According to the neurodevelopmental case study, Mr. A, a twenty-five-year-old Caucasian adult, has a moderate intellectual disability. Using the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), there are three criteria necessary to diagnose intellectual developmental disorder (p. 37). The American Psychiatric Association (2013) states that the specifiers include deficits to intellectual functions and adaptive functioning, as well as, recognition that the intellectual