{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,3,29]],"date-time":"2025-03-29T16:55:00Z","timestamp":1743267300708,"version":"3.33.0"},"reference-count":38,"publisher":"Public Library of Science (PLoS)","issue":"1","license":[{"start":{"date-parts":[[2025,1,24]],"date-time":"2025-01-24T00:00:00Z","timestamp":1737676800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100011022","name":"Vertex Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011022","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011022","name":"Vertex Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011022","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011022","name":"Vertex Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011022","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011022","name":"Vertex Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011022","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011022","name":"Vertex Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011022","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011022","name":"Vertex Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011022","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011022","name":"Vertex Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011022","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011022","name":"Vertex Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011022","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100011022","name":"Vertex Pharmaceuticals","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100011022","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>The Cystic Fibrosis (CF) Impact Questionnaire (CF-IQ) was qualitatively developed to assess the impact of CF in the context of treatment advancements and increased longevity. This study reports the CF-IQ validation. In this noninterventional validation study, people with CF completed the 40-item CF-IQ and validating patient-reported outcome measures (PROMs) via electronic diaries at enrollment (baseline) and at the 4-week follow-up. Validation consisted of modern methods and focus groups to finalize structural validity, and classical methods to assess internal consistency [1\u20133], test-retest reliability [4,5], concurrent validity [5], and known-groups validity [5] of the CF-IQ. At baseline, 214 adults completed the survey; 193 completed the follow-up survey. Unidimensional item response theory (IRT) models were separately fit to 5 prespecified domains (Control and Burden of CF Treatment Impacts, Physical Activity Impacts, Social Activity Impacts, Emotional Impacts, and Work\/School Limitation Impacts). IRT local dependence (LD) statistics identified 17 redundant items. Two independent CF-patient focus groups (14 total patients) confirmed these findings, and the 17 items were dropped. Each domain defined on the final 23 items achieved the criterion of exact model fit as measured by the root mean squared error of approximation (RMSEA, values = 0), Internal consistency (Cronbach\u2019s \u03b1) values ranged from 0.81 to 0.89, 4 of 5 domains achieved acceptable test-retest reliability, with intraclass correlation coefficient (ICC) values \u2265 0.7, acceptable concurrent validity was achieved for all domains, and known-groups validity was established. The novel CF-IQ is a psychometrically robust PROM capturing patient-centric impacts of CF in the context of the current standard of care.<\/jats:p>","DOI":"10.1371\/journal.pone.0317775","type":"journal-article","created":{"date-parts":[[2025,1,24]],"date-time":"2025-01-24T19:09:23Z","timestamp":1737745763000},"page":"e0317775","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":1,"title":["Psychometric validation of the Cystic Fibrosis Impact Questionnaire (CF-IQ): A patient-reported outcome assessing impacts of cystic fibrosis"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-6018-1367","authenticated-orcid":true,"given":"Daniel","family":"Serrano","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alyssa","family":"Uzumcu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maya","family":"Gerstein","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0890-7742","authenticated-orcid":true,"given":"Nicolai D.","family":"Ayasse","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ella","family":"Engstrom","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Frederick B.","family":"Barnes","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Charles","family":"Iaconangelo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Teja","family":"Thorat","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lisa J.","family":"McGarry","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isabelle","family":"Sermet-Gaudelus","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2025,1,24]]},"reference":[{"issue":"5","key":"pone.0317775.ref001","doi-asserted-by":"crossref","first-page":"1147","DOI":"10.1007\/s11136-018-1798-3","article-title":"COSMIN guideline for systematic reviews of patient-reported outcome measures.","volume":"27","author":"CAC Prinsen","year":"2018","journal-title":"Qual Life Res"},{"issue":"3","key":"pone.0317775.ref002","doi-asserted-by":"crossref","first-page":"996","DOI":"10.1111\/j.1541-0420.2008.01082_11.x","article-title":"Quality of Life: The Assessment, Analysis, and Interpretation of Patient\u2010Reported Outcomes by","volume":"64","author":"JA Sloan","year":"2008","journal-title":"Biometrics"},{"issue":"4","key":"pone.0317775.ref003","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1007\/s11136-010-9606-8","article-title":"The COSMIN checklist for assessing the methodological quality of studies on measurement properties of health status measurement instruments: an international Delphi study.","volume":"19","author":"LB Mokkink","year":"2010","journal-title":"Qual Life Res"},{"issue":"7","key":"pone.0317775.ref004","doi-asserted-by":"crossref","first-page":"e0219854","DOI":"10.1371\/journal.pone.0219854","article-title":"Intraclass correlation\u2014A discussion and demonstration of basic features.","volume":"14","author":"D Liljequist","year":"2019","journal-title":"PLoS One."