Evaluating an adapted reverse categorisation task to assess cognitive flexibility in young children with Down syndrome.

BACKGROUND: Accurate measurement of cognitive skills is necessary to advance both developmental and intervention science for individuals with Down syndrome (DS). This study evaluated the feasibility, developmental sensitivity and preliminary reliability of a reverse categorisation measure designed to assess cognitive flexibility in young children with DS. METHODS: Seventy-two children with DS ages 2.5-8 years completed an adapted version of a reverse categorisation task. Twenty-eight of the participants were assessed again 2 weeks later for retest reliability. RESULTS: This adapted measure demonstrated adequate feasibility and developmental sensitivity, and preliminary evidence for test-retest reliability when administered to children with DS in this age range. CONCLUSIONS: This adapted reverse categorisation measure may be useful for future developmental and treatment studies that target early foundations of cognitive flexibility in young children with DS. Additional recommendations for use of this measure are discussed.

Psychometric properties of inhibitory control measures among youth with Down syndrome.

BACKGROUND: Inhibitory control measures have been commonly used when assessing individuals with Down syndrome. However, minimal attention has been devoted to evaluating the appropriateness of specific assessments for use in this population, potentially leading to erroneous conclusions. This study aimed to examine the psychometric properties of measures of inhibitory control among youth with Down syndrome. We sought to examine the feasibility, presence of floor or practice effects, test-retest reliability, convergent validity and correlations with broader developmental domains of a set of inhibitory control tasks. METHODS: A sample of 97 youth with Down syndrome aged 6 to 17 years old participated in verbal and visuospatial tasks of inhibitory control including the Cat/dog Stroop, Neuropsychological Assessment Second Edition (NEPSY-II) Statue, National Institutes of Health (NIH) Toolbox Cognition Battery (TCB) Flanker, Leiter-3 Attention Sustained, and the Test of Attentional Performance for Children (KiTAP) Go/No-go and Distractibility subtests. Youth also completed standardised assessments of cognition and language, and caregivers completed rating scales. Psychometric properties on the tasks of inhibitory control were evaluated against a priori criteria. RESULTS: Apart from demonstrating negligible practice effects, adequate psychometric properties were not observed for any inhibitory control measure within the current sample's age range. One task with low working memory demands (NEPSY-II Statue) generally had better psychometric properties than the other tasks assessed. Subgroups of participants with an IQ greater than 30 and age more than 8 years were shown to be more likely to be able to complete the inhibition tasks. CONCLUSIONS: Findings suggest better feasibility for analogue tasks rather than computerised assessments of inhibitory control. Given the weak psychometrics of several common measures, future studies are required to evaluate other inhibitory control measures, specifically those with reduced working memory demands for youth with Down syndrome. Recommendations for use of the inhibitory control tasks among youth with Down syndrome are provided.

Confirmatory factor analysis of the BRIEF2 in a sample of youth with Down syndrome.

BACKGROUND: The factor structure of the Behavior Rating Inventory of Executive Function, second edition (BRIEF2) has been widely examined in both typically developing children and specific clinical samples. Despite the frequent use of the BRIEF2 for measuring executive functioning in individuals with Down syndrome, no study has investigated the factorial validity or dimensionality of the BRIEF2 in this population. This study aimed to address this notable gap in the literature. METHODS: Parents of 407 children and youth with Down syndrome aged 6-18 years completed the BRIEF2 as part of different studies led by six sites. Three competing models proposed by previous studies were analysed using Confirmatory Factor Analysis: the theoretical structure of the BRIEF2 where the scales were constrained to load on three factors labelled as Cognitive, Behavioral, and Emotional Regulation, a two-factor correlated model with the merged Behavioral and Emotional regulation, and a single-factor model. RESULTS: The three-factor model provided a better fit than the one- and two-factor models, yet a large correlation was observed between Behavioural and Emotional regulation factors. The results provide meaningful explanatory value for the theoretical structure of the BRIEF2. However, the Behavioral and Emotional regulation factors might be less differentiated and the two-factor structure of the BRIEF2 may also make theoretical and empirical sense. CONCLUSIONS: Although more studies are needed to further examine the factor structure of the BRIEF2 in youth with Down syndrome, this investigation provides preliminary support for the interpretation of the three executive function index scores provided by the BRIEF2: Cognitive, Behavioral, and Emotional Regulation.

Latent profiles of autism symptoms in children and adolescents with Down syndrome.

