Neuropsychological and Psychological Testing

Number: 0158

Table Of Contents

Policy
Applicable CPT / HCPCS / ICD-10 Codes
Background
References

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Policy

Scope of Policy

This Clinical Policy Bulletin addresses neuropsychological and psychological testing.

1. Medical Necessity

   Aetna considers the following neuropsychological and psychological testing medically necessary (unless otherwise stated) when criteria are met:

   1. Neuropsychological testing (NPT) when provided to aid in the assessment of cognitive impairment due to medical or psychiatric conditions, when all of the following criteria are met:
      
      
      1. The number of hours or units requested for testing does not exceed the reasonable time necessary to address the clinical questions with the identified measures; and
      2. The testing techniques are validated for the proposed diagnostic question or treatment plan; and
      3. The testing techniques do not represent redundant measurements of the same cognitive, behavioral or emotional domain; and
      4. The testing techniques submitted are both validated for the age and population of the member; and they are the most updated version of the instrument; and
      5. The instruments selected have the empirically substantiated reliability, validity, standardized administration and clinically relevant normative data to assess the diagnostic question or treatment planning goals.

      Examples of medically necessary indications for NPT testing include, but are not limited to:

      1. Assessment of neurocognitive abilities following traumatic brain injury, stroke, or neurosurgery or relating to a medical diagnosis, such as epilepsy, hydrocephalus or AIDS;
      2. Assessment of neurocognitive functions to assist in the development of rehabilitation and/or management strategies for persons with diagnosed neurological disorders;
      3. Differential diagnosis between psychogenic and neurogenic syndromes;
      4. Monitoring of the progression of cognitive impairment secondary to neurological disorders.
   2. NPT or psychological testing (PT) when needed to enhance psychiatric or psychotherapeutic treatment outcomes after a detailed diagnostic evaluation when:
      
      
      1. Testing is needed to aid in the differential diagnosis of behavioral or psychiatric conditions when the member's history and symptomatology are not readily attributable to a particular psychiatric diagnosis and the questions to be answered by testing could not be resolved by a psychiatric/diagnostic interview, observation in therapy, or an assessment for level of care at a mental health or substance abuse facility; or
      2. Testing is needed to develop treatment recommendations after the member has been tried on various medications and/or psychotherapy, has not progressed in treatment, and continues to be symptomatic; and

      All of the following criteria are met:

      1. The number of hours or units requested for testing does not exceed the reasonable time necessary to address the clinical questions with the identified measures; and
      2. The testing techniques are validated for the proposed diagnostic question or treatment plan; and 
      3. The testing techniques do not represent redundant measurements of the same cognitive, behavioral or emotional domain; and
      4. The testing techniques are both validated for the age and population of the member; and they are the most updated version of the instrument; and
      5. The instruments selected have the empirically substantiated reliability, validity, standardized administration and clinically relevant normative data to assess the diagnostic question or treatment planning goals.

      NPT and PT generally are not considered medically necessary for pre-surgical clearance. An evaluation by a psychologist or psychiatrist is sometimes required (for an example, see CPB 0157 - Obesity Surgery).

   3. NPT to distinguish attention deficit/hyperactivity disorder (ADHD) from learning disabilities or language/communication disorders when such distinction remains unclear after history and examination. NPT may be considered medically necessary for neurologically complicated cases of ADHD, (e.g., post head trauma, seizures). NPT or PT is rarely considered medically necessary for uncomplicated cases of attention deficit disorder with/without hyperactivity (ADHD). However, referral to an outpatient mental health provider or outpatient chemical dependency rehabilitation may be considered medically necessary for the evaluation and comprehensive bio-psychosocial treatment for these disorders in collaboration with primary care physicians and other specialists.  
   4. NPT or PT involving standardized parent interviews and direct, structured behavioral observation for the diagnosis of pervasive developmental disorders (see CPB 0648 - Autism Spectrum Disorders).
   5. NPT is considered not medically necessary for diagnosis and management of persons with chronic fatigue syndrome, and evaluation of migraineurs. (Note: PT may be medically necessary to differentiate chronic fatigue syndrome from psychiatric diagnoses when criteria for PT are met.)
   6. NPT or PT is considered not medically necessary if the member is actively abusing substances, is having acute withdrawal symptoms, or has recently entered recovery, because test results may be invalid.
   7. Diagnostic assessment for neurodiversity is considered not medically necessary because of a lack of evidence regarding the clinical value of neurodiversity tests.

