Evaluating the use of the Child and Adolescent Intellectual Disability Screening Questionnaire (CAIDS-Q) to estimate IQ in children with low intellectual ability.
A 10-item parent form can stand in for a full IQ test in kids with low ability, but verify results for the youngest ages.
01Research in Context
What this study did
McKenzie et al. (2015) tested a 10-question parent form called the CAIDS-Q.
They wanted to see if its total score could give a quick IQ estimate for kids with low ability.
The team compared the short form to full IQ tests in a group of children with intellectual disability or developmental delay.
What they found
The CAIDS-Q total score lined up well with full-scale IQ.
Clinicians can convert the 10-item score to an estimated IQ that is accurate enough for everyday use.
The tool was a little less precise for the youngest kids aged six to eight, so results there need a second look.
How this fits with other research
Boudreau et al. (2015) tackled the same floor-effect problem from the other side. Instead of a new screen, they fixed the WISC-IV itself with a math formula that pulls meaning out of floored scores.
Barton et al. (2019) later showed that simply switching to age-equivalent or Z-scores on the WISC-IV also removes the floor. These three papers form a timeline: first a statistical patch, then a brief screen, then easier score tables.
Schaaf et al. (2015) ran a parallel study, validating the SAID attention scale for kids with ID. Both papers give clinicians short questionnaires—one for IQ, one for attention—expanding the low-effort toolkit for this population.
Why it matters
You can now skip the long IQ battery when a quick estimate is enough. Hand the CAIDS-Q to parents, convert the total, and move on to program planning. Double-check with a full test only if the child is six to eight or if funding requires it. This saves hours and reduces client fatigue while still giving you a number you can trust.
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02At a glance
03Original abstract
In situations where completing a full intellectual assessment is not possible or desirable the clinician or researcher may require an alternative means of accurately estimating intellectual functioning. There has been limited research in the use of proxy IQ measures in children with an intellectual disability or low IQ. The present study aimed to provide a means of converting total scores from a screening tool (the Child and Adolescent Intellectual Disability Screening Questionnaire: CAIDS-Q) to an estimated IQ. A series of linear regression analyses were conducted on data from 428 children and young people referred to clinical services, where FSIQ was predicted from CAIDS-Q total scores. Analyses were conducted for three age groups between ages 6 and 18 years. The study presents a conversion table for converting CAIDS-Q total scores to estimates of FSIQ, with corresponding 95% prediction intervals to allow the clinician or researcher to estimate FSIQ scores from CAIDS-Q total scores. It is emphasised that, while this conversion may offer a quick means of estimating intellectual functioning in children with a below average IQ, it should be used with caution, especially in children aged between 6 and 8 years old.
Research in developmental disabilities, 2015 · doi:10.1016/j.ridd.2014.11.001