Changes in kinetics and kinematics of handwriting during a prolonged writing task in children with and without dysgraphia

Participatory design and needs assessment for a pressure-sensitive pen and mobile application (SensoGrip) for children with handwriting problems

PURPOSE

Problems with handwriting are a common referral to occupational therapy in children and are often associated with inadequate pen grip and tip pressure. Technologies providing immediate feedback on applied forces are currently not available. Therefore, the aim was to identify user's perspectives on the optimal functionality of a pressure-sensitive pen with an integrated feedback system.

METHODS

To ensure that the product meets the requirements of the users, user needs of paediatric occupational therapists, elementary or special education teachers and children were collected in two focus groups and a children's workshops before starting the technical development process. Focus group transcripts were analyzed and rephrased as user stories to identify user-centred requirements. In a second step, user stories were merged and ranked regarding importance and feasibility.

RESULTS

120 user story requirements were generated from the focus groups and children's workshops, indicating requirements regarding design and functionality for the pen and mobile application. Visual feedback, appropriate size and weight, customizability, ease of settings and usability of the pen were pivotal.

CONCLUSIONS

This study comprehensively researched the requirements for a device that may facilitate children in adjusting their handwriting pressure and can guide further research and evaluation.

The Modularity of Dysgraphia

Research regarding dysgraphia, an impairment in writing, is attaining more attention in recent times. The existing studies on dysgraphia draw insights from cognitive, behavioural, neurological, and genetic fields of knowledge. However, these multiple studies on dysgraphia fail to illustrate how these cognitive, behavioural, neurological, and genetic systems interact and intersect in dysgraphia. Therefore, the studies could not offer a comprehensive understanding of dysgraphia. In order to fill this gap, the review attempts to study dysgraphia using the notion of modularity by accommodating insights from cognitive, behavioural, neurological, and genetic aspects of dysgraphia. Such a profound understanding could facilitate an early diagnosis and holistic intervention towards dysgraphia.

Specific Learning Disorders (SLD) and Behavior Impairment: Comorbidity or Specific Profile?

INTRODUCTION

Specific Learning Disorder (SLD) is a neurodevelopmental disorder characterized by difficulties in perceiving and processing verbal and non-verbal information. It is usually accompanied by impaired academic skills leading to school dropout and emotional disturbances, resulting in significant distress and behavioral problems.

METHODS

A cognitive, academic, and emotional-behavioral assessment was performed at T0 and T1 in children and adolescents with SLD. Participants received psychotherapy and speech therapy treatment from T0 to T1.

RESULTS

In SLD, the most compromised cognitive functions were working memory and writing skills. An impact on academic abilities was found. Children and adolescents with SLD experience greater anxiety and depression levels compared to their control peers.

CONCLUSIONS

SLD may adversely influence psychological well-being. To counteract such a consequence, more specific cognitive and academic skill-oriented strategies should be taken into consideration.

Translation, Cross-Cultural Adaptation, and Psychometric Properties of Writing Readiness Inventory Tool in Context (WRITIC)

This article describes the translation and cultural adaptation process of the WRITIC (Writing Readiness Inventory Tool in Context) into European Portuguese. We examined the content and convergent validity, test-retest, and interrater reliability on the norm-referenced subdomain of the Portuguese (PT) WRITIC Task Performance (TP). To establish content validity, we consulted six experts in handwriting. Internal consistency was found with 70 children, test-retest reliability with 65, inter-rater reliability with 69, and convergent validity with 87. All participants were typically developing kindergarten children. Convergent validity was examined with the Beery–Buktenica Developmental Test of Visual-Motor Integration (Beery™VMI-6) and the Nine Hole Peg-Test (9-HPT). On content validity, we found an agreement of 93%, a good internal consistency with Cronbach’s alpha of 0.72, and an excellent test-retest and inter-rater reliability with ICCs of 0.88 and 0.93. Correlations with Beery™VMI-6 and 9-HPT were moderate (r from 0.39 to 0.65). Translation and cross-cultural adaptation of WRITIC into European Portuguese was successful. WRITIC-PT-TP is stable over time and between raters; it has excellent internal consistency and moderate correlations with Beery™VMI-6 and 9-HPT. This analysis of the European Portuguese version of WRITIC gives us the confidence to start the implementation process of WRITIC-PT in Portugal.

