TY - JOUR
T1 - Development of computerized adaptive testing (CAT) for the EORTC QLQ-C30 physical functioning dimension
AU - Petersen, Morten Aa
AU - Groenvold, Mogens
AU - Aaronson, Neil K
AU - Chie, Wei-Chu
AU - Conroy, Thierry
AU - Costantini, Anna
AU - Fayers, Peter
AU - Helbostad, Jorunn
AU - Holzner, Bernhard
AU - Kaasa, Stein
AU - Singer, Susanne
AU - Velikova, Galina
AU - Young, Teresa
N1 - Acknowledgments
The study was funded by grants from the EORTC Quality of Life Group. National Taiwan University, grant National Science Council, Taiwan, No. 95-2314-B-002-266-MY2, 97-2314-B-002-020-MY3.
PY - 2011/5
Y1 - 2011/5
N2 - PURPOSE: Computerized adaptive test (CAT) methods, based on item response theory (IRT), enable a patient-reported outcome instrument to be adapted to the individual patient while maintaining direct comparability of scores. The EORTC Quality of Life Group is developing a CAT version of the widely used EORTC QLQ-C30. We present the development and psychometric validation of the item pool for the first of the scales, physical functioning (PF). METHODS: Initial developments (including literature search and patient and expert evaluations) resulted in 56 candidate items. Responses to these items were collected from 1,176 patients with cancer from Denmark, France, Germany, Italy, Taiwan, and the United Kingdom. The items were evaluated with regard to psychometric properties. RESULTS: Evaluations showed that 31 of the items could be included in a unidimensional IRT model with acceptable fit and good content coverage, although the pool may lack items at the upper extreme (good PF). There were several findings of significant differential item functioning (DIF). However, the DIF findings appeared to have little impact on the PF estimation. CONCLUSIONS: We have established an item pool for CAT measurement of PF and believe that this CAT instrument will clearly improve the EORTC measurement of PF.
AB - PURPOSE: Computerized adaptive test (CAT) methods, based on item response theory (IRT), enable a patient-reported outcome instrument to be adapted to the individual patient while maintaining direct comparability of scores. The EORTC Quality of Life Group is developing a CAT version of the widely used EORTC QLQ-C30. We present the development and psychometric validation of the item pool for the first of the scales, physical functioning (PF). METHODS: Initial developments (including literature search and patient and expert evaluations) resulted in 56 candidate items. Responses to these items were collected from 1,176 patients with cancer from Denmark, France, Germany, Italy, Taiwan, and the United Kingdom. The items were evaluated with regard to psychometric properties. RESULTS: Evaluations showed that 31 of the items could be included in a unidimensional IRT model with acceptable fit and good content coverage, although the pool may lack items at the upper extreme (good PF). There were several findings of significant differential item functioning (DIF). However, the DIF findings appeared to have little impact on the PF estimation. CONCLUSIONS: We have established an item pool for CAT measurement of PF and believe that this CAT instrument will clearly improve the EORTC measurement of PF.
U2 - 10.1007/s11136-010-9770-x
DO - 10.1007/s11136-010-9770-x
M3 - Article
C2 - 20972628
VL - 20
SP - 479
EP - 490
JO - Quality of Life Research
JF - Quality of Life Research
SN - 0962-9343
IS - 4
ER -
