Occupational Therapy Adult Perceptual Screening Test (OT-APST)

Purpose

The Occupational Therapy Adult Perceptual ScreeningTesting for disease in people without symptoms.
Test (OT-APST) is a standardized screeningTesting for disease in people without symptoms.
measure that enables occupational therapists to test for the presence of impairment in visual perception across each of the major constructs of visual perception and praxis, including the problems most frequently occurring after 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..

In-Depth Review

Purpose of the measure

The Occupational Therapy Adult Perceptual ScreeningTesting for disease in people without symptoms.
Test (OT-APST) is a standardized screeningTesting for disease in people without symptoms.
measure that enables occupational therapists to test for the presence of impairment in visual perception across each of the major constructs of visual perception and praxis, including the problems most frequently occurring after 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..

Available versions

The OT-APST was developed by Deidre M. Cooke in 1992 and was first published in 1993 (Cooke, 1993). The OT-APST was revised in 2001.

Features of the measure

Items:

The OT-APST has 25 items in 7 subtest areas (Agnosia; Visuospatial Relations – Unilateral neglect and Body scheme -; Constructional skills; Apraxia; Acalculia; Functional Skills). Several of the items contribute to assessment of more than one area and are only performed once. The subtests and their respective items are organized as follows:

Agnosias (5 items)

• Colour agnosia: The client is requested to name/identify six colors in an array to evaluate color recognition skills.
• Object agnosia: The client is presented with a stapler that he/she must name and describe in terms of its use to demonstrate object recognition and naming.
• Figure-ground: The client must recognize five items in an overlapping array to demonstrate figure-ground/perceptual closure skills.
• Shape constancy: The client is presented with a mixed array of 10 shapes of varying sizes and positioned at different angles. The client must name/point on command to four common shapes to demonstrate shape recognition ability.
• Reading-alexia: The client is asked to read a passage of text that has indentations of random lengths on both sides of the page to be sensitive to attention/neglect changes to both the left and right side of space.

Visuospatial relations – Unilateral neglect and Body scheme

Unilateral neglect (5 items)

• Clock drawing
• Copying a house diagram
• Writing: The client is asked to provide a handwriting sample that consists of writing their name and address.
• Reading a paragraph: The client is asked to read a passage of 12 lines to assess reading and visual scanningDuring this intervention the person with USN is encouraged to conduct voluntary eye movements toward the neglected visual field (usually the left side) by performing a task in that hemispace. The treatment often includes a visual target that the patient uses as an anchor to direct voluntary gaze control while scanning.
  accuracy, to detect for the presence of neglect or the impact of visual field loss on reading, and to screen for alexia.
• Telling time

Body scheme (4 items)

• Body parts self: The client is asked to identify his/her own body parts.
• Body parts therapist: The client is asked to identify the examiner’s body parts.
• Left/right discrimination: The client is requested to differentiate sides (left and right).
• Directions/position in space: The client is asked to move colored blocks to different positions in relation to each other (e.g. ‘on top of’ or ‘behind’), or to describe the color or point to the block that is ‘furthest away’ from and ‘nearest’ to him/her on the tabletop.

Constructional skills (3 items):

• Graphic constructional skills: The client is asked to draw a clock and place its hands at a designated time. They must also copy a house.
• Two-dimensional construction: The client is asked to reproduce colored block patterns in two-dimensional planes by copying a model provided.
• Three-dimensional construction: Three-dimensional models rather than pictures of these models are copied.

Apraxia (6 items):

• Smile command and copy
• Wave right hand-command and copy
• Wave left hand-command and copy
• Stapler hold command and copy
• Pen use for writing
• Writing

Acalculia (1 item):

• The client is asked to perform simple one- and two-digit addition and subtraction calculations that are set at a grade two level.

Functional skills (5 items):

• Reading
• Writing
• Calculations: The client must complete simple mathematical calculations.
• Telling time
• Use of stapler

Futher observations of the client’s performance of other 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 such as dressing and grooming, in addition to performing a kitchen task are recommended but are not formally included in the OT-APST.

Other:

The length of time taken to complete the OT-APST in its entirety is recorded as a general indicator of the information-processing speed of the client and to reflect the client’s perceptual processing ability.