Relationship between Product and Process Characteristics of Handwriting Skills of Children in the Second Grade of Elementary School

The purpose of this study was to analyze the relationship between the quality and speed of handwriting and the process characteristics of the handwriting of children in the second grade of elementary school considered as a function of age and gender. A sample of 57 children (mean age 7.25 years, SD 0.43) participated in the study. The Concise Assessment Method for Children’s Handwriting (BHK) was used to assess the quality and speed of handwriting. The characteristics of the process of handwriting were assessed using MovAlyzeR® software. The handwriting of boys showed a significantly greater number of strokes and slanted more to the right than the handwriting of girls. Handwriting quality and speed significantly correlated with several process characteristics: the number of strokes, reaction time, duration, relative pen-down duration, average pen pressure, vertical size, horizontal size, road length, and average absolute velocity. This research contributes to the construction of normative values in the process characteristics of the handwriting of elementary school children and provides a promising step towards the early identification of difficulties that can lead to dysgraphia, thus preventing later difficulties in handwriting.

Assessment of children's writing features: A pilot method study of pen-grip kinetics and writing surface pressure

The writing process is a complex task involving dexterous manipulation of the writing instrument by the hand digits and biomechanical ergonomic factors that contribute to handwriting efficiency and productivity. We describe a pilot study using an instrumented writing apparatus - a sensor (pen) and a digitized writing surface (tablet) - to measure the pen-grip kinetics (digit forces) and the pen pressure applied to the tablet during a writing task. Eight elementary school students with no handwriting difficulties copied a short story. The mean digit forces on the pen were compared with the mean pen pressure on the tablet at five interval points. Results revealed that the digit forces on the pen were significantly stronger than the pen pressure on the tablet. Results also showed significantly less digit-force variability throughout the writing task than the pen-pressure variability on the writing surface, which significantly lessened toward the end of the writing task. Information on these properties can broaden understanding of the elements that influence nonproficient handwriting in children with dysgraphia. Results also indicate the possible efficacy of a therapeutic tool for handwriting assessment and intervention using objective measurements during writing, warranting future studies with children with and without dysgraphia.

A Scoping Review of Grasp and Handwriting Performance in School-Age Children

OBJECTIVE

Handwriting is a critical functional skill that impacts academic participation and progress. Occupational therapists address components of grasp in their handwriting intervention as it is commonly assumed that grasp affects legibility, fluency, and endurance, yet research studies examining this relationship are limited.

METHOD

We used scoping review methodology to map existing research on grasp and handwriting performance in school-age children and to identify gaps in the literature.

RESULTS

Thirteen articles met search criteria and were categorized by grasp patterns and handwriting performance, and grasp force and handwriting performance. Findings suggest an inefficient grasp can lead to decreased handwriting legibility and fatigue. The current literature is inconclusive and several gaps were identified.

CONCLUSION

Additional studies should address research gaps through inclusion of children with special needs and interventions including lengthier handwriting tasks representative of a typical school day.

Upper Limb Kinematics of Handwriting among Children with and without Developmental Coordination Disorder

Background: Children with developmental coordination disorder (DCD) often experience difficulties with handwriting legibility and speed. This study investigates the relationship between handwriting and upper limb kinematics to characterize movement patterns of children with DCD and typically developing (TD) children. Methods: 30 children with and without DCD matched for age, gender, and parent education were compared across handwriting abilities using a standardized handwriting assessment of both copied and dictated tasks (A-A Handwriting). The 3D motion capture system (Qualysis) was used to analyze upper limb kinematics and characterize movement patterns during handwriting and contrasted with written output. Results: Children with DCD wrote fewer legible letters in both copying and dictation. Children with DCD also showed poor automatization of key writing concepts. Atypical wrist postures were associated with reduced legibility for children with DCD (F (1,27) 4.71, p = 0.04, p-η2 = 0.15); whereas for TD children, better legibility was associated with greater variations in movement speed, particularly of the wrist (rho = −0.578, p < 0.05). Conclusion: Results reflect different movement parameters influencing handwriting in children with DCD. An improved understanding of the movement characteristics during handwriting of these children may assist intervention design.

Handwriting and Motor-Related Daily Performance among Adolescents with Dysgraphia and Their Impact on Physical Health-Related Quality of Life

Knowledge is limited about dysgraphia in adolescence and its association with daily motor-related daily performance and health-related quality of life (HRQOL). This study aimed to (1) compare and (2) examine correlations between handwriting measures, motor-related daily performance, and HRQOL of adolescents with and without dysgraphia and (3) examine the contribution of motor-related daily performance and handwriting measures to predict their physical HRQOL. There were eighty adolescents (13-18 yr): half with dysgraphia and half matched controls without dysgraphia per the Handwriting Proficiency Screening Questionnaire and Handwriting Legibility Scale participated. They copied a paragraph script onto a paper attached to the Computerized Penmanship Evaluation Tool digitizer and completed the World Health Organization Quality of Life Questionnaire-brief version and the Adult Developmental Coordination Disorder Checklist (ADC). We found significant between-group differences in motor-related daily performance, handwriting measures, and HRQOL and significant correlations between HRQOL and handwriting process measures and motor-coordination ability. Handwriting measures predicted 25%, and the ADC A and C subscales 45.6%, of the research group's physical QOL domain score variability. Notably, the control group's current perceptions of their motor-coordination performance (ADC-C) predicted 36.5% of the variance in physical QOL. Dysgraphia's negative effects during childhood and adolescence may reduce adolescents' HRQOL now and into adulthood.

