When memory lapses or confusion start showing up in a loved one, it’s natural to wonder if it could be dementia. But how do you know when it’s more than just “normal aging”?
One simple tool doctors often use is the clock test. It may look easy, just drawing a clock, but it can reveal a lot about how the brain is working.
Here’s the key: the clock test isn’t a diagnosis on its own, but it can be an important first step in spotting cognitive changes early.
Quick Rundown: Clock Test for Dementia, What It Reveals
- Simple but Powerful: The test asks someone to draw a clock showing a specific time, revealing cognitive strengths and weaknesses.
- Key Skills Measured: It checks memory, planning, spatial awareness, and executive function.
- Scoring System: Healthcare providers evaluate number placement, clock hands, and recall of unrelated words.
- Not a Diagnosis: A failed test signals possible impairment but requires full clinical evaluation.
- Possible Conditions: Abnormal results may point to Alzheimer’s, vascular dementia, Parkinson’s, or other cognitive disorders.
With that understanding, let’s look closer at how the clock test works, what it can show, and why it’s often used to screen for dementia.
What Is The Clock Test For Dementia?
As we said in the introduction, the clock test for dementia is a simple way to help identify older adults who may need further dementia screening.
There are several forms of the test, any of which can be administered from the comfort of your home when you suspect a friend or a family member is experiencing some cognitive dysfunction.
Again, I would caution you that the test is not a definitive test. There are many different tests that can be used to detect dementia and the clock test is just one of them.
Others include the SLUMS test, Montreal Cognitive Assessment (MoCA) and the Mini-Mental State Examination (MMSE). A dementia diagnosis will only be made after a person has undergone a full clinical assessment.
The digital clock-drawing test specifically measures executive function. Executive function includes things like planning, organization, and flexibility.
These skills often decline in people with dementia. So, if someone fails the clock test, it may be an early sign of the condition.
How does the test work? There are a number of variations of the clock test, but all follow the same basic premise.
The aim is to gauge whether the individual can correctly execute a simple clock drawing task.
If they are unable to complete the drawing correctly, it may be an indication that they are experiencing cognitive decline.
How Do You Administer A Clock-Drawing Test?
To do the test, you will need a piece of paper and a pen or pencil.
The screening test starts with you telling the person who is taking the test that you’re giving them a list of 3 (unrelated) words that you want them to remember.
Have them listen to these words and then repeat them back to you.
Next, ask the person to draw the face of a clock on the piece of paper (a circle with the numbers of the clock in the correct position).
Or you can provide them with a pre-drawn clock face (without the hour and minute hand on them). Simply draw a circle on the paper, and then draw the numbers 1-12 around the edge of the circle.
After this, ask the person to draw clock hands on the drawing to represent a specific time. You’ll want to do so in a way that is both ambiguous and clear at the same time.
For example, you can ask them to draw “half past six” or “ten past four.” This way they will have to employ a little bit of critical thinking to come up with the answer.
Once they have done this, ask the person to recite the time aloud. Follow this by having them repeat the list of three unrelated words you gave them at the beginning of the test.
How Do You Score The Clock Draw Test?
Just as there are several forms of the clock drawing test, there are several scoring systems to determine the test results.
Some are a little convoluted, too! Because the idea is just to find out if the person may need to have more in-depth testing done, the Alzheimer’s Association recommends using a simple method of scoring.
Per the Oregon Health and Science University, to score the results of the Clock Drawing Test for Dementia, you start by counting each word the person remembered correctly (total possible score = 3).
Next, look at three things in their clock face drawings: the clock face, the hands, and the numbers.
- For the clock face, you are looking for whether or not all 12 numbers are included, and whether or not they are in the right place.
- For the hands, you are looking to see if they are drawn in the right place and pointing to the correct numbers / time.
- For the numbers, you are looking to make sure that they are legible and in order. Is the clock drawn in a fairly symmetrical way?
Scores:
- A word recall score of 0 suggests the person should be screened for dementia.
