Social and community inclusion outcomes for adults with autism with and without intellectual disability in Australia.

BACKGROUND: Research suggests that adults with autism tend to have poor outcomes. Outcomes have mostly been defined using summary outcome ratings, with less focus on specific outcomes such as employment, living situation, social satisfaction, loneliness, and friendships. This study aimed to explore social and community outcomes, including employment, education, living arrangements, friendships, and social satisfaction, for autistic adults with and without intellectual disability. METHOD: Eighty-four adults with autism (mean age 34.2 years, SD = 4.5; 67% with co-occurring intellectual disability), recruited as children and adolescents, participated in the current study. Adult social and community inclusion outcomes were explored through interview and questionnaire, both parent/carer-report and self-report. RESULTS: Participants predominantly lived with family or in supported accommodation, did not pursue higher education, and mostly participated in day activity programmes. Most had limited friendships as reported by parents/carers; however, self-report data (n = 28) indicated that adults were largely satisfied with their social relationships. Overall outcome was poor for 57%, and good/very good for 34%. Adults with intellectual disability generally had poorer outcomes. CONCLUSION: Autistic adults encountered numerous difficulties in leading an independent life. Adults with co-occurring intellectual disability were most likely to experience difficulties; however, outcomes ranged from poor to very good for adults without intellectual disability. Discrepancies in parent/carer-report and self-reported experiences of friendships highlight the need to ensure individual experiences are captured in addition to parent/carer-report. Appropriate resources and programmes are crucial for adults with autism to support them to have the choice to live independently.

Coercive parenting: modifiable and nonmodifiable risk factors in parents of children with developmental disabilities.

BACKGROUND: Parents of children with developmental or intellectual disabilities tend to report greater use of coercive parenting practices relative to parents of typically developing children, increasing the risk of adverse child outcomes. However, to date, there is limited research exploring the role and relative contribution of modifiable and nonmodifiable risk factors in parents of children with a disability. The present study aimed to explore the role of various modifiable and nonmodifiable parenting, family and sociodemographic factors associated with the use of coercive parenting practices in parents of children with a disability. METHODS: Caregivers (N = 1392) enrolled in the Mental Health of Young People with Developmental Disabilities (MHYPeDD) programme in Australia completed a cross-sectional survey about their parenting and their child aged 2-12 years with a disability. Measures covered a range of domains including relevant demographic and family background, use of coercive parenting practices, intensity of child behavioural difficulties and questions relating to parent and family functioning such as parental self-efficacy, adjustment difficulties and quality of family relationships. RESULTS: Parents of older children, those who were younger at the birth of their child, and parents who were co-parenting or working reported more use of coercive parenting practices. Greater intensity of child difficulties, poorer parental self-efficacy and parent-child relationships, and more parental adjustment difficulties were also significantly associated with more use of coercive parenting. Examination of the relative contribution of variables revealed parent-child relationship was a key contributing factor, followed by intensity of child behaviour problems, parent adjustment and parent confidence. CONCLUSIONS: These findings highlight a range of factors that should be targeted and modified through upstream prevention programmes and further inform our understanding of how coercive practices may be influenced through targeted parenting interventions.

Participation in sport and physical activity in adults with intellectual disabilities.

BACKGROUND: People with intellectual disability face a number of barriers to participation in physical activity. This paper aimed to determine rates of sport and physical activity participation in an Australian sample of adults with intellectual disability, compared with rates of participation in the general Australian population. A secondary aim was to investigate factors that may contribute to participation of adults with intellectual disability. METHOD: Participants were part of the Australian Child to Adult Development (ACAD) study, consisting of a community sample with intellectual disability (n = 305), groups of adults with autism (n = 94), Down syndrome (n = 64), fragile X syndrome (n = 52), Williams syndrome (n = 45), and Prader-Willi syndrome (n = 30). Participation in sport/physical activity was reported over the past 3 months. Rates of participation were reported for adults with intellectual disability and compared with rates in a general Australian population sample. The relationship between participation in physical activity and age, degree of intellectual disability, physical mobility, living situation, socio-economic disadvantage, and behaviour and emotional problems were also conducted. RESULTS: Participants in the ACAD community sample with intellectual disability participated in sport/physical activity at lower rates than the general Australian population (42% compared with 71%). Having no physical mobility impairment was significantly associated with higher rates of participation. Those with Down syndrome participated in sport/physical activity at higher rates than the community sample with intellectual disability, while no difference in sport/physical activity participation was observed in the groups with autism or other syndromes. CONCLUSION: Australian adults with intellectual disability participate in sport and physical activity at lower rates than the general population. Having a physical mobility impairment was associated with lower rates of participation. However, people living in supported accommodation were more likely to participate than those in other living situations. Having Down syndrome was associated with a higher participation rate than the community sample.