Pen-grip kinetics in children with and without handwriting difficulties

Introduction

Handwriting difficulty (HD) is a widely discussed issue. Previous researchers have revealed many valuable kinematics related to the handwriting performance. However, a clear understanding of the kinetics of handwriting performance in children with HD is still lacking. Therefore, this study investigated the writing performance of children with HD via a force acquisition pen (FAP), which detects the force applied from the digits and pen tip.

Methods

Data from 64 school-age children were divided into control (36 children without HD; mean age: 7.97 years) and HD (28 children with HD; mean age: 8.67 years) groups. The participants were asked to perform a tracing task using the FAP at their usual writing pace.

Results

Compared with the control group, the HD group had significantly less pen-tip force, an average amount of force (in-air) from all three digits, higher force variations (whole task) in the index finger, less force fluctuations with the index and middle fingers and a smaller force ratio.

Conclusion

The findings of this study suggest that an understanding of the handwriting kinetics and the role of digits in handwriting may be crucial for further planning strategies for handwriting training for children with HD.

Comparison of CNN-Learned vs. Handcrafted Features for Detection of Parkinson's Disease Dysgraphia in a Multilingual Dataset

Parkinson's disease dysgraphia (PDYS), one of the earliest signs of Parkinson's disease (PD), has been researched as a promising biomarker of PD and as the target of a noninvasive and inexpensive approach to monitoring the progress of the disease. However, although several approaches to supportive PDYS diagnosis have been proposed (mainly based on handcrafted features (HF) extracted from online handwriting or the utilization of deep neural networks), it remains unclear which approach provides the highest discrimination power and how these approaches can be transferred between different datasets and languages. This study aims to compare classification performance based on two types of features: features automatically extracted by a pretrained convolutional neural network (CNN) and HF designed by human experts. Both approaches are evaluated on a multilingual dataset collected from 143 PD patients and 151 healthy controls in the Czech Republic, United States, Colombia, and Hungary. The subjects performed the spiral drawing task (SDT; a language-independent task) and the sentence writing task (SWT; a language-dependent task). Models based on logistic regression and gradient boosting were trained in several scenarios, specifically single language (SL), leave one language out (LOLO), and all languages combined (ALC). We found that the HF slightly outperformed the CNN-extracted features in all considered evaluation scenarios for the SWT. In detail, the following balanced accuracy (BACC) scores were achieved: SL—0.65 (HF), 0.58 (CNN); LOLO—0.65 (HF), 0.57 (CNN); and ALC—0.69 (HF), 0.66 (CNN). However, in the case of the SDT, features extracted by a CNN provided competitive results: SL—0.66 (HF), 0.62 (CNN); LOLO—0.56 (HF), 0.54 (CNN); and ALC—0.60 (HF), 0.60 (CNN). In summary, regarding the SWT, the HF outperformed the CNN-extracted features over 6% (mean BACC of 0.66 for HF, and 0.60 for CNN). In the case of the SDT, both feature sets provided almost identical classification performance (mean BACC of 0.60 for HF, and 0.58 for CNN).

Kinematic analysis of handwriting movements and pencil grip patterns in children with low vision

PURPOSE

Handwriting skills are important for the academic life of children and the lack of visual-motor performance leads to writing problems in children with low vision. This study aims to reveal handwriting kinematics and pencil grip features in children with low vision by means of a novel method.

MATERIALS AND METHODS

18 children with low vision (mean age: 9.83 ± 1.54 years) and 18 children with typical development (mean age: 9.83 ± 1.62 years) were included in the study. Children performed a sentence writing task on a digitizer tablet. During the task, the writing hand of children was photographed to analyze pencil grip patterns.

RESULTS

Children with low vision performed greater stroke size except for the vertical size, slower writing speed, more dysfluent movements, and less pen pressure than children with typical development. However, participants preferred mature pencil grip patterns and had high grip scores independent from the diagnosis.

CONCLUSIONS

The findings indicate that children with low vision have difficulties in handwriting in terms of spatial and temporal features. These results would be important for interventions to develop specific programs on writing skills to support their educational life.

