Exploring the impact of disability on self-determination measurement.
The Spanish Self-Determination Inventory is a fair ruler for teens with and without disabilities, so low scores point to real skill gaps, not test bias.
01Research in Context
What this study did
Mumbardó-Adam et al. (2018) checked if the Spanish Self-Determination Inventory works the same for youth with and without disabilities. They looked at each of the 45 items to see if any favored one group over the other.
The sample mixed teens with and without disabilities. The team ran a DIF analysis, a stats test that flags unfair questions.
What they found
Only 5 out of 45 items showed bias. That means 40 items measure self-determination fairly across disability status.
The scale keeps its meaning whether the teen has a disability or not, so you can trust the scores for both groups.
How this fits with other research
Anonymous (2019) later repeated the idea with teens in two countries. They also found the same Spanish scale stays fair, but added that students with intellectual disability still score lower. The 2018 and 2019 papers fit together: the tool is unbiased, yet real skill gaps remain.
Efstratopoulou et al. (2012) looked like they disagreed at first. They saw much lower self-determination scores for students with special needs. The difference is method: Maria used an older scale and compared average scores, while Cristina checked each item for bias. The older study shows the gap; the newer one proves the gap is not the test’s fault.
Dudley et al. (2019) found the opposite pattern with another Spanish scale. Their scale unfairly undervalued adults with severe ID. Cristina’s youth tool avoids that pitfall, giving hope that better item writing can remove bias.
Why it matters
You can now give the Spanish Self-Determination Inventory to any high-schooler, disability or not, and be sure the score reflects real skills—not test bias. Use it during transition planning to set fair, data-based goals. If scores are low, target teaching self-advocacy or choice-making instead of blaming the test.
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02At a glance
03Original abstract
BACKGROUND: Self-determination is a psychological construct that applies to both the general population and to individuals with disabilities that can be self-determined with adequate accommodations and opportunities. As the relevance of self-determination-related skills in life has been recently acknowledged, researchers have created a measure to assess self-determination in adolescents and young adults with and without disabilities. The Self-Determination Inventory: Student Report (Spanish interim version) is empirically being validated into Spanish. AIMS: As this scale is the first assessment addressed to all youth, further exploration of its psychometric properties is required to ensure the reliability of the self-determination measurement and gain further insight into the construct when applied to youth with and without disabilities. METHODS: More than 600 participants were asked to complete the scale. The impact of disability on the item response distributions across the dimensions of self-determination was explored. OUTCOMES: Differential item functioning (DIF) was found in only 5 of the scale's 45 items. Differences primary favored youth without disabilities. CONCLUSIONS: The weak presence of DIF across the items supports the instrument's psychometrical robustness when measuring self-determination in youth with and without disabilities and provides further understanding of the self-determination construct. Implications and future research directions are also discussed.
Research in developmental disabilities, 2018 · doi:10.1016/j.ridd.2018.04.022