Societal cost of childhood intellectual disability in Australia.

BACKGROUND: There is limited research quantifying the direct and indirect economic costs associated with intellectual disability (ID) in Australia. Costs incurred by families, governments and broader society include time spent providing care, absenteeism and increased healthcare utilisation. The purpose of this research is to quantify the costs associated with ID in childhood using a range of methods to collect cost data. METHODS: Costs included healthcare service utilisation, pharmaceutical use, caregiver productivity losses and time spent providing care because of the child's disability. The sample comprised caregivers with a child with ID aged between 2 and 10 years old recruited in Australia. Healthcare service utilisation and pharmaceutical use were obtained from routinely collected administrative claims data. Healthcare utilisation not captured in the routinely collected administrative data and absenteeism data were obtained from a retrospective recall-based questionnaire. Time spent providing care because of the child's disability was obtained using a time-use diary. RESULTS: The total cost of ID in Australia was estimated to be AUD 72 027 per year per child, and the total cost of ID in childhood was estimated to be AUD 12.5 billion per year. The cost to governments of ID in childhood was estimated to be AUD 6385 per child per year, resulting in a total cost to government of AUD 1.1 billion per year. CONCLUSIONS: This is the first study to estimate the direct and indirect costs associated with ID in childhood. The results of this research demonstrate the considerable economic impact of ID in childhood on families, governments and broader society in terms of both direct and indirect costs. An understanding of the cost implications of any intervention are critical in assisting policymakers in planning and prioritising of health services.

Health-related quality of life amongst primary caregivers of children with intellectual disability.

BACKGROUND: Children with intellectual disability (ID) frequently have significant educational, social and health care needs, resulting in caregivers often experiencing a wide range of negative effects. This paper aims to determine the impact of childhood ID on caregivers' health-related quality of life (HRQoL) across co-morbid diagnostic groups. The second aim of this study is to determine the risk factors associated with lower HRQoL in this population. METHODS: Caregivers of a child with ID aged between 2 and 12 years old completed an online survey to determine their HRQoL using the EQ-5D-5L measure. They were also asked demographic questions and about their dependent child's level of behavioural and emotional difficulties. RESULTS: Of the total sample of 634 caregivers, 604 caregivers completed all five questions of the EQ-5D-5L. The mean age of caregivers was 39.1 years and 91% were women. Caregivers spent on average 66.6 h per week caring for their child related to their child's disability. The mean EQ-5D-5L score of caregivers was 0.80 (95% confidence interval: 0.79, 0.82), which is below the estimated Australian population norms (mean utility score of 0.92) for the age-equivalent population. Caregivers of children with autism spectrum disorders reported the lowest HRQoL (0.77, 95% confidence interval: 0.74, 0.79) of the five included co-morbid diagnostic groups. Caregivers with a lower income, a perceived low level of social support and children with higher degree of behavioural and emotional problems were likely to have a statistically lower HRQoL. CONCLUSIONS: This is the first study to produce utility values for caregivers of children with ID. The utility values can be used to compare health states and can be used to inform comparative cost-effectiveness analyses. Demonstrating that caregivers of children with ID have reduced HRQoL and that this is associated with the degree of behavioural and emotional problems has important policy implications, highlighting the potential for policy interventions that target behavioural and emotional problems to improve outcomes for caregivers.

Concurrence of the strengths and difficulties questionnaire and developmental behaviour checklist among children with an intellectual disability.

