Trump got a perfect score on a screening test for dementia and Alzheimer's - here's what that means

Kevin Lamarque/Reuters

President Donald Trump

• President Donald Trump's doctor Ronny Jackson said on Tuesday that the Commander in Chief is "fit for duty."
• Jackson said he scored 100% on a 10-minute dementia test.
• The Montreal Cognitive Assessment is a 30-point exam meant to screen for Alzheimer's and other cognitive impairments in older adults. Experts agree it's a good test for dementia.

On Tuesday afternoon, presidential physician Ronny Jackson told reporters at the White House that President Trump should probably lose a few pounds, and that he could probably benefit from cutting some calories from his diet.

But when it comes to the presidential mind, Jackson says he spotted "no issues whatsoever" with Trump's thought process during his first medical exam as a sitting President. Jackson said Trump is "very sharp" and "articulate" and that he got a perfect score on a gold-standard dementia test.

The test that Jackson used during his exam last Friday is called the 'Montreal Cognitive Assessment, or MoCA. Normally, you can view it online here (but on Tuesday afternoon shortly after Jackson's announcement, the website was down.)

The 30-point cognitive exam screens for Alzheimer's, Parkinson's and other dementia in elderly adults. It takes about 10 minutes for a doctor to administer, and is widely regarded as an early and easy way to decide if someone is getting dementia. It's been translated into dozens of languages.

On Tuesday, Jackson said "if he had some type of mental cognitive issue, this test is sensitive enough that it would pick up on it."

A 2005 study in the Journal of the American Geriatrics Society backs up that assertion, saying the test is very sensitive and specific at detecting cognitive impairment.

For anyone without age-related cognitive declines, it's a pretty easy exam. Patients have to name some animals, repeat some phrases, draw a specific time on a clock, and copy a drawing of a cube. Then they're graded on things like short-term memory, visuo-spatial abilities, executive functioning, attention, concentration, and working memory.

The test is meant as a first indication that an elderly person is headed into cognitive decline, and doesn't screen for any non age-related cognitive or mental health issues, like depression, anxiety, bipolar disorder or psychosis.

Here's a sample of what the test from 2009 looks like:

Dementia Services and Information Development Centre