Convergent validity of the Occupational Therapy Adult Perceptual Screening Test (OT-APST) with two other cognitive-perceptual tools in a South African context

Abstract

Background and aim: Occupational therapists working in the field of neuro-rehabilitation need to use screening tools which demonstrate validity and reliability to correctly identify patients with cognitive-perceptual impairments. The Occupational Therapy Adult Perceptual Screening Test (OT-APST) is a screening tool which was developed to identify patients with visual perceptual problems and apraxia following a stroke or other forms of acquired brain injury. Other instruments available are the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) and the Rivermead Perceptual Assessment Battery (RPAB). These tools evaluate similar constructs such as visual agnosia, body scheme, unilateral neglect and constructional skills but are too lengthy to use as screening tools.

The aim of the study was to determine the convergent validity of the OT-APST with two other cognitive-perceptual tools commonly used in South Africa, namely the Dynamic Occupational Therapy Cognitive Assessment (DLOTCA)  and the RPAB when administered to patients with a primary diagnosis of stroke.

Method: A quantitative cross-sectional study was conducted on a sample of 32 participants with a primary diagnosis of stroke. Participants completed the three tools and subscales were compared with the Dynamic Loewenstein Occupational Therapy Cognitive Assessment (DLOTCA) cognitive areas and the RPAB items.

Results: Five subscales of the OT-APST had significant correlations with similar DLOTCA and/or the RPAB subscales. Only the Apraxia subscale did not correlate with the referencing tools.

Conclusion: This study provides further evidence of the convergent validity of the OT-APST when compared to the DLOTCA and RPAB. Although the OT-APST was standardised on an Australian population, it proved to be another option of a visual perceptual screening tool to identifying visual perceptual problems in patients with stroke in South Africa.

Key words: Cognitive-perceptual, Stroke, convergent validity, Occupational therapy Adult Perceptual Screening Test (OT-APST), Dynamic Occupational Therapy Cognitive Assessment (DLOTCA), Rivermead Perceptual Assessment Battery (RPAB).