Psychometric Validation of the KDQoL-36 in Dialysis Using Item Response Theory and Computer Adaptive Testing

Psychometric Validation of the KDQoL-36 in Dialysis Using Item Response Theory and Computer Adaptive Testing | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Psychometric Validation of the KDQoL-36 in Dialysis Using Item Response Theory and Computer Adaptive Testing Jasmine Ion Titapiccolo, Sugandha Saxena, Francesco Bellocchio, and 15 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7751098/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Health-Related Quality of Life (HRQoL) is a critical outcome in end-stage kidney disease care. The Kidney Disease Quality of Life-36 (KDQoL-36) is widely used but presents limitations in length and personalization, which may reduce its clinical utility. We evaluated the psychometric performance of a multidimensional Item Response Theory (IRT) model for KDQoL-36 and simulated a Computerized Adaptive Testing (CAT) version in a large European dialysis cohort. Methods We included 8,325 KDQoL-36 responses from chronic dialysis patients in 170 NephroCare clinics across six countries. Psychometric properties were assessed using confirmatory factor analysis and bifactor IRT modeling. CAT simulations were conducted to evaluate reliability and burden reduction. Construct and criterion validity were assessed using hospitalization outcomes and known-group comparisons. Results Bifactor models demonstrated superior fit for both SF12 and disease-specific KDQoL-36 domains, with excellent reliability (ω > 0.90). IRT-based scores showed high agreement with classical test theory (R²: 0.75–0.98) and differentiated patient groups by hospitalization risk. CAT simulations showed strong agreement with full-length scores (R²: 0.93–0.99), reduced item count by 22–36% and saved up to 10 workdays per survey cycle. CCAT administered 7.67 ± 2.58 items per patient in SF12 domain and 18.75 ± 4.09 for KDQoL-36 diseases specific domain while preserving measurement precision. Conclusion Multidimensional IRT modeling supports the KDQoL-36 as a reliable, valid measure of HRQoL in dialysis care. CAT implementation offers substantial efficiency gains with minimal loss of information, reducing patient and staff burden while enhancing integration of HRQoL into routine clinical practice. Health-Related Quality of Life (HRQoL) Kidney Disease Quality of Life-36 (KDQoL-36) Dialysis Patients Item Response Theory (IRT) Computerized Adaptive Testing (CAT) Patient-Reported Outcomes (PROMs) Full Text Additional Declarations Competing interest reported. All authors are employees of Fresenius Medical Care. Supplementary Files PaperFiguresPsychometricValidation290925.docx AppendicesPsychometricValidation290925.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7751098","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":532633481,"identity":"c910734f-fc00-4161-9e69-40f5f48a3346","order_by":0,"name":"Jasmine Ion Titapiccolo","email":"","orcid":"","institution":"Fresenius Medical Care, Global Medical Office, RRI","correspondingAuthor":false,"prefix":"","firstName":"Jasmine","middleName":"Ion","lastName":"Titapiccolo","suffix":""},{"id":532633482,"identity":"f62c861d-a722-43d9-a22c-d0f9865dd82d","order_by":1,"name":"Sugandha Saxena","email":"","orcid":"","institution":"Fresenius Medical Care (India)","correspondingAuthor":false,"prefix":"","firstName":"Sugandha","middleName":"","lastName":"Saxena","suffix":""},{"id":532633483,"identity":"1b82d6fb-8bed-4756-8d1b-cf2d143edc0b","order_by":2,"name":"Francesco Bellocchio","email":"","orcid":"","institution":"Fresenius Medical Care, Global Medical Office, RRI","correspondingAuthor":false,"prefix":"","firstName":"Francesco","middleName":"","lastName":"Bellocchio","suffix":""},{"id":532633484,"identity":"c1724dc9-3ad2-4908-86fa-0bdfe7580475","order_by":3,"name":"Abraham Rincon Bello","email":"","orcid":"","institution":"Fresenius Medical Care","correspondingAuthor":false,"prefix":"","firstName":"Abraham","middleName":"Rincon","lastName":"Bello","suffix":""},{"id":532633487,"identity":"b71bc77f-180e-4157-bdb2-5fcbac34362e","order_by":4,"name":"Maria-Eva Baró Salvador","email":"","orcid":"","institution":"Fresenius Medical Care","correspondingAuthor":false,"prefix":"","firstName":"Maria-Eva","middleName":"Baró","lastName":"Salvador","suffix":""},{"id":532633488,"identity":"4ac4eafe-90d4-4f1d-ba17-eeed7d506d34","order_by":5,"name":"Christophe Ridel","email":"","orcid":"","institution":"Fresenius