tasks, with a poor ICC for the Jumping item, due to low spread in values. A significant difference between first and second test occasion was present on half of the items, but the differences were small (Cohen's d 0.01-0.17), except for Stepping, Side jump and Bouncing and Catching (Cohen's d 0.34, 0.41 and 0.33, respectively). Overall, measurement error, Limits of Agreement and Coefficient of Variation had acceptable levels to support clinical use. No systematic dissimilarities in error were found between first and second measurement between the three countries but for one item (Overhead throw). CONCLUSIONS: The PERF-FIT can reliably measure motor skill related fitness in 5 to 12-year-old children in different settings and help clinicians monitor levels of fundamental motor skills (throwing, bouncing, catching, jumping, hopping and balance), power and agility.

Feasibility and content validity of the PERF-FIT test battery to assess movement skills, agility and power among children in low-resource settings.

BACKGROUND: Numerous movement skills and physical fitness tests have been developed for children in high-income countries. However, adaptation of these tests to low-resource settings has been slow and norms are still unavailable for children living in low-income communities. The aim of this paper was to describe the development and validation of the Performance and Fitness (PERF-FIT) test battery, a new test to assess motor skill-related physical fitness in children in low-resource settings. METHOD: The PERF-FIT test was developed in a stepwise manner. This involved defining the relevant domains of the construct of interest and selecting and evaluating test items. The Content Validity Index (CVI) was used to estimate content validity. Following development of the PERF-FIT test, a preliminary study was performed to validate items and to examine the feasibility of implementing the test in a low-resource community. Structural validity was also determined based on data from eighty (n = 80) children (aged 7-12 years) using principal component analysis. RESULTS: The CVI for the throw and catch item was 0.86 and 1.00 for the other nine items, leading to a total CVI score of 0.99. The hierarchical sequence of the item series was demonstrated by highly significant (p < 0.001) linear trends, confirming the increase in difficulty of subsequent items. Principal component analysis revealed three factors; the first component is represented by locomotor skills that require static and dynamic balance, the second component by throwing and catching items and the third component by agility and power items. These findings suggest that it is feasible to implement the PERF-FIT in low-resource settings. CONCLUSION: The PERF-FIT test battery is easy to administer and may be suitable for measuring skill-related physical fitness in in low-resource settings. It has excellent content validity and good structural validity. After minor adaptions, further studies should be conducted to establish normative values, evaluate reliability, and document criterion and cross-cultural validity of this test.

Anticipatory postural adjustment deficits in children with developmental coordination disorder during a self-induced prehension task while standing on one leg.

Effective postural control is essential for motor skill development, yet the specific nature of anticipatory control in children with Developmental Coordination Disorder (DCD) remains poorly understood for complex or dynamic stability tasks. This study investigated anticipatory postural adjustments (APA) during a self-initiated dynamic stability task. The Can Placement Task (CPT)-a self-initiated dynamic stability task-was performed by 23 children with DCD and 30 typically developing (TD) children aged 9-12 years. The task involved standing on one leg while also repositioning a can on the floor. Center of pressure (COP) movement was recorded by two force platforms during the five phases of the movement. The ground reaction force measured external support during both descent to pick up the can and ascent after replacing the can. The study used a mixed-design approach with group (DCD, TD) as a between-subject factor and condition (can position close or far) and phase of movement as within-subject. Distinct movement control characteristics were shown for children with DCD including a greater range of COP movement and higher COP velocity in the anterior-posterior direction prior to movement initiation compared with TD. The DCD group also relied more on external support during both the downward and upward phases of the CPT and needed more trials to complete the task. Only two significant interaction effects involving Group and the within-subject factors emerged. Children with DCD swayed significantly more at specific phases of the task, especially when coming up and restoring balance, and did not adapt COP velocity as a function of reaching distance. Dynamic control of posture in children with DCD is impaired as they struggle to generate the effective APAs necessary to maintain dynamic stability which leads to greater reliance on external support and more corrective movements. The CPT provides a valuable assessment of posture and dynamic balance control during a complex prehension movement performed on one leg; the task highlights distinct movement patterns between children with and without DCD.

Short- and Long-Term Changes in Balance After Active Video Game Training in Children With and Without Developmental Coordination Disorder: A Randomized Controlled Trial.

