Arnadottir OT-ADL Neurobehavioural Evaluation (A-ONE)

Purpose

The Arnadottir OT-ADL Neurobehavioural Evaluation (A-One) evaluates the impact of neurobehavioural impairment on functional performance of activities of daily living (ADL)Basic tasks that involve bodily issues (bathing, dressing, toileting, transferring, continence, eating and walking) that are done on a daily basis..

In-Depth Review

Purpose of the measure

The Arnadottir OT-ADL Neurobehavioural Evaluation (A-One) is a standardized, performance-based measure that identifies the impact of neurobehavioural impairment on functional performance of ADL. The measure allows observation of ADL and evaluation of the level of assistance required for ADL performance (Arnadottir et al., 2009). Accordingly, the A-ONE provides the therapist with an ecologically-relevant assessment of the consequences of neurobehavioural impairments through clinical observation of ADL tasks using a ‘top-down’ (occupation-based) approach (Arnadottir et al., 2009; Bottari et al., 2006; Carswell et al., 1992; Cooke et al., 2006).

The A-ONE is comprised of two parts: (a) assessment of the individual’s independence in ADL tasks and the type of assistance required; and (b) identification of the type and severity of neurobehavioural impairment that is limiting the individual’s independence in these tasks (Gardarsdottir & Kaplan, 2002).

The A-ONE can be used to assist therapists in goal setting and treatment planningPlanning ability involves anticipating future events, formulating a goal or endpoint, and devising a sequence of steps or actions that will achieve the goal or endpoint" (Anderson, 2008, p. 17)
(Gardarsdottir & Kaplan, 2002).

Available versions

The A-ONE was previously named the Arnadottir Occupational Therapy – ADL (OT-ADL) Neurobehavioural Evaluation.

Features of the measure

Items:
The A-ONE is comprised of 2 scales: the Functional Independence scale, more commonly referred to as the ActivitiesAs defined by the International Classification of Functioning, Disability and Health, activity is the performance of a task or action by an individual. Activity limitations are difficulties in performance of activities. These are also referred to as function.
of Daily Living Scale (ADL scale), and the Neurobehavioural Impairment scale (NBI scale).

The ADL scale measures 5 ADL domains (dressing; grooming and hygiene; transfers and mobility; feeding; and communication) using 20 everyday tasks.

1. Dressing

• i. Put on shirt
• ii. Put on pants
• iii. Put on socks
• iv. Put on shoes
• v. Manipulate fastenings

2. Grooming and hygiene

• i. Wash face
• ii. Comb hair
• iii. Brush teeth
• iv. Shave beard/apply cosmetics
• v. Perform toilet hygiene
• vi. Bathe

3. Transfers and mobility

• i. Sit up in bed
• ii. Transfer from sitting
• iii. Maneuver around
• iv. Transfer to toilet
• v. Transfer to tub

4. Feeding

• i. Drink from glass/cup
• ii. Use fingers to bring food to mouth
• iii. Bring food to mouth by fork or spoon
• iv. Use knife to cut and spread

5. Communication

The NBI scale consists of items to assist the therapist in identifying the probable site of cortical dysfunction based on the observed neurological behaviours. The NBI scale is comprised of 2 subscales:

1. The Specific SubscaleMany measurement instruments are multidimensional and are designed to measure more than one construct or more than one domain of a single construct. In such instances subscales can be constructed in which the various items from a scale are grouped into subscales. Although a subscale could consist of a single item, in most cases subscales consist of multiple individual items that have been combined into a composite score (National Multiple Sclerosis Society).
Impairment (NBSIS) subscaleMany measurement instruments are multidimensional and are designed to measure more than one construct or more than one domain of a single construct. In such instances subscales can be constructed in which the various items from a scale are grouped into subscales. Although a subscale could consist of a single item, in most cases subscales consist of multiple individual items that have been combined into a composite score (National Multiple Sclerosis Society).

• i. Motor apraxia
• ii. Ideational apraxia
• iii. Unilateral body neglect
• iv. Spatial relations
• v. Unilateral spatial neglect
• vi. Organization and sequencing“The coordination and proper ordering of the steps that comprise the task, requiring a proper allotment of attention to each step” (Lezak, 1989; as cited in (Baum, Morrison, Hahn & Edwards, 2007))
  
• vii. Perseveration
• viii. Topographical disorientation (transfers and mobility)
• ix. Sensory aphasiaAphasia is an acquired disorder caused by an injury to the brain and affects a person’s ability to communicate. It is most often the result of stroke or head injury.
  An individual with aphasia may experience difficulty expressing themselves when speaking, difficulty understanding the speech of others, and difficulty reading and writing. Sadly, aphasia can mask a person’s intelligence and ability to communicate feelings, thoughts and emotions. (The Aphasia Institute, Canada) (communication)
• x. Anomia (communication)
• xi. Paraphasia (communication)
• xii. Expressive aphasiaAphasia is an acquired disorder caused by an injury to the brain and affects a person’s ability to communicate. It is most often the result of stroke or head injury.
  An individual with aphasia may experience difficulty expressing themselves when speaking, difficulty understanding the speech of others, and difficulty reading and writing. Sadly, aphasia can mask a person’s intelligence and ability to communicate feelings, thoughts and emotions. (The Aphasia Institute, Canada) (communication)

2. The Pervasive SubscaleMany measurement instruments are multidimensional and are designed to measure more than one construct or more than one domain of a single construct. In such instances subscales can be constructed in which the various items from a scale are grouped into subscales. Although a subscale could consist of a single item, in most cases subscales consist of multiple individual items that have been combined into a composite score (National Multiple Sclerosis Society).
Impairment (NBPSI) subscaleMany measurement instruments are multidimensional and are designed to measure more than one construct or more than one domain of a single construct. In such instances subscales can be constructed in which the various items from a scale are grouped into subscales. Although a subscale could consist of a single item, in most cases subscales consist of multiple individual items that have been combined into a composite score (National Multiple Sclerosis Society).