BACKGROUND: The Strengths and Difficulties Questionnaire (SDQ) is widely used to measure emotional and behavioural problems in typically developing young people, although there is some evidence that it may also be suitable for children with intellectual disability (ID). The Developmental Behaviour Checklist - Parent version (DBC-P) is a measure of emotional and behavioural problems that was specifically designed for children and adolescents with an ID. The DBC-P cut-off has high agreement with clinical diagnosis. The aim of this study was to estimate the relationship between DBC-P and SDQ scores in a sample of children with ID. METHOD: Parents of 83 young people with ID aged 4-17 years completed the parent versions of the SDQ and the DBC-P. We evaluated the concurrent validity of the SDQ and DBC-P total scores, and the agreement between the DBC-P cut-off and the SDQ cut-offs for 'borderline' and 'abnormal' behaviour. RESULTS: The SDQ total difficulties score correlated well with the DBC-P total behaviour problem score. Agreement between the SDQ borderline cut-off and the DBC-P cut-off for abnormality was high (83%), but was lower for the SDQ abnormal cut-off (75%). Positive agreement between the DBC-P and the SDQ borderline cut-off was also high, with the SDQ borderline cut-off identifying 86% of those who met the DBC-P criterion. Negative agreement was weaker, with the SDQ borderline cut-off identifying only 79% of the participants who did not meet the DBC-P cut-off. CONCLUSION: The SDQ borderline cut-off has some validity as a measure of overall levels of behavioural and emotional problems in young people with ID, and may be useful in epidemiological studies that include participants with and without ID. However, where it is important to focus on behavioural profiles in children with ID, a specialised ID instrument with established psychometric properties, such as the DBC-P, may provide more reliable and valid information.

Syndrome specific modules to enhance the Stepping Stones Triple P public health intervention.

BACKGROUND: Service responses to behaviour phenotypes include care by expert clinicians, syndrome-specific clinics, disability-specific mental health services and generic mental health services. While these services contribute to care, they are often of limited accessibility. METHODS: We describe a population-wide public health intervention aimed at increasing the accessibility of services to the target population. Stepping Stones Triple P (SSTP) is a public health intervention of known efficacy in reducing behaviour problems when delivered to parents of children aged 0-12 with mixed developmental disabilities. RESULTS: The strategy we discuss involves enhancing SSTP with modules for specific causes of developmental disabilities including Down, Fetal Alcohol, Fragile X, Prader-Willi and Williams syndromes. CONCLUSIONS: We propose that enhancing SSTP with syndrome specific modules will increase the accessibility of support to families who have a child with a specific behaviour phenotype. We suggest that future research should confirm the public health impact of the modified SSTP programme using the RE-AIM framework.

The effect of oxytocin nasal spray on social interaction deficits observed in young children with autism: a randomized clinical crossover trial.

Interventions for autism are limited. The synthetic hormone oxytocin may provide a potential treatment to improve core social and behavioral difficulties in autism, but its efficacy has yet to be evaluated in young children who potentially may benefit to a greater extent. We investigated the efficacy, tolerability and safety of oxytocin treatment in young children with autism using a double-blind, randomized, placebo-controlled, crossover, clinical trial. Thirty-one children with autism received 12 International Units (IU) of oxytocin and placebo nasal spray morning and night (24 IU per day) for 5 weeks, with a 4-week washout period between each treatment. Compared with placebo, oxytocin led to significant improvements on the primary outcome of caregiver-rated social responsiveness. Overall, nasal spray was well tolerated, and the most common reported adverse events were thirst, urination and constipation. This study is the first clinical trial to support the potential of oxytocin as an early intervention for young children with autism to help improve social interaction deficits.

Association between adaptive behaviour and age in adults with Down syndrome without dementia: examining the range and severity of adaptive behaviour problems.

BACKGROUND: Studies on adaptive behaviour and ageing in adults with Down syndrome (DS) (without dementia) have typically analysed age-related change in terms of the total item scores on questionnaires. This research extends the literature by investigating whether the age-related changes in adaptive abilities could be differentially attributed to changes in the number or severity (intensity) of behavioural questionnaire items endorsed. METHODS: The Adaptive Behaviour Assessment System-II Adult (ABAS-II Adult) was completed by parents and caregivers of 53 adults with DS aged between 16 and 56 years. Twenty adults with DS and their parents/caregivers were a part of a longitudinal study, which provided two time points of data. In addition 33 adults with DS and their parents/caregivers from a cross-sectional study were included. Random effects regression analyses were used to examine the patterns in item scores associated with ageing. RESULTS: Increasing age was found to be significantly associated with lower adaptive behaviour abilities for all the adaptive behaviour composite scores, expect for the practical composite. These associations were entirely related to fewer ABAS-II Adult items being selected as present for the older participants, as opposed to the scores being attributable to lower item severity. CONCLUSIONS: This study provides evidence for a differential pattern of age-related change for various adaptive behaviour skills in terms of range, but not severity. Possible reasons for this pattern will be discussed. Overall, these findings suggest that adults with DS may benefit from additional support in terms of their social and conceptual abilities as they age.

