Deficits In Adaptive Behavior Research Articles

Inclusive learning and development practices for children with autism spectrum disorders and the ICT’s role

Nowadays, the inclusive orientation of education has promoted the inalienable right of all children, including those with autism spectrum disorders (ASD), to be educated in mainstream schools alongside their typically developing (TD) peers. The autism spectrum includes developmental disorders that appear in early childhood and are characterized by qualitative deficits in social communication and adaptive behavior, impeding academic learning and social-emotional development. The aim of this paper is to study those practices that form the conditions for realizing the functional inclusion of ASD children in the traditional classroom. For this reason, through the literature review of modern foreign language scientific articles, an attempt was made to search and study the most widespread and research-documented intervention procedures and techniques, which develop the readiness skills of ASD children, providing them with quality opportunities for active learning and socialization alongside their TD peers. The results showed that when the earlier targeted educational approaches are used in the inclusive classroom, in a structured and predictable learning environment, taking into account their unique characteristics, interests and assessed educational needs, with the support of adequately trained teachers and an interdisciplinary team, in cooperation with the family, their dynamic involvement in the activities of the school program is facilitated. Furthmore, quality interactions with their TD peers are increased and therefore, the appearance of socially acceptable behaviors is promoted, which contributes to their acceptance by their classmates, laying the foundations for their smooth integration into society.

Adaptive behaviour deficits in individuals with 3q29 deletion syndrome.

3q29 deletion syndrome (3q29del) is associated with a significantly increased risk for neurodevelopmental and neuropsychiatric phenotypes. Mild to moderate intellectual disability (ID) is common in this population, and previous work by our team identified substantial deficits in adaptive behaviour. However, the full profile of adaptive function in 3q29del has not been described nor has it been compared with other genomic syndromes associated with elevated risk for neurodevelopmental and neuropsychiatric phenotypes. Individuals with 3q29del (n=32, 62.5% male) were evaluated using the Vineland Adaptive Behaviour Scales, Third Edition, Comprehensive Parent/Caregiver Form (Vineland-3). We explored the relationship between adaptive behaviour and cognitive function, executive function, and neurodevelopmental and neuropsychiatric comorbidities in our 3q29del study sample, and we compared subjects with 3q29del with published data on fragile X syndrome, 22q11.2 deletion syndrome and 16p11.2 deletion and duplication syndromes. Individuals with 3q29del had global deficits in adaptive behaviour that were not driven by specific weaknesses in any given domain. Individual neurodevelopmental and neuropsychiatric diagnoses had a small effect on adaptive behaviour, and the cumulative number of comorbid diagnoses was significantly negatively associated with Vineland-3 performance. Both cognitive ability and executive function were significantly associated with adaptive behaviour, and executive function was a better predictor of Vineland-3 performance than cognitive ability. Finally, the severity of adaptive behaviour deficits in 3q29del was distinct from previously published data on comparable genomic disorders. Individuals with 3q29del have significant deficits in adaptive behaviour, affecting all domains assessed by the Vineland-3. Executive function is a better predictor of adaptive behaviour than cognitive ability in this population and suggests that interventions targeting executive function may be an effective therapeutic strategy.

Intellectual functioning and adaptive behaviour in children with Dravet syndrome: A population-based study.

To identify, on a population basis, the prevalence of intellectual disability in children with Dravet syndrome, profiles on a measure of adaptive behaviour, and factors associated with intellectual functioning and adaptive behaviour. Forty-two out of 48 children with Dravet syndrome living in Sweden, born between 1st January 2000 and 31st December 2018, underwent assessment of intellectual functioning and adaptive behaviour. Factors associated with level of intellectual functioning and adaptive behaviour were analysed. Eight-six per cent (n= 36) of the children fulfilled DSM-5 criteria for intellectual disability (29% [n= 12] mild intellectual disability, 24% [n= 10] moderate intellectual disability, 33% [n= 14] severe intellectual disability, 0% profound intellectual disability) and 93% (n= 39) had an adaptive behaviour composite more than two standard deviations below the mean. Communication was a significant weakness compared with daily living skills (p< 0.001; mean difference 95% confidence interval [CI] -8.193 to -4.092) and socialization (p= 0.001; mean difference 95% CI 6.511 to -1.775) on the Vineland Adaptive Behavior Scales, Second Edition. The only factors significantly associated with both decreased adaptive behaviour and presence of severe intellectual disability was the presence of increased autistic symptoms and younger age. Children with Dravet syndrome have a very high level of intellectual disability and almost all have significant deficits in adaptive behaviour. Greater deficits in adaptive behaviour and greater severity of intellectual disability are associated with the presence of increased autistic symptoms, highlighting the need for comprehensive neurodevelopmental assessment for all affected children. Eighty-six per cent (n=36) of children with Dravet syndrome fulfilled criteria for intellectual disability. Ninety-three per cent (n=39) of children with Dravet syndrome had significant deficits in adaptive behaviour. Communication was a significant weakness on a measure of adaptive behaviour. Increased autistic symptoms were associated with greater deficits in cognition/adaptive behaviour. Older age and earlier status epilepticus were associated with decreased adaptive behaviour.