BACKGROUND: Down syndrome (DS) is associated with elevated rates of autism spectrum disorder (ASD) and autism symptomatology. To better characterise heterogeneity in ASD symptomatology in DS, profiles of caregiver-reported ASD symptoms were modelled for children and adolescents with DS. METHODS: Participants (n = 125) were recruited through several multi-site research studies on cognition and language in DS. Using the Social Responsiveness Scale-2 (SRS-2; Constantino and Gruber 2012), two latent profile analyses (LPA) were performed, one on the broad composite scores of social communication and interaction and restricted interests and repetitive behaviour, and a second on the four social dimensions of social communication, social motivation, social awareness, and social cognition. RESULTS: A three-profile model was the best fit for both analyses, with each analysis yielding a low ASD symptom profile, an elevated or mixed ASD symptom profile and a high ASD symptom profile. Associations were observed between profile probability scores and IQ, the number of co-occurring biomedical conditions reported, sex, and SRS-2 form. CONCLUSIONS: Characterising heterogeneity in ASD symptom profiles can inform more personalised supports in this population, and implications for potential therapeutic approaches for individuals with DS are discussed.

Evaluating working memory outcome measures for children with Down syndrome.

BACKGROUND: There is a critical need for the psychometric evaluation of outcome measures to be used in clinical trials targeting cognition in Down syndrome (DS). This study examines a specific cognitive skill that is of particular importance in DS, working memory, and the psychometric properties of a set of standardised measurements to assess working memory in individuals with DS. METHODS: Ninety children and adolescents ages 6 to 18 years old with DS were assessed on a selection of verbal and visuospatial working memory subtests of standardised clinical assessments at two time points to examine feasibility, distributional qualities, test-retest reliability and convergent validity against a priori criteria. Caregivers also completed an adaptive behaviour questionnaire to address working memory subtests' associations with broader developmental functioning. RESULTS: The Stanford Binet-5 Verbal Working Memory, Differential Ability Scales-2 Recognition of Pictures, Stanford Binet-5 Nonverbal Working Memory and Wechsler Intelligence Scale for Children-5 Picture Span measures met the most psychometric criteria overall across the full age and IQ range of the study. Although Differential Ability Scales-2 Recall of Sequential Order and Differential Ability Scales-2 Recall of Digits Backward met the fewest a priori criteria, follow-up analyses suggested greater feasibility in specific age and IQ ranges. CONCLUSIONS: Several working memory measures appear to be psychometrically sound and appropriate for use in clinical trials for children with DS, especially when focusing on raw scores. However, floor effects on standard scores and feasibility of some measures were problematic. Guidelines for use of the working memory subtests with this population are provided.

Co-occurring medical and behavioural conditions in children with Down syndrome with or without ADHD symptom presentation.

BACKGROUND: Co-occurring attention deficit hyperactivity disorder (ADHD) is a challenge to characterise in the presence of other medical conditions commonly present in children with Down syndrome (DS). The current study examined differences among children with DS with or without ADHD symptomatology in terms of demographics, developmental level, co-occurring medical conditions, and parent and teacher ratings of behaviour and executive functioning. METHODS: Parents and teachers of 108 school-age children with DS provided ratings of ADHD symptoms, behaviour problems and executive functioning skills. Children with DS and ADHD symptom presentation, as identified by a scoring algorithm, were compared with those without ADHD symptom presentation on demographic characteristics, developmental level, co-occurring medical conditions and parent-report and teacher-report measures of behaviours and executive functioning. RESULTS: Sleep disorders, disruptive behaviour disorder, allergies and seizures were more common in children with DS and ADHD symptom presentation than in children without ADHD symptom presentation. After controlling for ADHD medication use, children with DS and ADHD symptom presentation had poorer performance than those without ADHD symptom presentation on parent behaviour ratings, teacher behaviour ratings and parent but not teacher ratings of executive functioning. No significant group differences in demographic characteristics or developmental level were identified. CONCLUSIONS: Higher rates of co-occurring medical conditions present in children with DS and ADHD symptom presentation support the need for thorough differential diagnoses. The different pattern of group differences between parent-report and teacher-report has implications for diagnostic practices across settings as well as for treatment.

Reliability of parent report measures of behaviour in children with Down syndrome.

