The crucial role of the predictability of motor response in visuomotor deficits in very preterm children at school age.

AIM: We aimed to clarify the underpinnings of widespread visuomotor deficits in very preterm children. METHOD: Fifty-eight very preterm children (26 males, 32 females; mean [SD] age 7 y 6 mo [5 mo], gestational age 29.2 wks [1.6]; birthweight 1237 g [336]), recruited from a tertiary level neonatal intensive care unit, and 64 age-matched, comparison children born at term (28 males, 36 females; mean age [SD] 7 y 8 mo [7 mo]) participated. IQ was measured using a short form of the Wechsler Intelligence Scale for Children (3rd edition). A research diagnosis of developmental coordination disorder (DCD) was defined as a score below the 15th centile on the Movement Assessment Battery for Children. Visuomotor performance was assessed using a computerized task, in which children followed a predictable (structured condition) or an unpredictable (non-structured condition) trail on a touch screen using their index finger. RESULTS: Forty-six per cent of the very preterm children had a research diagnosis of DCD, compared with 16% of children born at term (p<0.001, odds ratio 4.69 [95% CI 2.01-10.99]). No group difference in visuomotor performance was present for the structured condition. In the non-structured condition, children born very preterm with and without a research diagnosis of DCD had poorer visuomotor performance than those born at term. INTERPRETATION: The predictability of the required motor response plays a crucial role in visuomotor deficits in very preterm children, regardless of DCD status.

A clinical investigation of motivation to change standards and cognitions about failure in perfectionism.

BACKGROUND: Clinical perfectionism is a transdiagnostic process that has been found to maintain eating disorders, anxiety disorders and depression. Cognitive behavioural models explaining the maintenance of clinical perfectionism emphasize the contribution of dichotomous thinking and resetting standards higher following both success and failure in meeting their goals. There has been a paucity of research examining the predictions of the models and motivation to change perfectionism. Motivation to change is important as individuals with clinical perfectionism often report many perceived benefits of their perfectionism; they are, therefore, likely to be ambivalent regarding changing perfectionism. AIMS: The aim was to compare qualitative responses regarding questions about motivation to change standards and cognitions regarding failure to meet a personal standard in two contrasting groups with high and low negative perfectionism. Negative perfectionism refers to concern over not meeting personal standards. METHOD: A clinical group with a range of axis 1 diagnoses who were elevated on negative perfectionism were compared to a group of athletes who were low on negative perfectionism. RESULTS: Results indicated that the clinical group perceived many negative consequences of their perfectionism. They also, however, reported numerous benefits and the majority stated that they would prefer not to change their perfectionism. The clinical group also reported dichotomous thinking and preferring to either keep standards the same or reset standards higher following failure, whilst the athlete group reported they would keep standards the same or set them lower. CONCLUSIONS: The findings support predictions of the cognitive behavioural model of clinical perfectionism.

Phenotype refinement for comorbid attention deficit hyperactivity disorder and reading disability.

Comorbidity between Attention Deficit Hyperactivity Disorder (ADHD) and reading disability (RD) is common; however, the heritability of this comorbidity is not well understood. This may be due to the complexity and heterogeneity of ADHD and RD phenotypes. Using alternative ADHD-RD sub-phenotypes instead of those arising from the DSM-IV may lead to greater success in the search for comorbid ADHD-RD susceptibility genes. Therefore, this study aims to refine ADHD-RD phenotypes into homogenous informative sub-phenotypes using latent class analysis (LCA). LCA was performed on 2,610 Australian twin families (6,535 individuals) in order to generate probabilistic genetically distinct classes that define ADHD-RD subtypes, including comorbidity, based on related symptom clusters. The LCA separated the phenotypes for ADHD and RD into nine classes. One class was unaffected; three classes demonstrated the three DSM-IV subtypes of ADHD, three subtypes showed different severities of RD, and two classes expressed a combination of RD and ADHD subtypes. LCA proved effective in refining the phenotypes of ADHD alone, RD alone, and ADHD-RD comorbidity, and its ability to classify them into homogenous groups based on clusters of symptoms, suggesting that the latent classes may be robust enough to use in molecular genetic studies.

