Test-retest reliability and responsiveness of the shortened disability arm shoulder hand (QuickDASH) questionnaire: a pilot study

Abstract

The aim of this dissertation was to determine the test-retest reliability and responsiveness of the shortened Disability Arm Shoulder Hand (QuickDASH) questionnaire as a functional outcome measure in a primary health care setting. The QuickDASH Questionnaire was developed to reduce the burden of administration to both the clinician and patient when assessing functional impairment of the upper extremity. An analysis of current literature on the QuickDASH has provided limited evidence that it is a reliable and responsive instrument in a primary health care setting. A literature review on the key features of functional outcome measures plus instruments available to physiotherapists used in assessing functional status of the upper extremity was conducted. The QuickDASH questionnaire was identified as requiring further psychometric analysis. The pilot study was a questionnaire based, cross sectional, longitudinal study of patients with upper extremity injuries. Participants presenting for treatment for upper extremity injuries (n=35) were recruited from private physiotherapy clinics. Participants completed the QuickDASH questionnaire on three occasions, the first prior to treatment, the second 24 -48 hours later and the third at discharge or at six weeks, which ever event occurred first. At this time the participant and therapist were asked to complete a Global Discharge Questionnaire, which rated the current overall condition of the upper extremity and the perceived level of change that had occurred. Reliability was analysed by calculating an Intraclass Correlation Coefficient and Bland and Altman plots and limits of agreement. Responsiveness was analysed by calculating the Effect Size and Standard Response Mean. The Minimal Clinical Importance Difference (MCID) to assess responsiveness was calculated using an anchor approach. The correlation between the physiotherapist and patient perceived level of overall condition of upper extremity disability was also analysed by an Intraclass Correlation Coefficient. Results demonstrated inconclusive test retest reliability. Responsiveness was demonstrated to be very strong (ES = 1.02, SRM = 1.1). The MCID was calculated to be 19 points. There was a strong correlation between patient and therapist perception of overall current condition of upper extremity disability with an ICC of 0.88. These results support that the QuickDASH is a responsive instrument at measuring patient perceived functional change over time in a primary health setting. Reliability was not conclusively established. Additionally, support was found that therapists are in agreement with patients as to the level of functional impairment over a six week timeframe.