Rasch Analysis of the Assessment of Quality of Activities (A-QOA), an Observational Tool for Clients With Dementia.

Abstract

IMPORTANCE\nThe Assessment of Quality of Activities (A-QOA) is an observation-based tool for assessing the strength of engagement in an activity by the person performing it in a natural context. By quantifying the quality of engagement, the A-QOA can help occupational therapy practitioners be better able to select meaningful activities and more clearly understand the effectiveness of various choices.\n\n\nOBJECTIVE\nTo examine use of the A-QOA as a valid unidimensional scale and to clarify preliminary results on its internal scale validity and item reliability using the Rasch model.\n\n\nPARTICIPANTS\nOne hundred thirty-one participants with dementia performing 262 activities.\n\n\nOUTCOMES AND MEASURES\nWe used the Rasch model to clarify the psychometric properties of A-QOA s measurement quality.\n\n\nRESULTS\nRasch analysis revealed that 21 of the 25 items reached an acceptable level of fit, and 4 did not. After eliminating the 4 misfitting items, the resulting A-QOA was determined to have both acceptable internal scale validity and item separation reliability, which are fundamental psychometric properties of a clinical observational instrument.\n\n\nCONCLUSIONS AND RELEVANCE\nThe A-QOA can be used to quantitatively assess the strength of engagement in an activity by the person performing it by using the observational method.\n\n\nWHAT THIS ARTICLE ADDS\nIn clinical settings, the A-QOA can be used both to select activities for clients with dementia and to quantitatively show the effects of occupational therapy interventions.