2. Experimental and Investigational

   Aetna considers the use of computerized neuropsychological assessment devices (e.g., Cognitrax) experimental and investigational for screening asymptomatic / healthy individuals, and for other indications (e.g., screening and monitoring multiple sclerosis-related cognitive impairment; not an all-inclusive list) because the effectiveness of this approach has not been established.

3. Policy Limitations and Exclusions

   1. NPT requested for the evaluation of a mental health diagnosis (e.g., serious psychiatric illness, alcohol and/or drug abuse) is considered for coverage through the mental health benefit. If NPT or PT is requested for evaluation of a medical diagnosis (e.g., traumatic brain injury, stroke, differentiation of brain damage from a depressive disorder, epilepsy, hydrocephalus, Alzheimer's disease, Parkinson disease, multiple sclerosis, or AIDS), it is considered for coverage under the medical benefit.
   2. NPT may also be used in evaluating the impact of chronic solvent or heavy metal exposure particularly in the occupational or environmental medicine realm. In these cases, NPT would not be covered under Aetna's medical or mental health benefits, but may be covered by the worker's compensation carrier.
   3. NPT or PT for educational reasons is not covered. This testing is usually provided by school systems under applicable state and federal rules. Most benefit plans exclude coverage of educational testing. Please check benefit plan descriptions. In addition, NPT or PT performed for educational reasons is not considered treatment of disease.
   4. NPT or PT for employment, disability qualification, or legal/court-related purposes is not covered as it is not considered treatment of disease.

4. Related Policies

   • CPB 0157 - Obesity Surgery
   • CPB 0648 - Autism Spectrum Disorders

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Table:

CPT Codes / HCPCS Codes / ICD-10 Codes

Code	Code Description
Information in the [brackets] below has been added for clarification purposes.   Codes requiring a 7th character are represented by "+":
CPT codes covered if selection criteria are met:
96116	Neurobehavioral status exam (clinical assessment of thinking, reasoning and judgment, eg, acquired knowledge, attention, language, memory, planning and problem solving, and visual spatial abilities), per hour of the psychologist's or physician's time, both face-to-face time with the patient and time interpreting test results and preparing the report
96121	Neurobehavioral status examination (clinical assessment of thinking, reasoning and judgment, [eg, acquired knowledge, attention, language, memory, planning and problem solving, and visual spatial abilities]), by physician or other qualified health care professional, both face-to-face time with the patient and time interpreting test results and preparing the report; each additional hour (List separately in addition to code for primary procedure)
96125	Standardized cognitive performance testing (eg, Ross Information Processing Assessment) per hour of a qualified health care professional's time, both face-to-face time administering tests to the patient and time interpreting these test results and preparing the report
96130 - 96131	Psychological testing evaluation services by physician or other qualified health care professional, including integration of patient data, interpretation of standardized test results and clinical data, clinical decision making, treatment planning and report, and interactive feedback to the patient, family member(s) or caregiver(s), when performed
96132 - 96133	Neuropsychological testing evaluation services by physician or other qualified health care professional, including integration of patient data, interpretation of standardized test results and clinical data, clinical decision making, treatment planning and report, and interactive feedback to the patient, family member(s) or caregiver(s), when performed
96136 - 96137	Psychological or neuropsychological test administration and scoring by physician or other qualified health care professional, two or more tests, any method
96138 - 96139	Psychological or neuropsychological test administration and scoring by technician, two or more tests, any method
96146	Psychological or neuropsychological test administration, with single automated, standardized instrument via electronic platform, with automated result only
ICD-10 codes covered if selection criteria are met:
E75.00 - E75.09	GM2 gangliosidosis
E75.10 - E75.19	Other and unspecified gangliosidosis
E75.23	Krabbe disease
E75.25	Metachromatic leukodystrophy
E75.29	Other sphingolipidosis
E75.4	Neuronal ceroid lipofuscinosis
F01.50 - F01.C4	Vascular dementia
F03.90 - F03.C4	Unspecified dementia
F07.0	Personality change due to known physiological condition
F07.89	Other personality and behavioral disorders due to known physiological condition
F80.0 - F80.89	Pervasive and specific developmental disorders
F81.0 - F81.9	Developmental disorders [learning disabilities]
F84.2	Rett's syndrome
F90.0 - F90.9	Attention-deficit hyperactivity disorder
G30.0 - G30.9	Alzheimer's disease
G31.01 - G31.9	Other degenerative diseases of nervous system, not elsewhere classified
G91.0 - G91.9	Hydrocephalus
G93.7	Reye's syndrome
I69.00 - I69.019, I69.110 - I69.119, I69.211 - I69.219, I69.311 - I69.319, I69.811 - I69.819, I69.911 - I69.919	Cognitive deficits following cerebrovascular disease
R41.4	Neurologic neglect syndrome
R41.82	Altered mental status, unspecified
S00.00xA - S09.93xS	Injuries to head
ICD-10 codes not covered for indications listed in the CPB:
F10.10 - F19.99	Mental and behavioral disorders due to psychoactive substance use[active abuse, having withdrawal symptoms, or recently entering recovery]
G43.001 - G43.919	Migraine
R53.82	Chronic fatigue, unspecified
Z01.812	Encounter for preprocedural laboratory examination
Z01.818	Encounter for other preprocedural examination
Z13.40 - Z13.49	Encounter for screening for certain developmental disorders in childhood [when billed alone indicates no signs or symptoms]
Z13.850	Encounter for screening for traumatic brain injury [when billed alone indicates no signs or symptoms]
Z13.858	Encounter for screening for other nervous system disorders [when billed alone indicates no signs or symptoms]
Z13.89	Encounter for screening for other disorder [mental disorder screening] [when billed alone indicates no signs or symptoms]
Computerized neuropsychological assessment devices:
CPT codes not covered for indication listed in the CPB:
Computerized neuropsychological assessment devices – no specific code
ICD-10 codes not covered for indications listed in the CPB:
G31.84	Mild cognitive impairment, so stated
G35	Multiple sclerosis [multiple sclerosis-related cognitive impairment]

