A long-term study of offending in individuals diagnosed with a developmental language disorder as children

Abstract

So far, very few studies have specifically investigated the relationship between language development and offending. To estimate the prevalence and types of offending we compared 469 individuals with developmental language disorders (DLD) (consecutively assessed in the same clinic during a period of 10 years) and 2345 controls from the general population with no known history of language deficits. Each language-disordered child was individually matched with five control children by gender, day of birth, and place of birth (county), but not by mental health and learning disability problems (IQ). All participants were screened through the nationwide Danish Register of Criminality (DRC), covering a mean study period of 22.5 years. Mean age at follow-up was 37.5 years in both groups (range: 29.9 – 48.4 years). The full account of conviction records in the DRC was used as an objective measure of a wide range of offending. No significant difference in total conviction rate was found between the DLD cases and their comparison participants. Altogether, 19.8% of DLD individuals and 23.1% of controls had been convicted (p = 0.13; OR = 0.82; 95% CI: 0.64 – 1.06), but the nature of their offending may be somewhat different. Specific types of offending, with the exception of violations of traffic law and thefts of all kind, occurred with low frequency in both groups. Of particular interest is that 9/329 (2.7%) of males in the DLD group were convicted of sexual offending against 10/1645 (0.6%) in the comparison group (p = 0.002; OR = 4.6; 95% CI: 1.64 – 12.7). However, two of sex offenders were categorized as having a “mild mental retardation” and in the discussion particular attention is given to the possibility that our study overestimated the association between DLD and sexual offending in males.

Keywords:

• Developmental language disorder
• offending
• sex offenders
• case-control study