Effects of central amygdala chemogenetic manipulation and prior chronic alcohol exposure on Pavlovian-to-instrumental transfer.

Recent work suggests that a history of chronic alcohol exposure can enhance the influence of nondrug reward cues on ongoing actions. This is often modeled in Pavlovian-to-instrumental transfer (PIT) tasks that examine the interaction between Pavlovian and instrumental learning processes, usually reflected as an increase in action vigor during the presentation of a reward-associated cue. Though prior chronic alcohol exposure strengthens this type of cue-guided behavior, the neural mechanisms underlying such enhancements are not known. In the present work, we examined the contribution of the central amygdala (CeA), a region strongly implicated in PIT behaviors and functionally altered by chronic alcohol exposure. We utilized Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) to examine the impact of inhibitory and excitatory CeA manipulation on PIT behaviors in alcohol-naïve mice and mice with a history of chronic intermittent ethano vapor exposure and withdrawal (CIE). Replicating previous work, we found that a history of CIE strengthened baseline PIT, in the absence of any CeA manipulation. We also found that activation of both inhibitory and excitatory DREADDs expressed in CeA enhanced PIT in alcohol-naïve mice, though the latter markedly reduced response rates. However, in mice exposed to CIE, activation of excitatory DREADD receptors expressed in CeA appeared to weaken PIT. These results suggest that alcohol-induced disruptions in amygdala function may contribute to changes in appetitive behaviors, such as cue-guided responding, following chronic exposure to alcohol. Better elucidating the neural mechanisms that underlie disrupted cue-guided behavior following chronic alcohol exposure may help to understand and treat deficits in adaptive behavior associated with chronic alcohol use in humans.

Cognitive and Psychological Outcomes Following Pediatric Cardiac Arrest.

Cardiac arrest is a rare event in children and adolescents. Those who survive may experience a range of outcomes, from good functional recovery to severe and permanent disability. Many children experience long-term cognitive impairment, including deficits in attention, language, memory, and executive functioning. Deficits in adaptive behavior, such as motor functioning, communication, and daily living skills, have also been reported. These children have a wide range of neurological outcomes, with some experiencing specific deficits such as aphasia, apraxia, and sensorimotor deficits. Some children may experience emotional and psychological difficulties, although many do not, and more research is needed in this area. The burden of pediatric cardiac arrest on the child's family and caregivers can be substantial. This narrative review summarizes current research regarding the cognitive and psychological outcomes following pediatric cardiac arrest, identifies areas for future research, and discusses the needs of these children for rehabilitation services and academic accommodations.

Attention Deficit/Hyperactivity Disorder Symptoms Impair Adaptive and Social Function in Children With Autism Spectrum Disorder.

Background: Autism spectrum disorder (ASD) often co-exists with attention deficit/hyperactivity disorder (ADHD), which may aggravate functional impairment. However, it is unclear how comorbid ADHD symptoms influence the adaptive behavior and social interaction deficits of children with ASD.Methods: The study enrolled 340 children (ranging from 2 to 14 years) with ASD, with comorbid ASD and ADHD, or with typical development (TD). A psychological evaluation involving adaptive behavior and social function was conducted using the Vineland Adaptive Behavior Scale, Second Edition (VABS-II) and the Social Responsiveness Scale (SRS).Results: There was a high prevalence of ADHD symptoms (46.6%) in children with ASD, and children with ASD + ADHD presented the worse profile of ASD symptoms. The ASD + ADHD group had higher scores on VABS and lower scores on SRS in comparison with the ASD alone group and TD group. The regression analysis revealed that ASD symptoms and ADHD symptoms were significantly associated with greater impairments in adaptive behavior and social function. The ADHD symptoms were responsible for an additional 0.8% of the variance in adaptive behavior, and 9.5% of the variance in social function.Conclusions: More severe ASD symptoms and greater impairment in adaptive function and social ability were found in children with ASD and comorbid ADHD, highlighting the need to identify ADHD comorbidities early on in children with ASD and to reduce their negative impact on functioning.