Differences in Levodopa Response for Progressive and Non-Progressive Micrographia in Parkinson's Disease

Background: Micrographia, one element of the dysgraphia of Parkinson's disease (PD), may be classified according to the presence or absence of a decremental pattern. The decremental form, progressive micrographia, is an expression of the sequence effect seen generally in bradykinesia. Its responsiveness to levodopa has not been evaluated kinematically. Objectives: Aim of this study is to investigate the difference in levodopa response for progressive and non-progressive micrographia. Methods: Twenty-four PD patients and 24 age-matched repeatedly wrote the letter e on a computerized digital tablet. PD patients performed the task two times, in a defined off state and again after levodopa. Scripts were classified as progressive micrographia (PD_PM) or non-progressive micrographia (PD_NPM) depending on whether a 10% decrement was seen between the first and final characters of a line of lettering. Results: While levodopa produced a similar response on the MDS-UPDRS motor scale for the two groups, the effect on the two types of micrographia was different. While writing speed improved significantly in both groups after levodopa, the responses were over twofold greater for PD_NPM. Moreover, the decremental features of PD_PM-in size, speed, and pen-pressure-were largely unaltered by a levodopa dose. Conclusions: Progressive micrographia is less responsive to levodopa. Our findings agree with research showing that the sequence effect of bradykinesia is relatively resistant to medication. Yet we did not find a weaker overall levodopa motor benefit. Caution is needed in the interpretation of such micrographia measurements for estimating drug responses.

Sensorised Low-Cost Pencils for Developing Countries: A Quantitative Analysis of Handwriting Learning Progress in Children with/without Disabilities from a Sustainable Perspective

Learning to write is a demanding endeavour that requires a combination of linguistic, motor and cognitive skills. Some children suffer from delay or inability to acquire those skills, which often hampers their performance at school and brings about serious consequences for self-esteem, personal expectations and social relationships. The situation worsens in developing countries, due to the lack of resources and specialised personnel. With this background, this paper describes an experiment with a newly-developed sensorised pencil with triangular prism shape, which is shown to yield substantial improvements in children with/without special education needs. A team of experts in the areas of speech therapy, occupational therapy, educational psychology, physiotherapy and pedagogy have expressed very positive opinions about the sensorised pencil and the accompanying software for the acquisition and analysis of quantitative data about handwriting. Furthermore, the device stands out for its low cost in comparison with similar developments, which is a key factor to aid children from low-income families. This fact is explained with a success story of manufacturing and delivering sensorised pencils in the Ecuadorian province of Azuay, framed in a multi-layer sustainable development perspective based on collaboration of several institutions and individuals.

Can jaw position affect the fine motor activity of the hand during writing?

BACKGROUND

Jaw and neck systems have been shown to be functionally related and changes in either system can modulate gross motor functions, such as posture control. It remains to be seen if any change in jaw position can affect fine motor skills. The objective of this study was to determine the effect of resting, open and clenched jaw positions on various handwriting parameters while standing on firm and unstable surfaces.

METHODS

Handwriting samples were collected from 36 healthy male participants (age, 15-35 years) using a digitizer tablet (WACOM Intuos 4) with noninking pen in the resting, open and clenched jaw positions while standing on firm and unstable surfaces. The measured handwriting parameters included duration, vertical size, horizontal size, absolute size, average absolute velocity, and absolute jerk. Recordings and analyses were performed using NeuroScript MovAlyzeR software.

RESULTS

All handwriting parameters varied among the resting, open, and clenched jaw positions on both the firm and unstable surfaces. However, based on statistical analyses, there were no significant differences in the handwriting parameters among three jaw positions on both surfaces (p > .05).

CONCLUSION

This study revealed that all handwriting parameters varied among the resting, open, and clenched jaw positions on both the firm and unstable surfaces, showing that change in the jaw motor system may potentially affect the fine motor skills. However, on statistical analysis, there was no significant effect of 3 studied jaw positions on fine motor skills as seen on gross motor skills among healthy individuals.

Disorder of written expression and dysgraphia: definition, diagnosis, and management

Writing is a complex task that is vital to learning and is usually acquired in the early years of life. 'Dysgraphia' and 'specific learning disorder in written expression' are terms used to describe those individuals who, despite exposure to adequate instruction, demonstrate writing ability discordant with their cognitive level and age. Dysgraphia can present with different symptoms at different ages. Different theories have been proposed regarding the mechanisms of dysgraphia. Dysgraphia is poorly understood and is often undiagnosed. It has a high rate of co-morbidity with other learning and psychiatric disorders. The diagnosis and treatment of dysgraphia and specific learning disorders typically centers around the educational system; however, the pediatrician can play an important role in surveillance and evaluation of co-morbidity as well as provision of guidance and support.

