Objective: The aim of this study was to determine the conceptual framework, item pool, and psychometric properties of a new function-neutral measure of health-related quality-of-life (HRQOL).
Design: This is an expert panel review of existing measures of HRQOL and development of a conceptual model, core constructs, and item pool and a validation by experts in specific disabilities and in cultural competence. Items were cognitively tested, pilot tested for functional bias, field tested with a national sample of adults with various limitations, and reliability tested via repeat administration. Final item selection was based on analyses of factor structure, demographic bias, variance in likelihood of endorsement, and item-total correlation. Psychometric properties were demonstrated through differential item functioning analyses, factor analyses, correlations, and item response theory analyses.
Results: The results supported a four-domain conceptual model of HRQOL (physical health, mental health, social health, and life satisfaction and beliefs) for a 42-item HRQOL measure with an ancillary 15-item environment scale. The measure has strong internal consistency (α = 0.88–0.97), known-groups validity, and test-retest reliability (r = 0.83–0.91). Tests of convergent and divergent validity confirmed the ability of the Function-Neutral Health-Related Quality of Life to measure health while being relatively free of content assessing function.
Conclusions: A conceptually grounded four-domain, function-neutral measure of HRQOL that is appropriate for use with persons with and without various functional limitations was developed.
From the Oregon Health & Science University, Portland, Oregon (GLK, W-HJ, TAH, CED, RS, JJP); Warner Pacific College, Portland, Oregon (GHR); University of Florida, Gainesville (EMA); University of Illinois, Chicago (GTF); Baylor College of Medicine, Houston, Texas (MAN); and Oregon State University, Corvallis (BJC).
All correspondence and requests for reprints should be addressed to: Gloria L. Krahn, PhD, MPH, Division of Human Development and Disability/National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, 1600 Clifton Rd NE, MS E88, Atlanta, GA 30333.
Gloria L. Krahn is now with the Centers for Disease Control and Prevention, Atlanta, GA.
Trevor A. Hall is now with the Northwest Neurobehavioral Health, Boise, ID.
Elena M. Andresen is now with the Oregon Health & Science University, Portland.
Charles E. Drum is now with the University of New Hampshire, Durham.
Rie Suzuki is now with the University of Michigan-Flint.
Jana J. Peterson is now with the Pacific University, Forest Grove, OR.
Supported by funds from the United States Department of Education, National Institute on Disability and Rehabilitation Research (NIDRR), under grant number H133B040034, principal investigator Gloria Krahn, PhD, MPH, and project officer Phillip Beatty, PhD.
The findings and conclusions in this article are those of the authors and do not necessarily represent the official position of the United States Department of Education or the Centers for Disease Control and Prevention. Endorsement by the federal government should not be assumed.
Presented in part at the RRTC State of the Science Conference, May 2008, Portland, OR; International Society for Quality of Life Research, October 2009, New Orleans, LA; and American Public Health Association, November 2010, Denver, CO.
Financial disclosure statements have been obtained, and no conflicts of interest have been reported by the authors or by any individuals in control of the content of this article.