• i. Lability
• ii. Apathy
• iii. DepressionIllness involving the body, mood, and thoughts, that affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. A depressive disorder is not the same as a passing blue mood or a sign of personal weakness or a condition that can be wished away. People with a depressive disease cannot merely “pull themselves together” and get better. Without treatment, symptoms can last for weeks, months, or years. Appropriate treatment, however, can help most people with depression.
  
• iv. Irritability
• v. Frustration
• vi. Restlessness
• vii. Insight
• viii. Judgement
• ix. Confusion
• x. Attention
• xi. Distraction
• xii. Initiative
• xiii. Motivation
• xiv. Performance latency
• xv. Working memoryExecutive process responsible for the temporary storage and manipulation of information in both simple (e.g. recalling a series of digits such as a phone number) and complex cognitive tasks (e.g. coordinating two tasks simultaneously) (Van der Linden, 2007)
  
• xvi. Confabulation

Description of tasks:
The therapist observes the patient performing the listed ADL tasks and determines the level of assistance required to complete the tasks (see scoring below). Errors in task performance are an indication of underlying neurobehavioural impairments. Different neurobehavioural impairments manifest as different errors or difficulties in ADL task performance. The therapist observes for the presence and severity of neurobehavioural impairments, according to how much the impairment impacts on the individual’s ability to perform the ADL task independently (Gardarsdottir & Kaplan, 2002; Arnadottir et al., 2009).

What to consider before beginning:
The A-ONE should be performed in the clinical setting (Bottari et al., 2006).

Scoring and Score Interpretation:
The ADL and the Neurobehavioural linear scales were developed as criterion-referenced rating scales of the ordinal type by application of Rasch analysisRasch analysis is a statistical measurement method that allows the measurement of an attribute – such as upper limb function – independently of particular tests or indices.   It creates a linear representation using many individual items, ranked by item difficulty (e.g. picking up a very small item, versus a task requiring a very gross grasp) and person ability.   A well performing Rasch model will have items hierarchically placed from simple to more difficult, and individuals with high abilities should be able to perform all the items below a level of difficulty.  The Rasch model is statistically strong because it enables ordinal measures to be converted into meaningful interval measures. It also allows information from various tests or tools with different scoring systems to be applied using the Rasch model.
(Arnadottir & Fisher, 2008; Arnadottir et al., 2010).

The ADL scale measures the individual’s need for assistance to overcome neurobehavioural impairments during ADL task performance. Arnadottir et al. (2008) examined the original 5-point rating scale structure and noted that thresholds were disordered. This disorder was eliminated when score 2 (verbal assistance) and score 3 (supervision) were combined, resulting in a 4-point rating scale:

0 = Full assistance needed
1 = Minimum to considerable physical assistance needed
2 = Verbal assistance/supervision needed
3 = Independent

Scores can be added within each ADL domain, but total ADL scores should not be added. Individuals are not penalized for using assistive devicesAssistive devices are any piece of equipment that you use to make your daily activities easier to perform.
when performing ADL tasks (Arnadottir et al., 2008).

Scoring of the NBI scale is based on the extent to which the neurobehavioural impairment interferes with ADL task performance, not the severity of the impairment. Most items of the NBSIS are rated several times:

1. Motor apraxia*
2. Ideational apraxia*
3. Unilateral body neglect*
4. Spatial relations*
5. Unilateral spatial neglect*
6. Organization and sequencing“The coordination and proper ordering of the steps that comprise the task, requiring a proper allotment of attention to each step” (Lezak, 1989; as cited in (Baum, Morrison, Hahn & Edwards, 2007))
   *
7. Perseveration^
8. Topographical disorientation (transfers and mobility)
9. Sensory aphasiaAphasia is an acquired disorder caused by an injury to the brain and affects a person’s ability to communicate. It is most often the result of stroke or head injury.
   An individual with aphasia may experience difficulty expressing themselves when speaking, difficulty understanding the speech of others, and difficulty reading and writing. Sadly, aphasia can mask a person’s intelligence and ability to communicate feelings, thoughts and emotions. (The Aphasia Institute, Canada) (communication)
10. Anomia (communication)
11. Paraphasia (communication)
12. Expressive aphasiaAphasia is an acquired disorder caused by an injury to the brain and affects a person’s ability to communicate. It is most often the result of stroke or head injury.
    An individual with aphasia may experience difficulty expressing themselves when speaking, difficulty understanding the speech of others, and difficulty reading and writing. Sadly, aphasia can mask a person’s intelligence and ability to communicate feelings, thoughts and emotions. (The Aphasia Institute, Canada) (communication)

* scored 4 times (during dressing; grooming and hygiene; transfers and mobility; and feeding ADL tasks)

^ scored 5 times (during all ADL tasks)

Items that are rated more than once are scored using a 5-point ordinal rating scale, from 0 = the particular neurobehavioural impairment is not observed, to 4 = the patient is unable to perform the task due to the neurobehavoural impairment. All other items (including communication items from the NBSIS and all items from the NBPSI are rated dichotomously: 0 = absent or 1 = present during ADL task performance (Arnadottir et al., 2009).

The manual includes conceptual and operational definitions for all items as well as standardized instruction and detailed criteria for administration and scoring of the instrument.

Time:
Time taken to administer the A-ONE has not been reported.

Equipment:
Not reported

Alternative forms of the assessment

The author has developed several variations of the NBI scale including 2 global scales and 4 psychometrically-sound diagnostic-specific scales (Arnadottir, 2010):

• Common global scale (NBI-CVA, 53 items)
• NBI common short form scale (29 items)
• Left-hemisphere CVA (NBI-LCVA, 42 items)
• Right-hemisphere CVA (NBI-RCVA, 51 items)
• Dementia Alzheimers Type (NBI-DAT, 49 items)
• Dementia Unspecified (NBI-DU, 40 items).

