Reliability and Validity of the Supports Intensity Scale (SIS) Measured in Adults with Physical Disabilities

The objective of this study was to investigate the internal consistency and the construct validity of the Dutch version of the Supports Intensity Scale (SIS-NL1.0; Buntinx 2006) in individuals with physical disabilities (N = 65). To investigate the construct validity, the relationship between SIS subscales and practical skills (Barthel Index; BI) was calculated. Support was provided for the internal consistency. The SIS subscales (except Behavior) had moderate to high intercorrelations and the SIS was able to discriminate between groups with different number of disabilities. However, weak relationships were found between the BI and four out of eight SIS subscales. For people with physical disabilities, future revisions of the SIS should also take into consideration limitations in practical skills in other support domains

Rater bias and the measurement of support needs

Copyright © 2006 Australasian Society for the Study of Intellectual Disability Inc.Background: The development and use of support need instruments for funding disability services is a relatively recent initiative. Although the use of these measures appears at face value to provide an objective measure of support needs, little is known about their psychometric properties, particularly with respect to rater bias and purpose of assessment. A measure of support that has been developed in Australia to provide estimates of service needs and associated funding is the Service Need Assessment Profile (SNAP). Method: This study investigated whether SNAP scores obtained for different assessment purposes - research and funding - are affected by rater bias, by comparing SNAP to 3 other measures of support from 29 people with intellectual disabilities. Results: We found that SNAP scores completed for funding purposes showed an individual's support needs to be much greater than comparison scores on both SNAP and the 3 other measures obtained for research purposes. Conclusions: Our results suggest that support measures such as SNAP may significantly overestimate support needs when raters know the assessment is being used for funding purposes.Roma Guscia, Julia Harries, Neil Kirby and Ted Nettelbec

Measurement of environmental constructs in disability assessment instruments

The definitive version is available at www.blackwell-synergy.comThe International Classification of Functioning, Disability and Health (ICF) assumes a biopsychosocial basis for disability and provides a framework for understanding how environmental factors contribute to the experience of disability. To determine the utility of prevalent disability assessment instruments, the authors examined the extent to which a range of such instruments addressed the impact of environmental factors on the individual and whether the instruments designed for different disability groups focused differentially on the environment. Items from 20 widely used disability assessment instruments were linked to the five chapters of the ICF environment component using standardized classification rules. Nineteen of the 20 instruments reviewed measured the environment to varying degrees. It was determined that environmental factors from the Natural Environment and Attitudes chapters were not well accommodated by the majority of instruments. Instruments developed for people with intellectual disabilities had the greatest environmental coverage. Only one instrument provided a relatively comprehensive and economical account of environmental barriers. The authors conclude that ICF classification of environmental factors provides a valuable resource for evaluating the environmental content of existing disability-related instruments, and that it may also provide a useful framework for revising instruments in use and for developing future disability assessment instrumentsRoma Guscia, Stuart Ekberg, Julia Harries and Neil Kirb

Construct and criterion validities of the Service Need Assessment Profile (SNAP): A measure of support for people with disabilities

Copyright © 2006 Australiasian Society for the Study of Intellectual Disability Inc.Background: The Service Need Assessment Profile (SNAP) measures individual functional needs in areas of daily living. It produces a support profile, detailing the time allocations for staff support to assist in each area of need. The Supports Intensity Scale (SIS) is a support needs assessment scale designed to provide an objective measure of a person's need for support in medical, behavioural, and life activities. SIS can be used for individualised support planning, clinical judgements regarding support needs, resource allocation and financial planning. The Inventory for Client and Agency Planning (ICAP) assesses adaptive and maladaptive behaviours and gathers additional information to determine type and amount of special assistance that people with disabilities need. Method: This study evaluated the construct and criterion validities of SNAP in relation to the SIS and ICAP, using assessment data from 114 individuals with a range of disabilities and levels of severity. Results: Construct and criterion validities were supported for the SNAP by high correlations with SIS, ICAP, and staff estimates of support needs and by its capacity to discriminate between sub-groups in expected ways. Conclusions: The results provide support for the use of SNAP as a support needs instrumentRoma Guscia, Julia Harries, Neil Kirby, Ted Nettelbeck and John Tapli

Reliability of the Service Need Assessment Profile (SNAP): A measure of support for people with disabilities

Copyright © 2005 Australiasian Society for the Study of Intellectual Disability Inc.Background: Measures for estimating costs associated with the provision of disability services in Australia have not previously been available. Because such instruments are scarce worldwide, decisions about funding services have relied more on historical precedent and less on individual need. Recognising the necessity for an objective measure, Gould (1998) developed the Service Need Assessment Profile (SNAP), a scale for estimating the support needs and associated costs for people with disabilities. Method: This study examined the technical properties of SNAP using assessment data from 318 adults (190 males and 128 females), mean age 43 years, with a range of disability types and levels of severity, residing in supported accommodation around metropolitan Adelaide, South Australia. Results: Results suggest that SNAP's reliability varies across different sub-groups and across domains. Conclusion: Using SNAP assessments as a method for allocating funds/resources across the disability sector should be approached cautiously, bearing in mind the reported limitations.Roma Guscia, Julia Harries, Neil Kirby, Ted Nettelbeck and John Tapli

Support needs and adaptive behaviors

Copyright © 2005 American Association on Mental RetardationWe used a prepublication version of the Supports Intensity Scale (SIS), the Adaptive Behavior Scale–Residential and Community, and the Inventory for Client and Agency Planning to examine the relationship between support needs and adaptive behavior for 80 people with intellectual disabilities. Dimensionality of the SIS Support Needs Scale (Section 1) was examined in reference to the three areas of conceptual, social, and practical skills reported by the American Association on Mental Retardation as comprising the adaptive behavior construct. Factor analysis of the adaptive behavior subscales and SIS Support Need Scale offered support for measurement of a common underlying construct. When considered in terms of the three adaptive behavior skill areas, this construct related predominantly to conceptual skills.Julia Harries, Roma Guscia, Neil Kirby, Ted Nettelbeck, and John Tapli