Open AccessDevelopment and Initial Validation Analyses of the Living with Idiopathic Pulmonary Fibrosis Questionnaire
Author(s) -
Jeffrey J. Swigris,
David Andrae,
Tara Churney,
Nathan Johnson,
Mary Beth Scholand,
Eric S. White,
Alison Matsui,
Karina Raimundo,
Christopher J. Evans
Publication year - 2020
Publication title -
american journal of respiratory and critical care medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 6.272
H-Index - 374
eISSN - 1535-4970
pISSN - 1073-449X
DOI - 10.1164/rccm.202002-0415oc
Subject(s) - medicine , idiopathic pulmonary fibrosis , quality of life (healthcare) , exploratory factor analysis , physical therapy , debriefing , psychometrics , construct validity , cohort , clinical psychology , lung , nursing , medical education
Rationale: Several new drugs for idiopathic pulmonary fibrosis (IPF) are in development. Tools are needed to assess whether these drugs benefit patients on outcomes that matter most to them. Health-related quality of life (HRQL) is one such outcome. It is influenced by many factors, but symptoms and their impacts are two strong drivers. Objectives: To develop a questionnaire to assess symptoms, disease impacts, and HRQL specifically for patients with IPF. Methods: Working with the U.S. Food and Drug Administration through the Drug Development Tool Qualification process, focus groups, concept elicitation, and cognitive debriefing interviews were conducted to inform the development of a 44-item pilot questionnaire. The pilot paper-and-pen questionnaire was migrated to an equivalent electronic version and field-tested in a 14-day study. Response data were subjected to psychometric testing, including exploratory factor analysis, item calibration using item response theory models, test-retest reliability, and validity testing. Measurements and Main Results: A total of 125 patients with IPF (62.4% men) completed the longitudinal study. The mean ± SD age of the cohort was 69 ± 7.60 years, and the mean FVC% predicted was 71 ± 20.0. After factor and item analyses, 35 items were retained, and these comprise the two modules (symptoms and impacts) of the Living with IPF (L-IPF) questionnaire. The L-IPF yields five scales demonstrating good psychometric properties, including correlation with concurrently collected FVC% predicted and the ability to discriminate between patients with differing levels of IPF severity. Conclusions: The L-IPF is a new questionnaire that assesses symptoms, disease impacts, and HRQL in patients with IPF.