Medical Care","correspondingAuthor":false,"prefix":"","firstName":"Christophe","middleName":"","lastName":"Ridel","suffix":""},{"id":532633490,"identity":"c15b9afc-994b-4c81-b721-360351c7c648","order_by":6,"name":"Mark Gilchrist","email":"","orcid":"","institution":"Fresenius Medical Care","correspondingAuthor":false,"prefix":"","firstName":"Mark","middleName":"","lastName":"Gilchrist","suffix":""},{"id":532633491,"identity":"3fbf4f37-f389-4417-b5fa-d2762ed77512","order_by":7,"name":"Alessandro Pizzo","email":"","orcid":"","institution":"Fresenius Medical Care","correspondingAuthor":false,"prefix":"","firstName":"Alessandro","middleName":"","lastName":"Pizzo","suffix":""},{"id":532633492,"identity":"1381390a-4d91-4295-b788-a1a7e2e17881","order_by":8,"name":"Mario Cioffi","email":"","orcid":"","institution":"Fresenius Medical Care","correspondingAuthor":false,"prefix":"","firstName":"Mario","middleName":"","lastName":"Cioffi","suffix":""},{"id":532633493,"identity":"18e37f09-8822-4062-9d48-c6b9e4a72ea3","order_by":9,"name":"Adrian. 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All authors are employees of Fresenius Medical Care.","formattedTitle":"Psychometric Validation of the KDQoL-36 in Dialysis Using Item Response Theory and Computer Adaptive Testing","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Health-Related Quality of Life (HRQoL), Kidney Disease Quality of Life-36 (KDQoL-36), Dialysis Patients, Item Response Theory (IRT), Computerized Adaptive Testing (CAT), Patient-Reported Outcomes (PROMs)","lastPublishedDoi":"10.21203/rs.3.rs-7751098/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7751098/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003eHealth-Related Quality of Life (HRQoL) is a critical outcome in end-stage kidney disease care. The Kidney Disease Quality of Life-36 (KDQoL-36) is widely used but presents limitations in length and personalization, which may reduce its clinical utility. We evaluated the psychometric performance of a multidimensional Item Response Theory (IRT) model for KDQoL-36 and simulated a Computerized Adaptive Testing (CAT) version in a large European dialysis cohort.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eWe included 8,325 KDQoL-36 responses from chronic dialysis patients in 170 NephroCare clinics across six countries. Psychometric properties were assessed using confirmatory factor analysis and bifactor IRT modeling. CAT simulations were conducted to evaluate reliability and burden reduction. Construct and criterion validity were assessed using hospitalization outcomes and known-group comparisons.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eBifactor models demonstrated superior fit for both SF12 and disease-specific KDQoL-36 domains, with excellent reliability (ω\u0026thinsp;\u0026gt;\u0026thinsp;0.90). IRT-based scores showed high agreement with classical test theory (R\u0026sup2;: 0.75\u0026ndash;0.98) and differentiated patient groups by hospitalization risk. CAT simulations showed strong agreement with full-length scores (R\u0026sup2;: 0.93\u0026ndash;0.99), reduced item count by 22\u0026ndash;36% and saved up to 10 workdays per survey cycle. CCAT administered 7.67\u0026thinsp;\u0026plusmn;\u0026thinsp;2.58 items per patient in SF12 domain and 18.75\u0026thinsp;\u0026plusmn;\u0026thinsp;4.09 for KDQoL-36 diseases specific domain while preserving measurement precision.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eMultidimensional IRT modeling supports the KDQoL-36 as a reliable, valid measure of HRQoL in dialysis care. CAT implementation offers substantial efficiency gains with minimal loss of information, reducing patient and staff burden while enhancing integration of HRQoL into routine clinical practice.\u003c/p\u003e","manuscriptTitle":"Psychometric Validation of the KDQoL-36 in Dialysis Using Item Response Theory and Computer Adaptive Testing","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-22 20:08:26","doi":"10.21203/rs.3.rs-7751098/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0c53a78f-6383-4a84-86f4-ff042e0c90ae","owner":[],"postedDate":"October 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-11-25T20:38:24+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-22 20:08:26","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7751098","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7751098","identity":"rs-7751098","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}