Open AccessConstruct Validity of the Test of Visual-Motor Integration: An Evaluation Using Rasch Analysis
Author(s) -
Ted Brown,
Carolyn A. Unsworth
Publication year - 2009
Publication title -
hong kong journal of occupational therapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.301
H-Index - 13
eISSN - 1876-4398
pISSN - 1569-1861
DOI - 10.1016/s1569-1861(09)70038-5
Subject(s) - rasch model , construct validity , psychology , construct (python library) , test (biology) , polytomous rasch model , test validity , cognitive psychology , psychometrics , applied psychology , physical medicine and rehabilitation , item response theory , developmental psychology , computer science , medicine , paleontology , biology , programming language
BackgroundRasch analysis can be used as a method of evaluating construct validity during test construction, validation, or evaluation.ObjectiveThe aim of this study was to examine the construct validity of the Test of Visual-Motor Integration (TVMI) by applying Rasch analysis to evaluate its scalability, dimensionality, differential item functioning (DIF), hierarchical ordering, and scoring category structure.MethodsThe participants included 400 children aged 5–12 years, recruited from six schools in the Melbourne metropolitan area, Victoria, Australia. The children completed the TVMI under the supervision of an occupational therapist.ResultsOverall, 3 of 30 of the TVMI scale items were problematic: Items 1 and 2 exhibited a Rasch model misfit and Item 5 exhibited DIF based on gender. In addition, the TVMI items were not found to be hierarchically ordered as reported in its manual. The TVMI scoring category structure was satisfactory.ConclusionBecause only three TVMI items were found to be problematic, the construct validity of the TVMI appears satisfactory. However, given that the items are not hierarchically ordered, it is recommended that clinicians use the TVMI with caution when calculating participants' performance scores. This is particularly relevant if testing is ceased if a participant reaches the TVMI ceiling point by drawing three items incorrectly in a row