title: Defining clinically meaningful change in health-related quality of life.
abstract: This article reviews current approaches to defining clinically meaningful change in health-related quality of life (HRQOL) and provides guidelines for their use. Definitions of clinically meaningful change are discussed. Two broad methods for identifying clinically meaningful change are contrasted: anchor-based methods and distribution-based methods. Anchor-based methods include cross-sectional approaches and longitudinal approaches. Distribution-based methods include those based on statistical significance, sample variability, and measurement precision. Anchor-based and distribution-based methods have advantages and limitations, and neither seems to be superior to the other. An integrated system for defining clinically meaningful change is recommended that combines anchor-based and distribution-based methods. We propose a new terminology for describing meaningful change derived from anchor-based and distribution-based methods.
authors.affiliation: Neuropsychiatric Research Institute, 700 First Avenue South, Fargo, ND 58107, USA. rcrosby@nrifargo.com <rcrosby@nrifargo.com>
authors.forename: Ross D
authors.initials: RD
authors.lastname: Crosby
authors.forename: Ronette L
authors.initials: RL
authors.lastname: Kolotkin
authors.forename: G Rhys
authors.initials: GR
authors.lastname: Williams
mesh_terms: D006304:Health Status; D006801:Humans; D008019:Life Style; D011379:Prognosis; D011788:Quality of Life; D013223:Statistics as Topic; D016896:Treatment Outcome