A SYSTEMATIC REVIEW OF TEACHERS PERCEPTIONS TOWARDS EFFECTIVE TEACHING-LEARNING OF STUDENTS WITH INTELLECTUAL DISABILITY

The phrase intellectual impairment refers to a persons level of cognitive functioning. By specific children it occurs when a childs cognitive functioning is hampered to the extent that he or she is unable to receive information from his or her environment. After that, successfully absorbing, problem-solving, and adapting to the knowledge is required. The purpose of this study is to provide an overview of children with intellectual disability and their education for conceptual knowledge, define cause, and classify. Intellectual disability is defined as significant deficits in intellectual functioning and adaptive behaviour manifested as conceptual, social, and practical adaptive skills. An intellectual disability is characterized as having an IQ of less than 70 and having problems with adaptive behaviour or daily living abilities (eating, dressing, communicating, and participating in group activities). Intellectually disabled people learn slowly and have trouble grasping abstract concepts. So there is a dire need of appropriate teaching methodologies for effective Teaching-Learning of such students. The features of people with intellectual disability according to their education are also discussed in this study.

Mental retardation and oral health: An insight

Mental Retardation (MR) is a genetic disorder mainfested in significantly below average overall intellectual functioning and deficits in adaptive behaviour. It is a particular state of functioning that begins in childhood and is characterized by decreased intelligence and adaptive skills and also is the most common developmental disorder, often missed by clinicians. The condition is present in 2 to 3 percent of the population, either as an isolated finding or as part of a syndrome or broader disorder. Looking at varies studies it was concluded that the oral health situation of these groups must be improved and a suitable system devised for delivery of preventive measures. Special consideration must be given to improving the oral health of these groups. Oral health should be included in each child’s individual health care plan with oral health promotion programmes aimed specifically at special needs schools and their parents. Children should be instructed to clean their teeth twice a day and oral hygiene should be practised at school and supervised by teachers. There should be a provision for in-service training for teachers, school staff and parents on how to promote good oral health specifically for these children with disabilities.

Adaptive Behavior of College Students With Autism

As an increasing number of individuals with autism spectrum disorder (ASD) matriculate on college campuses, all stakeholders should be prepared to meet their needs. Despite a body of literature describing adaptive behavior deficits of individuals with ASD, there is a paucity of research examining these skills among those who are college-ready. The present study investigated the adaptive behavior of a diverse group ( N = 27) of incoming college students with ASD and examined to what extent these skills could predict initial academic success. Despite average intelligence and good academic indicators, deficits in communication, socialization, and daily living skills were found. No models, even those that included intelligence quotient (IQ) and SAT scores, were predictive of first-semester or first-year grade point average (GPA). Importantly, freshman-to-sophomore retention appeared higher than the university average. Findings suggest that practitioners and families should consider adaptive behavior in addition to intellectual and academic capabilities when considering postsecondary opportunities and available supports.

Altered Gene Expression Profiles in Neural Stem Cells Derived from Duchenne Muscular Dystrophy Patients with Intellectual Disability.

Intellectual disability (ID) is a neurodevelopmental disorder defined by below-average intelligence (intelligence quotient of <70) accompanied by adaptive behavior deficits. Defects in the functions of neural stem cells during brain development are closely linked to the pathogenesis of ID. To understand the molecular etiology of ID, we examined neural stem cells from individuals with Duchenne muscular dystrophy (DMD), a genetic disorder in which approximately one-third of the patients exhibit ID. In this study, we generated induced pluripotent stem cells from peripheral blood mononuclear cells from a normal individual and DMD patients with and without ID to identify ID-specific functional and molecular abnormalities. We found defects in neural ectoderm formation in the group of DMD patients with ID. Our transcriptome analysis of patient-derived neural stem cells revealed altered expression of genes related to the hippo signaling pathway and neuroactive ligand-receptor interaction, implicating these in the pathogenesis of ID in patients with DMD.

Developmental Perspectives on the Study of Persons with Intellectual Disability.

