Problem solving ability in children with intellectual disability as measured by the Raven's colored progressive matrices.

The team gave Raven’s Coloured Progressive Matrices to children with intellectual disability. They also tested typically developing kids matched on non-verbal mental age.

They looked at total scores and the kinds of mistakes each group made.

Both groups could earn the same overall score, showing the test can equalize non-verbal mental age.

Children with ID still made more ‘position’ errors, picking answers next to the right one even when their total score matched.

Ballester-Plané et al. (2016) extends this idea to adults with cerebral palsy. They found RCPM also picks up both visual and verbal skills and links to real brain scans.

Bae et al. (2015) seems to disagree. They showed big math word-problem gaps between kids with ASD and matched TD peers. The difference: Nahal studied non-verbal reasoning while Seh studied language-heavy math. The ‘contradiction’ is about the task, not the kids.

Nader-Grosbois et al. (2012) came first with ID problem-solving. They saw more parent help led to worse performance, hinting that immature strategies in Nahal’s study might link to less self-regulation.

You can use RCPM to set mental-age baselines for kids with ID, autism, or Down syndrome. Watch error types, not just totals: lots of positional slips signal a need to teach scanning and self-checking skills before moving to harder visual tasks.