Montreal Cognitive Assessment (MoCA) Test for Dementia

The Montreal Cognitive Assessment (MoCA) is a test used to detect mild cognitive decline and early signs of dementia. It can help identify people at risk of Alzheimer's disease and screen for conditions like Parkinson's disease, brain tumors, substance abuse, and head trauma.

Introduced in 2005, the MoCA test is an update from the older Mini-Mental State Examination (MMSE) introduced in 1975. It contains 30 questions and takes 10 minutes to complete. While the MOCA test is useful in detecting dementia, it cannot differentiate between the different dementia types.

This article looks at what is involved in a MoCA test, including how it is scored and how the scores are interpreted. It also explains the different conditions the MOCA test can be applied to as well as the advantages and disadvantages of this important screening tool.

Purpose of the MoCA Test

The MoCA test is a simple, in-office tool that can quickly determine if there is any impairment in a person's cognitive function, including their ability to understand, reason, and remember.

The test is used for adults 55 to 85 with early signs of dementia (the progressive loss of intellectual functioning, especially memory and abstract thinking),

If the test indicates that a person has mild cognitive impairment (MCI), additional evaluations may be done to check for suspected causes, like:

• Alzheimer's disease
• Parkinson's disease
• Vascular dementia
• Lewy body dementia
• Frontotemporal lobe dementia
• Huntington's disease
• Brain tumors (both benign and cancerous)
• Brain metastases (the spread of cancer to the brain)

The MoCA test can also check for MCI in people with known conditions such as:

• Traumatic brain injury
• Stroke
  
• Multiple sclerosis
• Schizophrenia

How the MoCA Works

The MoCA test is based on scores with a maximum score of 30. It takes 10 to 12 minutes to complete.

The MoCA test examines seven domains (aspects) of cognitive function with a total of 11 different exercises and tasks:

1. Executive and visuospatial function: You will first be given a picture with numbered dots (1, 2, 3, 4, 5) and lettered dots (A, B, C, D, E) and asked to connect them sequentially, alternating numbers and letters. Next, you will be given a drawing of a three-dimensional cube and asked to make a copy. Finally, you will be asked to draw a dial clock that reads 10 minutes past 11:00. 
2. Naming: You will be shown pictures of three animals and asked what type of animal they are.
3. Attention: You will first be given a series of numbers and asked to repeat them forward or backward. You will then be given a series of letters and asked to pick out the letter "A." Finally, you will be given several numbers and asked to subtract them from 100.
4. Language: You will first be asked to repeat back two different sentences verbatim. You will then be shown a series of capital letters and asked to pick out all of the "As."
5. Abstraction: You will be asked what is in common between two different things (such as an apple and an orange, or a car and an airplane),
6. Delayed recall: You will be given five words and asked to repeat them back after five minutes.
7. Orientation: You will be asked about the date, month, year, day, city, and place you are in. 

MoCA vs. MMSE

The MoCA is similar to an older test called the Mini-Mental State Exam (MMSE). Both tests use a 30-point scale and take only a few minutes to complete. 

Both the MoCA and MMSE have their benefits, limitations, and uses:

• MOCA: This test is better at distinguishing between normal cognition and MCI. The test is harder than the MMSE and less informative in people with moderate to severe dementia as their ability to complete the task rapidly falls away. The MoCA is used primarily for the early detection of dementia.
• MMSE: This test is better for people with known dementia. Because it is less difficult, it can detect subtle changes in cognition even if certain domains are unaffected. (For instance, a highly educated person might still have high executive function but be unable to recall the names of their grandkids.) Because of this, the MMSE is better suited to monitor the decline in cognition.

On their own, neither test can diagnose the cause of cognitive impairment or dementia.

Scoring the MoCA Test

The total score on the MoCA test ranges from 0 to 30. The scoring per domain is broken downs as follows:

Because a person's education can limit their comprehension of certain tasks, 1 point is added to the total score if a person has 12 years or less of formal education. 

Interpreting the Results

After tallying the MoCA scores, the results can be interpreted as follows:

Advantages vs. Disadvantages

Among the advantages of the MoCA test:

• It is simple and brief.
• It has a high sensitivity for mild cognitive impairment.
• It is an objective test that is less vulnerable to subjective interpretation.
• It is available in more than 35 languages as well as versions for people with blindness or hearing impairment.
• Unlike the MMSE, it is not copyrighted and therefore free for non-profit use.

Among the disadvantages of the MoCA test:

• Training is needed for the test to be administered and scored correctly.
• A person’s education level can influence the results. (Poverty can also influence the results as it is linked to lower educational status.)
• Certain mental health problems can skew the results and lead to incorrect findings. People with depression, for example, often score lower without having actual cognitive impairment.
• The test cannot determine which type of dementia is involved.

How Accurate is the MoCA Test?

The MoCA test is generally better at detecting MCI and early dementia than the MMSE test. This is based on comparisons of the sensitivity (the ability to correctly identify people with a disease) and specificity (the ability to correctly identify people without a disease) of both tests.

A 2015 study published in BMC Geriatrics reported that the MoCA has a sensitivity and specificity of 90% and 87%, respectively, in detecting MCI. By contrast, the MMSE has a sensitivity and specificity of 18% and 100%.

MMSE was only better at detecting when someone doesn't have MCI.

Summary

The MoCA test is a simple, in-office test that can detect mild cognitive impairment and the early onset of dementia. It does so based on 11 questions that evaluate seven domains of cognitive function. The MoCA has a maximum score of 30, and anything below 24 is a sign of cognitive impairment.