BACKGROUND: As part of a larger study whose objective is to develop an abbreviated version of the EORTC QLQ-C30 suitable for research in palliative care, analyses were conducted to determine the feasibility of generating a shorter version of the 4-item emotional functioning (EF) scale that could be scored in the original metric. METHODS: We used data from 24 European cancer studies conducted in 10 different languages (n = 8242). Item selection was based on analyses by item response theory (IRT). Based on the IRT results, a simple scoring algorithm was developed to predict the original 4-item EF sum scale score from a reduced number of items. RESULTS: Both a 3-item and a 2-item version (item 21 'Did you feel tense?' and item 24 'Did you feel depressed?') predicted the total score with excellent agreement and very little bias. In group comparisons, the 2-item scale led to the same conclusions as those based on the original 4-item scale with little or no loss of measurement efficiency. CONCLUSION: Although these results are promising, confirmatory studies are needed based on independent samples. If such additional studies yield comparable results, incorporation of the 2-item EF scale in an abbreviated version of the QLQ-C30 for use in palliative care research settings would be justified. The analyses reported here demonstrate the usefulness of the IRT-based methodology for shortening questionnaire scales.
BACKGROUND: As part of a larger study whose objective is to develop an abbreviated version of the EORTC QLQ-C30 suitable for research in palliative care, analyses were conducted to determine the feasibility of generating a shorter version of the 4-item emotional functioning (EF) scale that could be scored in the original metric. METHODS: We used data from 24 European cancer studies conducted in 10 different languages (n = 8242). Item selection was based on analyses by item response theory (IRT). Based on the IRT results, a simple scoring algorithm was developed to predict the original 4-item EF sum scale score from a reduced number of items. RESULTS: Both a 3-item and a 2-item version (item 21 'Did you feel tense?' and item 24 'Did you feel depressed?') predicted the total score with excellent agreement and very little bias. In group comparisons, the 2-item scale led to the same conclusions as those based on the original 4-item scale with little or no loss of measurement efficiency. CONCLUSION: Although these results are promising, confirmatory studies are needed based on independent samples. If such additional studies yield comparable results, incorporation of the 2-item EF scale in an abbreviated version of the QLQ-C30 for use in palliative care research settings would be justified. The analyses reported here demonstrate the usefulness of the IRT-based methodology for shortening questionnaire scales.
Authors: Morten Aa Petersen; Mogens Groenvold; Jakob B Bjorner; Neil Aaronson; Thierry Conroy; Ann Cull; Peter Fayers; Marianne Hjermstad; Mirjam Sprangers; Marianne Sullivan Journal: Qual Life Res Date: 2003-06 Impact factor: 4.147
Authors: D F Cella; D S Tulsky; G Gray; B Sarafian; E Linn; A Bonomi; M Silberman; S B Yellen; P Winicour; J Brannon Journal: J Clin Oncol Date: 1993-03 Impact factor: 44.544
Authors: N K Aaronson; S Ahmedzai; B Bergman; M Bullinger; A Cull; N J Duez; A Filiberti; H Flechtner; S B Fleishman; J C de Haes Journal: J Natl Cancer Inst Date: 1993-03-03 Impact factor: 13.506
Authors: Jorunn L Helbostad; Line M Oldervoll; Peter M Fayers; Marit S Jordhøy; Kenneth C H Fearon; Florian Strasser; Stein Kaasa Journal: Support Care Cancer Date: 2010-03-26 Impact factor: 3.603
Authors: Élodie de Bock; Jean-Benoit Hardouin; Myriam Blanchin; Tanguy Le Neel; Gildas Kubis; Véronique Sébille Journal: Qual Life Res Date: 2014-02-23 Impact factor: 4.147
Authors: Juan Ignacio Arraras; Fernando Arias de la Vega; Gemma Asin; Mikel Rico; Uxue Zarandona; Clara Eito; Koldo Cambra; Marta Barrondo; Marta Errasti; Juan Verdún; Jose Rivadeneira; Miguel Angel Dominguez Journal: Qual Life Res Date: 2013-09-04 Impact factor: 4.147
Authors: Véronique Sébille; Jean-Benoit Hardouin; Tanguy Le Néel; Gildas Kubis; François Boyer; Francis Guillemin; Bruno Falissard Journal: BMC Med Res Methodol Date: 2010-03-25 Impact factor: 4.615
Authors: Morten Aa Petersen; Mogens Groenvold; Neil Aaronson; Peter Fayers; Mirjam Sprangers; Jakob B Bjorner Journal: Qual Life Res Date: 2006-04 Impact factor: 4.147
Authors: Alla Sikorskii; Charles W Given; Barbara Given; Sangchoon Jeon; Veronica Decker; David Decker; Victoria Champion; Ruth McCorkle Journal: J Pain Symptom Manage Date: 2007-07-09 Impact factor: 3.612