Assessment of motor functioning in the preschool period.

The assessment of motor functioning in young children has become increasingly important in recent years with the acknowledgement that motor impairment is linked with cognitive, language, social and emotional difficulties. However, there is no one gold standard assessment tool to investigate motor ability in children. The aim of the current paper was to discuss the issues related to the assessment of motor ability in young pre-school children and to provide guidelines on the best approach for motor assessment. The paper discusses the maturational changes in brain development at the preschool level in relation to motor ability. Other issues include sex differences in motor ability at this young age, and evidence for this in relation to sociological versus biological influences. From the previous literature it is unclear what needs to be assessed in relation to motor functioning. Should the focus be underlying motor processes or movement skill assessment? Several key assessment tools are discussed that produce a general measure of motor performance followed by a description of tools that assess specific skills, such as fine and gross motor, ball and graphomotor skills. The paper concludes with recommendations on the best approach in assessing motor function in pre-school children.

An examination of the relationship between motor coordination and executive functions in adolescents.

AIM: Research suggests important links between motor coordination and executive functions. The current study examined whether motor coordination predicts working memory, inhibition, and switching performance, extending previous research by accounting for attention-deficit-hyperactivity disorder (ADHD) symptomatology and other confounding factors, in an adolescent normative sample. METHOD: Ninety-three adolescents (38 females, 55 males) aged 12 to 16 years (mean age 4y 2mo, SD 1y 1mo) were assessed on the Movement Assessment Battery for Children-2 (MABC-2), Wechsler Intelligence Scale for Children-IV, N-back task, the inhibition subtest from the NEPSY-II: A Developmental Neuropsychological Assessment, second edition, and the parent-rated Strengths and Weaknesses of ADHD Symptoms and Normal Behaviour Questionnaire. RESULTS: The MABC-2 total score accounted for a significant proportion of the variance in visuospatial working memory (p=0.041) but not for verbal working memory. The MABC-2 aiming and catching component, however, was found to account for unique variance in both verbal (p=0.019) and visuospatial working memory (p=0.016). The MABC-2 total score was found to account for a significant proportion of the variance in inhibition total completion time (p=0.017). Finally, balance skills accounted for unique variance in a NEPSY-II inhibition total errors variable (p=0.020). INTERPRETATION: The results provide support for an overlap between motor coordination and executive functions, which has important practical implications. The study also suggests shared mechanisms underpinning the relationship between these areas, including possible cerebellar involvement.

The revised DCDQ: is it a suitable screening measure for motor difficulties in adolescents?

The parent-rated Developmental Coordination Disorder Questionnaire (DCDQ) has been revised to incorporate a wider age range, including adolescence. In this exploratory study, internal consistency and validity of the DCDQ-2007 was assessed using a community-based sample of 87 adolescents. Psychometric properties of the DCDQ-2007 were investigated and concurrent validity, sensitivity, and specificity were assessed with the MABC-2 as a criterion standard. The results demonstrated high internal consistency for the DCDQ-2007 and a relationship with the MABC-2 was found. The DCDQ-2007 met the recommended standard for sensitivity, although the confidence interval was large; however, it failed to meet the recommended standard for specificity. This has important implications concerning the suitability of the DCDQ-2007. Although promising psychometric properties were found within the current study, the applicability of the DCDQ-2007 as a screening measure for motor difficulties requires careful consideration.

Monozygotic twins concordant and discordant for DCD: two sides to the story.

