Relationship between ADHD symptoms and anti-social behaviour in a sample of older youths in adult Scottish prisons

• The prevalence of ADHD in older youths in adult Scottish prisons was found to be 7%.
• No statistical difference in criminal convictions behaviour between groups.
• Relationship between ADHD and antisocial behaviour in custody unclear.

Individuals with ADHD are more likely to commit crimes, be arrested, receive a prison sentence, and continue to undertake anti-social behaviour while in prison. This study explored the prevalence of ADHD symptoms using the DSM-IV checklist of symptoms and the Conners’ Adult ADHD Rating Scale, and their relationship with criminal convictions and breaches of prison discipline in 168 youth (21–29 years) males within three adult prisons in Scotland. The prevalence of ADHD was found to be 7%, which is consistent with previous research, and higher than that found in the general population. However, no statistical differences were found in the number of criminal convictions among those categorised as “symptomatic” or “at-risk” compared to those categorised as “non-symptomatic” or “no-risk”. The relationship between ADHD symptoms and breaches of prison discipline was dependent on the assessment tool used and therefore remains unclear. While the findings raise questions about the causal relationship proposed in the literature between ADHD and criminal behaviour, the study raises a number of methodological issues that need to be considered in future research. Nonetheless, the higher prevalence of ADHD symptoms in this sample compared to the general population has implications for risk management and rehabilitation that require further exploration.