Open AccessRasch analysis of the Korean version of the VF‐14: calibration and unidimensionality
Author(s) -
Lee Jae Eun,
Sung Jung Hye
Publication year - 2001
Publication title -
international journal of methods in psychiatric research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.275
H-Index - 73
eISSN - 1557-0657
pISSN - 1049-8931
DOI - 10.1002/mpr.116
Subject(s) - rasch model , item response theory , psychology , polytomous rasch model , scale (ratio) , rating scale , hierarchy , item analysis , measure (data warehouse) , psychometrics , classical test theory , short forms , cognitive psychology , clinical psychology , developmental psychology , data mining , computer science , physics , quantum mechanics , economics , market economy
Abstract The VF‐14 is intended to measure visual functioning based on sets of hierarchically structured items. Rasch item response theory (IRT) provides a methodology to examine the hierarchical structure and unidimensionality of a survey instrument. The purpose of this study is to examine the scale properties (hierarchical structure and unidimensionality) of the VF‐14 using Rasch item response theory methodology in cataract patients (N = 80). The results of the study showed that the Korean version VF‐14 is unidimensional with a hierarchy from easy to hard items, as well as being valid and reliable in the terms of traditional psychometric analysis. The Korean version of the VF‐14 had some significant item spacings (three strata), and the rating‐scale categories were worded well. Therefore, the Korean version of the VF‐14 measures are appropriate for use in and further study of the visual limitations associated with cataract inpatients. Copyright © 2001 Whurr Publishers Ltd.