},{"key":"pone.0317775.ref005","article-title":"Terwee CB User Manual: COSMIN methodology for systematic reviews of Patient\u2010Reported Outcome Measures (PROMs)","author":"PC Mokkink LB","year":"2018"},{"key":"pone.0317775.ref006","author":"Cystic Fibrosis Foundation","year":"2021","journal-title":"2019 Patient Registry: Annual Data Report2020"},{"issue":"10059","key":"pone.0317775.ref007","doi-asserted-by":"crossref","first-page":"2519","DOI":"10.1016\/S0140-6736(16)00576-6","article-title":"Cystic fibrosis.","volume":"388","author":"JS Elborn","year":"2016","journal-title":"Lancet"},{"key":"pone.0317775.ref008","article-title":"ECFS Patient Registry.","author":"European Cystic Fibrosis Society","year":"2022","journal-title":"Annual Data Report. 2018 data2020"},{"issue":"1","key":"pone.0317775.ref009","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1038\/s41572-024-00538-6","article-title":"Cystic fibrosis.","volume":"10","author":"MA Mall","year":"2024","journal-title":"Nat Rev Dis Primers"},{"issue":"1","key":"pone.0317775.ref010","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1378\/chest.123.1.42","article-title":"Questions on life satisfaction for adolescents and adults with cystic fibrosis. Development of a disease-specific questionnaire","volume":"123","author":"L Goldbeck","year":"2003","journal-title":"Chest"},{"issue":"11","key":"pone.0317775.ref011","doi-asserted-by":"crossref","first-page":"946","DOI":"10.1136\/thorax.55.11.946","article-title":"Development of a disease specific health related quality of life measure for adults and adolescents with cystic fibrosis","volume":"55","author":"L Gee","year":"2000","journal-title":"Thorax"},{"issue":"4","key":"pone.0317775.ref012","doi-asserted-by":"crossref","first-page":"2347","DOI":"10.1378\/chest.128.4.2347","article-title":"Development and validation of The Cystic Fibrosis Questionnaire in the United States: a health-related quality-of-life measure for cystic fibrosis","volume":"128","author":"AL Quittner","year":"2005","journal-title":"Chest"},{"issue":"1","key":"pone.0317775.ref013","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1023\/A:1022037320039","article-title":"Development of the Cystic Fibrosis Questionnaire (CFQ) for assessing quality of life in pediatric and adult patients.","volume":"12","author":"B Henry","year":"2003","journal-title":"Qual Life Res."},{"issue":"6","key":"pone.0317775.ref014","doi-asserted-by":"crossref","first-page":"403","DOI":"10.1093\/jpepsy\/25.6.403","article-title":"Translation and linguistic validation of a disease-specific quality of life measure for cystic fibrosis","volume":"25","author":"AL Quittner","year":"2000","journal-title":"J Pediatr Psychol"},{"issue":"6","key":"pone.0317775.ref015","doi-asserted-by":"crossref","first-page":"e108","DOI":"10.1016\/j.jcf.2021.02.009","article-title":"\"Il faut continuer a poser des questions\" patient reported outcome measures in cystic fibrosis: An anthropological perspective.","volume":"20","author":"R Coucke","year":"2021","journal-title":"J Cyst Fibros"},{"issue":"1","key":"pone.0317775.ref016","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1186\/s41687-020-00199-5","article-title":"The Cystic Fibrosis Impact Questionnaire: qualitative development and cognitive evaluation of a new patient-reported outcome instrument to assess the life impacts of cystic fibrosis","volume":"4","author":"KP McCarrier","year":"2020","journal-title":"J Patient Rep Outcomes"},{"issue":"8","key":"pone.0317775.ref017","doi-asserted-by":"crossref","first-page":"967","DOI":"10.1016\/j.jval.2011.06.014","article-title":"Content validity\u2014establishing and reporting the evidence in newly developed patient-reported outcomes (PRO) instruments for medical product evaluation: ISPOR PRO Good Research Practices Task Force Report: Part 1\u2014eliciting concepts for a new PRO instrument.","volume":"14","author":"DL Patrick","year":"2011","journal-title":"Value Health."},{"key":"pone.0317775.ref018","article-title":"Center for Drug Evaluation and Research (CDER), Center for Biologics Evaluation and Research (CBER), Center for Devices and Radiological Health (CDRH).","author":"U.S. Department of Health and Human Services, Food and Drug Administration","year":"2022","journal-title":"Guidance for Industry. Patient-reported outcome measures: use in medical product development to support labeling claims2009"},{"key":"pone.0317775.ref019","article-title":"Patient-focused drug development guidance: methods to identify what is important to patients and select","author":"U.S. Food & Drug Administration","year":"2022","journal-title":"develop or modify fit-for-purpose clinical outcomes assessments2018"},{"key":"pone.0317775.ref020","author":"Rare Patient Voice.","year":"2022","journal-title":"Home page2022"},{"key":"pone.0317775.ref021","doi-asserted-by":"crossref","first-page":"68","DOI":"10.1186\/1741-7015-10-68","article-title":"Development and description of measurement properties of an instrument to assess treatment burden among patients with multiple chronic conditions","volume":"10","author":"V-T Tran","year":"2012","journal-title":"BMC Med"},{"issue":"5","key":"pone.0317775.ref022","doi-asserted-by":"crossref","first-page":"353","DOI":"10.2165\/00019053-199304050-00006","article-title":"The validity and reproducibility of a work productivity and activity impairment instrument.","volume":"4","author":"MC Reilly","year":"1993","journal-title":"Pharmacoeconomics."