Developmental approaches provide inclusive, universal, and methodologically rigorous frameworks for studying persons with intellectual disability (ID). This is an exceptionally heterogeneous group with regard to etiology, genotype, and phenotype that simply shares the traditional diagnostic criteria, typically a score of two standard deviations below the population mean of 100 on standardized IQ tests and deficits in adaptive behavior. We trace the foundational, conceptual, and methodological roots of developmental approaches and highlight ways that these and more recent iterations continue to be central to advances in the increasingly nuanced study of persons with ID. This work is premised on the consideration of specific etiological groupings and subgroupings across and between different domains of functioning within the context of familial and complex environments throughout the life span. We highlight the potential contributions of advances in behavioral methodologies, genomics, and neuroscience when considered within universal and hierarchic frameworks based on development.

Symptoms of Autism Spectrum Disorder in Children With Down Syndrome and Williams Syndrome.

Research suggests that people with a Williams syndrome (WS) or Down syndrome (DS) diagnosis display an increased prevalence of autism spectrum disorder (ASD) when compared to the general population. This study aimed to examine characteristics of ASD in a group of children with DS or WS. Results suggest that children with DS and WS exhibit higher levels of autism symptoms than the general population, particularly in the area of unusual behaviors, and that these elevations are not solely due to deficits in adaptive behavior. There are many possible explanations for these elevations, such as issues with measurement, etiological overlap, or similar behavioral phenotypes. More research is needed to further our understanding of the overlap of ASD symptoms in these populations.

Speech Impairments Explain Unique Variance in Adaptive Behavior Skills in Young People With Down Syndrome.

Background Down syndrome (DS) is a disorder characterized by impairments in global cognitive abilities and adaptive function. In addition, individuals with DS demonstrate pronounced speech and language deficits. However, little is known about the linguistic correlates of impaired adaptive functioning in DS. Method Using the Adaptive Behavior Assessment System-Second Edition and the Children's Communication Checklist-Second Edition (CCC-2), this study investigated the unique variance in adaptive skills accounted for by speech and language impairments in individuals with DS (N = 29, M age = 13.46). Results Pearson correlations revealed that a composite of CCC-2 structural language scales, but not pragmatic language scales, was significantly correlated with the Adaptive Behavior Assessment System-Second Edition Global Adaptive Composite, Conceptual, and Practical domains. Further investigation utilizing hierarchical regression analyses identified only the Speech scale on the CCC-2 as contributing unique variance to the prediction of adaptive behavior scores in the Global Adaptive Composite, Conceptual, and Practical domains. Conclusion Speech impairments may serve as flags to identify children with DS who are at risk for adaptive behavior deficits and reinforce the need for speech-language therapies that focus on speech for these individuals. Supplemental Material https://doi.org/10.23641/asha.13231985.

Evidence of validity and reliability of the adaptive functioning scale for intellectual disability (EFA-DI)

Intellectual disability (ID) is a developmental disorder characterized by deficits in intellectual functioning and adaptive behavior. The fifth edition of the Diagnostic and statistical manual of mental disorders (DSM-5) defines adaptive functioning as a severity measure of ID. The availability of tests in the international context to assess this construct has increased in recent years. In Brazil, however, non-systematic assessment of adaptive functioning, such as through observation and interviews, still predominates. The Escala de Funcionamento Adaptativo para Deficiência Intelectual EFA-DI [Adaptive Functioning Scale for Intellectual Disabilities] is a new instrument developed in Brazil to assess the adaptive functioning of 7- to 15-year-old children and support the diagnosis of ID. This study’s objectives were to investigate evidence of validity related to the EFA-DI’s internal structure, criterion validity, and reliability. The psychometric analyses involved two statistical modeling types, confirmatory factor analysis (CFA) and item response theory analysis (IRT). These results highlight the EFA-DI scale’s strong psychometric properties and support its use as a parental report measure of young children’s adaptive functioning. Future studies will be conducted to develop norms of interpretation for the EFA-DI. This study is expected to contribute to the fields of psychological assessment and child development in Brazil.

Autism and Employment: Implications for Employers and Adults with ASD.

A small but growing body of research has been conducted on vocational outcomes for adults with Autism Spectrum Disorder (ASD); however, limited resources have been directed towards understanding outcomes for competitive employers. While ASD does present with a range of social communication and adaptive behaviordeficits, adults on the spectrum may be extremely efficient, trustworthy, reliable, and cost-effective employees. Nevertheless, fewer than half of young adults with ASD maintain a job. Many businesses are unwilling to hire these capable candidates, concerned among other things about an increase in supervision costs and a decrease in productivity. This is a bias based on misperceptions; the financial and social benefits of hiring adults with ASD, for businesses and the individual, often outweigh the costs.

