Development and validation of NEWSQOL®, the Newcastle Stroke-Specific Quality of Life Measure

Background: A review of stroke-specific quality of life (QOL) measures indicated little evidence of their validity/ reliability. Purpose: To describe the development/validation of a new measure - the Newcastle Stroke-Specific Quality of Life Measure (NEWSQOL). Methods: Phase I: qualitative interviews ( 28 stroke patients) determined QOL issues for inclusion in the measure. Initial items/ response categories were pre-tested ( 30 patients). Administration of the NEWSQOL in the item reduction stage ( 100 patients) identified poorly performing items and factor analysis showed likely domains. Internal consistency was examined. Phase II: NEWSQOL and comparator measures were administered ( 106 patients) to examine validity/ test-retest reliability. Results: Phase I: 140 items were identified for initial inclusion. Qualitative pre-testing led to an extensive revision. Item reduction resulted in a final measure of 56 items in 11 domains ( feelings, activities of daily living/self-care, cognition, mobility, emotion, sleep, interpersonal relationships, communication, pain/sensation, vision, fatigue; Cronbach's alpha = 0.71-0.90). Phase II: NEWSQOL domain scores, except cognition, were moderately/highly correlated (0.45 - 0.76) with relevant comparator measures. NEWSQOL domains feelings, communication and cognition low/moderately correlated with Barthel Index scores ( - 0.49 to - 0.28), as predicted. Test-retest reliability was high (intraclass correlation coefficient range 0.78 - 0.92). Conclusions: NEWSQOL is an acceptable, patient-derived, interviewer-administered, stroke-specific QOL measure with evidence of reliability and validity, making it a promising instrument for assessing QOL after stroke. Involvement of relevant patients in determining the content and format considerably enhances confidence in its validity. Copyright (C) 2004 S. Karger AG, Basel.