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Background

Psychological tests assess a range of mental abilities and attributes, including achievement and ability, personality, and neurological functioning.  Psychological testing, including neuropsychological assessment, utilizes a set of standardized tests, whose validity and reliability have been established empirically.  They allow for an assessment of a patient's cognitive and behavioral functioning and an analysis of changes related to mental or physical disease, injury, or abnormal development of the brain.  Research has shown that the scores from these tests are reproducible and can be compared to those of normal persons of similar age, sex and demographic background to yield valid conclusions.

Psychological and neuropsychological tests provide a standardized means of sampling behavior, an objective method for evaluating responses, and a tool for comparing the functioning of an individual with peers.  Standardized tests are administered under uniform conditions, scored objectively – the procedures for scoring the test are specified in detail – and designed to measure relative performance.  Test results usually are interpreted with reference to a comparable group of people, the standardization, or normative sample.

Psychological testing requires a clinically-trained examiner.  All psychological tests should be administered, scored, and interpreted by a qualified professional, such as a licensed psychologist or psychiatrist, with expertise in the appropriate area.

Psychological tests are only one element of a psychological assessment.  They should never be used as the sole basis for a diagnosis.  A detailed clinical interview, including a complete history of the test subject and a review of psychological, medical, educational, and other relevant records is required to lay the groundwork for interpreting the results of any psychological measurement.

Psychological tests are used to address a variety of questions about people’s functioning, diagnostic classification, co-morbidity, and choice of treatment approach.  For example, personality tests and inventories evaluate the thoughts, emotions, attitudes, and behavioral traits that contribute to an individual’s interpersonal functioning.  The results of these tests determine an individual's personality strengths and weaknesses, and may identify certain disturbances in personality, or psychopathology.  One type of personality test is the projective personality assessment, which asks a subject to interpret some ambiguous stimuli, such as a series of inkblots.  The subject's responses can provide insight into his or her thought processes and personality traits.

Neuropsychological testing is a subclassification of psychological testing anda well-established method for evaluating patients who demonstrate cognitive or behavioral abnormalities.  Neuropsychological testing is used when a differentiation between organic versus functional disorders is needed to direct proper therapy (e.g., occupational, physical, or speech and language therapy), predict neuropsychological recovery, or monitor progress.  Neuropsychological tests include: Halsted-Reitan neuropsychological battery or its components; Luria-Nebraska; Wechsler Adult Intelligence Scale (WAIS); Wechsler Intelligence Scales for Children - Revised (WISC-R); Wechsler Memory Scale; and the Reitan-Indiana neuropsychological test.