Randomized Placebo-controlled Double-blind Clinical Trial on the Efficacy of AYUSHMANAS in the Management of Smritidaurbalya (Cognitive Deficit)

Background: According to modern medicine, individuals whose general intellectual functioning is significantly below average and concurrently having deficits in adaptive behavior are considered to be having cognitive deficit. It may be congenital or caused by factors such as brain injuries, neurological disorders, or mental illness. In Ayurveda, the condition can be correlated with Manasamandata. Various terms are used in the classics like Buddhimandyata, Jadata, Smritidaurbalya, etc., to denote impairment of intellectual functions. The current medications for cognitive deficit in modern medicine are not entirely satisfactory, so many patients seek alternative treatment for its management. Thus, there is a definite need to scientifically assess some of alternative treatment modalities. Objective: To assess the efficacy and safety of a coded Ayurvedic drug-AYUSHMANAS-in children suffering from cognitive deficit. Materials and methods: This is a prospective, randomized, double-blind, two-arm placebo-controlled clinical study. A total of 150 participants (75 in each arm) suffering with cognitive deficit will be included in line with inclusion and exclusion criteria. The participants of trial group will be administered with AYUSHMANAS (250 mg × 2 tablets) while in control group Placebo (250 mg × 2 tablets) will be administered twice daily after food for 180 days. A total of seven visits will be scheduled for each participant: first visit at screening day 0, 30th day, 60th day, 90th day, 120th day, 150th day, and 180th day. The outcomes intended from the study include observing changes in Binet Kamat test of intelligence (BKT) and mini-mental state examination (MMSE) and a modified MMSE (mMMSE) scores apart from assessing safety of the intervention. Observation of therapeutic and safety endpoint outcomes will be undertaken. Discussion: This clinical protocol is designed for exploring a better clinical outcome with good safety profile in the management of cognitive deficit in children. If found effective, the selected drug can be listed in the management protocol of cognitive deficit at clinical practice level in terms of better efficacy, safety, and cost-effective intervention. The selected drug may also lead to better understanding and management of cognition related problems. Trial registration: CTRI/2019/07/020324

Neurobehavioral phenotype of autism spectrum disorder associated with germline heterozygous mutations in PTEN

Germline mutations in PTEN, the gene that encodes phosphatase and tensin homolog, have been identified in up to 20% of children with autism spectrum disorder (ASD) and macrocephaly and are associated with marked abnormalities in the white matter of the brain. This study sought to characterize the neurobehavioral phenotype of PTEN-ASD. Comprehensive neurobehavioral evaluations were conducted in 36 participants (ages 3–21 years) with PTEN-ASD and compared to two groups of controls: non-syndromic ASD with macrocephaly (Macro-ASD, n = 25) and those with PTEN mutations without ASD (PTEN-no ASD, n = 23). Linear regression analysis or Kruskal–Wallis tests were used to examine group differences on neurobehavioral measures (cognitive, behavioral, sensory, and adaptive functioning) and, for select measures, one-sample t-tests were used to compare group performance to healthy control norms. These analyses revealed a distinct neuropsychological profile associated with mutations in PTEN suggesting primary disruption of frontal lobe systems (i.e., attention, impulsivity, reaction time, processing speed, and motor coordination). Cognitive deficits in PTEN-ASD are more severe than those in PTEN-no ASD and extend to other areas of neurobehavioral function, specifically, adaptive behavior and sensory deficits. While core ASD symptoms are similar in PTEN-ASD and Macro-ASD, PTEN-ASD had lower clinical ratings of autism severity and showed more sensory abnormalities suggestive of less sensory responsiveness. Together, these results suggest that PTEN-ASD has a distinct neurobehavioral phenotype compared to idiopathic ASD that is likely to warrant special consideration for overall assessment and treatment.

Relationship between the Vineland Adaptive Behaviour Scales and the Wechsler Adult Intelligence Scale IV in adults with intellectual disabilities.