Scoring:

Scores for items in each construct or subtest area are summed to allow interpretation of patterns of impairments and to compare with normative data, but not to produce a total score for the OT-APST.

The table below outlines the subtest total scores and individual item scores of the OT-APST:

(Cooke, McKenna, Fleming, & Darnell, 2005a)

OT-APST subtests (subtest total score)	OT-APST items (item scores)
Agnosias (26)	Colour agnosia (6) Object agnosia (1) Figure-ground (5) Shape constancy (10) Reading-alexia (4)
Visuospatial relations:
Unilateral neglect (13)	Clock (3) House (4) Writing (1) Reading (4) Telling time (1)
Body scheme (22)	Body parts self (8) Body parts therapist (4) Left/right discrimination (4) Directions/position in space (6)
Constructional skills (53)	Graphic construction Clock (3) House (4) Two-dimensional construction (26) Three-dimensional construction (20)
Apraxia (10)	Smile command and copy (2) Wave right hand-command and copy (2) Wave left hand-command and copy (2) Stapler hold command and copy (2) Pen use for writing (1) Writing (1)
Acalculia (4)	Calculations-addition and subtraction (4)
Functional skills (11)	Reading (4) Writing (1) Calculations (4) Telling time (1) Use of stapler (1)

Cooke, McKenna, Fleming, and Darnell (2006c) examined the impact of age, education, and gender on OT-APST scoring based on the performance of 356 healthy Australian adults aged 16-97 years. When mean scores were compared for each 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).
, the most significant differences were observed with age. Gender and level of education did not significantly impact on OT-APST performance of the healthy participants. Increasing age was significantly associated with reduced performance on all subscales but the Acalculia and Body scheme subscales. The age at which the most significant differences in OT-APST performance occurred was at age 75 years and above.

The tables below provides the cutoff scores indicating impairment for each of the subscales of the OT-APST, stratified by age group:

(Cooke, McKenna, Fleming, & Darnell, 2006c)

Age 16-74 years cut-off scores indicative of impairment

Agnosia	Body scheme	Neglect	Constructional skills	Apraxia	Acalculia	Functional skills
≤ 24	≤ 21	≤ 12	≤ 51	≤ 9	≤ 2	≤ 9

Age 75-97 years cut-off scores indicative of impairment

Agnosia	Body scheme	Neglect	Constructional skills	Apraxia	Acalculia	Functional skills
≤ 22	≤ 20	≤ 10	≤ 46	≤ 8	≤ 2	≤ 9

Time:

The OT-APST can be administered within 20 to 25 minutes (Cooke, McKenna, & Fleming, 2005a).

Subscales:

The OT-APST has 7 subscales: Agnosia; Visuospatial Relations – Unilateral neglect and Body scheme -; Constructional skills; Apraxia; Acalculia; Functional Skills.

Equipment:

All of the equipment required for completion of the OT-APST is provided in the assessment kit that can be purchased online at: http://www.functionforlife.com.au/images/OT-APSTorderformA4.pdf

Training:

No formal training is required for the OT-APST. The manual provides standard directions for the administration and scoring of the measure.

Alternative forms of the OT-APST

None.

Client suitability

Can be used with:

• 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..

Should not be used with:

• Completion of the OT-APST requires adequate comprehension of simple verbal instructions.
• It is not suitable for individuals with severe auditory comprehension problems.
• It is not suitable for individuals who are unable to use either hand for task completion.
• The OT-APST is not suitable for individuals whose level of arousal or attentional capacity precludes participationAs defined by the International Classification of Functioning, Disability and Health, participation is an individual’s involvement in life situations in relation to health conditions, body functions or structures, activities, and contextual factors. Participation restrictions are problems an individual may have in the manner or extent of involvement in life situations. for the necessary time required for task completion.
• The OT-APST is not suitable for individuals with receptive language problems, however, alternative methods of test administration are included for clients with expressive language problems.

In what languages is the measure available?

To our knowledge based on a review of the scientific literature, the OT-APST has not been formally translated and validated in other languages.

