The mental status examination (MSE) is an evaluation of a patient's cognitive and affective state and begins at the start of the patient encounter. Clinical judgment is the foundation of the MSE because much of the examination depends on the physician's observations and interpretations.¹ Implicit bias, if not appropriately addressed, may alter the results.²

The MSE can be as simple as observing a patient or as comprehensive as using a formal evaluative tool. The examination includes evaluation of several cognitive domains, which have been reviewed in a previous American Family Physician (AFP) article³ and can help the primary care physician identify and distinguish a variety of conditions such as delirium, dementia, mania, or depression.

Most domains can be evaluated in a typical clinic visit through general observation of the patient's appearance, affect, attention, language, and praxis. Assessment of executive function and memory may require a dedicated evaluation.^1,3 Table 1 lists typical components of the MSE.³

Decision to Screen

It is unclear whether an early diagnosis of mild cognitive impairment (MCI) or dementia improves patient outcomes or increases support for the caregiver or use of advanced care planning.⁴ For these reasons, the U.S. Preventive Services Task Force has determined that there is insufficient evidence to recommend screening for cognitive impairment in asymptomatic older adults (I statement).⁴ Furthermore, the 5th Canadian Consensus Conference on the diagnosis and treatment of dementia recommends against routine cognitive screening of asymptomatic individuals.⁵ Therefore, shared decision-making with patients and their caregivers should drive the decision to screen.

However, the U.S. Preventive Services Task Force acknowledges that Medicare requires assessment of cognitive impairment as part of the annual wellness visit due to its increasing prevalence.⁴ The American Academy of Neurology recommends using a validated screening tool to assess for impairment instead of relying on subjective reports of cognition alone.⁶

In routine patient encounters, targeted evaluations should only be performed if concerns arise, such as when the patient cannot recall past events or struggles to follow a line of questioning. In that setting, assessing a specific domain, such as orientation (asking the patient for the date, their name, and current location), could be helpful.¹ If the encounter reveals a general concern for cognitive impairment, brief screening tests, such as the Rapid Cognitive Screen, could be used. Although these tools only evaluate a few domains, they may indicate the need for further testing.^7,8

When there are concerns regarding cognitive function, patients and their caregivers often present first to a primary care physician. It is appropriate to address these concerns by performing a focused history and physical examination to rule out alternate causes of impaired cognition. Physicians should consider dedicating a separate visit for cognitive testing, given the number and complexity of patient factors that can impact performance on the MSE and the validity of screening results, especially when screening for dementia and MCI.¹ These factors can include age, education level, primary language, medications, pain, fatigue, anxiety, and the presence of family members.¹ Expert opinion recommends performing the examination in a nonjudgmental environment without distractions.¹ Although no current guidelines address how to best administer an MSE, Table 2 provides considerations for in-office testing.¹

There are several cognitive screening tools validated for dementia and MCI assessment. In general, these tests are more sensitive for detecting dementia than MCI.⁴ The choice of screening tool is typically based on the clinical scenario and the physician's familiarity with the tests.¹ A positive screening result alone is not sufficient for diagnosis. However, more comprehensive cognitive tests, such as the Mini-Mental State Examination (MMSE), can help diagnose dementia once alternative diagnoses have been ruled out.^5,9 Table 3 lists common screening tools for diagnosing dementia.^{3,4,7,8,10–12}

Although related to the MSE, neuropsychiatric testing that provides detailed assessments of cognitive and emotional functioning is beyond the scope of this article. A previous AFP article discusses how neuropsychiatric testing can be used to determine the severity of cognitive impairment, to guide individualized rehabilitation, or when diagnosis is unclear.¹³

Cognitive Screening Tools

MINI-MENTAL STATE EXAMINATION

The MMSE is one of the most well-known assessments of mental status. It was developed in 1975 and is the most researched cognitive screening tool available. Advantages of the MMSE include its ability to differentiate moderate dementia from normal cognition and its assessment of multiple cognitive domains, including attention, language, memory, orientation, and visuospatial proficiency.^5,9 It is available in multiple languages, including English, Spanish, and Chinese.¹⁴

The primary disadvantage of the MMSE is its inability to detect MCI that will progress to dementia. A 2021 Cochrane review found the sensitivity and specificity for detecting MCI that will progress to dementia to be 23% to 76% and 40% to 94%, respectively, when administered as a stand-alone baseline test.¹⁵ Therefore, the MMSE should not be used to screen for MCI in the primary care setting.