Outcomes in young adulthood: are we achieving community participation and inclusion?

BACKGROUND: Despite recognition of the importance of integrated community living and support, there is evidence that parents remain the primary caregivers of young adults with intellectual disability (ID). In addition, employment rates remain low in this population. This study aimed to investigate the changes in living arrangements and participation in daytime activities over time in a community population of young people with ID. METHOD: The sample consisted of 536 participants aged 4.0-18.9 years at Wave 1, followed up at Wave 5 when aged 20.5-37.6 years. Information was collected on their living arrangements and daytime activities at both time points, along with living skills and information on community social inclusion at Wave 5. For parents still caring for their adult child with ID, information was also collected on parental ratings of their own mental and physical health, and their satisfaction with the long-term care arrangements for their adult child. RESULTS: A significant proportion of young people were still living with their parents at Wave 5. A greater proportion of those with a severe-profound degree of ID were living in residential care. Parents caring for their adult child reported high levels of mental health problems and dissatisfaction with the long-term care arrangements for their child. A small proportion of young people were in paid employment, and the majority was engaged in structured activities provided for those with an ID. Over one-third of the sample participated in a structured daytime activity for 10 or fewer hours per week, and 7% were not engaged in any structured daytime activity. CONCLUSIONS: These results suggest that adequate provision of accommodation and employment services for young adults with an ID is lacking. In many cases the responsibility of care continues to reside with parents as their children transition from childhood to adulthood. Greater attention is needed to address these issues and facilitate social inclusion and integration for young people with ID.

Functioning and post-school transition outcomes for young people with Down syndrome.

AIM: To investigate the relationship between functioning and post-school day occupation for young adults with Down syndrome. METHODS: Families of young people with Down syndrome (n = 269) aged 15-30 years in 2009 were recruited from the population-based Down syndrome 'Needs Opinion Wishes' database in Western Australia. Questionnaires were mailed to participating families and involved two parts, young person characteristics and family functioning; 203 were returned (75%). Of those families who returned questionnaires, 164 (80.8%) of their young adults had left school. Participation in post-school day occupations was the main outcome and included; open employment, training, sheltered employment or alternatives to employment (ATE). RESULTS: Young adults were reported as participating in open employment (n = 42), training (n = 17), sheltered employment (n = 64) or ATE (n = 41) post-school. Those who reported better functioning in self-care, community and communication skills were more likely to be in open employment and/or attending Technical and Further Education compared with those attending sheltered employment and/or ATE after adjusting for age, gender and rural/metropolitan regions. Current health as measured by visits to a general practitioner (GP) and hospitalizations revealed a weak relationship with post-school day occupations, with increasing likelihood of participating in open employment or training with increasing hospitalizations and GP visits. CONCLUSIONS: Our analysis shows that functioning in activities of daily living was related to post-school day occupation. Current health status and behaviour were found to have a weak relationship with post-school day occupation adjusting for functioning in the final model.

Inter-rater reliability of the Developmental Behaviour Checklist for Adults in community accommodation settings.

BACKGROUND: With the publication of the Developmental Behaviour Checklist for Adults (DBC-A), people of all ages with intellectual disability (ID) can now be assessed using a carer-completed screening checklist of emotional and behavioural disturbance. This provides a broad assessment framework across the life span, assists the process of clinical assessment, diagnosis and management, and, through efficient screening, helps ensure that people with ID and high levels of disturbed behaviour are more likely to receive the often scarce and costly behavioural and mental health services that are available. Earlier studies have reported acceptable results of test-retest reliability studies with family members and paid carers in community settings and the results of an inter-rater reliability study completed with family members. This study reports on another aspect of DBC-A reliability, inter-rater reliability with paid carers, in two small community-based accommodation settings. METHOD: Participants were 38 pairs of paid carers employed by two non-government agencies providing residential services in small group homes to 38 adults with ID in the community. RESULTS: An intraclass correlation coefficient (ICC) of 0.69 (n = 38, 95% CI 0.54-0.86) was found between pairs of paid carers employed in small group homes. DISCUSSION: Pairs of paid carers working with adults with ID in small group homes reliably completed DBC-A checklists. An ICC result of 0.69 compares favourably with the results of an earlier inter-rater study completed with the family members of people with ID living in the community. Inter-rater reliability on the six DBC-A sub-scales was also computed and the results were satisfactory. CONCLUSIONS: The carer-completed DBC-A provides a broad and comprehensive survey of the emotional and behavioural problems of adults with ID. It has satisfactory psychometric properties, which have been further extended. The DBC-A can be used in clinical, research and service settings to assess psychopathology across the adult life span in people with ID.