Being an identical twin does not necessarily mean having identical perceptions of family functioning, nor of the twin relationship. Using the co-twin control design, the aim of this study was to explore perceptions of family dynamics and the twin relationship in monozygotic (MZ) twins discordant and concordant for Developmental Coordination Disorder (DCD). It was hypothesized that, as has been found in twins discordant for cerebral palsy, twins without DCD would perceive family functioning as less healthy than would their co-twins with DCD. It was also hypothesized that the twin relationship would be regarded generally as mutually supportive. Questionnaire data on 866 sets of MZ twins aged 6 to 17 years were used to identify seven sets discordant, and two sets concordant for DCD. Quantitative (General Functioning Scale of the Family Assessment Device - FAD), and qualitative (semi-structured interview) measures were used to assess family dynamics and the twin relationship. In discordant sets, six of seven twins without DCD rated family functioning at a less healthy level than did their co-twins with DCD. All twins in the DCD concordant sets rated their family functioning at a healthy level. From the semi-structured interviews, emergent themes included friendship, support, minimal sibling rivalry, and minor difficulties. It was concluded that, overall, the twin relationship was regarded as close and mutually supportive, with an ambivalent polarity between the best and most difficult aspects of being an identical twin. Implications for research, policy and clinical practice are discussed.

Rationale, design and methods for a randomised and controlled trial of the impact of virtual reality games on motor competence, physical activity, and mental health in children with developmental coordination disorder.

BACKGROUND: A healthy start to life requires adequate motor development and physical activity participation. Currently 5-15% of children have impaired motor development without any obvious disorder. These children are at greater risk of obesity, musculoskeletal disorders, low social confidence and poor mental health. Traditional electronic game use may impact on motor development and physical activity creating a vicious cycle. However new virtual reality (VR) game interfaces may provide motor experiences that enhance motor development and lead to an increase in motor coordination and better physical activity and mental health outcomes. VR games are beginning to be used for rehabilitation, however there is no reported trial of the impact of these games on motor coordination in children with developmental coordination disorder. METHODS: This cross-over randomised and controlled trial will examine whether motor coordination is enhanced by access to active electronic games and whether daily activity, attitudes to physical activity and mental health are also enhanced. Thirty children aged 10-12 years with poor motor coordination (≤ 15th percentile) will be recruited and randomised to a balanced ordering of 'no active electronic games' and 'active electronic games'. Each child will participate in both conditions for 16 weeks, and be assessed prior to participation and at the end of each condition. The primary outcome is motor coordination, assessed by kinematic and kinetic motion analysis laboratory measures. Physical activity and sedentary behaviour will be assessed by accelerometry, coordination in daily life by parent report questionnaire and attitudes to physical activity, self-confidence, anxiety and depressed mood will be assessed by self report questionnaire. A sample of 30 will provide a power of > 0.9 for detecting a 5 point difference in motor coordination on the MABC-2 TIS scale (mean 17, sd = 5). DISCUSSION: This is the first trial to examine the impact of new virtual reality games on motor coordination in children with developmental coordination disorder. The findings will provide critical information to understand whether these electronic games can be used to have a positive impact on the physical and mental health of these children. Given the importance of adequate motor coordination, physical activity and mental health in childhood, this project can inform interventions which could have a profound impact on the long term health of this group of children. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000400965.

Can the Child Behavior Checklist be used to screen for motor impairment?

AIM: It has been suggested that one approach to identifying motor impairment in children is to use the Child Behavior Checklist (CBCL) as a screening tool. The current study examined the validity of the CBCL in identifying motor impairment. METHOD: A total of 398 children, 206 females and 192 males, aged from 3 years 9 months to 14 years 10 months were assessed on the McCarron Assessment of Neuromuscular Development to determine their motor ability. Parents completed the CBCL. RESULTS: The 'Clumsy' item on the CBCL was found to predict motor ability independent of the child's age, sex, and scores on other items of the CBCL. However, the sensitivity of the 'Clumsy' item in terms of identifying motor impairment was found to be a low 16.7% compared with specificity of 93.2%. The item 'Not liked' was also found to be a significant predictor of motor impairment. INTERPRETATION: Although the 'Clumsy' and 'Not liked' items were found to have a relationship with motor ability, they should not be relied upon to categorize children as motor impaired versus not impaired. It is possible that these items may be better indicators of motor impairment in children with developmental disorders such as attention-deficit-hyperactivity disorder, but clinical samples are needed to address this.

