Measuring confidence with manual wheelchair use : a four phase, mixed-methods study

Introduction Confidence in one’s ability to perform a given task can be a stronger predictor of performance than skill itself. There are currently no measures to assess confidence with manual wheelchair use. The objective of this study was to develop and assess the psychometric properties of a new outcome measure, the Wheelchair Use Confidence Scale (WheelCon-M). Purpose 1. To describe situations that challenge confidence with manual wheelchair use from the perspectives of wheelchair users and health care professionals (chapter 2). 2. To select items and assess the test content of the WheelCon-M (chapter 3). 3. To refine items on the WheelCon-M to ensure each item is interpreted as intended (chapter 4). 4. To examine the psychometric properties of the WheelCon-M (internal structure, internal consistency, reliability, and relations to other variables) (chapter 5). Methods Design: This study used a mixed-methods design incorporating qualitative interviews (chapter 2), a Delphi survey (chapter 3), a think aloud process (chapter 4), and a test-retest methodological study (chapter 5). Participants: Wheelchair users participated in the interviews (n=13), Delphi survey (n= 22), think aloud process (n=7), and test-retest (n=83). Health care professionals participated in the interviews (n=16) and the Delphi survey (n=16). Researchers participated in the Delphi survey (n=5). Measures: A semi-structured interview guide was used for the qualitative interviews (chapter 2) and standardized measures were used in the test-retest study (chapter 5), including the Wheelchair Skills Test, version 4.1 (objective and questionnaire versions), Barthel Index, Life Space Assessment, Interpersonal Support Evaluation List, Hospital Anxiety and Depression Scale, Functioning Everyday with a Wheelchair, and a demographic questionnaire. Results The WheelCon-M, version 1.0 was an 84-item scale with items generated from the qualitative interviews. Items were selected and the content validated using the Delphi survey, thus reducing the number of items to 62 (version 2.0). Items were refined using the think aloud process which resulted in a 63-item scale (version 2.1). Support for the psychometrics of the WheelCon-M, version 2.1 was provided in the test-retest study. Conclusions The WheelCon-M, version 2.1 provides a means of measuring confidence with manual wheelchair use from a clinical and research perspective.Medicine, Faculty ofGraduat