Informant-based assessment instruments for dementia in people with intellectual disability: A systematic review and standardised evaluation.

BACKGROUND: Dementia in people with intellectual disability (ID) is frequent but hard to recognise. Evidence-based recommendations for suitable instruments are lacking. AIMS: The present study set out to evaluate informant-based dementia assessment instruments and to provide evidence-based recommendations for instruments most suitable in clinical practice and research. METHOD AND PROCEDURES: A systematic review was conducted across ten international electronic databases. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines, including a risk of bias assessment, was applied to extract information and to evaluate measurement properties and the quality of available evidence. OUTCOMES AND RESULTS: In total, 42 studies evaluating 18 informant-based assessment instruments were analysed. For screening purposes, we recommend the Behavioral and Psychological Symptoms of Dementia in Down Syndrome Scale (BPSD-DS), the Cognitive Scale for Down Syndrome (CS-DS), and the Dementia Screening Questionnaire for Individuals with Intellectual Disabilities (DSQIID). For a more thorough dementia assessment, we recommend the Cambridge Examination for Mental Disorders of Older People with Down's Syndrome and Others with Intellectual Disabilities (CAMDEX-DS). CONCLUSIONS AND IMPLICATIONS: Our study informs clinicians and researchers about adequate, well-evaluated dementia assessment instruments for people with ID, and highlights the need for high quality studies, especially regarding content validity.

[Cognition in Down's Syndrome: Development across the Life Span and Neuropsychological Assessment in Adults]. / Kognition bei Down-Syndrom: Entwicklung über die Lebensspanne und neuropsychologische Diagnostik im Erwachsenenalter.

Down's syndrome is the most frequent genetic cause of intellectual disability. As the risk for developing Alzheimer's disease is increased in Down's syndrome, comprehensive cognitive examination is essential, both in young adults (for baseline evaluation), as well as later for diagnosing dementia. So far, there are only a few recommendations for neuropsychological assessment in Down's syndrome. Here, we review (1) the development of cognition across the life span, (2) various causes of cognitive change in adults with Down's syndrome, and (3) procedures available for their evaluation. Furthermore, (4) we provide recommendations for the assessment and interpretation of diagnostic findings in adults with intellectual disabilities. We conclude with recommendations for cognitive assessment in intellectual disability in general.