Diagnoses of intellectual disability (ID) are based on three criteria: significant impairments in intellectual functioning, concurrent deficits in adaptive behaviour, and both being acquired in the developmental period. Adaptive behaviour was formally incorporated into the diagnosis in 1959; the rationale being that IQ and adaptive behaviour were different constructs that independently contribute to the diagnosis. However, there are limited data on the relationship between IQ and adaptive behaviour and especially so for adults who have ID. The aim of this study was to investigate this relationship on two widely used assessment tools: the Wechsler Adult Intelligence Scale - fourth edition (WAIS-IV) and the Vineland Adaptive Behaviour Scales (VABS). Data were extracted from the case files of 147 adults who had a formal diagnosis of ID based on the WAIS-IV and VABS. Internal consistency was computed and compared to general population data. Correlations between the WAIS-IV and the VABS were computed. Internal consistencies for the tests when used with adults who have ID were generally good. The correlations between the WAIS-IV and VABS composite and subdomain scores were all low and similar to those reported for the general population. These results suggest that the WAIS-IV and VABS are measuring different constructs that contribute to the diagnosis of ID. Unfortunately, by the time such data have been collected, tests are being revised. The Vineland has now been revised and is in its third edition, but no data on the relationship between IQ and the VABS were collected during test development. The WAIS-V is now in development, and so it is recommended that such work be incorporated into this process or shortly thereafter to ensure that the tools continue to access independent constructs.

Adaptive functioning in children with neurofibromatosis type 1: relationship to cognition, behavior, and magnetic resonance imaging.

To characterize the adaptive behavior profile of children with neurofibromatosis type 1 (NF1) and determine its relationship to neuropsychological functioning and non-neoplastic T2-weighted hyperintense brain lesions on brain magnetic resonance imaging (MRI). In this cross-sectional study, we retrospectively reviewed neuropsychological reports from 104 children with NF1 (56 males, 48 females; mean age 10y 4mo; standard deviation [SD] 3y 4mo; range 3y 5mo-17y 6mo), and extracted data from a range of cognitive and behavioral measures, including the Adaptive Behavior Assessment System (ABAS). Brain MRI was retrospectively reviewed in 42 individuals. Adaptive Behavior Assessment System scores were continuously distributed and pathologically shifted by 0.79 to 1.26SD across Conceptual, Social, and Practical domains, and 46.5% of individuals had a composite score in the borderline or impaired range. Impairment in adaptive functioning was correlated with deficits in executive function (r=-9.543, p<0.001), externalizing problems (r=-0.366, p<0.001), and attention (r=-9.467, p=0.001). Cluster analysis revealed three distinct phenotypic subgroups, one of which exhibited normal cognitive ability, but impaired adaptive functioning, with persistent deficits in executive function, behavioral problems, and attention-deficit/hyperactivity disorder symptomatology. There was no relationship between ABAS scores and the number or location of unidentified bright objects. Adaptive functioning deficits are common among children with NF1 and are associated with impairment in other cognitive/behavioral domains, independent of general cognitive ability. Deficits in adaptive behavior are common in children with neurofibromatosis type 1 (NF1). Poor adaptive functioning is associated with impairments in executive function, externalizing behaviors, and attention, regardless of cognitive ability. The presence or location of unidentified bright objects do not predict adaptive behavior skills in children with NF1.

Developing behavioural indicators for intellectual functioning and adaptive behaviour for ICD-11 disorders of intellectual development.

We present the work conducted to arrive at deriving behavioural indicators that could be used to guide clinical judgement in determining the presence and severity of deficits in intellectual functioning and adaptive behaviour for the purpose of making a diagnosis of disorders of intellectual development. An interdisciplinary expert panel provided guidance in developing behavioural indicators for intellectual functioning. A national dataset of adaptive behaviour on a sample of individuals with a diagnosis of intellectual disability was used to develop the behavioural indicators for the adaptive behaviour. The adaptive behaviour data were analysed using a cluster analysis procedure to define the different severity groupings by chronological age groups. We present a series of tables containing behavioural indicators across the lifespan for intellectual functioning and adaptive behaviour, including conceptual, social and practical skills. These tables of behavioural indicators have been proposed for use in the clinical version of the 11th revision of the International Classification of Diseases and Related Health Problems (ICD-11) to be published by the World Health Organization. The proposed behavioural indicators for disorders of ID described in the present article and to be included in the ICD-11 Clinical Descriptions and Diagnostic Guidelines are put forth to assist professionals in making an informed clinical decision regarding an individual's level of intellectual functioning and adaptive behaviour for the purpose of making a determination about the presence and severity of disorders of ID.