Implementation of the International Classification of Diseases 11th revision behavioural indicators for disorders of intellectual development with co-occurring autism spectrum disorder.

BACKGROUND: The classification of mental, behavioural and neurodevelopmental disorders in the World Health Organization's International Classification of Diseases 11th revision (ICD-11) includes a comprehensive set of behavioural indicators (BIs) within the neurodevelopmental disorders grouping. BIs can be used to assess the severity of disorders of intellectual development in situations in which standardised measures of intellectual functioning and adaptive behaviours are not available or feasible. This international study examines the implementation characteristics of the BIs and compares them to standardised measures for assessing the severity of intellectual impairment and adaptive behaviours in disorders of intellectual development and autism spectrum disorder (ASD). The clinical utility of the ICD-11 and the fidelity of its application in international clinical settings were also assessed. METHODS: A total of 116 children and adolescents (5-18 years old) with a suspected or established diagnosis of disorders of intellectual development were included across four sites [Italy (n = 18), Sri Lanka (n = 19) and two sites in India (n = 79)]. A principal component analysis was conducted to evaluate the application of the ICD-11 guidance for combining severity levels. RESULTS: Assessment using the BIs showed a higher proportion of individuals classified with mild severity, whereas the standardised measures indicated a higher proportion of severe ratings. Additionally, individuals with co-occurring ASD tended to have more severe impairments compared with those without ASD, as indicated by both BIs and standardised measures. Overall, the BIs were considered clinically useful, although more time and consideration were required when applying the guidelines for individuals with a co-occurring disorder of intellectual development and ASD. The principal component analysis revealed one principal component representing overall disorders of intellectual development severity levels. CONCLUSIONS: The ICD-11 BIs can be implemented as intended in international clinical settings for a broad range of presentations of individuals with neurodevelopmental disorders. Use of the BIs results in similar severity diagnoses to those made using standardised measures. The BIs are expected to improve the reliability of severity assessments in settings where appropriate standardised measures for intellectual and adaptive behaviours are not available or feasible.

An international field study of the ICD-11 behavioural indicators for disorders of intellectual development.

BACKGROUND: The World Health Organization (WHO) has approved the 11th Revision of the International Classification of Diseases (ICD-11). A version of the ICD-11 for Mental, Behavioural and Neurodevelopmental Disorders for use in clinical settings, called the Clinical Descriptions and Diagnostic Requirements (CDDR), has also been developed. The CDDR includes behavioural indicators (BIs) for assessing the severity of disorders of intellectual development (DID) as part of the section on neurodevelopmental disorders. Reliable and valid diagnostic assessment measures are needed to improve identification and treatment of individuals with DID. Although appropriately normed, standardised intellectual and adaptive behaviour assessments are considered the optimal assessment approach in this area, they are unavailable in many parts of the world. This field study tested the BIs internationally to assess the inter-rater reliability, concurrent validity, and clinical utility of the BIs for the assessment of DID. METHODS: This international study recruited a total of 206 children and adolescents (5-18 years old) with a suspected or established diagnosis of DID from four sites across three countries [Sri-Lanka (n = 57), Italy (n = 60) and two sites in India (n = 89)]. Two clinicians assessed each participant using the BIs with one conducting the clinical interview and the other observing. Diagnostic formulations using the BIs and clinical utility ratings were collected and entered independently after each assessment. At a follow-up appointment, standardised measures (Leiter-3, Vineland Adaptive Behaviour Scales-II) were used to assess intellectual and adaptive abilities. RESULTS: The BIs had excellent inter-rater reliability (intra-class correlations ranging from 0.91 to 0.97) and good to excellent concurrent validity (intra-class correlations ranging from 0.66 to 0.82) across sites. Compared to standardised measures, the BIs had more diagnostic overlap between intellectual and adaptive functioning. The BIs were rated as quick and easy to use and applicable across severities; clear and understandable with adequate to too much level of detail and specificity to describe DID; and useful for treatment selection, prognosis assessments, communication with other health care professionals, and education efforts. CONCLUSION: The inclusion of newly developed BIs within the CDDR for ICD-11 Neurodevelopmental Disorders must be supported by information on their reliability, validity, and clinical utility prior to their widespread adoption for international use. BIs were found to have excellent inter-rater reliability, good to excellent concurrent validity, and good clinical utility. This supports use of the BIs within the ICD-11 CDDR to assist with the accurate identification of individuals with DID, particularly in settings where specialised services are unavailable.

Symptom rating scales for schizophrenia and other primary psychotic disorders in ICD-11.

The subtype system for categorising presentations of schizophrenia will be removed from International Classification of Diseases 11th Revision. In its place will be a system for rating six domains of psychotic disorder pathology: positive symptoms, negative symptoms, depressive symptoms, manic symptoms, psychomotor symptoms and cognitive symptoms. This paper outlines the rationale and description of the proposed symptom rating scale, including current controversies. In particular, the scale could adopt either a 4-point severity rating or a 2-point presence/absence rating. The 4-point scale has the advantage of gathering more information, but potentially at the cost of reliability. The paper concludes by describing the field testing process for evaluating the proposed scale.

Effects of shade and root confinement on the expression of plagiotropic growth in juvenile-origin Douglas-fir rooted cuttings.

The purpose of this experiment was to determine why juvenile-origin Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) rooted cuttings, which remain plagiotropic (branchlike) when grown in containers in shaded glasshouses, become orthotropic (vertical) after they are transplanted to an outdoor environment. Plagiotropic rooted cuttings (mean angle from vertical = 45-50 degrees) from three full-sib families were transplanted into an outdoor nursery and subjected to four treatments consisting of a factorial of (1) shaded or unshaded and (2) bareroot or confined roots. After two growing seasons, treatments had significantly affected plant size and biomass in the order unshaded-bareroot > shaded-bareroot > unshaded-confined > shaded-confined, but plants in all treatments had become nearly orthotropic. It is concluded that neither shading nor root confinement is, but other glasshouse environmental conditions are, responsible for the persistence of plagiotropic growth.

Maturation in Douglas-fir: I. Changes in stem, branch and foliage characteristics associated with ontogenetic aging.

Two experiments were conducted to characterize changes associated with ontogenetic aging in coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and to identify possible maturation "markers" for this species. In the first experiment (Experiment 1), scions of ages 1, 4 and 9 years were collected from four seed zones in field progeny tests and grafted onto 1-year-old rootstocks. In Experiment 2, scions from five full-sib families of ages 1 and 10 years were collected from one progeny test and similarly grafted. Grafts for both experiments were planted in the field in a completely randomized design. The grafts were measured after two and six growing seasons. In Experiment 1, graft diameter, number of terminal bud flushes per year, number of branches, and branch length decreased with age. Plagiotropic angle and needle weight increased. All variables except needle length had a significant age x seed zone interaction. After 6 years, internodal stem diameters, numbers of nodal and internodal branches, and length and diameter of internodal branches decreased with age, and there were age x seed zone interactions with most variables. In Experiment 2, graft height and diameter, number of flushes, number and size of lateral branches, needle length and weight decreased with age. After 6 years, height and diameter, size and number of nodal and internodal branches, and leaf chlorophyll concentration (measured in April) decreased, but there were relatively few age x family interactions. An analysis based on traits that were significantly affected by age, but that did not interact with seed zone or family, indicated that main stem diameter, nodal branch length and nodal branch diameter were the most consistent and reliable maturation markers.