Additionally, interpretation requires consideration of age, education, and cultural background for scoring. If these components are not appropriately incorporated, the scoring is invalid.¹⁶ Another notable deterrent to using the MMSE is its proprietary nature. The manual and questionnaires must be purchased to use.¹⁴ The product website offers free training, which is recommended but not required, before use of the examination.¹⁴

MONTREAL COGNITIVE ASSESSMENT

The Montreal Cognitive Assessment (MoCA) is a nonproprietary screening tool that assesses all the domains of the MMSE with additional emphasis on executive function and verbal fluency. A Cochrane review found the MoCA to be highly accurate for detecting dementia, but none of the studies included in the review were done in the primary care setting.¹⁰

For identification of MCI, the MoCA is superior to the MMSE, but is not as effective as the Addenbrooke's Cognitive Examination (ACE)-Revised.^17–19

The manufacturer of the MoCA requires one hour of training, free on their website, before certifying an examiner to perform the test.²⁰ A mobile application allows the test to be administered via tablet, with several subscription options available; up to 20 tests per month can be administered for free.²¹

The MoCA does have drawbacks. A test is considered positive when the score is less than 26 out of 30, but this has been associated with false-positive rates as high as 40%.¹⁰ A positive screening result can lead to a misdiagnosis of MCI because this diagnosis is often inappropriately made by testing alone. Proposals to lower the score cutoff or adjust the components of the test to better account for education may help with this issue, but they require more research.^22,23

Despite its publication in more than 100 languages and dialects, the MoCA has shown varying sensitivity and specificity across cultures and may require score adjustments when administered in different languages.^24,25

SAINT LOUIS UNIVERSITY MENTAL STATUS EXAMINATION

The Saint Louis University Mental Status (SLUMS) Examination is a nonproprietary cognitive assessment similar to the MoCA. The original validation study has shown the SLUMS examination to be highly sensitive, but its sensitivity and specificity for both MCI and dementia vary depending on the patient's level of education.¹¹

Advantages of the SLUMS Examination include assessment of multiple domains such as attention, memory, orientation, and executive function. It is available in multiple languages, including English, Spanish, Arabic, and Chinese.²⁶ The test is free and requires no formal training to administer. A recent study found similar validity between the SLUMS Examination and the MoCA, but found the MoCA takes twice as long to administer.²⁷

The primary disadvantage to the SLUMS Examination is that it has been studied mainly in a White, male population, but more research is being conducted to determine whether it has similar accuracy in diverse populations.^28–32

ADDENBROOKE'S COGNITIVE EXAMINATION

The ACE is another multidomain assessment and has been updated several times since its original publication. Previous studies supported use of the ACE-Revised, the second edition of the test, for cognitive impairment screening. However, a 2019 Cochrane review found insufficient evidence to support use of the most recent versions, such as the ACE-III and its abbreviated form, the Mini-ACE.¹² Both have variable sensitivities across diverse populations and lack research in the primary care setting.¹² Additionally, the ACE-III is longer than the MoCA, which may make it more difficult to administer in a busy clinic.¹⁶ The ACE-III and Mini-ACE should not be used to screen for cognitive impairment if alternative tests are available.

RAPID COGNITIVE SCREEN

The Rapid Cognitive Screen is a three-item assessment adapted from the SLUMS Examination. It takes less than three minutes to perform and comprises recall and insight questions and a clock drawing test. It has demonstrated high overall accuracy compared with the SLUMS Examination, with an area under the curve (AUC) of 0.97 (95% CI, 0.94 to 0.99) for dementia and an AUC of 0.79 (95% CI, 0.69 to 0.88) for MCI.⁷ An AUC of 1.0 represents a perfectly accurate test, and an AUC of 0.5 or less indicates a useless test.³³ A meta-analysis found that the overall accuracy of the Rapid Cognitive Screen is high compared with the MoCA for both dementia and MCI in a multiethnic population (AUC = 0.82; 95% CI, 0.75 to 0.90).³⁴ Given its speed and relative accuracy, the Rapid Cognitive Screen may be the best brief screening tool for dementia and MCI available to busy physicians. But, like the SLUMS Examination, further studies are needed to ensure its applicability among a diverse patient population.