The scales contain different items and hierarchical structure. These versions can be used across diagnostic groups but should not be used to compare different diagnostic groups (Arnadottir, 2010).

Client suitability

Can be used with:

• The A-ONE can be used with patients with dementia and other neurological disorders (Gardarsdottir & Kaplan, 2002).

Should not be used with:

• As the A-ONE has been designed for use with adults with neurobehavioural disorders, it is not recommended for use with individuals with other diagnoses or disorders.

Languages of the measure

English, Dutch

Summary

What does the tool measure?	The Arnadottir OT-ADL Neurobehavioural Evaluation (A-One) measures the impact of neurobehavioural impairment on functional performance of ADLs. The A-ONE is used to assess (a) independence in ADL tasks and (b) neurobehavioural impairments that limit the individual’s independence in ADL tasks.
What types of clients can the tool be used for?	The A-ONE is designed for use with adults with neurological dysfunction of cortical origin, including strokeAlso called a “brain attack” and happens when brain cells die because of inadequate blood flow. 20% of cases are a hemorrhage in the brain caused by a rupture or leakage from a blood vessel. 80% of cases are also know as a “schemic stroke”, or the formation of a blood clot in a vessel supplying blood to the brain. More, dementia, Alzheimer’s disease and other neurological disorders.
Is this a screeningTesting for disease in people without symptoms. or assessment tool?	Assessment tool.
Time to administer	The A-ONE ADL scale takes approximately 25 minutes to administer.
Versions	There is only 1 version of the ADL scale but there are several versions of the neurobehavioural scale: Common global scale (NBI-CVA) NBI common short form scale Left-hemisphere CVA (NBI-LCVA) Right-hemisphere CVA (NBI-RCVA) Dementia Alzheimers Type (NBI-DAT) Dementia Unspecified (NBI-DU). There is a Dutch version of the A-ONE.
Other Languages	English and Dutch.
Measurement Properties
ReliabilityReliability can be defined in a variety of ways. It is generally understood to be the extent to which a measure is stable or consistent and produces similar results when administered repeatedly. A more technical definition of reliability is that it is the proportion of “true” variation in scores derived from a particular measure. The total variation in any given score may be thought of as consisting of true variation (the variation of interest) and error variation (which includes random error as well as systematic error). True variation is that variation which actually reflects differences in the construct under study, e.g., the actual severity of neurological impairment. Random error refers to “noise” in the scores due to chance factors, e.g., a loud noise distracts a patient thus affecting his performance, which, in turn, affects the score. Systematic error refers to bias that influences scores in a specific direction in a fairly consistent way, e.g., one neurologist in a group tends to rate all patients as being more disabled than do other neurologists in the group. There are many variations on the measurement of reliability including alternate-forms, internal consistency , inter-rater agreement , intra-rater agreement , and test-retest .	Internal consistencyA method of measuring reliability . Internal consistency reflects the extent to which items of a test measure various aspects of the same characteristic and nothing else. Internal consistency coefficients can take on values from 0 to 1. Higher values represent higher levels of internal consistency. More: – One study reported adequate internal consistencyA method of measuring reliability . Internal consistency reflects the extent to which items of a test measure various aspects of the same characteristic and nothing else. Internal consistency coefficients can take on values from 0 to 1. Higher values represent higher levels of internal consistency. More of the ADL scale (α = 0.75 – 0.79), poor to adequate internal consistencyA method of measuring reliability . Internal consistency reflects the extent to which items of a test measure various aspects of the same characteristic and nothing else. Internal consistency coefficients can take on values from 0 to 1. Higher values represent higher levels of internal consistency. More of the NBSIS scale (α= 0.69 – 0.75), and poor internal consistence of the NBPIS scale (α= 0.59 – 0.63) using Cronbach’s alpha. – One study reported excellent internal consistencyA method of measuring reliability . Internal consistency reflects the extent to which items of a test measure various aspects of the same characteristic and nothing else. Internal consistency coefficients can take on values from 0 to 1. Higher values represent higher levels of internal consistency. More (item separation reliabilityReliability can be defined in a variety of ways. It is generally understood to be the extent to which a measure is stable or consistent and produces similar results when administered repeatedly. A more technical definition of reliability is that it is the proportion of “true” variation in scores derived from a particular measure. The total variation in any given score may be thought of as consisting of true variation (the variation of interest) and error variation (which includes random error as well as systematic error). True variation is that variation which actually reflects differences in the construct under study, e.g., the actual severity of neurological impairment. Random error refers to “noise” in the scores due to chance factors, e.g., a loud noise distracts a patient thus affecting his performance, which, in turn, affects the score. Systematic error refers to bias that influences scores in a specific direction in a fairly consistent way, e.g., one neurologist in a group tends to rate all patients as being more disabled than do other neurologists in the group. There are many variations on the measurement of reliability including alternate-forms, internal consistency , inter-rater agreement , intra-rater agreement , and test-retest . coefficient = 0.98, item separation index = 8.02; person separation reliabilityReliability can be defined in a variety of ways. It is generally understood to be the extent to which a measure is stable or consistent and produces similar results when administered repeatedly. A more technical definition of reliability is that it is the proportion of “true” variation in scores derived from a particular measure. The total variation in any given score may be thought of as consisting of true variation (the variation of interest) and error variation (which includes random error as well as systematic error). True variation is that variation which actually reflects differences in the construct under study, e.g., the actual severity of neurological impairment. Random error refers to “noise” in the scores due to chance factors, e.g., a loud noise distracts a patient thus affecting his performance, which, in turn, affects the score. Systematic error refers to bias that influences scores in a specific direction in a fairly consistent way, e.g., one neurologist in a group tends to rate all patients as being more disabled than do other neurologists in the group. There are many variations on the measurement of reliability including alternate-forms, internal consistency , inter-rater agreement , intra-rater agreement , and test-retest . coefficient = 0.90, person separation index = 2.93) using Rasch analysisRasch analysis is a statistical measurement method that allows the measurement of an attribute – such as upper limb function – independently of particular tests or indices.   