Developmental coordination disorder and dysgraphia: signs and symptoms, diagnosis, and rehabilitation

Developmental coordination disorder (DCD) is a common and well-recognized neurodevelopmental disorder affecting approximately 5 in every 100 individuals worldwide. It has long been included in standard national and international classifications of disorders (especially the Diagnostic and Statistical Manual of Mental Disorders). Children and adults with DCD may come to medical or paramedical attention because of poor motor skills, poor motor coordination, and/or impaired procedural learning affecting activities of daily living. Studies show DCD persistence of 30-70% in adulthood for individuals who were diagnosed with DCD as children, with direct consequences in the academic realm and even beyond. In particular, individuals with DCD are at increased risk of impaired handwriting skills. Medium-term and long-term prognosis depends on the timing of the diagnosis, (possible) comorbid disorders (and their diagnosis), the variability of signs and symptoms (number and intensity), and the nature and frequency of the interventions individuals receive. We therefore chose to investigate the signs and symptoms, diagnosis, and rehabilitation of both DCD and developmental dysgraphia, which continues to receive far too little attention in its own right from researchers and clinicians.

A Kinematic Study of Progressive Micrographia in Parkinson's Disease

Progressive micrographia is decrement in character size during writing and is commonly associated with Parkinson's disease (PD). This study has investigated the kinematic features of progressive micrographia during a repetitive writing task. Twenty-four PD patients with duration since diagnosis of <10 years and 24 age-matched controls wrote the letter “e” repeatedly. PD patients were studied in defined off states, with scoring of motor function on the Unified Parkinson's Disease Rating Scale Part III. A digital tablet captured x-y coordinates and ink-pen pressure. Customized software recorded the data and offline analysis derived the kinematic features of pen-tip movement. The average size of the first and the last five letters were compared, with progressive micrographia defined as >10% decrement in letter stroke length. The relationships between dimensional and kinematic features for the control subjects and for PD patients with and without progressive micrographia were studied. Differences between the initial and last letter repetitions within each group were assessed by Wilcoxon signed-rank test, and the Kruskal-Wallis test was applied to compare the three groups. There are five main conclusions from our findings: (i) 66% of PD patients who participated in this study exhibited progressive micrographia; (ii) handwriting kinematic features for all PD patients was significantly lower than controls (p < 0.05); (iii) patients with progressive micrographia lose the normal augmentation of writing speed and acceleration in the x axis with left-to-right writing and show decrement of pen-tip pressure (p = 0.034); (iv) kinematic and pen-tip pressure profiles suggest that progressive micrographia in PD reflects poorly sustained net force; and (v) although progressive micrographia resembles the sequence effect of general bradykinesia, we did not find a significant correlation with overall motor disability, nor with the aggregate UPDRS-III bradykinesia scores for the dominant arm.

The effect of task complexity on handwriting kinetics

BACKGROUND.

Knowledge regarding the relationship between writing kinetics and the difference among writing tasks is limited.

PURPOSE.

This study examined the differences in handwriting performance when doing tasks with different levels of challenge from both temporal and kinetic perspectives among children in four different age groups.

METHOD.

The cross-sectional design introduced a force-acquisition pen to detect differences of pen grip and writing kinetics among 170 school-age children doing writing tasks at different difficulty levels. Data were obtained on the force information of the digits and pen tip and the kinetic parameters to examine the coordination-and-control mechanism between the digits and pen. Statistical analyzes were carried out to indicate the differences in writing performance among groups and tasks.

FINDINGS.

Statistical differences in the pen-grip forces, force fluctuation, and force ratio between grip and pen-tip forces were found when performing different writing tasks and among different age groups.

IMPLICATIONS.

The study provides an alternative method to explore how writing performance among school-age children can vary according to the difficulty of the writing tasks.

Inter-relationships between objective handwriting features and executive control among children with developmental dysgraphia

Objective

To describe handwriting and executive control features and their inter-relationships among children with developmental dysgraphia, in comparison to controls.

Method

Participants included 64 children, aged 10–12 years, 32 with dysgraphia based on the Handwriting Proficiency Screening Questionnaire (HPSQ) and 32 matched controls. Children copied a paragraph onto paper affixed to a digitizer that supplied handwriting process objective measures (Computerized Penmanship Evaluation Tool (ComPET). Their written product was evaluated by the Hebrew Handwriting Evaluation (HHE). Parents completed the Behavior Rating Inventory of Executive Function (BRIEF) questionnaire about their child's executive control abilities.

Results

Significant group differences were found for handwriting performance measures (HHE and ComPET) and executive control domains (BRIEF). Based on one discriminate function, including handwriting performance and executive control measures, 98.4% of the participants were correctly classified into groups. Significant correlations were found in each group between working memory and legibility as well as for other executive domains and handwriting measures. Furthermore, twenty percent of the variability of the mean pressure applied towards the writing surface among children with was explained by their 'emotional control' (BRIEF).

Conclusion

The results strongly suggest consideration of executive control domains to obtain better insight into handwriting impairment characteristics among children with dysgraphia to improve their identification, evaluation and the intervention process.