BACKGROUND: Behavioural problems are common among children with Down syndrome (DS). Tools to detect and evaluate maladaptive behaviours have been developed for typically developing children and have been evaluated for use among children with intellectual and developmental disabilities. However, these measures have not been evaluated for use specifically in children with DS. This psychometric evaluation is important given that some clinically observed behaviours are not addressed in currently available rating scales. The current study evaluates the psychometric properties of the Child Behavior Checklist (CBCL), a commonly used screening tool developed for typically developing children and commonly used with children with intellectual and developmental disabilities. METHODS: The study investigated the psychometric properties of the CBCL among school-aged children with DS, including an assessment of the rate of detecting behaviour problems, concerns with distribution, internal consistency, inter-rater reliability and convergent and discriminant validity with the Aberrant Behavior Checklist and Nisonger Child Behavior Rating Form. Caregivers of 88 children with DS aged 6-18 years rated their child's behaviour with the CBCL, Aberrant Behavior Checklist and Nisonger Child Behavior Rating Form. Teachers completed the Teacher Report Form. RESULTS: About one-third of children with DS were reported to exhibit behaviours of clinical concern on the total score of the CBCL. Internal consistency for CBCL sub-scales was poor to excellent, and inter-rater reliability was generally acceptable. The sub-scales of the CBCL performed best when evaluating convergent validity, with variable discriminant validity. Normative data conversions controlled for age and gender differences in this sample. CONCLUSIONS: The study findings suggest that, among children with DS, some CBCL sub-scales generally performed in a psychometrically sound and theoretically appropriate manner in relation to other measures of behaviour. Caution is warranted when interpreting specific sub-scales (Anxious/Depressed, Somatic Complaints and Thought Problems). The CBCL can continue to be used as a screening measure when evaluating behavioural concerns among children with DS, acknowledging poor discriminant validity and the possibility that key behaviour concerns in DS may not be captured by the CBCL screen.

Impact of sleep on executive functioning in school-age children with Down syndrome.

BACKGROUND: Sleep problems have an impact on executive functioning in the general population. While children with Down syndrome (DS) are at high risk for sleep problems, the impact of these sleep problems on executive functioning in school-age children with DS is less well documented. Our study examined the relationship between parent-reported and actigraphy-measured sleep duration and sleep quality with parent and teacher reports and neuropsychology assessments of executive functioning among school-age children with DS. METHOD: Thirty school-age children with DS wore an actigraph watch for a week at home at night. Their parent completed ratings of the child's sleep during that same week. Children completed a neuropsychology assessment of their inhibitory control, ability to shift and working memory. Their parents and teachers completed rating scales to assess these same constructs of executive functioning. RESULTS: Parent reports of restless sleep behaviours on the Children's Sleep Habits Questionnaire (CSHQ), but not actigraph-measured sleep period or efficiency, were predictive of parent reports of concerns with inhibitory control, shifting and working memory, and of teacher reports of inhibitory control. No measure of sleep was predictive of executive functioning as measured by the neuropsychology assessment. CONCLUSION: The study findings corroborate the preliminary literature that parent-reported sleep problems are related to executive functioning in school-age children with DS, particularly in the area of inhibitory control across home and school. These findings have implications for understanding contributing factors to academic performance and school behaviour in school-age children with DS.

Convergent validity of actigraphy with polysomnography and parent reports when measuring sleep in children with Down syndrome.

BACKGROUND: There is a need for rigorous measures of sleep in children with Down syndrome as sleep is a substantial problem in this population and there are barriers to obtaining the gold standard polysomnography (PSG). PSG is cost-prohibitive when measuring treatment effects in some clinical trials, and children with Down syndrome may not cooperate with undergoing a PSG. Minimal information is available on the validity of alternative methods of assessing sleep in children with Down syndrome, such as actigraphy and parent ratings. Our study examined the concurrent and convergent validity of different measures of sleep, including PSG, actigraphy and parent reports of sleep among children with Down syndrome. METHOD: A clinic (n = 27) and a community (n = 47) sample of children with Down syndrome were examined. In clinic, children with Down syndrome wore an actigraph watch during a routine PSG. In the community, children with Down syndrome wore an actigraph watch for a week at home at night as part of a larger study on sleep and behaviour. Their parent completed ratings of the child's sleep during that same week. RESULTS: Actigraph watches demonstrated convergent validity with PSG when measuring a child with Down syndrome's total amount of sleep time, total wake time after sleep onset and sleep period efficiency. In contrast, actigraph watches demonstrated poor correlations with parent reports of sleep, and with PSG when measuring the total time in bed and total wake episodes. Actigraphy, PSG and parent ratings of sleep demonstrated poor concurrent validity with clinical diagnosis of obstructive sleep apnoea. CONCLUSION: Our current data suggest that actigraph watches demonstrate convergent validity and are sensitive to measuring certain sleep constructs (duration, efficiency) in children with Down syndrome. However, parent reports, such as the Children's Sleep Habits Questionnaire, may be measuring other sleep constructs. These findings highlight the importance of selecting measures of sleep related to target concerns.