It creates a linear representation using many individual items, ranked by item difficulty (e.g. picking up a very small item, versus a task requiring a very gross grasp) and person ability.   A well performing Rasch model will have items hierarchically placed from simple to more difficult, and individuals with high abilities should be able to perform all the items below a level of difficulty.  The Rasch model is statistically strong because it enables ordinal measures to be converted into meaningful interval measures. It also allows information from various tests or tools with different scoring systems to be applied using the Rasch model. . Test-retest: One study reported excellent one-week test-retest reliabilityA way of estimating the reliability of a scale in which individuals are administered the same scale on two different occasions and then the two scores are assessed for consistency. This method of evaluating reliability is appropriate only if the phenomenon that the scale measures is known to be stable over the interval between assessments. If the phenomenon being measured fluctuates substantially over time, then the test-retest paradigm may significantly underestimate reliability. In using test-retest reliability, the investigator needs to take into account the possibility of practice effects, which can artificially inflate the estimate of reliability (National Multiple Sclerosis Society). of the A-ONE (agreement of 0.85 or higher for all items). Intra-rater: No studies have reported on intra-rater reliabilityThis is a type of reliability assessment in which the same assessment is completed by the same rater on two or more occasions. These different ratings are then compared, generally by means of correlation. Since the same individual is completing both assessments, the rater’s subsequent ratings are contaminated by knowledge of earlier ratings. of the A-ONE. Inter-rater: Two studies have reported excellent inter-rater reliabilityA method of measuring reliability . Inter-rater reliability determines the extent to which two or more raters obtain the same result when using the same instrument to measure a concept. for the A-ONE ADL scale (kappa = 0.83; weighted kappa=0.90; ICC=0.98; Kendall’s r=0.92), the NB scale (kappa = 0.85) or the NBSIS scale (ICC=0.93, weighted kappa=0.74).
ValidityThe degree to which an assessment measures what it is supposed to measure.	– One study reported logical ordering of ADL items according to difficulty, but noted large gaps in the hierarchy of item difficulty in some NBI scales. – One study reported that the ADL scale may not be well targeted to higher functioning individuals. – One study reported a moderate inverse relationship between ADL and neurobehavioural impairment scales, using Pearson product moment correlationThe most commonly used method of computing a correlation coefficient between variables that are linearly related. Pearson’s r is a measure of association which varies from -1 to +1, with 0 indicating no relationship (random pairing of values) and 1 indicating perfect relationship (r=-0.57). Content: – Content validityRefers to the extent to which a measure represents all aspects of a given social concept. Example: A depression scale may lack content validity if it only assesses the affective dimension of depression but fails to take into account the behavioral dimension. of the A-ONE is based on literature review and expert opinion. – Internal validityThe degree to which an assessment measures what it is supposed to measure. of the A-ONE is determined by examination of goodness of fit for items, logical hierarchical ordering of items, targeting, and PCA analysis. – One study reported unidimensionality of the ADL scale and logical hierarchical ordering of ADL items. – One study reported unidimensionality of the NBI scales. Criterion: Concurrent: One study reporConted excellent correlations between the A-ONE ADL scale and the Barthel Index (r=0.70), and between the A-ONE and the MMSE (r=0.85). Predictive: No studies have reported on the predictive validityA form of criterion validity that examines a measure’s ability to predict some subsequent event. Example: can the Berg Balance Scale predict falls over the following 6 weeks? The criterion standard in this example would be whether the patient fell over the next 6 weeks. of the A-ONE. Construct: One study reported that the ADL scale has three factors and the NBSIS scale has 2 factors. A later study reported that the NBSIS scale has a third factor. Convergent/Discriminant: No studies have reported on the convergent or discriminant validityMeasures that should not be related are not. Discriminant validity examines the extent to which a measure correlates with measures of attributes that are different from the attribute the measure is intended to assess. of the A-ONE. Known Groups: – One study reported no significant difference in the extent of the impact of neurobehavioural impairment on ADL between patients with right CVA and left CVA. – One study reported significant differences between adults with right and left CVA on the ADL scale and the NBSIS scale.
Floor/Ceiling Effects	The A-ONE ADL scale and neurobehavioural scales demonstrate potential floor/ceiling effects. The ADL scale should be restricted to individuals who are not independent in ADLs. The NBI-CVA should be used clinically with patients with LCVA due to ceiling effects of the NBI-LCVA scale.
SensitivitySensitivity refers to the probability that a diagnostic technique will detect a particular disease or condition when it does indeed exist in a patient (National Multiple Sclerosis Society). See also “Specificity.” /Specificity	No studies have reported on the sensitivitySensitivity refers to the probability that a diagnostic technique will detect a particular disease or condition when it does indeed exist in a patient (National Multiple Sclerosis Society). See also “Specificity.” /specificity of the A-ONE.
Does the tool detect change in patients?	The ADL ordinal rating scale can be used as an interval scale, which allows measurement of change in ADL task performance over time.
Acceptability	No studies have reported on the acceptability of the A-ONE.
Feasibility	No studies have reported on the feasibility of the A-ONE.
How to obtain the tool?	The A-ONE can be found in the textbook The Brain and Behavior: Assessing Cortical Dysfunction Through ActivitiesAs defined by the International Classification of Functioning, Disability and Health, activity is the performance of a task or action by an individual. Activity limitations are difficulties in performance of activities. These are also referred to as function. of Daily Living For more information email: a-one@islandia.is

Psychometric Properties

Overview

A literature search was conducted to identify all relevant publications on the psychometric properties of the Arnadottir OT-ADL Neurobehavioural Evaluation (A-ONE). Nine articles were reviewed.