MINI-COG

The Mini-Cog is a brief cognitive screen that consists of three-word delayed recall and a clock drawing test.⁸ It has been the subject of several Cochrane reviews, all of which conclude that the evidence is insufficient to recommend for or against its use for dementia screening.^8,35,36 The greater amount of supporting evidence for and wider range of domains assessed by other short cognitive screening tools may outweigh the time benefit the Mini-Cog provides for most primary care physicians.^34–36

Telemedicine Considerations

Telemedicine visits performed via telephone or video can be as effective as face-to-face visits for many conditions seen in primary care, with high patient satisfaction.³⁷ The MMSE and the MoCA have versions adapted for delivery over the telephone.^38,39 A 2021 Cochrane review found that only low-quality evidence suggests that telemedicine evaluation can be highly accurate for the detection of dementia compared with face-to-face evaluation.⁴⁰ Several subsequent studies have considered this topic, with mixed results. Two meta-analyses found the MMSE to be highly accurate when delivered via a telemedicine visit, with an AUC of 0.95 (95% CI, 0.94 to 0.98).^38,41 Low-quality studies showed mixed results regarding the accuracy of video-based MoCA testing, whereas the telephone-administered MoCA showed a reliable AUC of 0.82 (95% CI, 0.71 to 0.94) when studied in a poststroke population.^38,41,42

Screening tests can be offered to those who prefer telemedicine evaluation. Visual or hearing impairment and difficulties with language or speech can impact telemedicine assessment, and caution should be taken in these cases.⁴¹ Any concern for cognitive impairment, despite negative screening results, warrants in-person follow-up or referral for formal neuropsychiatric testing. There is not enough evidence to support the use of widespread telemedicine screening.

Next Steps

The MSE should incorporate the complete clinical picture, including the patient's history and physical examination, to guide the differential diagnosis and next steps in management. Abnormal responses to one or more components of the MSE can highlight concerns for focal or global impairment.¹ For example, an acute change in mental status with behavioral changes or an altered level of consciousness would point toward a diagnosis of delirium, whereas a history of impaired gnosia or praxis would point toward a diagnosis of stroke.

Reversible causes of cognitive impairment should be explored. This includes screening for comorbid conditions such as depression or a substance use disorder. Medications should be reviewed to identify those that may contribute to impairment, such as anticholinergics or pain medications.⁴³ Evaluation may also include laboratory testing to rule out reversible causes of mental status changes such as hypo- or hyperglycemia, electrolyte abnormalities, acute kidney or liver failure, hypo- or hyperthyroidism, intoxication, low vitamin B₁₂ level, urinary tract infection, or HIV infection.^1,3,43 Neuroimaging with computed tomography, magnetic resonance imaging, or positron emission tomography may be indicated, depending on the clinical scenario.^44,45 Evaluation for altered mental status and suspected dementia were reviewed in previous AFP articles.^43,46 If the diagnosis is still unclear, referral for neuropsychiatric testing or neurologic evaluation may be indicated. Additional information on cognitive impairment can be found at https://www.aafp.org/family-physician/patient-care/care-resources/cognitive-care.html.

This article updates previous articles on this topic by Norris, et al.³ and Snyderman and Rovner.⁴⁷

Data Sources: A PubMed search was completed using the key terms mental status examination, cognitive testing, the Mini-Mental Status Exam, the Montreal Cognitive Assessment, the St. Louis University Mental Status Exam, the Mini-Cog, the Rapid Cognitive Screen, and Addenbrooke’s Cognitive Examination. Additionally, MeSH terms with mental status and dementia tests and primary health care or physicians, primary care were searched. The search included meta-analyses, randomized controlled trials, clinical trials, and reviews. The Cochrane database and Essential Evidence Plus were also searched. Whenever possible, if studies used race, ethnicity, and/or gender as patient catcategories but did not define how these categories were assigned, they were not included in our final review. If studies that used these categories were determined to be essential and therefore included, limitations were explicitly stated in the manuscript. Search dates: February 15 to October 27, 2023.

The opinions and assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the U.S. Air Force, the U.S. Department of Defense, or the U.S. government.