},{"issue":"5","key":"pone.0317775.ref023","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1016\/j.outlook.2014.05.009","article-title":"Patient-Reported Outcomes Measurement Information System (PROMIS): efficient, standardized tools to measure self-reported health and quality of life.","volume":"62","author":"M Bevans","year":"2014","journal-title":"Nurs Outlook."},{"issue":"5","key":"pone.0317775.ref024","doi-asserted-by":"crossref","first-page":"490","DOI":"10.1037\/hea0000055","article-title":"New English and Spanish social health measures will facilitate evaluating health determinants.","volume":"33","author":"EA Hahn","year":"2014","journal-title":"Health Psychol."},{"issue":"1","key":"pone.0317775.ref025","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/08870440290001494","article-title":"The revised Illness Perception Questionnaire (IPQ-R).","volume":"17","author":"R Moss-Morris","year":"2002","journal-title":"Psychol Health"},{"issue":"7","key":"pone.0317775.ref026","doi-asserted-by":"crossref","first-page":"1267","DOI":"10.1007\/s11136-011-0036-z","article-title":"Psychometric evaluation of the Cystic Fibrosis Questionnaire-Revised in a national sample.","volume":"21","author":"AL Quittner","year":"2012","journal-title":"Qual Life Res"},{"issue":"3","key":"pone.0317775.ref027","doi-asserted-by":"crossref","first-page":"265","DOI":"10.3102\/10769986022003265","article-title":"Local Dependence Indexes for Item Pairs Using Item Response Theory","volume":"22","author":"W-H Chen","year":"1997","journal-title":"Journal of Educational and Behavioral Statistics"},{"key":"pone.0317775.ref028","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1007\/BF02295289","article-title":"A new item response theory modeling approach with applications to unidimensionality assessment and ability estimation","volume":"55","author":"WF Stout","year":"1990","journal-title":"Psychometrika."},{"key":"pone.0317775.ref029","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1037\/1082-989X.1.2.130","article-title":"Power analysis and determination of sample size for covariance structure modeling","volume":"1","author":"R Maccallum","year":"1996","journal-title":"Psychological Methods"},{"key":"pone.0317775.ref030","volume-title":"Test Theory. A Unified Treatment.","author":"RP McDonald","year":"1999"},{"issue":"3","key":"pone.0317775.ref031","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1007\/BF02310555","article-title":"Coefficient alpha and the internal structure of tests","volume":"16","author":"LJ Cronbach","year":"1951","journal-title":"Psychometrika"},{"issue":"2","key":"pone.0317775.ref032","doi-asserted-by":"crossref","first-page":"420","DOI":"10.1037\/0033-2909.86.2.420","article-title":"Intraclass correlations: uses in assessing rater reliability.","volume":"86","author":"PE Shrout","year":"1979","journal-title":"Psychol Bull"},{"key":"pone.0317775.ref033","doi-asserted-by":"crossref","first-page":"6","DOI":"10.18637\/jss.v048.i06","article-title":"mirt: a multidimensional item response theory package for the R environment","volume":"48","author":"RP Chalmers","year":"2012","journal-title":"J Stat Softw"},{"key":"pone.0317775.ref034","volume-title":"flexMIRT\u00ae version 3.51: Flexible multilevel multidimensional item analysis and test scoring [Computer software].","author":"L. Cai","year":"2017"},{"key":"pone.0317775.ref035","unstructured":"SAS. SAS version 9.4. Cary, NC: SAS Institute Inc."},{"key":"pone.0317775.ref036","author":"The R Foundation","year":"2022","journal-title":"What is R?2022"},{"issue":"2","key":"pone.0317775.ref037","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1037\/met0000045","article-title":"Evaluating bifactor models: calculating and interpreting statistical indices.","volume":"21","author":"A Rodriguez","year":"2016","journal-title":"Psychol Methods"},{"issue":"4","key":"pone.0317775.ref038","doi-asserted-by":"crossref","first-page":"245","DOI":"10.1016\/j.jcf.2009.04.003","article-title":"Patient-reported respiratory symptoms in cystic fibrosis.","volume":"8","author":"CH Goss","year":"2009","journal-title":"J Cyst Fibros"}],"container-title":["PLOS ONE"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0317775","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,1,24]],"date-time":"2025-01-24T19:09:34Z","timestamp":1737745774000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0317775"}},"subtitle":[],"editor":[{"given":"Emrah","family":"Gecili","sequence":"first","affiliation":[],"role":[{"role":"editor","vocabulary":"crossref"}]}],"short-title":[],"issued":{"date-parts":[[2025,1,24]]},"references-count":38,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2025,1,24]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0317775","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,1,24]]}}}