Floor/Ceiling Effects

In a study of the psychometric properties of the ADL scale Arnadottir et al. (2008) reported that 9 of 209 participants with left hemisphere strokeAlso called a "brain attack" and happens when brain cells die because of inadequate blood flow. 20% of cases are a hemorrhage in the brain caused by a rupture or leakage from a blood vessel. 80% of cases are also know as a "schemic stroke", or the formation of a blood clot in a vessel supplying blood to the brain. More (LHS) reached maximum scores on all items, indicating possible ceiling effects of the scale. The authors concluded that use of the A-ONE should be restricted to individuals who are not independent in ADLs (where maximum scores indicate independence in ADLs). However, while a patient may achieve maximum scores on the ADL scale, they may demonstrate neurobehavioural impairments that can be detected using the NBI scale (Arnadottir, 2010).

In a study of the psychometric properties of the neurobehavioural scales Arnadottir et al. (2009) reported potential floor/ceiling effects of the measure. Two patients with LCVA and 6 patients with RCVA attained extreme (minimum) scores. Extreme (maximum) measures were seen on 10 items when used with patients with LCVA and on 4 items when used with patients with RCVA.

Following refinement of the NBI scales and development of additional versions of the scale, further analysis was conducted using Rasch analysisRasch analysis is a statistical measurement method that allows the measurement of an attribute - such as upper limb function - independently of particular tests or indices.   It creates a linear representation using many individual items, ranked by item difficulty (e.g. picking up a very small item, versus a task requiring a very gross grasp) and person ability.   A well performing Rasch model will have items hierarchically placed from simple to more difficult, and individuals with high abilities should be able to perform all the items below a level of difficulty.  The Rasch model is statistically strong because it enables ordinal measures to be converted into meaningful interval measures. It also allows information from various tests or tools with different scoring systems to be applied using the Rasch model.
(Arnadottir, 2010). Results indicated that 30 of 422 patients with CVA or dementia achieved maximum or minimum scores on the 29-item NBI-Common scale; 6 of 215 patients with left-hemisphere or right-hemisphere CVA achieved maximum or minimum scores on the 53-item NBI-CVA scale; 9 of 114 patients with LCVA achieved maximum or minimum scores on the 42-item NBI-LCVA scale; and 0 of 108 patients with RCVA achieved maximum or minimum scores on the 51-item NBI-RCVA scale. Arnadottir (2010) recommended the NBI-CVA for clinical use with patients with LCVA due to the possible ceiling effectA ceiling effect occurs when test items aren't challenging enough for a group of individuals. Thus, the test score will not increase for a subsample of people who may have clinically improved because they have already reached the highest score that can be achieved on that test. In other words, because the test has a limited number of difficult items, the most highly functioning individuals will score at the highest possible score. This becomes a measurement problem when you are trying to identify changes - the person may continue to improve but the test does not capture that improvement. Example: A memory test that assesses how many words a participant can recall has a total of five words that each participant is asked to remember. Because most individuals can remember all five words, this measure has a ceiling effect. See also "floor effect." More when using the NBI-LCVA scale.

Reliability

Internal consistencyA method of measuring reliability . Internal consistency reflects the extent to which items of a test measure various aspects of the same characteristic and nothing else. Internal consistency coefficients can take on values from 0 to 1. Higher values represent higher levels of internal consistency. More:
Arnadottir (1990) investigated the internal consistencyA method of measuring reliability . Internal consistency reflects the extent to which items of a test measure various aspects of the same characteristic and nothing else. Internal consistency coefficients can take on values from 0 to 1. Higher values represent higher levels of internal consistency. More of the A-ONE and reported adequate internal consistencyA method of measuring reliability . Internal consistency reflects the extent to which items of a test measure various aspects of the same characteristic and nothing else. Internal consistency coefficients can take on values from 0 to 1. Higher values represent higher levels of internal consistency. More of the ADL scale (α= 0.75 – 0.79), poor to adequate internal consistencyA method of measuring reliability . Internal consistency reflects the extent to which items of a test measure various aspects of the same characteristic and nothing else. Internal consistency coefficients can take on values from 0 to 1. Higher values represent higher levels of internal consistency. More of the NBSIS scale (α= 0.69 – 0.75), and poor internal consistencyA method of measuring reliability . Internal consistency reflects the extent to which items of a test measure various aspects of the same characteristic and nothing else. Internal consistency coefficients can take on values from 0 to 1. Higher values represent higher levels of internal consistency. More of the NBPIS scale (α= 0.59 – 0.63).

