There is no single test for diagnosing disorders causing dementia. Doctors use several tests and assessments to determine the cause of the person’s symptoms and rule out other possible conditions.

Dementia is a general term for the loss of a range of mental abilities, including memory, language, reasoning, and problem-solving. These changes are gradual and may become severe enough to affect a person’s daily life and relationships.

Doctors diagnose around 10 million new cases of dementia each year. Diagnosing the condition and its type can be challenging because various diseases that destroy the brain can cause it.

However, getting an early diagnosis of dementia is important for a person to receive early treatment and support, allowing them to plan well for the future.

This article explores the different cognitive assessment tests that doctors use to diagnose dementia and other tests.

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Typical age-related memory loss should not be a cause of concern. However, cognitive complaints or memory changes that interfere with a person’s daily function warrant a visit to a healthcare professional.

This may be from a report of the person themselves or a family or loved one, even without the person’s agreement.

The Alzheimer’s Association identifies certain early signs and symptoms that can be a cause of concern, including:

  • forgetting important events and appointments
  • forgetting information that a person once knew well
  • difficulty with once-familiar tasks
  • becoming disoriented with people’s names and in one’s own home or neighborhood
  • forgetting whether a close family member is still alive
  • personality change
  • depression
  • falls or balance problems
  • deterioration of a chronic disease without explanation

Screening may sometimes be a part of an annual wellness visit for Medicare beneficiaries.

Learn more about the early signs and symptoms of dementia here.

Cognitive tests are one of the measures doctors use to assess people with dementia. These tests identify a person who needs further evaluation and if a full dementia evaluation is necessary.

Generally, cognitive tests measure a range of mental abilities such as:

  • awareness of people, time, and place (orientation)
  • short- and long-term memory
  • language and communication skills
  • problem-solving
  • simple math skills
  • visual and spatial skills
  • attention and concentration
  • ability to follow instructions

Some of these tests are brief, while others are more complex and require a separate appointment with a neuropsychologist.

Most involve a series of questions, often verbal and on paper, with corresponding scores.

Mini-Mental State Examination

The Mini-Mental State Examination (MMSE) is the most common screening test for cognitive impairment such as dementia. It consists of 11 questions or tasks grouped under seven “cognitive domains.” A person can complete the test within five minutes.

A person can get a possible score of 30. A healthcare professional bases the score on direct observation of the person completing items or tasks. A doctor can score a person’s level of dementia according to their score:

  • 25–30: no impairment
  • 20–24: mild dementia
  • 13–20: moderate dementia
  • 12 and below: severe dementia

Abbreviated Mental Test Score

The Abbreviated Mental Test Score (AMTS) assesses the possibility of dementia in elderly patients.

It involves a practitioner asking a person with suspected dementia 10 questions, such as their date of birth, address, and who the current president/monarch/head of state is. The person gets a point for each correct answer.

A score of six and below suggests dementia or delirium.

Mini-Cog

This is a brief screening test that a person can do in three minutes. A doctor asks a person to do two tests: Clock drawing and three-word registration and recall.

Clock drawing involves drawing a clockface with all the numbers and a time that the doctor specifies.

Three-word registration and recall is when a person listens to three words from a doctor and repeats them. After the clock-drawing test, they will need to remember and recall these words again.

A person can get a total of 5 points for the test. People with a score of 3–5 have a lower likelihood of dementia, but it does not rule out some degree of cognitive impairment.

General Practitioner assessment of Cognition

The General Practitioner assessment of Cognition (GPCOG) is a sensitive screening tool for cognitive impairment. General practitioners, family doctors, and primary care physicians use it to assess if a person may have dementia. It consists of a patient assessment and an informant interview.

The patient assessment gives a person a score between 0 and 9. A doctor will need more information for those who score 5–8 and would likely ask for an informant interview. A score of 0–4 indicates cognitive impairment.

The informant interview asks a relative, carer, or someone who knows the patient well about their level of impairment. A higher score indicates less impairment, while a score of 0–3 indicates cognitive impairment.

Montreal Cognitive Assessment

The Montreal Cognitive Assessment (MoCA) is a tool that helps healthcare professionals detect mild cognitive impairment and Alzheimer’s disease in people.

A 2021 study found that it is a better measure of cognitive function than the MMSE.

It consists of 30 questions that take 10–12 minutes to accomplish. If a person scores 26 and above, doctors do not consider them to have a cognitive impairment.

In the initial study data, people with mild cognitive impairment had an average score of 22.1, while those with Alzheimer’s disease scored an average of 16.2.