Active video games (AVG) have been used as training tools and are known to ameliorate balance performance in children with Developmental Coordination Disorder (DCD). Our aim was to evaluate balance using clinical tests and by measuring body sway using a force plate with a mixed design of vision (eyes open/eyes closed), surface (rigid/soft), and support (stance/semitandem) before, and after, training and 4 months later (follow-up). Thirty-six DCD children and 40 typically developing children participated in the study, of which 50 children (26 DCD; 24 typically developing) were retested after 4 months. Balance improved on the clinical measures after the training, which was independent of type of AVG (Wii-Fit and Xbox Kinect) used, and this effect was still present after 4 months. The AVG training did not influence general sway behavior, but only sway in the eyes-open condition, corresponding with task demands of the training and indicating a training-specific effect. Overall, DCD children and typically developing children responded comparably to the AVG training, thereby maintaining the gap in performance between the two groups. The changes in postural sway are interpreted as a sign of more confidence and less freezing of the joints, enabling greater flexibility of movements and balance strategies as supported by the improved performance on balance tests in the DCD children. This is the first study that showed long-term effects of AVG training on balance performance. However, these follow-up results should be interpreted with caution given that 35% of the children were lost in follow-up.

Task-specificity and transfer of skills in school-aged children with and without developmental coordination disorder.

AIM: To compare the effects of two Active Video Game (AVG) protocols on transfer of learning in children with and without Developmental Coordination Disorder (DCD). METHODS: Fifty children, aged 6-10 years were randomly allocated to either group A or B. Children in group A participated in a set of Nintendo Wii ball games whereas group B played agility games (8 DCD and 17 typically developing children (TD) per group). Participants in each group practiced Wii games for 20 min twice a week for 10 weeks. All children also practiced ball and agility games in real-world settings, once per week. RESULTS: Both protocols yielded positive effects with the largest effect sizes shown on agility and balance items of the PERF-FIT and KTK tests. No interaction was found on learning real-world games and the virtual protocol, except for a Ping-Pong game. A significant interaction of time by protocol group indicated that the Ball group improved more on BOT-2-Upper-Limb Coordination than the Agility group. Importantly, children with DCD improved comparably with TD peers in virtual and real-world games. CONCLUSION: Independent of training protocol, both children with DCD and TD children performed better on trained and non-trained ball, balance and agility tasks after 10 weeks of training.

Improved attentional abilities after playing five weeks of active video games in children with and without developmental coordination disorder.

BACKGROUND: Besides motor coordination problems, attentional impairments are reported in children with developmental coordination disorder (DCD), but the connection or trainability is still unclear. AIM: To test changes on attentional abilities after playing active video games (AVG) in children with DCD and their peers (TD), to evaluate near transfer and the relationship between omissions in attentional and motor tests. METHODS: Seventy children (35 DCD; 35 TD), 7-12 years old, were assessed on three types of attention: distractibility (DIS); divided-attention (DA); sustained-attention (SA) and on the Wii Fit test pre- and post-training. RESULTS: A significant decrease of errors in attentional tasks was found after training, independent of group (TD/DCD) and console (Wii Fit/Xbox) with medium-strong effect sizes (DIS η2p =.42; DA η2p =.51; SA η2p =.41). The groups responded similarly to the training but the DCD children scored poorer on the DA. A positive transfer-effect to the non-trained Wii Fit test was found in accuracy (missed gates), while speed proved console-specific. A medium/strong relation was found between omissions in attentional tasks and the missed gates (Wii Fit test). CONCLUSION: More accurate responses on attentional tasks were found after AVG-training in both groups. A clear relationship between attentional abilities and motor performance was found.

Reference values for the muscle power sprint test in 6- to 12-year-old children.

PURPOSE: The aims of this study were (1) to develop centile reference values for anaerobic performance of Dutch children tested using the Muscle Power Sprint Test (MPST) and (2) to examine the test-retest reliability of the MPST. METHODS: Children who were developing typically (178 boys and 201 girls) and aged 6 to 12 years (mean = 8.9 years) were recruited. The MPST was administered to 379 children, and test-retest reliability was examined in 47 children. MPST scores were transformed into centile curves, which were created using generalized additive models for location, scale, and shape. RESULTS: Height-related reference curves were created for both genders. Excellent (intraclass correlation coefficient = 0.98) test-retest reliability was demonstrated. CONCLUSIONS: The reference values for the MPST of children who are developing typically and aged 6 to 12 years can serve as a clinical standard in pediatric physical therapy practice. The MPST is a reliable and practical method for determining anaerobic performance in children.

