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

IMPORTANCE

The 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.

OBJECTIVE

To 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.

PARTICIPANTS

One hundred thirty-one participants with dementia performing 262 activities.

OUTCOMES AND MEASURES

We used the Rasch model to clarify the psychometric properties of A-QOA's measurement quality.

RESULTS

Rasch 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.

CONCLUSIONS AND RELEVANCE

The 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.

WHAT THIS ARTICLE ADDS

In 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.