On Monday, the American Academy of Neurology released new guidelines to help family members conclude when it is appropriate to take driving privileges away from relatives who are suffering from Alzheimer’s disease or other forms of dementia.

While admitting that no one source of information is capable of determining when a senior citizen should stop driving, lead guideline author Donald Iverson and his colleagues found that a specific dementia test and the input of family members are the two best ways of making an informed decision.

After scrutinizing more than 400 studies, the investigators determined that families should identify relatives as unsafe to drive by utilizing the Clinical Dementia Rating (CDR) scale, which can be accessed through any personal care physician.

They also stressed that family members should trust their instincts and not rely on driving tests. One study that the team examined found that as many as 76 percent of people with dementia can still pass driving tests, even though they are at a elevated risk of getting into an accident, according to Health Day News.

“As a doctor, I absolutely have to rely on the family’s observations,” said David Knopman, a professor of neurology at the Mayo Clinic.”The brain supports the capacity for insight into your own actions or capabilities. That is critically eroded in patients with Alzheimer’s.”