Do We Drop the Ball When We Measure Ball Skills Using Standardized Motor Performance Tests?

BACKGROUND: Ball skill performance changes over time during childhood and depends on the child's physical and psychological characteristics, environmental opportunities, and task constraints. The aim of this study was to examine whether different standardized ball skill-items measure similar constructs and whether results differentiate among age groups. Methods: A total of 250 children (6-10 years) were administered the Movement Assessment Battery for children second edition (MABC-2), the subtest upper-limb coordination of the Bruininks-Oseretsky Test of Motor Proficiency second edition (BOT-2), the tennis ball throw of the Fitness Test Battery (FTB), and the ball skills and overhead throw of the Performance and Fitness test (PERF-FIT). Results: Correlations among scores of BOT-2, FTB, and PERF-FIT ranged from fair to moderate, but correlations were low with the MABC-2. Principal component analysis retrieved three components: the first component contained catch, dribble, bounce, and throw items (MABC-2, BOT-2-SF, and PERF-FIT, respectively); the second contained throwing for distance (PERF-FIT and FTB); the third contained aiming (MABC-2). Most ball skill scores differed significantly between 6-7 and 7-8 years, but less between 8-9 years; the PERF-FIT discriminated best between age groups. Conclusion: Most ball skill items in motor tests belong to a comparable construct containing throw, dribble, bounce, and catch skills. However, aiming tasks belong to a separate category. Additionally, throwing for distance is a task that requires predominantly explosive power.

Active Video Games Performance and Heart Rate on the Wii or Kinect in Children with and without Developmental Coordination Disorder.

Our objective was to compare changes in game performance and intensity of heart rate (HR) between two types of active video game (AVG) in children with and without Developmental Coordination Disorder (DCD). Additionally, we assessed the level of improvement per game as well as the perceived exertion and enjoyment during training. Seventy-six children, 36 with DCD and 40 without (TD) were randomly assigned to a 5-week program of Wii-Fit or Xbox-Kinect training 2× a week. The steepness of the performance curves was not different between consoles, nor between groups. Playing Kinect games resulted in higher HR in both groups. Wii and Kinect seem to be comparable AVG consoles that can be used for children with and without DCD, with the Kinect reaching a higher intensity of training.

Effectiveness and feasibility of We12BFit!: improving physical fitness and lifestyle physical activity in children with developmental coordination disorder in a paediatric rehabilitation setting-a small sample field study.

OBJECTIVES: To examine the effectiveness and feasibility of We12BFit!, a family-focused intervention aimed at increasing physical fitness (PF) and motivation for physical activity (PA) in 7-year-old to 12-year-old children with developmental coordination disorder (DCD). DESIGN: A single-arm mixed methods small sample field study. SETTING: Rehabilitation centres and schools for special education in The Netherlands. PARTICIPANTS: Twenty children with DCD diagnosis. INTERVENTIONS: We12BFit! consists of We12BFit!-PF and We12BFit!-Lifestyle PA. During We12BFit!-PF, cardiorespiratory fitness (CRF), muscle strength and anaerobic power were trained in small groups (10 weeks 2*60 min/week). We12Bfit!-Lifestyle PA, which addresses motivation for PA in children and parents, was added in week 6 of We12BFit!-PF and ended 12 weeks after We12BFit!-PF. OUTCOME MEASURES: The 20-Metre Shuttle Run Test (20mSRT), Muscle Power Sprint Test and Hand Held Dynamometry were performed before and after We12BFit!-PF and after We12BFit!-Lifestyle PA (T0-T1-T2). Parents and coaches were interviewed and trainers participated in a focus group to assess motivation for PA, perceived effectiveness, and feasibility of the intervention. RESULTS: Attendance rates of participants were 88% (We12BFit!-PF) and 89% (We12BFit!-Lifestyle PA). From T0 to T1, significant improvements were found in VO2peak, number of runs on the 20mSRT and mean anaerobic power. From T1 to T2, improvements were maintained. No changes were found after We12BFit!-Lifestyle PA in time spent on moderate to vigorous activity and metabolic equivalent of task; parents observed their child improved in qualitative aspects of activities and participation. Feasibility of We12Bfit! was confirmed, although some adaptations were recommended. CONCLUSIONS: We12BFit! resulted in significant improvements and maintenance of CRF and anaerobic power in a small group of children with DCD and seemed to improve motivation for PA. The group aspect of We12BFit!-PF, the high intensity and positive motivational climate of We12BFit!-PF may have improved children's self-efficacy. We12BFit! seems feasible to improve PF and PA in children with DCD. TRIAL REGISTRATION NUMBER: NTR6334.