Links between sleep and daytime behaviour problems in children with Down syndrome.

BACKGROUND: In the general population, sleep problems have an impact on daytime performance. Despite sleep problems being common among children with Down syndrome, the impact of sleep problems on daytime behaviours in school-age children with Down syndrome is an understudied topic. Our study examined the relationship between parent-reported and actigraphy-measured sleep duration and sleep quality with parent and teacher reports of daytime behaviour problems among school-age children with Down syndrome. METHOD: Thirty school-age children with Down syndrome wore an actigraph watch for a week at home at night. Their parent completed ratings of the child's sleep during that same week. Their parent and teacher completed a battery of measures to assess daytime behaviour. RESULTS: Parent reports of restless sleep behaviours on the Children's Sleep Habits Questionnaire, but not actigraph-measured sleep efficiency, was predictive of parent and teacher behavioural concerns on the Nisonger Child Behaviour Rating Form and the Vanderbilt ADHD Rating Scales. Actigraph-measured sleep period and parent-reported sleep duration on the Children's Sleep Habits Questionnaire was predictive of daytime parent-reported inattention. Actigraph-measured sleep period was predictive of parent-reported hyperactivity/impulsivity. CONCLUSION: The study findings suggest that sleep problems have complex relationships to both parent-reported and teacher-reported daytime behaviour concerns in children with Down syndrome. These findings have implications for understanding the factors impacting behavioural concerns and their treatment in school-age children with Down syndrome.

Reliability of parent report measures of sleep in children with Down syndrome.

BACKGROUND: Behavioural sleep disturbances are common among children with Down syndrome (DS). However, tools used to detect and evaluate behavioural sleep disturbances were developed for typically developing children and have not been evaluated for use among children with DS. The current study evaluates the psychometric properties of three measures of behavioural sleep disturbances that are currently being used with children with intellectual and developmental disabilities, including children with DS. METHOD: Caregivers of 30 children with DS rated their child's sleep with the Behavioral Evaluation of Disorders of Sleep (BEDS), Children's Sleep Habits Questionnaire (CSHQ) and Sleep Disturbances Scale for Children (SDSC). Caregivers also provided information on sleep diagnoses and completed a 7-night sleep and behaviour diary. RESULTS: The study investigated the rate of detecting sleep problems, internal consistency, and convergent and concurrent validity of the BEDS, CSHQ and SDSC. Children with DS were reported to exhibit behavioural sleep disturbances at different rates depending on the measure used; 0% BEDS, 79.3% CSHQ and 17.2% SDSC. Internal consistency was comparable for all three measures for their total scores. However, when evaluating the internal consistency of subscale scores, those on the CSHQ and SDSC performed more strongly. The subscales of the CSHQ performed best when evaluating convergent and concurrent validity, with the SDSC subscales performing moderately well. CONCLUSION: The study findings suggest that, among children with DS, the CSHQ and its subscales performed in a psychometrically sound and theoretically appropriate manner in relation to other measures of sleep, medical history of sleep problems, and daily reports of sleep and associated behaviours. The SDSC performed moderately well. When evaluating behavioural sleep disturbances among children with DS, the CSHQ is recommended based on its stronger psychometric properties.

Sleep problems and associated comorbidities among adults with Down syndrome.

BACKGROUND: Sleep problems, including sleep apnoea and behavioural sleep disturbances, are common among adults with Down syndrome (DS). Despite a preliminary understanding of potential medical and behavioural comorbidities of these sleep problems among children with DS, little is known about comorbid conditions associated with these sleep problems among adults with DS. Understanding causes and sequelae of sleep problems in this ageing population is essential to providing quality health screening and treatment. The current study examines the physical health problems, mental health conditions, functional abilities and behavioural problems associated with sleep apnoea and behavioural sleep disturbances among adults with DS. METHOD: Family caregivers participated in clinical interviews and completed questionnaires, providing reports regarding 75 adults with DS. Caregivers reported on sleep problems, physical and mental health conditions, daily living skills and behaviours regarding their ageing family member with DS. RESULTS: Sleep apnoea was associated with more common other respiratory concerns, and more frequent visits to physicians, but not with some expected medical comorbidities (cardiac). Behavioural sleep disturbances (delayed sleep onset, night-time awakenings and morning awakenings) were associated with poorer health, more frequent overnight hospital and emergency department visits, more common cardiac conditions, less common thyroid condition, more common mental health conditions (anxiety, depression and dementia) and a higher rate of daytime behaviour problems. CONCLUSION: The study findings suggest that there are differential correlates for the various sleep problems in adults with DS, which warrant attention when screening for medical and mental health comorbidities, assessing behavioural problems and in treatment planning for ageing adults with DS.