Children's first handwriting productions show a rhythmic structure

Although much research has been concerned with the development of kinematic aspects of handwriting, little is known about the development along with age of two principles that govern its rhythmic organization: Homothety and Isochrony. Homothety states that the ratio between the durations of the single motor events composing a motor act remains invariant and independent from the total duration of the movement. Isochrony refers to the proportional relationship between the speed of movement execution and the length of its trajectory. The current study shows that children comply with both principles since their first grade of primary school. The precocious adherence to these principles suggests that an internal representation of the rhythm of handwriting is available before the age in which handwriting is performed automatically. Overall, these findings suggest that despite being a cultural acquisition, handwriting appears to be shaped by more general constraints on the timing planning of the movements.

Psychological and Physiological Processes in Figure-Tracing Abilities Measured Using a Tablet Computer: A Study with 7 and 9 Years Old Children

The present study investigated the use of a tablet computer to assess figure-tracing skills and their relationships with psychological (visual-perceptual processes, cognitive processes, handwriting skills) and physiological (body mass index, isometric strength of arms) parameters with school-children of second (7-8-year-olds) and fourth (9-10-year-olds) grades. We were also interested in gender differences. The task required tracing of geometric figures on a template, shown on a tablet screen in light gray, for the segments that make up the target figure, one at a time. This figure-tracing tablet test allows acquisition and automated analysis of four parameters: number of strokes (pen lift) for each segment; oscillations of lines drawn with respect to reference lines; pressure of pen on tablet; and average speed of tracing. The results show a trade-off between speed and quality for the tablet parameters, with higher speed associated with more oscillations with respect to the reference lines, and lower number of strokes for each segment, in both male and female children. The involvement of visual-motor integration on the ability to reduce the oscillations in this tablet test was only seen for the male children, while both the male and female children showed a relationship between oscillations and more general/abstract visual-spatial processes. These data confirm the role of visual-motor processes in this figure-tracing tablet test only for male children, while more general visual-spatial processes influence the performance in the tablet test for both sexes. We conclude that the test proposed is useful to screen for grapho-motor difficulties.

Programming generality into a performance feedback writing intervention: A randomized controlled trial

Substantial numbers of students in the United States are performing below grade-level expectations in core academic areas, and these deficits are most pronounced in the area of writing. Although performance feedback procedures have been shown to produce promising short-term improvements in elementary-aged students' writing skills, evidence of maintenance and generalization of these intervention effects is limited. The purpose of this study was to examine the immediate, generalized, and sustained effects of incorporating multiple exemplar training into the performance feedback procedures of a writing intervention using a randomized controlled trial (RCT). Results indicated that although the addition of multiple exemplar training did not improve students' writing performance on measures of stimulus and response generalization, it did result in greater maintenance of intervention effects in comparison to students who received performance feedback without generality programming and students who engaged in weekly writing practice alone.

Fluency and Accuracy in Alphabet Writing by Keyboarding: A Cross-Sectional Study in Spanish-Speaking Children With and Without Learning Disabilities

The aim of this study was to analyze whether children with and without difficulties in handwriting, spelling, or both differed in alphabet writing when using a keyboard. The total sample consisted of 1,333 children from Grades 1 through 3. Scores on the spelling and handwriting factors from the Early Grade Writing Assessment (Jiménez, in press) were used to assign the participants to one of four groups with different ability patterns: poor handwriters, poor spellers, a mixed group, and typically achieving students. Groups were equalized by a matching strategy, resulting in a final sample of 352 children. A MANOVA was executed to analyze effects of group and grade on orthographic motor integration (fluency of alphabet writing) and the number of omissions when writing the alphabet (accuracy of alphabet writing) by keyboard writing mode. The results indicated that poor handwriters did not differ from typically achieving children in both variables, whereas the poor spellers did perform below the typical achievers and the poor handwriters. The difficulties of poor handwriters seem to be alleviated by the use of the keyboard; however, children with spelling difficulties might need extra instruction to become fluent keyboard writers.

Digital Handwriting with a Finger or a Stylus: A Biomechanical Comparison

In this paper, we present a study concerning the human hand during digital handwriting on a tablet. Two different cases are considered: writing with the finger, and writing with the stylus. We chose an approach based on the biomechanics of the human hand to compare the two different input methods. Performance is evaluated using metrics originally introduced and developed in robotics, such as the manipulability indexes. Analytical results assess that writing with the finger is more suitable for performing large, but not very accurate motions, while writing with the stylus leads to a higher precision and more isotropic motion performance. We then carried out two experiments of digital handwriting to support the approach and contextualize the results.

Handwriting Proficiency Screening Questionnaire for Children (HPSQ–C): Development, Reliability, and Validity

OBJECTIVE. To adapt the Handwriting Proficiency Screening Questionnaire (HPSQ), previously designated for adults, into a children’s self-report version (the HPSQ for Children, or HPSQ–C) and to examine its reliability and validity.

