Background: There is a lack of occupation-focused instruments to assess Activities of Daily Living (ADL) that are intended for persons with mental disorders. The ADL Taxonomy is an instrument that is widely-used within clinical practice for persons with physical impairment. The aim of this study was to adapt the ADL Taxonomy for persons with mental disorders and evaluate its validity.
Methods: An expert group of Occupational Therapists (OTs) from psychiatric care adapted the ADL Taxonomy to fit the client group, including creating three new items. OTs in psychiatric care collected client data and evaluated the instrument for usability. Rasch analysis was used to evaluate the contruct validity of 16 activities separately.
Results: The OTs collected 123 assessments from clients with various mental disorders. Ten activities had excellent, and four had acceptable, psychometric properties with regard to item and person fit and unidimensionality. The activity managing the day/time gave complex results and would benefit from further development. The OTs found the test version intelligible, relevant and easy to use.
Conclusions: The ADL Taxonomy for persons with mental disorders has 16 activities with three to six actions each, and is now ready for clinical use.
Keywords: Activities of daily living; assessment; occupational therapy; psychometric properties; rasch analysis.