TY - JOUR
T1 - Differential item functioning (DIF) analyses of health-related quality of life instruments using logistic regression
AU - Scott, Neil William
AU - Fayers, Peter
AU - Aaronson, Neil K.
AU - Bottomley, Andrew
AU - de Graeff, Alexander
AU - Groenvold, Mogens
AU - Gundy, Chad
AU - Koller, Michael
AU - Petersen, Morten A.
AU - Sprangers, Mirjam A. G.
AU - EORTC Quality Life Group, Quality Life Cross-Cultural Meta-Analysis Group
PY - 2010/8/4
Y1 - 2010/8/4
N2 - Background: Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise when testing for DIF in HRQoL instruments. We focus on logistic regression methods, which are often used because of their efficiency, simplicity and ease of application.
Methods: A review of logistic regression DIF analyses in HRQoL was undertaken. Methodological articles from other fields and using other DIF methods were also included if considered relevant.
Results: There are many competing approaches for the conduct of DIF analyses and many criteria for determining what constitutes significant DIF. DIF in short scales, as commonly found in HRQL instruments, may be more difficult to interpret. Qualitative methods may aid interpretation of such DIF analyses.
Conclusions: A number of methodological choices must be made when applying logistic regression for DIF analyses, and many of these affect the results. We provide recommendations based on reviewing the current evidence. Although the focus is on logistic regression, many of our results should be applicable to DIF analyses in general. There is a need for more empirical and theoretical work in this area.
AB - Background: Differential item functioning (DIF) methods can be used to determine whether different subgroups respond differently to particular items within a health-related quality of life (HRQoL) subscale, after allowing for overall subgroup differences in that scale. This article reviews issues that arise when testing for DIF in HRQoL instruments. We focus on logistic regression methods, which are often used because of their efficiency, simplicity and ease of application.
Methods: A review of logistic regression DIF analyses in HRQoL was undertaken. Methodological articles from other fields and using other DIF methods were also included if considered relevant.
Results: There are many competing approaches for the conduct of DIF analyses and many criteria for determining what constitutes significant DIF. DIF in short scales, as commonly found in HRQL instruments, may be more difficult to interpret. Qualitative methods may aid interpretation of such DIF analyses.
Conclusions: A number of methodological choices must be made when applying logistic regression for DIF analyses, and many of these affect the results. We provide recommendations based on reviewing the current evidence. Although the focus is on logistic regression, many of our results should be applicable to DIF analyses in general. There is a need for more empirical and theoretical work in this area.
KW - mental-state-examination
KW - Mantel-Haenszel procedures
KW - cross-cultural validity
KW - response theory
KW - EORTC QLQ-C30
KW - comparing translations
KW - measurement invariance
KW - depressive symptoms
KW - Spanish translation
KW - measurement bias
U2 - 10.1186/1477-7525-8-81
DO - 10.1186/1477-7525-8-81
M3 - Article
C2 - 20684767
VL - 8
JO - Health and Quality of Life Outcomes
JF - Health and Quality of Life Outcomes
SN - 1477-7525
M1 - 81
ER -