What fraction of inmates with severe mental illness also have drug/alcohol abuse?

• A. 1/2 (50%)
• B. 1/4 (25%)
• C. 2/3 (66%)
• D. 3/4 (72%)

Answer: (D)

This item tests how often substance use issues occur alongside severe mental illness in prison populations. Inmates with severe mental illness frequently also struggle with drug or alcohol abuse, so the best overall estimate is that about three-quarters of them have a co-occurring substance use disorder.

Think of the idea this way: dual diagnosis is very common in this setting, driven by factors like self-medication, ongoing life stressors, and barriers to timely treatment. Because of that high overlap, a fraction around 75% best captures the reality, which is why three-quarters is the correct choice.

The other options underestimate the overlap, making them less representative of the typical comorbidity pattern observed in these populations.