Neuropsychological testing may be necessary for persons with documented neurologic disease or injury (e.g., traumatic brain injury, stroke) when there is uncertainty about the degree of impairment, or when an organic deficit is present but information on anatomic location and extent of dysfunction is required.  An organic deficit is defined as a symptomatic manifestation of structural cerebral or systemic medical pathology, as opposed to being considered psychological or emotional in nature (functional).  Such testing can also be used to systematically track progress in rehabilitation after brain injury or other neurological disease.  Serial assessment in nonprogressive conditions, such as head injury, documents the patient’s rate of recovery and potential for returning  to work.

Neuropsychological testing is used in persons with documented changes in cognitive function to differentiate neurologic diseases (i.e., one of the types of dementia) or injuries (e.g., traumatic brain injury, stroke) from depressive disorders or other psychiatric conditions (e.g., psychosis, schizophrenia) when the diagnosis is uncertain after complete neurological examination, mental status examination, and other neurodiagnostic studies (e.g., CT scanning, MR imaging).  The clinician presented with complaints of memory impairment or slowness in thinking in a patient who is depressed or paranoid may be unsure of the possible contribution of neurological changes to the clinical picture.  Neuropsychological testing may be particularly helpful when the findings of the neurological examination and ancillary procedures are either negative or equivocal.  The differential diagnosis of incipient dementia from depression is a casein point, particularly when computed tomography (CT) fails to yield definitive results.

Neuropsychological testing may be indicated in persons with epilepsy or hydrocephalus.  Neuropsychological testing is used in these patients to monitor the efficacy and possible cognitive side effects of drug therapy (e.g., new anti-convulsant drug therapy) by comparing baseline performance with subsequent testing performance.  Neuropsychological testing is also used to assess post-surgical changes in cognitive functioning to guide further treatment services.  Preferably, these tests should be administered by a certified psychologist trained to conceptualize the neuro-anatomical and the neuro-behavioral implications of the diagnostic entities under consideration and who is capable of interpreting patterns of test scores in view of principles of lateralization and localization of cerebral function.

Neuropsychological testing is used for initial evaluation of cognitive deterioration associated with acquired immunedeficiency syndrome (AIDS), and for re-evaluation of persons with AIDS who show further deterioration, to distinguish between organic-based deterioration and deterioration from depression of chonic illness, in order to direct appropriate treatment.

Neuropsychological testing is also used in the initial evaluation of cognitive deterioration associated with Alzheimer’s disease.  It is also used for persons diagnosed with Alzheimer’s disease receiving medication for dementia, to evaluate deterioration in cognitive functioning to distinguish between diminished effect of the medication and organic worsening of the disease.  Serial administration of parallel forms of memory tests has been employed to investigate the effects of cholinergic agents and other drugs on dementia of the Alzheimer’s type.  Available medications for Alzheimer disease provide only a temporary cessation of the organic deterioration associated with Alzheimer’s disease, such that repeat testing may be necessary to aid in deciding whether or not to increase or discontinue the drug.

Neuropsychological testing typically takes up to 8 hours to perform, including administration, scoring and interpretation.  It is not necessary, as a general rule, to repeat neuropsychological testing at intervals less than 3 months apart.  In general, neuropsychological testing may not be as helpful in individuals over 65 years of age.

Psychological and neuropsychological testing has been used to assess of the neurotoxic effects of alcohol and/or drug abuse or dependence.  Chronic alcohol abuse can result in cognitive and memory defects which resolve to a varying degree depending on the duration of abstinence and the extent of neuronal loss or atrophy.  However, it is inappropriate to perform psychological and neuropsychological testing in a patient to assess the neurotoxic effects of alcohol or drug abuse or dependence during the detoxification period or within the early period of abstinence from the offending drug.  The results of psychological and neuropsychological assessment are unreliable when an individual is actively abusing alcohol or drugs and for some period of time after the acute phase of alcohol or drug withdrawal.

Psychological and neuropsychological testing has been used in the educational context in children with suspicion of a learning disorder leading to changes in school performance, so as to differentiate between mental subnormality, emotional disturbance, and the specific learning disabilities in speech and reading (e.g., dyslexia).  Psychological and neuropsychological testing are also used to develop a specialized treatment plan to help the child improve the performance of these cognitive functions leading to a better performance in school, work, and personal relationships.  However, psychological and neuropsychological testing for educational reasons is not covered, as standard Aetna benefit plans exclude educational testing.  In addition, psychological and neuropsychological testing performed for educational reasons is not considered treatment of disease.  This testing is usually provided by school systems under applicable state and federal rules.