METHOD. Participants included 230 children ages 7–14 yr from regular schools in Israel. The questionnaire’s content validity, internal consistency, and concurrent and construct validity were assessed.

RESULTS. The tool demonstrated good internal consistency (α = .77). We found a significant moderate correlation between final HPSQ–C scores and the HPSQ, r = .51, p &lt; .001, establishing the HPSQ–C’s concurrent validity. Construct validity was also confirmed. Results demonstrated that the HPSQ–C significantly distinguished between children with and without handwriting deficiencies on the basis of measures of handwriting product (Hebrew Handwriting Evaluation) and handwriting process (Computerized Penmanship Evaluation Tool).

CONCLUSION. The HPSQ–C is suitable for identification of handwriting deficiency among school-aged children and is appropriate for varied academic and clinical uses.

Characterization of fine motor development: dynamic analysis of children's drawing movements

In this study, we investigated children's fine motor development by analyzing drawing trajectories, kinematics and kinetics. Straight lines drawing task and circles drawing task were performed by using a force sensitive tablet. Forty right-handed and Chinese mother-tongue students aged 6-12, attending classes from grade 1 to 5, were engaged in the experiment. Three spatial parameters, namely cumulative trace length, vector length of straight line and vertical diameter of circle were determined. Drawing duration, mean drawing velocity, and number of peaks in stroke velocity profile (NPV) were derived as kinematic parameters. Besides mean normal force, two kinetic indices were proposed: normalized force angle regulation (NFR) and variation of fine motor control (VFC) for circles drawing task. The maturation and automation of fine motor ability were reflected by increased drawing velocity, reduced drawing duration, NPV and NFR, with decreased VFC in circles drawing task. Grade and task main effects as well as significant correlations between age and parameters suggest that factors such as schooling, age and task should be considered in the assessment of fine motor skills. Compared with kinematic parameters, findings of NFR and VFC revealed that kinetics is another important perspective in the analysis of fine motor movement.

Underlying mechanisms of writing difficulties among children with neurofibromatosis type 1

Writing is a complex activity in which lower-level perceptual-motor processes and higher-level cognitive processes continuously interact. Preliminary evidence suggests that writing difficulties are common to children with Neurofibromatosis type 1 (NF1). The aim of this study was to compare the performance of children with and without NF1 in lower (visual perception, motor coordination and visual-motor integration) and higher processes (verbal and performance intelligence, visual spatial organization and visual memory) required for intact writing; and to identify the components that predict the written product's spatial arrangement and content among children with NF1. Thirty children with NF1 (ages 8-16) and 30 typically developing children matched by gender and age were tested, using standardized assessments. Children with NF1 had a significantly inferior performance in comparison to control children, on all tests that measured lower and higher level processes. The cognitive planning skill was found as a predictor of the written product's spatial arrangement. The verbal intelligence predicted the written content level. Results suggest that high level processes underlie the poor quality of writing product in children with NF1. Treatment approaches for children with NF1 must include detailed assessments of cognitive planning and language skills.

Long term consistency of handwriting grip kinetics in adults

While there is growing interest in clinical applications of handwriting grip kinetics, the consistency of these forces over time is not well-understood at present. In this study, we investigated the short- and long-term intra-participant consistency and inter-participant differences in grip kinetics associated with adult signature writing. Grip data were collected from 20 adult participants using a digitizing tablet and an instrumented pen. The first phase of data collection occurred over 10 separate days within a three week period. To ascertain long-term consistency, a second phase of data collection followed, one day per month over several months. In both phases, data were collected three times a day. After pre-processing and feature extraction, nonparametric statistical tests were used to compare the within-participant grip force variation between the two phases. Participant classification based on grip force features was used to determine the relative magnitude of inter-participant versus intra-participant differences. The misclassification rate for the longitudinal data were used as an indication of long term kinetic consistency. Intra-participant analysis revealed significant changes in grip kinetic features between the two phases for many participants. However, the misclassification rate, on average, remained stable, despite different demarcations of training, and testing data. This finding suggests that while signature writing grip forces may evolve over time, inter-participant kinetic differences consistently exceeds within-participant force changes in the long-term. These results bear implications on the collection, modeling and interpretation of grip kinetics in clinical applications.

Visual-motor perception in students with attention deficit with hyperactivity disorder

PURPOSE

The aim of this study was to characterize and to compare the visual-motor perception of students with Attention Deficit with Hyperactivity Disorder (ADHD) with students with good academic performance.

