7.2.1 General considerations
In assessing the impact of mental illness on the ability to drive safely, the focus should be on assessing the severity and significance of likely functional effects, rather than the simple diagnosis of a mental illness. Information relevant to the assessment may be gained from case workers and others involved in the ongoing management of the person. The review period should be tailored to the likely prognosis or pattern of progression of the condition in an individual. Commercial vehicle licences warrant greater concern and a lower threshold for intervention.
Mild mental illness does not usually have a significant impact on functioning. Moderate levels of mental illness commonly affect functioning, but many people will be able to manage usual activities, often with some modification. Severe mental illness often impairs multiple domains of functioning, and it is this category that is most likely to impact on the functions and abilities required for safe driving. A person’s medication requirements should not be used as the only measure of disease severity.