- If there are significant differences in the clock face along with a word recall score of 1 or 2, the person should be screened.
- If there are no (or minor) differences in the clock face and a word score of 1 or 2, dementia screening is not indicated.
- A score of 3 indicates normal cognition and no need for screening.
What Does It Mean If You Fail the Clock Drawing Test?
If you have performed the clock drawing test on a friend or family member, you may become concerned if they draw an abnormal clock or different times than you request.
While this may indicate that your loved one is suffering from dementia or Alzheimer’s, this isn’t always the case. This is because the clock test only tests for cognitive deficits, not a particular disease.
To perform well on the clock test, your loved one must first understand your verbal instructions so they know what you want them to do.
They also must have spatial knowledge, visual memory, and the ability to think abstractly. If they are missing even one of these things, they will be unable to perform well on the clock test.
A failed clock test could also indicate Parkinson’s Disease, Huntington’s Disease, Alzheimer’s disease, vascular dementia, frontotemporal dementia, or dementia with Lewy bodies, depending on which aspects of the clock the individual is able to complete.
This is why you shouldn’t treat the failed clock test as the absolute answer as to whether or not your loved one has dementia.
Instead, you should think of a failed clock test as a sign that your loved one needs some professional help.
Read about how to get a parent officially evaluated for dementia.
How Accurate Is The Clock Test For Dementia?
As mentioned above, the clock drawing test is not the absolute answer whether or not your loved one has dementia or not.
While the clock drawing test is accurate in terms of knowing if there is something wrong, it is important not to treat the test as an actual diagnosis of dementia.
Indeed, there is some conflict about its accuracy between recent studies and previous studies. Some say it’s a great tool, others dispute this – especially where very mild cognitive impairment is concerned.
For example, one study that was published in 2002 in the journal, Neurology, evaluated the accuracy of the clock drawing test in diagnosing dementia.
It concluded that, “Although the clock drawing test can be scored reliably and can differentiate cognitively normal older adults from those with at least mild dementia of the Alzheimer type, it does not appear to be a useful screening instrument for detecting very mild dementia.“
A more recent study by Kim, et al, and published in Dementia And Neurocognitive Disorders in 2018 concluded that, “The results demonstrated that the CDT [clock drawing test] is a useful cognitive screening tool that is comparable with the Mini-Mental State Examination, and that simple CDT scoring systems are sufficient for differentiating patients with MCI [mild cognitive impairment] and mild dementia from CN [cognitively normal adults].“
That said, the Alzheimer’s Association endorses the clock test, again, as one component of a battery of neuropsychological tests for measuring cognitive function.
So if you choose to try the test on a loved one you are concerned about, and they fail it, be sure to make an appointment for them with a doctor.
Let the doctor know about the failed clock test, and they will perform further tests to be able to evaluate the state of your loved one’s mind more in depth. They will then provide a medical diagnosis.
TIP: if your loved one does get a definite dementia diagnosis, there are many scenarios to start planning for.
One of the first things you should do is to set up a power of attorney. You can read more here.
What Is The Standard Test For Dementia (Instead Of The Clock Test)?
The standard test used for dementia over the clock drawing test is something called the MMSE or Mini-Mental State Examination.
This test shouldn’t take too long, and it is one of the most efficient tests for dementia.
This test is almost always performed by a doctor or mental health professional and should not be attempted to be performed at home.
It is the most common screening tool for dementia and assesses numerous skills.
This test is made up of a series of questions that will gauge what information the patient knows about the world around them.
The first set of questions is about the date, time, and location where the patient is taking the test.
Next, the examiner will gauge mental acuity by asking the patient to perform a task. This task is usually to count backwards from a certain number, or to spell a certain word.
The test also evaluates whether or not the patient can remember facts they stated earlier in the test.
Late on, the examiner will begin asking the examinee to read, draw, and follow verbal directions. This helps the doctor to know exactly where the issues are in the patient’s mind.