Arnadottir et al. (2008) examined the reliabilityReliability can be defined in a variety of ways. It is generally understood to be the extent to which a measure is stable or consistent and produces similar results when administered repeatedly. A more technical definition of reliability is that it is the proportion of “true” variation in scores derived from a particular measure. The total variation in any given score may be thought of as consisting of true variation (the variation of interest) and error variation (which includes random error as well as systematic error). True variation is that variation which actually reflects differences in the construct under study, e.g., the actual severity of neurological impairment. Random error refers to “noise” in the scores due to chance factors, e.g., a loud noise distracts a patient thus affecting his performance, which, in turn, affects the score. Systematic error refers to bias that influences scores in a specific direction in a fairly consistent way, e.g., one neurologist in a group tends to rate all patients as being more disabled than do other neurologists in the group. There are many variations on the measurement of reliability including alternate-forms, internal consistency , inter-rater agreement , intra-rater agreement , and test-retest .
of the ADL scale by performing a Rasch analysisRasch analysis is a statistical measurement method that allows the measurement of an attribute – such as upper limb function – independently of particular tests or indices.   It creates a linear representation using many individual items, ranked by item difficulty (e.g. picking up a very small item, versus a task requiring a very gross grasp) and person ability.   A well performing Rasch model will have items hierarchically placed from simple to more difficult, and individuals with high abilities should be able to perform all the items below a level of difficulty.  The Rasch model is statistically strong because it enables ordinal measures to be converted into meaningful interval measures. It also allows information from various tests or tools with different scoring systems to be applied using the Rasch model.
with retrospective data from 209 patients with neurological conditions (dementia, n=111; CVA, n=95, other, n=3). Item separation reliabilityReliability can be defined in a variety of ways. It is generally understood to be the extent to which a measure is stable or consistent and produces similar results when administered repeatedly. A more technical definition of reliability is that it is the proportion of “true” variation in scores derived from a particular measure. The total variation in any given score may be thought of as consisting of true variation (the variation of interest) and error variation (which includes random error as well as systematic error). True variation is that variation which actually reflects differences in the construct under study, e.g., the actual severity of neurological impairment. Random error refers to “noise” in the scores due to chance factors, e.g., a loud noise distracts a patient thus affecting his performance, which, in turn, affects the score. Systematic error refers to bias that influences scores in a specific direction in a fairly consistent way, e.g., one neurologist in a group tends to rate all patients as being more disabled than do other neurologists in the group. There are many variations on the measurement of reliability including alternate-forms, internal consistency , inter-rater agreement , intra-rater agreement , and test-retest .
was 0.98 and the item separation index was 8.02, indicating reliable differentiation of items into at least 9 strata of difficulty. A separation reliabilityReliability can be defined in a variety of ways. It is generally understood to be the extent to which a measure is stable or consistent and produces similar results when administered repeatedly. A more technical definition of reliability is that it is the proportion of “true” variation in scores derived from a particular measure. The total variation in any given score may be thought of as consisting of true variation (the variation of interest) and error variation (which includes random error as well as systematic error). True variation is that variation which actually reflects differences in the construct under study, e.g., the actual severity of neurological impairment. Random error refers to “noise” in the scores due to chance factors, e.g., a loud noise distracts a patient thus affecting his performance, which, in turn, affects the score. Systematic error refers to bias that influences scores in a specific direction in a fairly consistent way, e.g., one neurologist in a group tends to rate all patients as being more disabled than do other neurologists in the group. There are many variations on the measurement of reliability including alternate-forms, internal consistency , inter-rater agreement , intra-rater agreement , and test-retest .
coefficient of 0.90 and person separation index of 2.93 was found, indicating reliable differentiation of the sample into at least 3 statistically distinct strata of ADL ability.
Note: Item separation reliabilityReliability can be defined in a variety of ways. It is generally understood to be the extent to which a measure is stable or consistent and produces similar results when administered repeatedly. A more technical definition of reliability is that it is the proportion of “true” variation in scores derived from a particular measure. The total variation in any given score may be thought of as consisting of true variation (the variation of interest) and error variation (which includes random error as well as systematic error). True variation is that variation which actually reflects differences in the construct under study, e.g., the actual severity of neurological impairment. Random error refers to “noise” in the scores due to chance factors, e.g., a loud noise distracts a patient thus affecting his performance, which, in turn, affects the score. Systematic error refers to bias that influences scores in a specific direction in a fairly consistent way, e.g., one neurologist in a group tends to rate all patients as being more disabled than do other neurologists in the group. There are many variations on the measurement of reliability including alternate-forms, internal consistency , inter-rater agreement , intra-rater agreement , and test-retest .
is the ratio of the “true” (observed minus error) variance to the obtained variation. The smaller the error, the higher the ratio will be. It ranges from 0.00 to 1.00 and is interpreted the same as the Cronbach’s alpha. A separation index > 2.00 is equivalent to a Cronbach’s alpha of 0.80 or greater (excellent).

Test-retest:
Gardarsdottir & Kaplan (2002) reported that one-week test-retest reliabilityA way of estimating the reliability of a scale in which individuals are administered the same scale on two different occasions and then the two scores are assessed for consistency. This method of evaluating reliability is appropriate only if the phenomenon that the scale measures is known to be stable over the interval between assessments. If the phenomenon being measured fluctuates substantially over time, then the test-retest paradigm may significantly underestimate reliability. In using test-retest reliability, the investigator needs to take into account the possibility of practice effects, which can artificially inflate the estimate of reliability (National Multiple Sclerosis Society).
of the A-ONE was excellent (agreement of 0.85 or higher for all items).

Intra-rater:
No studies have reported on intra-rater reliabilityThis is a type of reliability assessment in which the same assessment is completed by the same rater on two or more occasions. These different ratings are then compared, generally by means of correlation. Since the same individual is completing both assessments, the rater's subsequent ratings are contaminated by knowledge of earlier ratings.
of the A-ONE.

Inter-rater:
Arnadottir (1990) reported excellent inter-rater reliabilityA method of measuring reliability . Inter-rater reliability determines the extent to which two or more raters obtain the same result when using the same instrument to measure a concept.
for the A-ONE ADL scale (average kappa coefficient = 0.83) and the NB scale (kappa = 0.85).

Further analysis by Arnadottir (2008) reiterated excellent inter-rater reliabilityA method of measuring reliability . Inter-rater reliability determines the extent to which two or more raters obtain the same result when using the same instrument to measure a concept.
for the A-ONE ADL scale (ICC=0.98; Kendall’s r=0.92, weighted kappa=0.90) and the NBSIS scale (ICC=0.93, weighted kappa=0.74).

Validity

Content:
Internal validation of the A-ONE was performed by examination of goodness of fit for items, logical hierarchical ordering of items, targeting, and PCA analysis (Arnadottir, 2010).