Psychological and neuropsychological testing of children for the purpose of diagnosing attention deficit/hyperactivity disorder (ADHD) is not necessary, unless there is strong evidence of a possible neurological disorder.  There are few medical conditions which present with ADHD-like symptoms and most patients with ADHD have unremarkable medical histories.  In general, attention deficit disorders are best diagnosed through a careful history and the use of structured clinical interviews and dimensionally based rating scales.  Most psychologists obtain behavior ratings at home from the parents and at school from the teacher.  Examples of rating scales commonly used by psychologists are the Achembach Child Behavior Checklist, Connors Rating Scales, and the ADHD Symptoms Rating Scale.

Psychological and neuropsychological testing may used to assess functional competence in relationship to legal matters.  However, such use is not considered treatment of disease.  Psychological and neuropsychological testing performed as part of a research program is also not considered treatment of disease.

The types and numbers of neuropsychological tests given for each condition is not standardized.  Most psychologists will perform an in depth interview after the patient has filled out a standardized questionaire asking questions about history, symptoms and functioning, and based on this evaluation the psychologist will plan the testing regimen.

While neuropsychological testing may be useful to distinguish cognitive decline due to dementia from cognitive decline due to depression, its use in patients with chronic fatigue syndrome (CFS) has yet to be established.  Current evidence-based guidelines on chronic fatigue syndrome include no recommendation for neuropsychological testing in CFS.

Michiels and Cluydts (2001) reviewed the current status of neurocognitive studies in patients with CFS.  The authors concluded that the current research shows that slowed processing speed, impaired working memory and poor learning of information are the most prominent features of cognitive dysfunctioning in patients with CFS.  Furthermore, to this date no specific pattern of cerebral abnormalities has been found that uniquely characterizes CFS patients.  There authors stated that there is no overwhelming evidence that fatigue is related to cognitive performance in CFS, and researchers agree that their performance on neuropsychological tasks is unlikely to be accounted solely by the severity of the depression and anxiety.

Claypoole et al (2007) noted that variable reports of neuropsychological deficits in patients with CFS may be partly attributable to methodological limitations.  In this study, these researchers addressed these limitations by controlling for genetic and environmental influences and by assessing the effects of co-morbid depression and mode of illness onset.  Specifically, these researchers performed a co-twin control study of 22 pairs of monozygotic twins, in which 1 twin met strict criteria for CFS and the co-twin was healthy.  Twins underwent a structured psychiatric interview as well as comprehensive neuropsychological assessment evaluating 6 cognitive domains.  Results indicated that twin groups had similar intellectual and visual memory functioning, but fatigued twins exhibited decreases in motor functions (p = 0.05), speed of information processing (p = 0.02), verbal memory (p = 0.02), and executive functioning (p = 0.01).  Major depression did not affect neuropsychological functioning among fatigued twins, although twins with sudden illness onset demonstrated slowed information processing compared with those with gradual onset (p = 0.01).  Sudden onset CFS was associated with reduced speed of information processing.  If confirmed, these findings suggested the need to distinguish illness onset in future CFS studies and may have implications for treatment, cognitive rehabilitation, and disability determination.

Binder et al (2004) reviewed several illnesses that expressed somatically, but do not have clearly demonstrated pathophysiological origin and are associated with neuropsychological complaints.  Among them are CFS, non-epileptic seizures, fibromyalgia, Persian Gulf War unexplained illnesses, toxic mold and sick building syndrome, and silicone breast implant disease.  Some of these illnesses may be associated with objective cognitive abnormalities, but it is not likely that these abnormalities are caused by traditionally defined neurological disease.  Instead, the cognitive abnormalities may be caused by a complex interaction between biological and psychological factors.