Rationale, design and methods for a randomised and controlled trial to evaluate "Animal Fun"--a program designed to enhance physical and mental health in young children.

BACKGROUND: Children with poor motor ability have been found to engage less in physical activities than other children, and a lack of physical activity has been linked to problems such as obesity, lowered bone mineral density and cardiovascular risk factors. Furthermore, if children are confident with their fine and gross motor skills, they are more likely to engage in physical activities such as sports, crafts, dancing and other physical activity programs outside of the school curriculum which are important activities for psychosocial development. The primary objective of this project is to comprehensively evaluate a whole of class physical activity program called Animal Fun designed for Pre-Primary children. This program was designed to improve the child's movement skills, both fine and gross, and their perceptions of their movement ability, promote appropriate social skills and improve social-emotional development. METHODS: The proposed randomized and controlled trial uses a multivariate nested cohort design to examine the physical (motor coordination) and psychosocial (self perceptions, anxiety, social competence) outcomes of the program. The Animal Fun program is a teacher delivered universal program incorporating animal actions to facilitate motor skill and social skill acquisition and practice. Pre-intervention scores on motor and psychosocial variables for six control schools and six intervention schools will be compared with post-intervention scores (end of Pre-Primary year) and scores taken 12 months later after the children's transition to primary school Year 1. 520 children aged 4.5 to 6 years will be recruited and it is anticipated that 360 children will be retained to the 1 year follow-up. There will be equal numbers of boys and girls. DISCUSSION: If this program is found to improve the child's motor and psychosocial skills, this will assist in the child's transition into the first year of school. As a result of these changes, it is anticipated that children will have greater enjoyment participating in physical activities which will further promote long term physical and mental health. TRIAL REGISTRATION: This trial is registered in the Australian and New Zealand Clinical trials Registry (ACTRN12609000869279).

An investigation into etiological pathways of DCD and ADHD using a monozygotic twin design.

We previously described a co-twin control design using questionnaire data on monozygotic twins discordant and concordant for developmental coordination disorder (DCD) and attention deficit hyperactivity disorder (ADHD). Our results suggested that DCD and developmental ADHD had different causal pathways, and that second-born twins were at higher risk for oxygen perfusion problems than first-born twins. In the current study we further explored our findings using DNA confirmed zygosity and assessments of 4 female and 10 male sets of monozygotic twins, aged 8 to 17 years, from the first study. Using the McCarron Assessment of Neuromuscular Development (MAND), twice as many second- as first-born twins met criteria for DCD. Second-born twins attained significantly lower scores on 1-minute Apgar, MAND Gross Motor, Bimanual Dexterity and Neuromuscular Development Index. Seven of the nine twins who met criteria for DCD experienced perinatal oxygen perfusion problems. This supported findings in the first study of an association between perinatal oxygen perfusion problems and DCD, and our hypothesis that DCD and cerebral palsy have similar causal pathways. We found similar numbers of males and females discordant for DCD. On telephone interview using the Diagnostic Interview Schedule for Children Parent Interview, the only first-, and all five second-born twins who met criteria for ADHD had an inattentive component - three Inattentive; three Combined. All twins positive for ADHD were male. This adds support to our hypothesis that ADHD symptoms found in some participants may reflect secondary ADHD associated with environmental factors, rather than developmental ADHD.

Rationale, design and methods for a randomised and controlled trial to investigate whether home access to electronic games decreases children's physical activity.