Arnadottir et al. (2008) performed factor analysis of the A-ONE ADL scale using retrospective data from 209 patients with neurological conditions (CVA, n= 95; dementia, n= 111, other diagnosis, n=3). Analysis of all 22 ADL items revealed that the two communication items (expression, comprehension) and one feeding item (‘use knife’) did not demonstrate acceptable goodness of fit (total of 13.6% item misfit). Following removal of the two communication items, the item ‘use knife’ demonstrated substantially reduced misfit to an acceptable rate (≤ 5%), and as such was maintained. With removal of the two communication items, 84% of total variance was explained by the measures, with 3.6% of the unexplained variance accounted for by first contrast. These results support unidimensionality of the ADL scale.

Arnadottir et al. (2009) performed factor analysis of nomotor neurobehavioural items (34 NBSIS items and 16 NBPIS items) using retrospective data from 206 patients with CVA and dementia. After four items (anomia, expressive aphasiaAphasia is an acquired disorder caused by an injury to the brain and affects a person’s ability to communicate. It is most often the result of stroke or head injury.
An individual with aphasia may experience difficulty expressing themselves when speaking, difficulty understanding the speech of others, and difficulty reading and writing. Sadly, aphasia can mask a person’s intelligence and ability to communicate feelings, thoughts and emotions. (The Aphasia Institute, Canada), working memoryExecutive process responsible for the temporary storage and manipulation of information in both simple (e.g. recalling a series of digits such as a phone number) and complex cognitive tasks (e.g. coordinating two tasks simultaneously) (Van der Linden, 2007)
, motivation) were removed due to outfit misfit, 56.8% of variance was explained by the Rasch factor (global measure of neurobehavioural impairments), with 4.9% of the unexplained variance accounted for by the first contrast. These results indicate that the neurobehavioural impairment items can be viewed as unidimensional – i.e. belonging to the same construct. The authors proceeded to conduct a principal component analysis (PCA) of global hierarchies according to diagnosis (LCVA, n=36; RCVA, n=37; dementia, n=111). After removal of misfit items (LCVA group – 2 items; RCVA and dementia groups – 3 items), improved results were seen for all diagnostic groups (Rasch factors: LCVA group = 85.5%, RCVA group = 83.3%, dementia group = 79.2%; unexplained variance in first contrast: LCVA group = 2.4%, RCVA group = 3.4%, dementia group = 1.7%). These results indicate that the hierarchical structure of the dimension varies across diagnostic groups.

Arnadottir (2010) reported on factor analysis conducted in development of the NBI common short form scale. All diagnosis-specific versions of the NBI scales demonstrate unidimensionality, as confirmed by PCA analysis (Arnadottir, 2010). The original NBSIS scale included neurobehavioural motor items that measured left- and right-sided performance, which were collapsed to a singular motor item. A resulting 33 neurobehavoural motor items were common to all 4 diagnostic groups (LCVA, RCVA, Dementia Alzheimers type, Dementia). Four of the 33 items were omitted due to misfit by Rasch analysisRasch analysis is a statistical measurement method that allows the measurement of an attribute – such as upper limb function – independently of particular tests or indices.   It creates a linear representation using many individual items, ranked by item difficulty (e.g. picking up a very small item, versus a task requiring a very gross grasp) and person ability.   A well performing Rasch model will have items hierarchically placed from simple to more difficult, and individuals with high abilities should be able to perform all the items below a level of difficulty.  The Rasch model is statistically strong because it enables ordinal measures to be converted into meaningful interval measures. It also allows information from various tests or tools with different scoring systems to be applied using the Rasch model.
and the remaining 29 items demonstrated acceptable goodness of fit. PCA analysis revealed 72.8% of variance was explained by Rasch factor, supporting unidimensionality.

Arnadottir et al. (2008) examined the hierarchical ordering of difficulty of ADL items using retrospective data from individuals with dementia (n=111), CVA (n=95), or other neurological conditions (n=3) and reported logical ordering according to item difficulty. However, Arnadottir (2010) conducted an evaluation of the targeting of person ability to item difficulty and identified that the ADL scale may not be well targeted to higher functioning individuals (discrepancy between mean measures = 1.61 logits).

Arnadottir (2010) reported that some NBI scales have large gaps in the hierarchy of item difficulty as there are few items that evaluate neurobehavioural impairments of higher-functioning individuals (mean person measure = -1.74, SD = 1.34).

Arnadottir et al. (2010) examined the relationship between ADL ability and the impact of neurobehavioural impairments on ADL using retrospective data from 215 patients with strokeAlso called a “brain attack” and happens when brain cells die because of inadequate blood flow. 20% of cases are a hemorrhage in the brain caused by a rupture or leakage from a blood vessel. 80% of cases are also know as a “schemic stroke”, or the formation of a blood clot in a vessel supplying blood to the brain. More. A moderate inverse relationship was found between ADL ability and the extent of neurobehavioural impairment impacting ADL, using Pearson product moment correlationThe most commonly used method of computing a correlation coefficient between variables that are linearly related. Pearson’s r is a measure of association which varies from -1 to +1, with 0 indicating no relationship (random pairing of values) and 1 indicating perfect relationship
(r=-0.57).

Arnadottir (2010) reported that the NBI-CVA scale demonstrates acceptable goodness of fit statistics for all retained items (MnSq ≤1.4, z < 2) and acceptable PCA.

Criterion:
Concurrent:
Steultjens (1998) examined the concurrent validityTo validate a new measure, the results of the measure are compared to the results of the gold standard obtained at approximately the same point in time (concurrently), so they both reflect the same construct. This approach is useful in situations when a new or untested tool is potentially more efficient, easier to administer, more practical, or safer than another more established method and is being proposed as an alternative instrument. See also “gold standard.”
of the A-ONE. Comparison of the A-ONE ADL scale with the Barthel Index and comparison of NB scores with the MMSE revealed excellent correlations (r=0.70 and r=0.85 respectively).