Neuropsychological Testing for Evaluation of Migraineurs

Gil-Gouveia and colleagues (2016) noted that evidence of attack-related cognitive dysfunction in migraine is growing.  Controversy exists on whether cognitive dysfunction, mainly executive, may persist between attacks.  Measuring the impact of cognitive function is gaining importance in clinical and research settings in migraine.  These investigators compared the performance of inter-ictal migraine patients to controls in an assembled neuropsychological battery focused on executive functions and studied the practice effect of its repeated applications.  Assembly of the battery that was then applied twice within 6 weeks to inter-ictal migraineurs and matched healthy controls.  Migraine patients (n = 24) and controls (n = 24) had similar performance in both applications of the battery.  There was a slight practice effect between the first and second evaluation, significant in Stroop Interference test (p = 0.002, multiplicity corrected); a meaningful score change was determined for each raw test scores.  The authors concluded that inter-ictal migraineurs and controls performance was identical in a brief cognitive battery focused on executive functions; and repeated applications produced a practice effect that was quantified.

In a randomized, cross-sectional, within subject study, Huang and associates (2017) evaluated the changes in the cognitive performance of migraine patients using a comprehensive series of cognitive/behavioral and electrophysiological tests.  A total of 34 patients with migraine (6 men, 28 women, average age of 36 years) were included.  Migraineurs performed worse in the majority of the Montreal Cognitive Assessment (MoCA) (p = 0.007) compared to the healthy subjects, significantly in language (p = 0.005), memory (p = 0.006), executive functions (p = 0.042), calculation (p = 0.018) and orientation (p = 0.012).  Migraineurs had a lower score on the memory trial of the Rey-Osterrieth complex figure test (ROCF) (p = 0.012).  The P3 latency in Fz, Cz, Pz was prolonged in migraineurs compared with the normal control group (p < 0.001).  In addition, these researchers analyzed significant correlations between MoCA score and the duration of migraine.  They also observed that a decrease in the MoCA-executive functions and calculation score and in the ROCF-recall score were both correlated to the frequency of migraine.  Migraineurs were more anxious than healthy subjects (p = 0.001), which was independent of cognitive testing.  Differences were unrelated to age, gender and literacy.  The authors concluded that these findings suggested the existence of brain dysfunction during attacks of migraine, which be related to the duration and frequency of a migraine attack.

This study had several drawbacks:

1. the study sample (n = 34) limited the ability to examine the effects of gender, age and education;
2. a previous study has shown that migraineurs with aura tended to exhibit even less decline over time than migraineurs overall.  These researchers did not find differences in mean cognitive scores between migraineurs with and without aura.  However, this was likely to due to the sample sizes and resulting low statistical power.  de Tommaso et al (2014) found that the changes in brain responsivity were associated with various stages of the migraine cycle, since migraine patients appeared to have a response augmentation and poor habituation that normalizes just before/during attacks.  In this study, patients were observed outside migraine attacks, but they could be at different points of a migraine cycle.  These investigators did not record the last time that they had a migraine attack; and
3. these researchers did not observe the cognition of migraine patients at multiple time-points, which limited them from examining the change in cognitive function over time.

Computerized Neuropsychological Assessment Devices for Screening and Monitoring Multiple Sclerosis-Related Cognitive Impairment

Wojcik and colleagues (2019) noted that the proliferation of computerized neuropsychological assessment devices (CNADs) for screening and monitoring cognitive impairment is increasing exponentially.  Previous reviews of computerized tests for multiple sclerosis (MS) were primarily qualitative and did not rigorously compare CNADs on psychometric properties.  These investigators systematically reviewed the literature on the use of CNADs in MS and identified test batteries and single tests with good evidence for reliability and validity.  They search of 4 major online data-bases for publications related to computerized testing and MS.  Test-retest reliability and validity coefficients and effect sizes were recorded for each CNAD test, along with administration characteristics.  These researchers identified 11 batteries and 33 individual tests from 120 peer-reviewed articles meeting the inclusion criteria.  CNADs with the strongest psychometric support include the CogState Brief Battery, Cognitive Drug Research Battery, NeuroTrax, CNS-Vital Signs, and computer-based administrations of the Symbol Digit Modalities Test.  The authors identified several CNADs that are valid to screen for MS-related cognitive impairment, or to supplement full, conventional neuropsychological assessment.  The necessity of testing with a technician, and in a controlled clinic/laboratory environment, remains uncertain.  They opined that CNADs are quite good at measuring cognitive processing speed in MS, and their sensitivity and validity in other domains merit further investigation.  The authors concluded that several computerized tests of cognition are available and applied in MS research.  As they currently stand, most CNAD batteries and individual tests do not yet demonstrate adequate reliability and validity to supplant well-established conventional neuropsychological procedures such as MS Cognitive Endpoints battery (MS-COG), BICAMS (Brief International Cognitive Assessment for MS), or MACFIMS (Minimal Assessment of Cognitive Function in MS).  However, some tests (e.g., certain subtests of the CDR, CBB, NeuroTrax, CNSVS, C-SDMT, PST, and CSCT) possess psychometric qualities that approach or maybe even exceed conventional, person-administered tests and can serve as useful screening tools or supplements to full assessments.  Further investigations of these CNADs, especially as they relate to ecological measures and patient-relevant outcomes, are needed before widespread implementation with an MS population.