BACKGROUND: Many children are reported to have insufficient physical activity (PA) placing them at greater risk of poor health outcomes. Participating in sedentary activities such as playing electronic games is widely believed to contribute to less PA. However there is no experimental evidence that playing electronic games reduces PA. There is also no evidence regarding the effect of different types of electronic games (traditional sedentary electronic games versus new active input electronic games) on PA. Further, there is a poor understanding about how characteristics of children may moderate the impact of electronic game access on PA and about what leisure activities are displaced when children play electronic games. Given that many children play electronic games, a better understanding of the effect of electronic game use on PA is critical to inform child health policy and intervention. METHODS: This randomised and controlled trial will examine whether PA is decreased by access to electronic games and whether any effect is dependent on the type of game input or the child's characteristics. Children aged 10-12 years (N = 72, 36 females) will be recruited and randomised to a balanced ordering of 'no electronic games', 'traditional' electronic games and 'active' electronic games. Each child will participate in each condition for 8 weeks, and be assessed prior to participation and at the end of each condition. The primary outcome is PA, assessed by Actical accelerometers worn for 7 days on the wrist and hip. Energy expenditure will be assessed by the doubly labelled water technique and motor coordination, adiposity, self-confidence, attitudes to technology and PA and leisure activities will also be assessed. A sample of 72 will provide a power of > 0.9 for detecting a 15 mins difference in PA (sd = 30 mins). DISCUSSION: This is the first such trial and will provide critical information to understand whether access to electronic games affects children's PA. Given the vital importance of adequate PA to a healthy start to life and establishing patterns which may track into adulthood, this project can inform interventions which could have a profound impact on the long term health of children. TRIAL REGISTRATION: This trial is registered in the Australia and New Zealand Clinical Trials Registry (ACTRN 12609000279224).

Motor development in very preterm and very low-birth-weight children from birth to adolescence: a meta-analysis.

CONTEXT: Infants who are very preterm (born < or = 32 weeks of gestation) and very low birth weight (VLBW) (weighing < or = 1500 g) are at risk for poor developmental outcomes. There is increasing evidence that very preterm birth and VLBW have a considerable effect on motor development, although findings are inconsistent. OBJECTIVE: To investigate the relationship between very preterm birth and VLBW and motor development. DATA SOURCES: The computerized databases EMBASE, PubMed, and Web of Knowledge were used to search for English-language peer-reviewed articles published between January 1992 and August 2009. STUDY SELECTION: Studies were included if they reported motor scores of very preterm and VLBW children without congenital anomalies using 1 of 3 established and widely used motor tests: the Bayley Scales of Infant Development II (BSID-II), the Movement Assessment Battery for Children (MABC), and the Bruininks-Oseretsky Test of Motor Proficiency (BOTMP). Forty-one articles were identified, encompassing 9653 children. RESULTS: In comparison with term-born peers, very preterm and VLBW children obtained significantly lower scores on all 3 motor tests: BSID-II: d = -0.88 (95% confidence interval [CI], -0.96 to -0.80; P < .001), MABC: d = -0.65 (95% CI, -0.70 to -0.60; P < .001), and BOTMP: d = -0.57 (95% CI, -0.68 to -0.46; P < .001). Whereas motor outcomes on the BSID-II show a catch-up effect in the first years of development (r = 0.50, P = .01), the results on the MABC demonstrate a nonsignificantly greater deficit with increasing age during elementary school and early adolescence (r = -0.59, P = .07). CONCLUSION: Being born preterm or VLBW is associated with significant motor impairment persisting throughout childhood.

Does 'Animal Fun' improve aiming and catching, and balance skills in young children?