Field-Based Tests of Strength and Anaerobic Capacity Used in Children With Developmental Coordination Disorder: A Systematic Review.

OBJECTIVE: Children with developmental coordination disorder (DCD) are reported to have lower levels of strength and anaerobic capacity. The purpose of this study was to (1) identify field-based tests for strength and anaerobic capacity used in studies comparing children with DCD and children who were typically developing (TD), (2) examine the methodological quality of studies reporting psychometric properties and rate the psychometric properties of the examined test, and (3) summarize available evidence by combining the methodological quality of the studies and the quality of the psychometric properties of the test. METHODS: An electronic search was conducted in July 2019 in 4 electronic databases. For purpose 1, primary studies were included with no exclusion of study design in which children aged 4 to 18 years with DCD were compared with children who were TD on strength and/or anaerobic capacity measures. For purpose 2, primary studies were included with no exclusion of study design in which a psychometric property was investigated. The Consensus-Based Standards for Selection of Health Measurement Instruments (COSMIN) was used to evaluate the methodological quality of the 34 studies and rate the psychometric properties of the tests used. RESULTS: Hand-held dynamometer, bent knee push-up, vertical jump, standing long-jump, functional strength measurement, fitness test, and test battery can be recommended for TD, and the shuttle run item of the Bruininks-Oseretsky Test of Motor Proficiency-Second Edition and 10 m × 5 m sprints (straight and slalom) can be recommended for DCD. CONCLUSION: Information regarding psychometric properties of field-based tests for strength and anaerobic capacity in children with DCD is lacking. IMPACT: Information about the psychometric properties of field-based tests for strength and anaerobic capacity in children with DCD is lacking. More information is available on TD children, but it is also not complete; information regarding validity and responsiveness, especially, is missing. When using measures in children with DCD, it is important to keep in mind this lack of evidence for the validity and reliability of the outcomes for this target group.

Construct validity of the PERF-FIT, a test of motor skill-related fitness for children in low resource areas.

BACKGROUND: Given the relationship between physical fitness and motor performance a test battery was developed that measures both components combined. AIM: Following the development of the Performance and Fitness (PERF-FIT) battery, this study investigated the construct validity with the ultimate aim of identifying attributes that discriminate between different levels of motor abilities and anaerobic or musculoskeletal fitness. METHODS: In this cross-sectional study, 34 children with developmental coordination disorder (DCD) and 34 matched typically developing children participated (7-10 years). The PERF-FIT was used to examine known group validity. The PERF-FIT items were also compared to test items of well-known standardized tests to examine concurrent validity. RESULTS: Concurrent validity was found to be of the expected low to moderate magnitude. Children with DCD were consistently found to have lower levels of motor skill-related fitness compared to typically developing children. CONCLUSION AND IMPLICATIONS: The PERF-FIT seems to be a valid test to measure movement skills, musculoskeletal fitness and agility in children between the ages of 7 and 10 years in low resourced communities. The test seems to discriminate between gross motor skills, and agility and power in children with and without DCD.

Variable training does not lead to better motor learning compared to repetitive training in children with and without DCD when exposed to active video games.

BACKGROUND: Little is known about the influence of practice schedules on motor learning and skills transfer in children with and without developmental coordination disorder (DCD). Understanding how practice schedules affect motor learning is necessary for motor skills development and rehabilitation. AIMS: The study investigated whether active video games (exergames) training delivered under variable practice led to better learning and transfer than repetitive practice. METHODS AND PROCEDURES: 111 children aged 6-10 years (M=8.0, SD=1.0) with no active exergaming experience were randomized to receive exergames training delivered under variable (Variable Game Group (VGG), n=56) or repetitive practice schedule (Repetitive Game Group (RGG), n=55). Half the participants were identified as DCD using the DSM-5 criteria, while the rest were typically developing (TD), age-matched children. Both groups participated in two 20min sessions per week for 5 weeks. OUTCOMES AND RESULTS: Both participant groups (TD and DCD) improved equally well on game performance. There was no significant difference in positive transfer to balance tasks between practice schedules (Repetitive and Variable) and participant groups (TD and DCD). CONCLUSIONS AND IMPLICATIONS: Children with and without DCD learn balance skills quite well when exposed to exergames. Gains in learning and transfer are similar regardless of the form of practice schedule employed. WHAT THIS PAPER ADDS: This is the first paper to compare the effect of practice schedules on learning in children with DCD and those with typical development. No differences in motor learning were found between repetitive and variable practice schedules. When children with and without DCD spend the same amount of time on exergames, they do not show any differences in acquisition of motor skills. Transfer of motor skills is similar in children with and without DCD regardless of differences in practice schedules.