Behavioural and emotional problems in people with severe and profound intellectual disability.

BACKGROUND: People with severe and profound levels of intellectual disability (ID) are frequently examined as a single group in research. However, these two groups may be significantly different, particularly in the area of emotional and behavioural difficulties. METHOD: The Developmental Behaviour Checklist (DBC) was completed by parents and caregivers of 107 people with severe ID and 22 people with profound ID at four time periods across 12 years. Regression analyses were used to examine trends in sub-scale scores across time and groups. RESULTS: Significant differences between the groups of people with severe and profound ID were found. People with profound ID had significantly lower scores across all sub-scales except Social Relating. This was usually related to fewer items being selected as present for people with profound ID, as opposed to the scores being attributable to lower item severity scores. CONCLUSIONS: There are significant differences between groups of people with severe and profound ID in scores on the DBC, indicating differences in behavioural and emotional problems. Caution should be exercised by researchers treating these two disparate groups as a single group, and by practitioners translating such findings into practice.

Screening for autism in young children with developmental delay: an evaluation of the developmental behaviour checklist: early screen.

The ability to identify children who require specialist assessment for the possibility of autism at as early an age as possible has become a growing area of research. A number of measures have been developed as potential screening tools for autism. The reliability and validity of one of these measures for screening for autism in young children with developmental problems was evaluated. The parents of 207 children aged 20-51 months completed the Developmental Checklist-Early Screen (DBC-ES), prior to their child undergoing assessment. Good interrater agreement and internal consistency was found, along with significant correlations with a clinician completed measure of autism symptomatology. High sensitivity was found, with lower specificity for the originally proposed 17-item screening tool and a five-item version.

Inter-Rater Reliability of the Diagnoses of Psychosis and Depression in Individuals with Intellectual Disabilities.

BACKGROUND: There is a history of over-prescription of antipsychotics to individuals with intellectual disability (ID), while antidepressants may be under-prescribed. However, appropriate treatment is best supported when the diagnosis of psychosis or depression is valid and carries good predictive validity. The present authors report a study examining one aspect of validity, namely whether skilled clinicians can agree on whether an individual with an ID is psychotic or depressed. MATERIALS AND METHODS: Pairs of clinicians assessed 52 individuals. Agreement was assessed using Cohen's kappa statistic and agreement proportion. RESULTS: Overall agreement was high for both psychosis and depression. Whether the individual had mild ID or moderate/severe ID did not have a significant impact on agreement. CONCLUSIONS: Experienced clinicians achieved a high level of agreement as to whether a person with ID was psychotic or depressed similar to that found for those without ID. The findings provide some support for treatment interventions based on diagnosis.

Behaviour and emotional problems in toddlers with pervasive developmental disorders and developmental delay: associations with parental mental health and family functioning.

BACKGROUND: Behavioural and emotional problems occur at a high rate in children and adolescents with intellectual disability, often from a young age. Some studies have indicated that children and adolescents with autism present with even higher rates. Less is known about the presentation, development and family impact of these difficulties in young children with autism. This study aimed to explore these issues in toddlers with pervasive developmental disorders (PDDs), those with delay without a PDD, and their families. METHODS: Participants were 123 children aged 20-51 months, referred to a developmental assessment clinic. Parents completed a checklist on child behavioural and emotional problems, and individual questionnaires on family functioning, their own mental health, and stress in relation to parenting their child. The child's language and cognitive skills, adaptive functioning and behaviour were assessed by standardized measures. Measures were repeated 1 year postdiagnosis. Behavioural and emotional problems in young children with a PDD were compared with those in children with developmental delay without a PDD, and their impact on parental outcomes explored over time. RESULTS: Initial and follow-up measures of child behaviour and emotional problems, parent mental health problems, parent stress and family functioning were significantly correlated, providing some evidence of stability over time. Child emotional and behavioural problems contributed significantly more to mother stress, parent mental health problems, and perceived family dysfunction than child diagnosis (PDD/non-PDD), delay or gender. Compared with mothers, all fathers reported significantly less stress in relation to parenting their child. CONCLUSION: Results highlighted the importance of addressing emotional and behavioural problems in very young children with autism and/or developmental delay. The need for early support and intervention for mothers, fathers and families in this context was also evidenced. As research has shown that behavioural and emotional problems persist into adolescence and young adulthood, understanding of these issues in very young children and their parents has important implications for intervention and long-term outcomes.

