Development of a conceptual framework and calibrated item banks to measure patient-reported dyspnea severity and related functional limitations

Value Health. Mar-Apr 2011;14(2):291-306. doi: 10.1016/j.jval.2010.06.001.

Abstract

Objectives: Chronic obstructive pulmonary disease is a major global health problem. Although several patient-reported outcome (PRO) measures of chronic obstructive pulmonary disease exist, none were developed using patient-driven concept development. We developed an item bank for dyspnea severity and related functional limitations on the basis of a PRO conceptual framework derived from patient input.

Methods: We identified a large pool of existing items based on a conceptual framework and literature review. Using patient and expert review panels and an item refinement/modification process, we developed an item bank aligned with the conceptual framework, which subsequently underwent psychometric testing via an online Internet panel of dyspnea patients (N = 608).

Results: Exploratory factor analysis suggested a dominant first factor accounting for about 78% of the total variance. Confirmatory factor analysis supported a unidimensional model. Item response theory analysis demonstrated good model fit, and differential item functioning analyses indicated that the 33-item scale showed potential for measurement equivalence across sex. A 10-item short form produced comparable scores (r = 0.98) and a computerized adaptive-testing simulation indicated efficient measurement with fewer items (mean 4.65 items).

Conclusions: An efficient patient-reported measure of dyspnea severity and related functional limitations, based on a patient-driven PRO conceptual framework, is now available for further validation and use.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Activities of Daily Living
  • Dyspnea / physiopathology
  • Dyspnea / psychology*
  • Factor Analysis, Statistical
  • Female
  • Humans
  • Male
  • Psychometrics / methods*
  • Pulmonary Disease, Chronic Obstructive / physiopathology*
  • Reproducibility of Results
  • Self Report
  • Severity of Illness Index*
  • Surveys and Questionnaires
  • United States