Summary

What does the tool measure?	Impairment in visual perception
What types of clients can the tool be used for?	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.
Is this a screeningTesting for disease in people without symptoms. or assessment tool?	ScreeningTesting for disease in people without symptoms.
Time to administer	The OT-APST takes 20-25 minutes to administer.
Versions	There are no alternative versions of the OT-APST.
Other Languages	The OT-APST has not been formally translated and validated into other languages.
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.: Only one study has examined 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. of the OT-APST and reported adequate to excellent levels of 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.. Test-rest: Only one study has examined the test-rest 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 OT-APST, and reported excellent test-retest. Inter-rater: Only one study has examined the 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. of the OT-APST and reported adequate to 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. . Intra-rater: Only one study has examined the 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 OT-APST and reported adequate to excellent 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. .
ValidityThe degree to which an assessment measures what it is supposed to measure.	Criterion: Concurrent: Poor to excellent correlations with the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) and the LOTCA-Geriatric version (LOTCA-G) have been reported. Construct: Convergent: Poor to excellent correlations were reported between each OT-ASPT 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). and the corresponding Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) or LOTCA-Geriatric version (LOTCA-G) 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). . Adequate to excellent correlations were reported between the OT-APST and the LOTCA to patients under 70 years of age and between the OT-APST and on the LOTCA-G to patients over 70 years of age. Poor to adequate correlations were reported between OT-ASPT and the Functional Independence Measure (FIM). Known groups: L’OT-APST can differentiate between 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. and healthy controls.
Does the tool detect change in patients?	Not Applicable.
Acceptability	The OT-APST is not suitable for individuals: With severe auditory comprehension problems Who are unable to use either hand for task completion, Whose level of arousal/attentional capacity precludes participationAs defined by the International Classification of Functioning, Disability and Health, participation is an individual’s involvement in life situations in relation to health conditions, body functions or structures, activities, and contextual factors. Participation restrictions are problems an individual may have in the manner or extent of involvement in life situations. for the necessary time required for task completion With receptive language problems Alternative methods of test administration are provided for clients with expressive language problems.
Feasibility	The OT-APST takes 20-25 minutes to complete and does not require any formal training. The measure is simple to score and all required materials and instructions for administration are provided in the assessment kit that can be purchased. The OT-APST is simple to score.
How to obtain the tool?	The OT-APST Assessment Kit and forms can be purchased from OT Australia Qld by visiting the following website: http://www.otqld.org.au/docs/2008%20OT-APST%20order%20form.pdf or by visiting http://www.functionforlife.com.au/#research.

Psychometric Properties

Overview

We conducted a literature search to identify all relevant publications on the psychometric properties of the OT-APST. To our knowledge, the creators of the OT-APST have personally gathered the majority of psychometric data that are currently published on the 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.:
Cooke, McKenna, Fleming, Darnell (2006a) examined 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. of the OT-APST subscales Agnosia, Body scheme, Neglect, and Constructional skills in 208 participants 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.. 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. alpha coefficients for these subscales ranged between 0.71 and 0.83, indicating adequate to excellent levels of 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..

Test-retest:
Cooke, McKenna, Fleming, and Darnell (2005b) examined the 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 OT-APST by having one rater administer and score the OT-APST to 15 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. and videotape their performance. The same rater then assessed the same patients at the same time of day, 2 weeks later. On 14 of the 25 items, there was 100% agreement between the first and second assessments. For the 11 remaining items, the percentage agreement ranged between 70% and 90%, with the exception of one item, Two-dimensional Constructional skills, which had only 20% agreement. Intraclass correlationThe extent to which two or more variables are associated with one another. A correlation can be positive (as one variable increases, the other also increases – for example height and weight typically represent a positive correlation) or negative (as one variable increases, the other decreases – for example as the cost of gasoline goes higher, the number of miles driven decreases. There are a wide variety of methods for measuring correlation including: intraclass correlation coefficients (ICC), the Pearson product-moment correlation coefficient, and the Spearman rank-order correlation.
coefficients (ICCs) were calculated for 6 of the 13 items, where the percentage agreement was less than 100% and the scale of the item was appropriate for this form of correlationThe extent to which two or more variables are associated with one another. A correlation can be positive (as one variable increases, the other also increases – for example height and weight typically represent a positive correlation) or negative (as one variable increases, the other decreases – for example as the cost of gasoline goes higher, the number of miles driven decreases. There are a wide variety of methods for measuring correlation including: intraclass correlation coefficients (ICC), the Pearson product-moment correlation coefficient, and the Spearman rank-order correlation.
calculation. The ICCs were considered excellent, ranging from 0.76 to 0.95.