Bottrich and associates (2020) stated that the assessment of neuropsychological functions and especially dual-tasking abilities is considered to be increasingly relevant in the assessment of neurological disease, and in particular, MS.  However, the assessment of dual-tasking abilities is hindered by specific software requirements and extensive testing times.  In a proof-of-concept pilot study, these researchers designed a novel e-health (progressive web application-based) device for the assessment of dual-tasking abilities usable in "bedside" and out-patient clinic settings and examined its reliability in a sample of  MS patients (n = 184) in an out-patient setting.  Moreover, these investigators examined the relevance of dual-tasking assessment using this device with respect to clinically relevant parameters in MS.  They demonstrated that a meaningful assessment of dual-tasking was possible within 6 mins and that the behavioral read-outs overall showed good reliability depending on dual-tasking difficulty.  These researchers showed that dual-tasking read-outs were correlated with clinically relevant parameters (e.g., the Expanded Disability Status Scale [EDSS], disease duration, processing speed) and were not affected by fatigue levels.  They considered the tested dual-tasking assessment device suitable for routine clinical neuropsychological assessments of dual-tasking abilities.  The authors concluded that the findings of this study underlined the reliability of the developed tablet-based assessment tool for dual-tasking abilities in MS patients.  The results showed that it is possible to carry out a reliable assessment of multi-tasking abilities in approximately 6 mins.  These researchers considered this duration acceptable for routine clinical neuropsychological assessments of dual-tasking abilities.  As such, the presented assessment tool appeared suitable to address a clinical need to examine dual-tasking.  Moreover, they stated that future studies may also examine this assessment tool regarding its suitability in the long-term follow-up assessments of MS patients and to evaluate dual-tasking abilities in other neurological and psychiatric disorders.

The authors stated that this study had several drawbacks.  To determine the reliability of this novel tablet-computer based implementation of the psychological refractory period (PRP), the internal consistency was determined.  In contrast to the retest-reliability, the internal consistency does not rely on the assumption that the construct being measured does not change over time.  Assessing the internal consistency of the 3 consecutive blocks containing exactly the same sequence of trials helped to address the question of both internal consistency and stability.  However, stability over longer periods of time could not be assumed for a patient group with presumably active disease progression.  Future studies may, however, even in patients with a disease characterized by progression and relapses, achieve results by adopting strict inclusion/exclusion criteria (absence of relapses in the last 3 months and during the study), and using a short test-retest interval (e.g., few days apart).  The inter-method reliability could not be determined in this study because a direct comparison of the novel dual-task implementation with a conventional keyboard-based implementation was not carried out.  However, an at least satisfactory inter-method/parallel-form reliability can be assumed, since both the novel implementation and the conventional personal computer-based PRP implementation reliably produced a PRP effect.  Future validation steps of this dual-task implementation should include a direct comparison of both implementations and may also integrate structural MRI to examine the effects of brain structural abnormalities and their change in MS.  In addition, handedness may influence speeded responses to the second task stimulus, but was not examined in this study.  Although it can be assumed that reaction time differences due to handedness should be evenly distributed across all stimulus-onset asynchrony levels, and thus should not significantly influence the PRP effect, future validation steps should consider the effects of handedness.

Diagnostic Assessment for Neurodiversity

A diagnostic assessment for neurodiversity (neurodiversity tests) may be used when a person is experiencing significant difficulties in the workplace or in daily life and does not already have a diagnosis of a specific learning difficulty.  The tests are designed to see if an individual has traits of neurodiversity (e.g., autism spectrum disorder [ASD], attention-deficit hyperactivity disorder [ADHD], developmental language dyslexia [DD], dyspraxia, obsessive-compulsive disorder [OCD], or Tourette syndrome).  However, the results do not confer a diagnosis; they are used to indicate whether an individual may have traits of that neurodivergence.  Following the assessment, a person may be referred to other organizations for further evaluations for specific learning difficulties; and may receive recommendations regarding how to support him/her in the context of study, workplace or daily life.  It should be noted that any recommendations of how a person could be supported in the workplace are usually generic and not job specific.