METHODS

Forty students from 2nd to 5th grades of an elementary public school, male gender (100%), aged between 7 and 10 years and 8 months old participated, divided into: GI (20 students with ADHD) and GII (20 students with good academic performance), paired according to age, schooling and gender with GI. The students were submitted to Developmental Test of Visual Perception (DTVP-2).

RESULTS

The students of GI presented low performance in spatial position and visual closure (reduced motor) and inferior age equivalent in reduced motor perception, when compared to GII.

CONCLUSION

The difficulties in visual-motor perception presented by students of GI cannot be attributed to a primary deficit, but to a secondary phenomenon of inattention that interferes directly in their visual-motor performance.

Reliability of the detailed assessment of speed of handwriting on Flemish children

PURPOSE

This study evaluates the reliability of the Detailed Assessment of Speed of Handwriting (DASH) in a Dutch-speaking sample of children.

METHODS

The sample included 650 boys and 513 girls (age range = 9-16 years). Handwriting speed measurements were obtained using the DASH. Interrater agreement, test-retest reliability, and internal consistency were calculated; gender and age effects were analyzed.

RESULTS

Interrater agreement shows excellent reliability with intraclass correlation coefficients of at least 0.94. Test-retest correlations ranged from r = 0.65 to r = 0.81. The internal consistency measures, calculated with Cronbach's alpha, were between 0.88 and 0.94. Both gender and age have a significant effect on handwriting speed, with F (7.1144) = 17.43 (P < .001) for gender and F (7.1144) = 21.8 (P < .001) for age.

CONCLUSION

The DASH is a reliable assessment tool to evaluate handwriting speed of Dutch-speaking children. There is a tendency of girls to write faster than boys.

Signal-to-noise velocity peaks difference: a new method for evaluating the handwriting movement fluency in children with dysgraphia

This study evaluated handwriting movement dysfluency related to dysgraphia. A new variable, the Signal-to-Noise velocity peaks difference (SNvpd), was proposed to describe abnormal velocity fluctuations in cursive handwriting. This variable was compared to two variables most frequently used variables for assessing handwriting fluency. This comparison was carried out for three different groups, children with dysgraphia, proficient children, and adults, all of whom wrote the same single word. The adults were taken as the reference. Results revealed that, of the three variables studied, the SNvpd proved most efficient in discriminating children with dysgraphia, and that furthermore, it had the significant advantage of facilitating the localization of dysfluency peaks within a word. Our results also showed that the movement dysfluency of children with dysgraphia was specific to certain letters. In light of these results, we discuss the methodological and theoretical relevance of this new variable to the analysis of handwriting movement with the aim of characterizing dysgraphia.

Writing forces associated with four pencil grasp patterns in grade 4 children

OBJECTIVE. We investigated differences in handwriting kinetics, speed, and legibility among four pencil grasps after a 10-min copy task. METHOD. Seventy-four Grade 4 students completed a handwriting assessment before and after a copy task. Grip and axial forces were measured with an instrumented stylus and force-sensitive tablet. We used multiple linear regression to analyze the relationship between grasp pattern and grip and axial forces. RESULTS. We found no kinetic differences among grasps, whether considered individually or grouped by the number of fingers on the barrel. However, when grasps were grouped according to the thumb position, the adducted grasps exhibited higher mean grip and axial forces. CONCLUSION. Grip forces were generally similar across the different grasps. Kinetic differences resulting from thumb position seemed to have no bearing on speed and legibility. Interventions for handwriting difficulties should focus more on speed and letter formation than on grasp pattern.

Variability of grip kinetics during adult signature writing

Grip kinetics and their variation are emerging as important considerations in the clinical assessment of handwriting pathologies, fine motor rehabilitation, biometrics, forensics and ergonomic pen design. This study evaluated the intra- and inter-participant variability of grip shape kinetics in adults during signature writing. Twenty (20) adult participants wrote on a digitizing tablet using an instrumented pen that measured the forces exerted on its barrel. Signature samples were collected over 10 days, 3 times a day, to capture temporal variations in grip shape kinetics. A kinetic topography (i.e., grip shape image) was derived per signature by time-averaging the measured force at each of 32 locations around the pen barrel. The normalized cross correlations (NCC) of grip shape images were calculated within- and between-participants. Several classification algorithms were implemented to gauge the error rate of participant discrimination based on grip shape kinetics. Four different grip shapes emerged and several participants made grip adjustments (change in grip shape or grip height) or rotated the pen during writing. Nonetheless, intra-participant variation in grip kinetics was generally much smaller than inter-participant force variations. Using the entire grip shape images as a 32-dimensional input feature vector, a K-nearest neighbor classifier achieved an error rate of % in discriminating among participants. These results indicate that writers had unique grip shape kinetics that were repeatable over time but distinct from those of other participants. The topographic analysis of grip kinetics may inform the development of personalized interventions or customizable grips in clinical and industrial applications, respectively.