Occupational Therapy Adult Perceptual Screening Test (OT-APST)

Evidence Reviewed as of before: 19-08-2008
Author(s): Lisa Zeltzer, MSc OT
Editor(s): Nicol Korner-Bitensky, PhD OT; Elissa Sitcoff, BA BSc

Purpose

The Occupational Therapy Adult Perceptual Screening Test (OT-APST) is a standardized screening 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 stroke.

In-Depth Review

Purpose of the measure

The Occupational Therapy Adult Perceptual Screening Test (OT-APST) is a standardized screening 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 stroke.

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 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 activities 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 subscale, 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 stroke.

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 participation 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 stroke
Is this a screening or assessment tool? Screening
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
Reliability
  • Only 1 study has examined the internal consistency of the OT-APST and reported adequate to excellent levels of internal consistency.
  • Only 1 study has examined the test-rest reliability of the OT-APST, and reported excellent test-retest.
  • Only 1 study has examined the inter-rater reliability of the OT-APST and reported adequate to excellent inter-rater reliability.
  • – Only 1 study has examined the intra-rater reliability of the OT-APST and reported adequate to excellent intra-rater reliability.
Validity

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 subscale and the corresponding Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) or LOTCA-Geriatric version (LOTCA-G) subscale. 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:

OT-APST can differentiate between patients with stroke 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 participation 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 consistency:
Cooke, McKenna, Fleming, Darnell (2006a) examined the internal consistency of the OT-APST subscales Agnosia, Body scheme, Neglect, and Constructional skills in 208 participants with stroke. The internal consistency alpha coefficients for these subscales ranged between 0.71 and 0.83, indicating adequate to excellent levels of internal consistency.

Test-retest:
Cooke, McKenna, Fleming, and Darnell (2005b) examined the test-retest reliability of the OT-APST by having one rater administer and score the OT-APST to 15 patients with stroke 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 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 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 reliability of the OT-APST by having 9 occupational therapy raters each score 5 patients with stroke 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 reliability 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 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 validity of the OT-APST in 208 patients with stroke 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 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 validity of the OT-APST by comparing the subscales of the OT-APST to the corresponding subscale 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 subscale of the OT-APST and the corresponding subscale 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 validity of the OT-APST with the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) in 208 people with stroke 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 validity 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 stroke 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 subscale 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 stroke and healthy control participants. The patients with stroke 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 stroke participant group for 56.7% of participants with stroke. The inverse figures for these comparisons are that 5.9% of the healthy participants were predicted to be members of the stroke group (predicted to have perceptual impairments), and 43.3% of participants following stroke 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/.

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