Aside from dementia, the test is also useful in assessing cognitive decline in other conditions, including

Healthcare professionals such as family doctors, geriatric psychiatrists, neurologists, speech-language therapists, and occupational therapists use this tool.

Alzheimer’s Disease Assessment Scale — Cognitive

The Alzheimer’s Disease Assessment Scale — Cognitive (ADAS — Cog) assesses the level of cognitive dysfunction in people with Alzheimer’s disease.

It is more thorough than MMSE and primarily measures language and memory. It has 11 parts and takes around 30 minutes to complete. A doctor or psychologist performs this test in their office.

A diagnosis may offer relief as it “answers” the reason behind a person’s failing memory, behavior changes, and communication difficulties.

Detecting dementia can help a person and their loved ones plan while they are still able to make decisions about their future care, support, and treatment. This also gives them time to arrange legal and financial matters.

Doctors may also recommend lifestyle changes that prevent or slow down the disease. A formal diagnosis also gives a person access to treatments for symptoms, time to build their care team, and the potential to enroll in clinical trials.

An early diagnosis also helps prepare the person’s family. It helps them receive the information, advice, and resources they need to prepare for the challenges as the disease progresses.

Learn more about the stages of dementia here.

No single test can diagnose dementia. There are several other medical tests that healthcare professionals may perform during the diagnostic process. We list these below.

Medical history

A primary care physician will begin their assessment by asking a series of questions about a person’s medical history, including their psychiatric history and the history of their behavioral or cognitive changes.

They will also ask about medical conditions affecting family members and whether the person has relatives with Alzheimer’s disease or dementia.

Common questions include:

  • “What symptoms do you notice?”
  • “When do they occur?”
  • “How often do they happen?”
  • “When did they begin?”

The doctor may also ask family members to provide observations about the person’s behavior and cognitive changes.

Blood tests

A doctor will also arrange for blood tests to help rule out other causes of symptoms, such as hormonal imbalance and vitamin deficiency. These generally include:

They may also run a urinalysis or a cerebrospinal fluid analysis if they suspect an infection. They may also request a toxicology screen involving drug and alcohol tests.

The PrecivityAD blood test looks at specific markers in the blood that relate to Alzheimer’s disease. These markers can identify a person’s likelihood of amyloid plaques in the brain. They include beta-amyloid and apolipoprotein E (APOE).

Neurological exam

A doctor, specifically a neurologist, may perform a neurological exam to check for central nervous system disorders. The tests they perform will vary depending on the person’s symptoms.

Generally, they will evaluate a person’s:

  • level of consciousness or alertness
  • mental status or cognition
  • speech
  • cranial nerve function
  • strength and muscle tone
  • coordination
  • reflexes
  • mobility and gait
  • sensory abilities

Brain imaging

A doctor may sometimes request a brain imaging test to see brain changes and rule out other conditions that may cause the symptoms, including brain tumors, infarcts (tissue death due to loss of blood supply, also known as an ischemic stroke), and hydrocephalus (a buildup of fluid in the brain). Imaging tests include:

  • CT or MRI scan: These check for other brain conditions such as stroke, hemorrhage, and tumors.
  • PET scan: This checks for brain activity patterns and amyloid or tau protein deposits, indicating Alzheimer’s disease.

It is ideal to speak with a doctor when a person is becoming increasingly forgetful or when memory problems are already interfering with their daily function.

Other signs that prompt a visit with a doctor include:

  • difficulty completing familiar tasks
  • confusion with time and place
  • problems finding the words when speaking and problems with following or joining conversations
  • often misplacing things or losing items
  • changes in personality and mood

Different services are available for people with dementia, depending on the level of support they need:

  • Day-to-day support: This is available through respite services and adult day care centers.
  • Long-term care: Carers can provide general or medical care through paid home care services.
  • Residential care: This option can provide longer-term care and supervision through nursing homes, residential care, and retirement communities.
  • Hospice services: These provide end-of-life care. Loved ones may choose for a person with dementia to receive this care in their home, in a hospice facility, or in the hospital.

People can also call the Alzheimer’s Association’s 24/7 helpline on 800-272-3900 for support, resources, and guidance in caring for people with dementia.

Read more about how to care for a person with dementia here.

Disorders causing dementia lead to a gradual loss of mental abilities as brain cells die. Healthcare professionals use cognitive assessments to measure a person’s thinking abilities, such as memory, language, and reasoning.

A cognitive test does not diagnose a person with dementia. Clinicians typically use a combination of tests to accurately diagnose the condition.

Many of these cognitive tests can identify early cognitive impairment, which can help detect the early stages of dementia and people at risk of developing it.