AIM: The Animal Fun program, a universal early intervention program that aims to promote the motor skills and social-emotional development of young children, has shown to improve overall motor proficiency and social and behavioural outcomes. The aim of the current study was to evaluate the program's impact on children's aiming and catching, and balance skills. METHODS: A cluster randomised control trial was employed, with six intervention and six control (following normal curriculum) schools. A total sample of 511 children (257 boys and 254 girls), aged 4-6 years presented at pre-test. Children were tested across three time points, pre-test, post intervention (six months later) and follow-up (18 months after pre-test), using the Movement Assessment Battery for Children-2 Aiming and Catching, and Balance tasks. The study also tested for potential moderators including pre-test motor proficiency, age, gender, and cognitive performance. RESULTS: Participation in Animal Fun improved children's one leg balance at post-test and follow-up compared to control children, regardless of pre-test motor proficiency, age, gender, or pre-test cognitive performance. Participation in Animal Fun also improved throwing skills for those children with poorer motor proficiency compared to the controls with poorer motor performance. Interestingly, it was found that the control group's catching skills improved more than the intervention group at follow up. CONCLUSIONS: The study provides some promising results regarding the efficacy of the Animal Fun program in improving one-leg balance for all children, and throwing skills for those children with poorer motor proficiency, while also suggesting potential confounding factors, such as maturational issues and other individual factors (e.g., a child's participation in extracurricular activity).

Effect of postural instability on drawing errors in children: a synchronized kinematic analysis of hand drawing and body motion.

To investigate the role that postural stability plays in fine motor control, we assessed kinematics of the head, shoulder, elbow, and the pen during an accuracy drawing task in 24 children. Twelve children were classified into an accurate drawing (AD) group and 12 children into an inaccurate drawing (ID) group based on a manual dexterity task from the movement assessment battery for children [Henderson, S. E., & Sugden, D. A. (1992). Movement assessment battery for children. London: Psychological Corporation.]. Their parents completed a questionnaire to assess children's inattention, hyperactivity, and impulsivity. An electromagnetic tracking system was used to monitor 3-D kinematic data of the body parts, while 2-D kinematic data of pen movement was simultaneously collected from a computer digitizer tablet. If a sudden body motion (1cm/s) occurred within a time window from one second prior to the onset of the drawing error to the end of the error, we considered that the error coincided with the extraneous body movement. For each drawing trial, the coincidence rate was computed as (number of coincidences)/(number of errors). The ID group had a significantly higher coincidence rate of head and shoulder movements compared with elbow movements, whereas coincidence rates did not differ between the three body parts in the AD group. Parental ratings of children's behavioral ratings of inattention, hyperactivity, and impulsivity were not correlated with the coincidence rates. The results indicated that inaccurate drawing was a result of postural instability rather than fidgeting caused by inattention or hyperactivity/impulsivity.

The role of early fine and gross motor development on later motor and cognitive ability.

The aim of this study was to determine whether information obtained from measures of motor performance taken from birth to 4 years of age predicted motor and cognitive performance of children once they reached school age. Participants included 33 children aged from 6 years to 11 years and 6 months who had been assessed at ages 4 months to 4 years using the ages and stages questionnaires (ASQ: [Squires, J. K., Potter, L., & Bricker, D. (1995). The ages and stages questionnaire users guide. Baltimore: Brookes]). These scores were used to obtain trajectory information consisting of the age of asymptote, maximum or minimum score, and the variance of ASQ scores. At school age, both motor and cognitive ability were assessed using the McCarron Assessment of Neuromuscular Development (MAND: [McCarron, L. (1997). McCarron assessment of neuromuscular development: Fine and gross motor abilities (revised ed.). Dallas, TX: Common Market Press.]), and the Wechsler Intelligence Scale for Children-Version IV (WISC-IV: [Wechsler, D. (2004). WISC-IV integrated technical and interpretive manual. San Antonio, Texas: Harcourt Assessment]). In contrast to previous research, results demonstrated that, although socio-economic status (SES) predicted fine motor performance and three of four cognitive domains at school age, gestational age was not a significant predictor of later development. This may have been due to the low-risk nature of the sample. After controlling for SES, fine motor trajectory information did not account for a significant proportion of the variance in school aged fine motor performance or cognitive performance. The ASQ gross motor trajectory set of predictors accounted for a significant proportion of the variance for cognitive performance once SES was controlled for. Further analysis showed a significant predictive relationship for gross motor trajectory information and the subtests of working memory and processing speed. These results provide evidence for detecting children at risk of developmental delays or disorders with a parent report questionnaire prior to school age. The findings also add to recent investigations into the relationship between early motor development and later cognitive function, and support the need for ongoing research into a potential etiological relationship.