Fine motor and self-care milestones for individuals with Down syndrome using a Retrospective Chart Review.

BACKGROUND: Developmental milestone markers for fine motor and self-care skills among children with Down syndrome (DS) are either minimal, anecdotal or out-of date. Our goal was to produce normative expectations for the development of fine motor and self-care milestones specific to children with DS. METHOD: A cross-sectional retrospective chart review was completed on 274 children with DS seen at a specialty clinic that ranged in age from 4 months to 18 years. Specific skills were assessed at occupational therapy assessments as either present or absent, including fine motor, handwriting, scissor usage, self-feeding and clothing management. RESULTS: Fine motor milestones describing when 10-30% ('early achievers') and 75-95% ('representative achievement') of children with DS had mastered each skill were developed based upon descriptive review. As the fine motor and self-care skills advanced in complexity, the range of ages for documented skill acquisition was observed to increase. CONCLUSIONS: Age ranges for the mastery of fine motor developmental milestones for early and representative achievement were developed based upon descriptive analysis of cross-sectional retrospective clinical chart reviews. That the age range for mastering fine motor and self-care skills broadens as children with DS get older is in agreement with what is identified in the DS behavioural phenotype with regard to variable motor skills overall. These fine motor and self-care developmental milestone markers contribute to the field by informing parents, caregivers and healthcare providers of potential fine motor and self-care outcomes and describing normative development for children with DS.

Factors predicting mortality in midlife adults with and without Down syndrome living with family.

BACKGROUND: Little is known about the mortality of individuals with Down syndrome who have lived at home with their families throughout their lives. The current study evaluates the predictors, causes and patterns of mortality among co-residing individuals in midlife with Down syndrome as compared with co-residing individuals with ID owing to other causes. METHOD: This paper examines mortality in 169 individuals with and 292 individuals without Down syndrome from 1988 to 2007. Dates and causes of death were obtained from maternal report, the Social Security Death Index and the National Death Index. Risk factors predicting mortality, including demographic variables, transition variables, and initial and change measures of health, functional abilities and behaviour problems, were obtained from maternal report. RESULTS: Having Down syndrome is a risk factor of mortality, net of other risk factors including older age, poorer functional abilities, worsening behaviour problems, residential relocation and parental death. The causes of death among individuals with and without Down syndrome who are in midlife and co-residing with their families are similar, and are most commonly due to cardiovascular or respiratory problems. CONCLUSIONS: The findings indicate that midlife adults with Down syndrome who co-reside with their families generally exhibit similar causes of mortality as do midlife adults with intellectual disability owing to other causes, but show an elevated risk of mortality in midlife net of other variables, such as age and changes in functional abilities and behaviour problems.

An evaluation of Beck's cognitive theory of depression in adults with intellectual disability.

BACKGROUND: The theories supporting cognitive treatment for depression among individuals with intellectual disability (ID) have not been formally tested with this population. The current study evaluated Beck's cognitive theory of depression to determine its appropriateness for adults with ID. METHODS: Forty-eight adults with primarily mild or moderate ID participated in semi-structured interviews, twice approximately 16 weeks apart, as did an additional 12 adults diagnosed with depression. Participants reported on depressed mood, the cognitive triad, as measured by views of the self, the world and the future, hopelessness and self-esteem. RESULTS: The Cognitive Triad Inventory for Children (CTI-C) displayed adequate psychometric properties in this sample. In addition, it was correlated with depressed mood, and individuals diagnosed with depression had significantly higher scores on the CTI-C than those with no psychiatric diagnoses. Contrary to hypotheses, a negative cognitive triad did not predict depressed mood 4 months later, but the inverse relationship where depressed mood predicted a later negative cognitive triad approached statistical significance. CONCLUSIONS: The findings indicate that the cognitive triad can be measured among individuals with mild or moderate ID and is related to depression and depressed mood. However, the role of the cognitive triad in the development of depression is still unknown. The findings provide some support for Beck's cognitive theory of depression among individuals with ID and provide suggestions for further testing the theory. Implications for the treatment of depression among individuals with ID are discussed.