Intra-rater:
Cooke, McKenna, Fleming, and Darnell (2005b) examined the 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 OT-APST by having 9 occupational therapy raters each score 5 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. from video recordings. Following a time delay of 2 weeks, all of the raters viewed the videos again and scored the same five participants in a different randomized order. On 12 of the 25 items, there was 100% agreement between the scores for the first and second video scoring sessions. On the other 13 items, the percentage agreement for raters between the first and second scoring sessions ranged from 83% to 98%. ICCs ranged from adequate (ICC = 0.64) to excellent (ICC = 1.0).

Inter-rater:
Cooke, McKenna, Fleming, and Darnell (2005b) examined the 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.
of the OT-APST by having one rater administer and score the OT-APST to 15 patients with stroke and videotape their performance. Nine raters were then allocated to score 5 patients. Each video was scored by three separate raters and presented in random order to each rater. Intraclass correlationThe extent to which two or more variables are associated with one another. A correlation can be positive (as one variable increases, the other also increases - for example height and weight typically represent a positive correlation) or negative (as one variable increases, the other decreases - for example as the cost of gasoline goes higher, the number of miles driven decreases. There are a wide variety of methods for measuring correlation including: intraclass correlation coefficients (ICC), the Pearson product-moment correlation coefficient, and the Spearman rank-order correlation.
coefficients (ICCs) ranged from adequate (ICC = 0.66 for the Clock item) to excellent (ICC = 1.00 for the items Wave left hand-command and copy, and Two-dimensional Constructional skills). On 12 of the 25 items, there was 100% agreement between all raters and the original ratings given by one rater on 15 patients. On the other 13 items, the proportion of agreement between all raters and the original rater ranged between 83% and 99%.

Validity

Criterion:
Concurrent:
Cooke, McKenna, Fleming, Darnell (2006b) 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 OT-APST in 208 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. by comparing patient performance on the OT-APST with their performance on the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) and the LOTCA-Geriatric version (LOTCA-G). Somer’s d was used to calculate correlations between the measures. The OT-APST was found to have a poor to excellent correlationThe extent to which two or more variables are associated with one another. A correlation can be positive (as one variable increases, the other also increases – for example height and weight typically represent a positive correlation) or negative (as one variable increases, the other decreases – for example as the cost of gasoline goes higher, the number of miles driven decreases. There are a wide variety of methods for measuring correlation including: intraclass correlation coefficients (ICC), the Pearson product-moment correlation coefficient, and the Spearman rank-order correlation.
with the LOTCA (0.27-0.64) and with the LOTCA-G (0.25-0.80).

Construct:
Convergent:
Cooke, McKenna, Fleming, Darnell (2006a) examined the convergent validityA type of validity that is determined by hypothesizing and examining the overlap between two or more tests that presumably measure the same construct. In other words, convergent validity is used to evaluate the degree to which two or more measures that theoretically should be related to each other are, in fact, observed to be related to each other.
of the OT-APST by comparing the subscales of the OT-APST to the corresponding 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).
of the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) or the LOTCA-Geriatric version (LOTCA-G) using Spearman’s rho correlations. Statistically significant correlations were found between each 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).
of the OT-APST and the corresponding 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).
of the LOTCA or LOTCA-G. The highest correlations occurred for the subscales of Constructional skills and Neglect, with more moderate correlations occurring for subscales assessing Agnosia, Body scheme, and Apraxia. Correlations ranged from poor (0.33 for Apraxia) to excellent (0.80 for Constructional skills).

Similar to the study by Cooke et al. (2006a), Itzkovich, Elazar, Averbuch and Katz (2000) examined the convergent validityA type of validity that is determined by hypothesizing and examining the overlap between two or more tests that presumably measure the same construct. In other words, convergent validity is used to evaluate the degree to which two or more measures that theoretically should be related to each other are, in fact, observed to be related to each other.
of the OT-APST with the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) in 208 people 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. who were younger than 70 years of age. Adequate to excellent correlations were found between the OT-APST and on five of the related subscales of the reference tool of the LOTCA (r = 0.36 to r = 0.70).