Short-term motor learning of dynamic balance control in children with probable Developmental Coordination Disorder.

PURPOSE: To explore the differences in learning a dynamic balance task between children with and without probable Developmental Coordination Disorder (p-DCD) from different cultural backgrounds. PARTICIPANTS: Twenty-eight Dutch children with DCD (p-DCD-NL), a similar group of 17 South African children (p-DCD-SA) and 21 Dutch typically developing children (TD-NL) participated in the study. METHODS: All children performed the Wii Fit protocol. The slope of the learning curve was used to estimate motor learning for each group. The protocol was repeated after six weeks. Level of motor skill was assessed with the Movement ABC-2. RESULTS: No significant difference in motor learning rate was found between p-DCD-NL and p-DCD-SA, but the learning rate of children with p-DCD was slower than the learning rate of TD children. Speed-accuracy trade off, as a way to improve performance by slowing down in the beginning was only seen in the TD children, indicating that TD children and p-DCD children used different strategies. Retention of the level of learned control of the game after six weeks was found in all three groups after six weeks. The learning slope was associated with the level of balance skill for all children. This study provides evidence that children with p-DCD have limitations in motor learning on a complex balance task. In addition, the data do not support the contention that learning in DCD differs depending on cultural background.

The impact of Wii Fit intervention on dynamic balance control in children with probable Developmental Coordination Disorder and balance problems.

The aim of this study was to examine differences in the performance of children with probable Developmental Coordination Disorder (p-DCD) and balance problems (BP) and typical developing children (TD) on a Wii Fit task and to measure the effect on balance skills after a Wii Fit intervention. Twenty-eight children with BP and 20 TD-children participated in the study. Motor performance was assessed with the Movement Assessment Battery for Children (MABC2), three subtests of the Bruininks Oseretsky Test (BOT2): Bilateral Coordination, Balance and Running Speed & Agility, and a Wii Fit ski slalom test. The TD children and half of the children in the BP group were tested before and after a 6weeks non-intervention period. All children with BP received 6weeks of Wii Fit intervention (with games other than the ski game) and were tested before and afterwards. Children with BP were less proficient than TD children in playing the Wii Fit ski slalom game. Training with the Wii Fit improved their motor performance. The improvement was significantly larger after intervention than after a period of non-intervention. Therefore the change cannot solely be attributed to spontaneous development or test-retest effect. Nearly all children enjoyed participation during the 6weeks of intervention. Our study shows that Wii Fit intervention is effective and is potentially a method to support treatment of (dynamic) balance control problems in children.

Effect of Wii-intervention on balance of children with poor motor performance.

The purpose of this study was to investigate the effects of training with the Wii-balance board on balance and balance-related skills of children with poor motor performance. Twenty-nine children (23 boys, 6 girls; aged 7-12 years) participated in this study and were randomly assigned to an experimental and control group. All children scored below the 16th percentile on a standardized test of motor ability and balance skills (Movement Assessment Battery for children (M-ABC-2)). Before and after a six-week Wii-intervention (M=8h, 22 min, SD=53 min), the balance skills of the experimental group and control group were measured with the M-ABC-2 and the Bruininks-Oseretsky test of motor proficiency (BOT-2). Both groups improved on all tests. The M-ABC-2 and the BOT-2 total balance-scores of the experimental group improved significantly from pre to post intervention, whereas those of the control group showed no significant progress. This resulted in significant interaction-effects, favoring the experimental children. No transfer-effects of the intervention on balance-related skills were demonstrated. Our findings showed that the Wii-balance board is an effective intervention for children with poor balance control. Further development and investigation of the intervention could be directed toward the implementation of the newly acquired balance-skills in daily life.