The development of a new measure for the assessment of psychopathology in adults with intellectual disability.

BACKGROUND: People with intellectual disability (ID) and untreated psychiatric disorder lead unnecessarily difficult and unhappy lives. The prevalence of mental illness in children and adults with ID is greater than that found in the general population. A carer-completed checklist of psychopathology that could be used with both children and adults would help identify those individuals with ID most likely to have a mental health problem, help ensure that they receive the limited services that are usually available and also assist the process of clinical assessment, diagnosis and management. METHOD: This research aimed to develop a reliable and valid carer-completed checklist of psychopathology for adults with ID by redeveloping an existing measure for children with ID, the Developmental Behaviour Checklist (DBC-P). The new checklist, The Developmental Behaviour Checklist for Adults (DBC-A) was devised by changing, deleting and adding to DBC-P items. Reliability studies were conducted with paid and family carers, and DBC-A scores were compared with the results from two other measures of psychopathology. RESULTS: One DBC-P item was deleted, seven items changed and 12 items added. The psychometric properties of this new checklist, the DBC for Adults with ID (DBC-A), were investigated and found to be satisfactory. Intraclass correlations for test-retest and inter-rater reliability ranged from 0.72 to 0.85, and concurrent validity with two measures of emotional and behavioural disturbance was satisfactory. CONCLUSIONS: The carer-completed DBC-A provides a broad and comprehensive survey of the emotional and behavioural problems of adults with ID. It has satisfactory psychometric properties and therefore can be used with confidence in clinical, research and service settings, and its development allows continuous assessment of psychopathology across the lifespan for all people with ID.

Assessment of change with the Developmental Behaviour Checklist.

BACKGROUND: The Developmental Behaviour Checklist (DBC) is a 96-item instrument designed for assessing behavioural and emotional problems among young people with intellectual disability. METHODS: The present study investigated the validity of the DBC as a measure of change. Changes in individual's DBC scores were correlated with changes in expert clinicians' ratings of the same subjects. RESULTS: A high correlation was found between expert clinician ratings of change in behaviour and change in the total behaviour problem score of the DBC. CONCLUSIONS: The DBC is able to measure changes in behaviour and emotions which are recognized by an experienced clinician who is following the progress of a child with ID.

From efficacy to effectiveness: managing organisational change to improve health services for young people with deliberate self harm behaviour.

Repeat Deliberate Self Harm is a recognised risk factor for completed suicide and therefore reduction by effective health service response represents a valid contribution to suicide prevention. However, only a small fraction of people with deliberate self harm presentations to general health settings actually reach specialist mental health follow-up appointments. Therefore, even if responses at that point are known to be effective they do not make a significant contribution to reducing repeat self-harm overall. We describe health system organisational change strategies to improve health service engagement for the target group, and present data demonstrating the effectiveness of these strategies.

Longitudinal course of behavioral and emotional problems in Williams syndrome.

A follow-up study of behavior and emotional problems in a cohort of young people with Williams syndrome 5 years after first assessment is described. Using a between-/within-subjects factorial layout, we compared scores on the Developmental Behaviour Checklist between young people with Williams syndrome and a large epidemiological control sample of young people with mental retardation due to other causes from Time 1 (1990/1991) to Time 2 (1995/1996). Results showed substantial persistence of the overall level of behavior and emotional problems. However, there were changes in certain types of behavior. Participants with Williams syndrome had significantly higher overall behavioral and emotional problems, communication disturbance, and anxiety over the 5-year period. Further, 10 or 13 checklist items maintained significantly higher levels among the Williams syndrome sample.