Screening for offenders with an intellectual disability: the validity of the Learning Disability Screening Questionnaire.
A six-item screener quickly flags offenders who need full IQ testing, though expect a few more misses in forensic settings than in the community.
01Research in Context
What this study did
McKenzie et al. (2012) tested a short six-question form called the LDSQ.
The form is meant to spot offenders who might have an intellectual disability.
Staff gave the form to people in forensic settings and then checked results against full IQ tests.
What they found
The LDSQ caught most cases that later met IQ criteria.
It also kept out most people who did not have low IQ.
Accuracy stayed above 80 %, though the tool missed a few more people in forensic sites than in community sites.
How this fits with other research
Emerson et al. (2023) mapped over 50 coding tools for autism; the LDSQ adds a quick ID screen that could sit beside those longer systems.
Webb et al. (1999) tweaked depression criteria for inpatients with ID; together the papers show that standard checklists need small changes when used with people who have low IQ.
Hostyn et al. (2010) built a scale to watch staff-client talk; like the LDSQ, it gives teams a fast way to measure something that once needed long tests.
Why it matters
If you work in justice or probation settings, keep a stack of LDSQ forms at intake. One minute of questions tells you who needs a full IQ test and who does not. That saves hours and gets supports in place faster.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →Add the LDSQ to your intake packet; anyone who scores in the risk zone moves straight to full IQ testing.
02At a glance
03Original abstract
The study assessed the validity of an intellectual disability screening tool, the Learning Disability Screening Questionnaire (LDSQ), in three forensic settings: a community intellectual disability forensic service; a forensic in-patient secure unit and a prison, using data for 94 individuals. A significant positive relationship was found between full scale IQ and LDSQ score, indicating convergent validity. Discriminative validity was indicated by, firstly, a significant difference in the LDSQ scores between those with and without an intellectual disability, with those with a diagnosis of intellectual disability, scoring significantly lower. Secondly, a ROC analysis indicated that the sensitivity and specificity of the LDSQ were both above 80%. The screening tool was found to have lower sensitivity in the forensic populations than was obtained in the original community standardisation sample, but had slightly higher specificity. Limitations and implications of the study are discussed.
Research in developmental disabilities, 2012 · doi:10.1016/j.ridd.2011.12.006