An Examination of the Construct Validity of the Motor-Free Visual Perceptual Test—Third Edition (MVPT-3) Using Rasch Analysis with Adult Participants

Abstract

Visual perceptual skills of adults are often assessed by occupational therapists using standardized tests. The Motor-Free Visual Perception Test—Third Edition (MVPT-3) is a frequently used test, although its construct validity has not been thoroughly evaluated. The purpose of the study was to consider the construct validity of the MVPT-3 by evaluating its scalability/interval level measurement, unidimensionality, lack of differential item functioning (DIF), and hierarchical ordering of its items when completed by a group of adult participants. The visual perceptual performance scores from a sample of 221 participants 20 years or older (49 adults with neurological impairment and 172 adults without) were used to complete a Rasch analysis (RA) of the MVPT-3. When analyzed using RA, the MVPT-3 exhibited adequate measurement properties. However, several MVPT-3 scales exhibited RA misfit (items 40, 45, 54, 56, 61, 64) or DIF (items 57, 60, 61). The construct validity, scalability, unidimensionality, hierarchical ordering, and lack of DIF requirements were met by most (87.7%; 8 of 65 items) of the MVPT-3 scale items. When using the MVPT-3 to assess adult clients, clinicians should consider the items that exhibited RA misfit or DIF when interpreting scores.