Abstract
BackgroundThis study investigated the ArmA-TH sub-scale measurement properties based on item response theory using the Rasch model.MethodsPatients with upper limb hemiplegia resulting from cerebrovascular and other brain disorders were asked to complete the ArmA-TH questionnaire. Rasch analysis was performed to test how well the ArmA-TH passive and active function sub-scales fit the Rasch model by investigating unidimensionality, response category functioning, reliability of person and item, and differential item functioning (DIF) for age, sex, and education.ResultsParticipants had stroke or other acquired brain injury (n = 185), and the majority were men (126, 68.1 %), with a mean age of 55 (SD 22). Most patients (91, 49.2 %) had graduated from elementary/primary school. For the ArmA-TH passive function scale, all items had acceptable fit statistics. The scale’s unidimensionality and local independence were supported. The reliability was acceptable. A disordered threshold was found for five items, and none indicated DIF. For the ArmA-TH active function scale, one item was misfit and three were locally dependent. The reliability was good. No items showed DIF. All items had disordered thresholds, and the data fitted the Rasch model better after rescoring.ConclusionsBoth sub-scales of ArmA-TH fitted the Rasch model and were valid and reliable. The disordered thresholds should be further investigated.
Highlights
This study investigated the Arm Activity Measure questionnaire (ArmA)-TH sub-scale measurement properties based on item response theory using the Rasch model
As there has never been an objective self-report measure for assessing hemiparetic upper limb function for patients in Thailand, ArmA was translated into the Thai language as Arm Activity Measure Thai version (ArmA-TH) with a preliminary evaluation of psychometric properties, including a content validity index for both item (I-CVI) and score (S-CVI), interrater reliability, and internal consistency [3]
Neither the construct validity of the items nor a detailed item evaluation of ArmA-TH based on measurement theory were initially explored
Summary
This study investigated the ArmA-TH sub-scale measurement properties based on item response theory using the Rasch model. According to Rasch measurement theory, an outcome measure scale should demonstrate unidimensionality (all items contribute to the same construct) and have no DIF (invariance across a sub-population) [4]. All these properties can be evaluated by conformity to the Rasch model, which the original English version of the ArmA passive function sub-scale was evaluated against in a UK sample [5]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
