Outcome measurement for COPD: Reliability and validity of the Dyspnea Management Questionnaire

Abstract

The Dyspnea Management Questionnaire (DMQ) is a measure of the psychosocial and behavioral responses to dyspnea for adults with COPD. The research objectives were to evaluate the reliability and validity of an expanded DMQ item pool, as a preliminary step for developing a computer adaptive test. The original 66 items of the DMQ were used for the analyses. The sample included 63 women and 44 men with COPD (n = 107) recruited from two urban medical centers. We used confirmatory factor analysis to test the factor structure of the DMQ and its underlying cognitive-behavioral theoretical base. The internal consistency and test-retest reliability, and breadth of coverage of the expanded DMQ item bank were also evaluated. Five distinct dyspnea domains were confirmed using 56 original items of the DMQ: dyspnea intensity, dyspnea anxiety, activity avoidance, activity self-efficacy, and strategy satisfaction. Overall, the breadth of items was excellent with a good match between sample scores and item difficulty. The DMQ-56 showed good internal consistency reliability (α = 0.85-to 0.96) and good preliminary test-retest reliability over a 3-week interval (ICC = 0.69-0.92). The DMQ demonstrated acceptable levels of reliability and validity for measuring multidimensional dyspnea outcomes after medical, psychological, and behavioral interventions for adults with COPD.