Barnhart and Dierickx (2021) stated that research with cerebral organoids is beginning to make significant progress in understanding the etiology of ASD.  Brain organoid models can be grown from the cells of donors with ASD . Researchers can examine the genetic, developmental, and other factors that may give rise to the varieties of autism.  Researchers could examine all of these factors together with brain organoids grown from cells originating from ASD individuals.  This makes brain organoids unique from other forms of ASD research.  They are like a multi-tool, one with significant versatility for the scope of ASD research and clinical applications.  There is hope that brain organoids could one day be used for precision medicine, like developing tailored ASD pharmacotherapies.  Brain organoid researchers often incorporate the medical model of disability when researching the origins of ASD, especially when the research has the specific objective of potentially finding tailored clinical treatments for ASD individuals.  The neurodiversity movement -- a developmental disability movement and paradigm that understands autism as a form of natural human diversity -- will potentially disagree with approaches or aims of cerebral organoid research on ASD.  Neurodiversity advocates incorporate a social model of disability into their movement, which focuses more on the social, attitudinal, and environmental barriers rather than biophysical or psychological deficits; thus, a potential conflict may arise between these perspectives on how to proceed with cerebral organoid research regarding neurodevelopmental conditions, especially ASD.  The authors presented these perspectives and provided at least 3 initial recommendations to achieve a more holistic and inclusive approach to cerebral organoid research on ASD.  These 3 initial starting points could build bridges between researchers and the neurodiversity movement.  First, neurodiverse individuals should be included as co-creators in both the scientific process and research communication.  Second, clinicians and neurodiverse communities should have open and respectful communication.  Third, the authors suggested a continual reconceptualization of illness, impairment, disability, behavior, and person.

Dwyer (2022) presented the concepts of "neurodiversity" and the "neurodiversity approaches" towards disability and discussed how confusion regarding the meaning of these concepts exacerbates debate and conflict regarding the neurodiversity approaches.  For example, some claimed the neurodiversity approaches focus solely on society and deny contributions of individual characteristics to disability (a controversial stance), whereas the author joined other investigators in acknowledging the contributions of both individual and society to disability.  This article also addressed other controversies related to neurodiversity, such as uncertainty regarding the scope of the approaches -- to whom do they apply? -- and their implications for diagnostic categories.  Furthermore, the author provided recommendations for developmental researchers who wish to conduct neurodiversity-aligned research: investigators are urged to examine both individual neurodivergent individuals and the contexts around them; to consider both strengths and weaknesses; to recognize their own biases; and to listen to and learn from neurodivergent individuals.

In a systematic review, de Beer et al (2022) focused on workers with developmental dyslexia (DD).  In this review DD is considered an expression of neurodiversity, a consequence of a natural variant of the brain.  Evidence was synthesized to examine which factors workers with DD consider relevant for their participation in work and whether these factors reflect shifts in the concepts of health and sustainable employability.  The factors were classified according to the International Classification of Functioning, Disability and Health (ICF), adapted for occupational health.  Two search strings were employed to determine the population and the context of work.  The factors were classified using a recently proposed re-arrangement of the ICF scheme that placed participation in a central position and incorporated preliminary lists of work-related environmental factors and personal factors.  A total of 51 factors were found that appeared in 35 % or more of the included studies and that were relevant to work participation according to the workers themselves.  These factors were dispersed over all ICF categories.  In the category Functions and Structures (11 factors), most of the factors had negative connotations.  In the category Activities (9 factors), all the factors caused difficulties, except speaking (which was ambiguous).  In the category Participation (4 factors), the formal relationships were important for the degree of participation.  Overall, more than 50 % of the factors were environmental (18) or personal (9) and they both hindered and facilitated work participation.  The authors concluded that the findings of this review provided an indication for the importance of the biopsychosocial model as a relevant approach for individuals with a disability in the workplace.  This review also added data for the usefulness of the proposals for the re-consideration of the ICF scheme.  The data have not (yet) returned any visible trends revealing that the concept of neurodiversity is common in organizations.

There is a lack of evidence regarding the clinical value of neurodiversity tests; UpToDate (2022) provides no pertinent information on “diagnostic assessment for neurodiversity”.

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