Item and error analysis on Raven's Coloured Progressive Matrices in Williams Syndrome.
RCPM scores give a fair match between Williams Syndrome and typical kids because the error footprints are the same.
01Research in Context
What this study did
The team gave Raven’s Coloured Progressive Matrices to the kids with Williams Syndrome and 24 typical kids.
They matched the groups on raw score, then looked at which items each child got wrong and why.
The goal was to see if WS kids make the same kinds of mistakes as typical kids, just slower.
What they found
Both groups found the same items hard and the same items easy.
They also made the same types of errors in the same places.
The data say WS kids show a delay, not a different pattern.
How this fits with other research
Facon et al. (2010) saw the same item order in Down syndrome, so the test behaves the same across two genetic disorders.
Hopkins et al. (2023) tell a different story: kids with cerebral palsy show odd error types even when total scores match.
Together the papers draw a line—RCPM scores stay fair for WS and Down groups, but you must watch for qualitatively weird errors in CP.
Why it matters
You can safely use Raven’s matrices to match WS participants to controls in your studies or classrooms.
Just check raw score; no extra error coding is needed.
If you ever test a child with CP, run the same error check D et al. did before you trust the score.
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02At a glance
03Original abstract
Raven's Coloured Progressive Matrices (RCPM) is a standardised test that is commonly used to obtain a non-verbal reasoning score for children. As the RCPM involves the matching of a target to a pattern it is also considered to be a visuo-spatial perception task. RCPM is therefore frequently used in studies in Williams Syndrome (WS), in order to match WS participants to a control group or as a single measure to predict performance on a test-condition in developmental trajectory analyses. However, little is known about the performance of participants with WS on the RCPM. The current study compared the type of errors and the difficulty of each item for 53 participants with WS to 53 typically developing children who were individually matched on the total raw score for RCPM. Results showed that the participants with WS made the same proportion of error types and that the proportion of error types changed similarly to those of typically developing controls over development. Furthermore, the differential item difficulty between the two groups was highly similar. It is therefore argued that, although participants with WS are delayed on RCPM, their performance is not atypical which suggests that RCPM performance is supported by typical mechanisms. The RCPM is therefore a useful tool to match WS to control groups or to construct developmental trajectories.
Research in developmental disabilities, 2011 · doi:10.1016/j.ridd.2010.09.005