A prospective analysis of life events, problem behaviours and depression in adults with intellectual disability.

BACKGROUND: Life events have consistently been found to be associated with behaviour problems and depression among individuals with intellectual disability (ID). However, prior findings have typically been based on correlational or retrospective analyses of case files. The current study attempted to replicate prior findings from life events with concurrent data and extend them to the prospective prediction of behaviour problems and depression. The influence of impact ratings of life events was also explored. METHODS: Seventy-four informants rated 104 adults with ID on measures of life events, behaviour problems and depressive symptoms. Life events were rated as having either a positive, negative or no impact on the life of the individual with ID. Measures were completed twice, at a 4-month interval. RESULTS: Behaviour problems were both correlated with and predicted by frequency counts of life events and life events perceived as negative. However, the predictive ability depended on which measure of problem behaviour was selected. Positive life events were not associated with concurrent behaviour problems. Depressive symptoms were correlated with all life changes, but only predicted by frequency counts of life events and life events perceived as negative. Again, the predictive ability depended on which measure of depression was selected. Findings were corroborated with a group of individuals with clinical diagnoses of major depression. CONCLUSIONS: Frequency counts of all life events and life events perceived as negative play a role in the development of behaviour problems and depressive symptoms among adults with ID. The results have implications for interventions for behaviour problems following a life event, and for reducing depressive symptoms for adults with mild ID.

Cognitive variables and depressed mood in adults with intellectual disability.

BACKGROUND: Cognitive theory forms the foundation for cognitive therapy. There has been little research on cognitive theories and cognitive variables associated with depression in individuals with intellectual disability (ID). The current study examined cognitive variables of automatic thoughts, cognitive triad, hopelessness, attributions and self-esteem associated with two cognitive theories of depression: Beck's Cognitive Triad theory and the Hopelessness theory of depression. METHODS: Seventy-three adults with ID screened for adequate receptive vocabulary were interviewed as part of a larger study. They reported on cognitive constructs relating to depressed mood. In addition, comparisons were made between 12 adults with ID and diagnosed major depression and a matched group of 12 adults with ID and no psychiatric diagnoses in order to determine if these groups differed on the cognitive constructs associated with the two cognitive theories of depression. RESULTS: The cognitive variables examined were all significantly correlated with depressed mood in the direction predicted by their respective cognitive theory. Internal consistencies were good or excellent for most instruments, with the exception of those measuring hopelessness and attributions. In addition, significant differences were obtained between groups of individuals with and without co-morbid major depression on all variables except for hopelessness. CONCLUSIONS: The results indicate that adults with ID screened for adequate receptive vocabulary are capable of reporting on subjective feelings of depressed mood and associated cognition constructs. The instruments used may be suitable for this population as they generally possessed sound internal consistencies. The results support the further examination of cognitive theories of depression among individuals with ID in order to assess the appropriateness of cognitive therapies for this population. Discrepant findings regarding hopelessness are discussed.

The Behavior Problems Inventory: an instrument for the assessment of self-injury, stereotyped behavior, and aggression/destruction in individuals with developmental disabilities.

The Behavior Problems Inventory (BPI-01) is a 52-item respondent-based behavior rating instrument for self-injurious, stereotypic, and aggressive/destructive behavior in mental retardation and other developmental disabilities. Items are rated on a frequency scale and a severity scale. The BPI-01 was administered by interviewing direct care staff of 432 randomly selected residents from a developmental center between the ages of 14 to 91 years. For 73% of those selected, at least one problem was endorsed on the BPI-01. A total of 43% showed self-injury, 54% stereotyped behavior, and 38% aggressive/destructive behavior. Confirmatory factor analysis and item-total correlations supported the three a priori factors. Analyses of variance (ANOVA) showed that of the variables age, sex, and level of mental retardation, only the latter had a significant effect on the BPI-01 total score, the SIB subscale score, and the Stereotyped Behavior subscale score. Aggression/destruction was not significantly related to any of the three variables. Individuals with a diagnosis of pervasive developmental disorder had higher scores on all three subscales than those without, whereas residents with a diagnosis of stereotyped movement disorder had higher Stereotyped Behavior scale scores than those without. The BPI-01 was found to be a reliable (retest reliability, internal consistency, and between-interviewer-agreement) and valid (factor and criterion validity) behavior rating instrument for problem behaviors in mental retardation and developmental disabilities with a variety of potentially useful applications. Strengths and limitations of the instrument are discussed.