Predictive:
No studies have reported on the predictive validityA form of criterion validity that examines a measure’s ability to predict some subsequent event. Example: can the Berg Balance Scale predict falls over the following 6 weeks? The criterion standard in this example would be whether the patient fell over the next 6 weeks.
of the A-ONE.

Construct:
Convergent/Discriminant:
No studies have reported on the convergent or discriminant validityMeasures that should not be related are not. Discriminant validity examines the extent to which a measure correlates with measures of attributes that are different from the attribute the measure is intended to assess.
of the A-ONE.

Arnadottir (1990) conducted exploratory factor analysis and reported that the ADL scale has 3 factors and the NBSIS scale has 2 factors.

Arnadottir et al. (2009) performance factor analysis of the A-ONE neurobehavioural items and reported an additional factor is formed by neurobehavioural impairments that reflect occupational errors representative of lateralized motor impairments (e.g. tone).

Known Group:
Arnadottir et al. (2010) examined whether patients with right or left CVA differ in the extent to which their neurobehavioural impairments impact performance of ADLs, using retrospective data from 215 patients with strokeAlso called a "brain attack" and happens when brain cells die because of inadequate blood flow. 20% of cases are a hemorrhage in the brain caused by a rupture or leakage from a blood vessel. 80% of cases are also know as a "schemic stroke", or the formation of a blood clot in a vessel supplying blood to the brain. More. No significant difference in the extent of the impact of neurobehavioural impairment on ADL was seen between patients with right CVA (n=103) and patients with left CVA (n=112).

Gardarsdottir & Kaplan (2002) examined the construct validityReflects the ability of an instrument to measure an abstract concept, or construct. For some attributes, no gold standard exists. In the absence of a gold standard , construct validation occurs, where theories about the attribute of interest are formed, and then the extent to which the measure under investigation provides results that are consistent with these theories are assessed.
of the A-ONE ADL scale and Neurobehavioural Specific Impairment Scale (NBSIS) in adults with right CVA (n=19) and left CVA (n=23). Mann-Whitney U tests identified significant differences between the groups for only 3 of 18 ADL tasks: shave/makeup (p=0.013), comprehension (p=0.005), and speech (p=0.001), whereby patients with left CVA were more dependent than patients with right CVA for these tasks. Mann-Whitney U and chi-square tests revealed significant between-group differences for 13 of 46 neurobehavioural impairments, all within the three NSIS categories of motor apraxia, unilateral body neglect and abnormal tone. Results indicated that patients with left CVA demonstrated greater severity of motor apraxia in dressing (p=0.022), grooming and hygiene (p=0.001) and feeding (p=0.002) than patients with right CVA. Patients with left CVA also demonstrated greater severity of abnormal tone on both sides of the body in grooming and hygiene tasks (p=0.001) than patients with right CVA, whereas patient with right CVA demonstrated greater severity of abnormal tone on both sides of the body during performance of dressing (p=0.001), transfers and mobility (p=0.001) and feeding (p=0.001). Patients with right CVA also demonstrated greater severity of unilateral body neglect in grooming and hygiene tasks (p=0.002) than patients with left CVA.

Responsiveness

Principal component analysis of the ADL domain supported unidimensionality, enabling conversion of the ordinal rating scale to an interval scale, which would allow measurement of change in ADL task performance over time (Arnadottir, 1990).

References

• Arnadottir, G. (2010). Measuring the impact of body functions on occupational performance: Validation of the ADL-focused Occupation-based Neurobehavioural Evaluation (A-ONE). (Doctoral dissertation). Retrieved from Swedish Dissertations database.
• Arnadottir, G. (1990). The brain and behavior: Assessing cortical dysfunction through activities of daily living. St. Louis, MO: Mosby.
• Arnadottir, G. & Fisher, A.G. (2008). Rasch analysis of the ADL scale of the A-ONE. The American Journal of Occupational Therapy, 62, 51-60
• Arnadottir, G., Fisher, A.G., & Löfgren, B. (2009). Dimensionality of nonmotor neurobehavioural impairments when observed in the natural contexts of ADL task performance. Neurorehabilitation and Neural Repair, 23(6), 579-86.
• Arnadottir, G., Löfgren, B., & Fisher, A.G. (2010). Difference in impact of neurobehavioural dysfunction on activities of daily living performance between right and left hemisphere stroke. Journal of Rehabilitation Medicine, 42, 903-7.
• Bottari, C., Dutil, É., Dassa, C., & Rainville, C. (2006). Choosing the most appropriate environment to evaluation independence in everyday activities: Home or clinic? Australian Occupational Therapy Journal, 53, 98-106.
• Carswell, A., Carson, L.J., Walop, W. & Zgola, J. (1992). A theoretical model of functional performance in persons with Alzheimer disease. Canadian Journal of Occupational Therapy, 59(3), 132-40.
• Cooke, D.M., McKenna, K. & Fleming, J. (2005). Development of a standardized occupational therapy screening tool for visual perception in adults. Scandinavian Journal of Occupational Therapy, 12, 59-71.
• Gardarsdottir, S. & Kaplan, S. (2002). Validity of the Árnadottir OT-ADL Neurobehavioral Evaluation (A-ONE): Performance in activities of daily living and neurobehavioural impairments of persons with left and right hemisphere damage. American Journal of Occupational Therapy, 56, 499-508.
• Steultjens, E.M. (1998). A-ONE: De Nederlands Versie [A-ONE: The Dutch version]. Nederlands Tidskrift for Ergoterapie, 26, 100-4.

See the measure

How to obtain the assessment?

The A-ONE assessment is in the textbook: The Brain and Behavior: Assessing Cortical Dysfunction Through ActivitiesAs defined by the International Classification of Functioning, Disability and Health, activity is the performance of a task or action by an individual. Activity limitations are difficulties in performance of activities. These are also referred to as function.
of Daily Living.

For more information email: a-one@islandia.is