The relationship between motor skills and psychosocial factors in young children: A test of the elaborated environmental stress hypothesis.

BACKGROUND: The elaborated environmental stress hypothesis (EESH) provides a framework that describes how motor skills may indirectly cause internalizing problems through various mediating psychosocial factors. While there is evidence to support this framework, little is known about how the proposed relationships may vary across different stages of development. AIMS: This study aimed to investigate whether peer problems and perceived self-competence mediated the relationship between motor skills and internalizing problems in pre-primary children, and at 18-month follow up. SAMPLE: A community sample of 197 pre-primary school children (M = 5.40 years, SD = 0.30 years; 102 males, 95 females) participated at Time 1, with 107 completing the Time 2 follow-up. METHODS: Standardized instruments were used to measure motor skills and verbal IQ. Perceived self-competence was measured using a self-report measure. Participant peer problems and internalizing problems were measured using teacher report. Age, gender, and verbal IQ were included as covariates. RESULTS: Mediation analysis using PROCESS showed that the relationship between motor skills and internalizing problems was mediated by peer problems at Time 1. At Time 2, the relationship was mediated by peer problems and perceived physical competence. CONCLUSIONS: The current results indicate the EESH may function differently across different periods of development. The transition from pre-primary to Grade 1 represents a time of important cognitive and psychosocial development, which has implications for how the relationship between motor skills and internalizing problems can be understood. These findings highlight potential age-appropriate targets for psychomotor interventions aiming to improve the emotional well-being of young children.

The role of dichotomous thinking and rigidity in perfectionism.

Perfectionism is a complex psychological construct that has been defined in many different ways. Recent conceptualisations of perfectionism have involved dividing the construct into positive and negative components. Negative perfectionism is associated with high emotional distress whereas positive perfectionism is associated with positive affect and lower levels of distress. Although these distinctions have been made it remains unclear as to how distinct the two aspects of perfectionism are particularly in terms of their cognitive profiles. This study investigated two cognitive constructs that have been theoretically linked to perfectionism. Dichotomous thinking and rigidity were examined in three samples (40 clinical participants, 111 athletes, 101 students). As hypothesised, the clinical sample had the highest score on negative perfectionism, however, no differences were observed between groups on positive perfectionism. Dichotomous thinking emerged as the variable most predictive of negative perfectionism, and was less strongly related to positive perfectionism. These results highlight the importance of dichotomous thinking as a cognitive construct worthy of further research to understand negative perfectionism. Implications for the development of cognitive therapy interventions for negative perfectionism are discussed.

Depressive symptomatology in child and adolescent twins with attention-deficit hyperactivity disorder and/or developmental coordination disorder.

Previous research has demonstrated a link between attention-deficit/hyperactivity disorder (ADHD), developmental coordination disorder (DCD), and depression. The present study utilized a monozygotic (MZ) differences design to investigate differences in depressive symptomatology between MZ twins discordant for ADHD or DCD. This extends previous research as it controls for genetic effects and shared environmental influences and enables the investigation of nonshared environmental influences. In addition, children and adolescents with comorbid ADHD and DCD were compared on their level of depressive symptomatology to those with ADHD only, DCD only, and no ADHD or DCD. The parent-rated Strengths and Weaknesses of ADHD Symptoms and Normal Behavior, Developmental Coordination Disorder Questionnaire, and Sad Affect Scale were used to assess ADHD, DCD, and depressive symptomatology respectively. The results revealed higher levels of depressive symptomatology in MZ twins with ADHD or DCD compared to their nonaffected co-twins. In addition, children and adolescents with comorbid ADHD and DCD demonstrated higher levels of depressive symptomatology compared to those with ADHD only, DCD only, and no ADHD or DCD. The implications of these findings are discussed with emphasis on understanding and recognizing the relationship between ADHD, DCD, and depression in the assessment and intervention for children and adolescents with these disorders.