Elazar, Itzkovich , and Katz (1996) examined the convergent validityA type of validity that is determined by hypothesizing and examining the overlap between two or more tests that presumably measure the same construct. In other words, convergent validity is used to evaluate the degree to which two or more measures that theoretically should be related to each other are, in fact, observed to be related to each other.
of the OT-APST with the Loewenstein Occupational Therapy Cognitive Assessment-Geriatric (LOTCA-G) version for those 70 years and over and found adequate to excellent correlations between the performance of elderly 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. on the OT-APST and on the LOTCA-G (r = 0.33 to r = 0.80).

Cooke, McKenna, Fleming, Darnell (2006a) examined whether the OT-APST correlated with the Functional Independence Measure (FIM). Significant correlations were observed between six of the seven OT-APST subscales and FIM motor scores. Spearman’s correlations ranged from poor to adequate (r = 0.26 to r = 0.41). Significant correlations were found between all seven OT-APST subscales and the FIM cognitive scores. Spearman’s correlations were adequate (r = 0.36 to r = 0.50). Significant negative correlations were also observed between the time taken by participants to complete the OT-APST and both FIM scores, indicating that more severe functional disability was associated with greater length of time to complete the OT-APST. Body scheme was the only OT-APST 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).
score not significantly correlated with FIM motor scores.

Known groups:
Cooke, McKenna, Fleming, Darnell (2006a) examined whether the OT-APST was able to discriminate between 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. and healthy control participants. The 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. performed significantly worse than the healthy participants on all 7 subscales of the OT-APST, and took significantly longer to complete the test. All t-tests and Mann-Whitney U tests comparing the two groups were significant at p < 0.001. The OT-APST was found to correctly predict membership of the healthy group for 94.1% of the healthy participants, and correctly predicted membership of the 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. participant group for 56.7% of participants 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.. The inverse figures for these comparisons are that 5.9% of the healthy participants were predicted to be members of the 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. group (predicted to have perceptual impairments), and 43.3% of participants following 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. were predicted to be members of the healthy group (no perceptual impairments).

Responsiveness

Not applicable.

References

• Cooke, D. (1993). Development and standardization of an apraxia assessment and perceptual screening test for the elderly. In: Australian Association of Occupational Therapists 17th National Conference Proceedings, 1993.
• Cooke, D. M., McKenna, K., Fleming, J. (2005a). Development of a standardized occupational therapy screening tool for visual perception in adults. Scandinavian Journal of Occupational Therapy, 12, 59-71.
• Cooke, D. M., McKenna, K., Fleming, J., Darnell, R. (2005b). The reliability of the Occupational Therapy Adult Perceptual Screening Test (OT-APST). British Journal of Occupational Therapy, 68(11), 509-517.
• Cooke, D. M., McKenna, K., Fleming, J., Darnell, R. (2006a). Construct and ecological validity of the Occupational Therapy Adult Perceptual Screening Test (OT-APST). Scandinavian Journal of Occupational Therapy. 13, 49- 61.
• Cooke, D. M., McKenna, K., Fleming, J., Darnell, R. (2006b). Criterion validity of the Occupational Therapy Adult Perceptual Screening Test (OT-APST). Scandinavian Journal of Occupational Therapy. 13, 38-48.
• Cooke, D. M., McKenna, K., Fleming, J., Darnell, R. (2006c). Australian normative data for the Occupational Therapy Adult Perceptual Screening Test. Australian Occupational Therapy, 53, 325-336.
• Itzkovich, M., Elazar, B., Averbuch, S., Katz, N.(2000). LOTCA manual (2nd ed.). Pequannock, NJ: Maddak Inc.
• Elazar, B., Itzkovich, M., Katz, N. (1996).Geriatric version: Loewenstein Occupational Therapy Cognitive Assessment (LOTCA-G) battery. Pequannock, NJ: Maddak Inc.

See the measure

How to obtain the OT-APST?

The OT-APST Assessment Kit and forms can be purchased from OT Australia Qld by visiting the following website: http://www.functionforlife.com.au/.