Reliability and Validity of the Supports Intensity Scale (SIS) Measured in Adults with Physical Disabilities.
The Dutch SIS is internally reliable for adults with physical disabilities, yet its scores don’t align well with everyday practical skills.
01Research in Context
What this study did
The team tested the Dutch Supports Intensity Scale (SIS-NL1.0) on the adults with physical disabilities. They checked if the scale gave steady scores and if it truly measured support needs.
What they found
The scale hung together well inside (alpha = 0.90). Yet its scores only weakly matched real-life skills like cooking or banking.
How this fits with other research
Johnson et al. (2009) saw strong links between SIS scores and expert rankings in adults with ID. Rispoli et al. (2011) now shows those links break down when the same scale is used with adults who have physical, not intellectual, disabilities.
Chou et al. (2013) later found the SIS useful for funding decisions in Taiwan, but only after testing it on adults with ID. The tool seems to work best when the main barrier is cognitive, not physical.
Verdugo et al. (2010) already proved the Spanish SIS reliable for ID. The Dutch study widens the lens, warning that physical disability alone may need a different lens.
Why it matters
If you serve adults with CP, MS, or spinal injury, the SIS gives a stable snapshot of support needs. Do not trust it to predict how well they can cook, pay bills, or use the bus. Pair it with direct skill probes before you write goals or ask for hours.
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02At a glance
03Original abstract
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.
Journal of developmental and physical disabilities, 2011 · doi:10.1352/0047-6765(2002)040<0390:ISIAAP>2.0.CO;2