Psychometric evaluation of the disabilities of the arm, shoulder and hand (DASH) in patients with orthopedic shoulder impairments seeking outpatient rehabilitation.
J Hand Ther 2021;
34:404-414. [PMID:
32291118 DOI:
10.1016/j.jht.2020.01.002]
[Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 01/09/2020] [Accepted: 01/12/2020] [Indexed: 02/03/2023]
Abstract
STUDY DESIGN
This is a cross-sectional, observational study.
INTRODUCTION
The disability of the arm, shoulder and hand (DASH) questionnaire is an upper-extremity specific outcome measure commonly used in routine clinical care and clinical trials.
PURPOSE OF THE STUDY
Our purposes were to: (1) examine the psychometric properties of the DASH questionnaire using factor analysis, one- and two-parameter item response theory models, and (2) develop a functional staging map illustrating the relationships between the item difficulty hierarchy of the DASH items and the patient's DASH total score.
METHODS
Data from 2724 patients with orthopedic shoulder impairments seeking outpatient physical therapy in 79 clinics in the US were analyzed.
RESULTS
Factor analysis supported a general factor, explaining 62.2% of the total variance. The coverage of DASH items was suitable for patients with shoulder impairments with no ceiling or floor effect. Endorsed items representing the most difficult items were related to feeling less capable, executing recreational activities with force or impact, and performing recreational activities in which you move your arm freely. Items with higher discriminating abilities were those related to do heavy household chores, garden/yard work, and change a light bulb overhead. With a separation index equaled to 4.94, the DASH can differentiate persons into at least 6 statistically distinct person strata. None of the DASH items exhibited differential item functioning by gender or symptom acuity, except two items by age group.
DISCUSSION
Besides a total (summed) final score obtained from a specific measure, the keyform and functional staging plots/maps can be used to assist clinicians in clinical interpretation of the scores.
CONCLUSIONS
Results supported the clinical usage of the DASH questionnaire in patients with orthopedic shoulder impairments seeking outpatient rehabilitation.
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