The results of this test will not only let the examiner know if the individual taking the test has dementia or not, but it will additionally tell them the severity of the dementia, as there are points awarded for each of the tasks.
ADHD and the Clock-Drawing Test
One other factor to consider is if the person has ADHD as this can affect their performance on the Clock Drawing Test (CDT).
ADHD (Attention-Deficit/Hyperactivity Disorder) is characterized by symptoms such as inattention, impulsivity, and hyperactivity, which can change how someone completes tasks that require sustained attention, planning, and organization.
In fact, studies have shown that children with ADHD tend to perform worse on the CDT compared to their peers without ADHD. Specifically:
- Inattention and Executive Dysfunction: The CDT requires attention to detail, planning, and organizational skills—all areas where individuals with ADHD may struggle. For example, errors in placing numbers or setting clock hands could result from difficulties in sustaining attention or managing task complexity.
- Complexity of the Task: Performance tends to decline as the complexity of the CDT increases. For instance, free-drawn clocks (where participants must draw the entire clock from scratch) are more challenging for individuals with ADHD than pre-drawn clocks (where some elements are provided).
- Variability in Performance: While inattentiveness and hyperactivity/impulsivity scores do not consistently correlate with CDT errors, children with ADHD often show poorer performance on tasks requiring sustained effort or higher cognitive load.
Implications for Dementia Screening
Although individuals with ADHD may complete the CDT, their performance might be impacted by their condition rather than by dementia-related cognitive decline. This can complicate the interpretation of results:
- False Positives: Errors made by individuals with ADHD might mimic those seen in dementia (e.g., misplacing numbers or drawing inaccurate clock hands), potentially leading to false-positive results if ADHD is not considered.
- Need for Contextual Evaluation: To accurately interpret CDT results in someone with ADHD, clinicians should consider the individual’s baseline cognitive abilities and account for the impact of ADHD symptoms on test performance.
- Complementary Assessments: Using additional cognitive tests (e.g., Mini-Mental State Examination or other executive function assessments) alongside the CDT can help differentiate between ADHD-related difficulties and dementia.
Final Thoughts
Thinking your loved one may have dementia or Alzheimer’s disease is a scary thing. If you’re worried about them, you can try giving the person the clock test at home to either confirm or ease your worries.
It is critical to remember however, that the clock test is not an official diagnostic test. If your loved one fails the clock test, however, this is a sign that something is wrong and that you should seek medical help.
Once you do, a qualified professional will administer an Mini-Mental State Examination. The MMSE scores will help them determine whether or not your loved one is truly suffering from dementia.
Frequently Asked Questions
What is the difference between brain fog and dementia?
Brain fog and dementia are often confused, but they’re actually quite different! Brain fog is a term used to describe having difficulty concentrating or focusing in the short-term. It can cause someone to feel mentally “foggy” and unfocused. On the other hand, dementia is a chronic condition that affects cognitive functions in the long-term, such as memory loss, reasoning, problem solving, language, and communication abilities. Dementia usually worsens over time and requires professional medical treatment. While brain fog can be an alarming symptom of an underlying medical condition, it should not be mistaken for dementia. If you’re concerned about your mental clarity or thinking ability, speak with your doctor to get an accurate diagnosis.
Is dementia genetic or hereditary?
The answer to whether dementia is genetic or hereditary isn’t simple. While some forms of dementia can run in families, it’s not necessarily a direct result of genetics or heredity. That being said, there are some genes that have been linked to an increased risk for certain types of dementia. For example, mutations in the amyloid precursor protein (APP) and presenilin-1 (PSEN1) genes are associated with early-onset Alzheimer’s disease. The inheritance of these gene mutations is an autosomal dominant pattern which means only one parent needs to pass along the mutation for it to occur in their offspring. So while these particular gene mutations may increase your chances of developing certain types of dementia, it’s important to remember that there is no guarantee. Other types of dementia are caused by a combination of genetic and non-genetic factors such as lifestyle choices, head injuries, medical conditions, or environmental exposures.
