Evaluation of cross-sectional and longitudinal construct validity of two vision-related quality of life questionnaires: the LVQOL and VCM1.
The Low Vision Quality of Life (LVQOL) questionnaire and the Vision-related Quality of Life Core Measure (VCM1) are two of the many vision-related quality of life (QOL) questionnaires that have been developed in recent years. Although psychometric properties of the LVQOL and VCM1 compare well with other vision-related QOL questionnaires, construct and longitudinal validity have not been assessed (adequately). The purpose of this study was to examine the cross-sectional and longitudinal construct validity of these questionnaires by testing specific pre-specified hypotheses about the relations of these questionnaires with other measures. The percentage of hypotheses regarding the cross-sectional construct validity that were refuted for the LVQOL was 22% for the basic aspects of vision subscale, 50% for the mobility subscale, 39% for the adjustment subscale and 17% for the reading and fine work subscale. For the VCM1 this percentage was 57%. For the longitudinal construct validity the percentage of hypotheses that were refuted ranged from 33 to 75% for the LVQOL subscales and was 50% for the VCM1. In conclusion, cross-sectional construct validity was satisfactory for the LVQOL subscales, but seemed poor for the VCM1. In addition, the longitudinal validity of these scales was poor to moderate.
de Boer
M R
MR
Department of Ophthalmology, VU University Medical Center, Amsterdam, The Netherlands. michiel.deboer@vumc.nl
Terwee
C B
CB
de Vet
H C W
HC
Moll
A C
AC
Völker-Dieben
H J M
HJ
van Rens
G H M B
GH
D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009426:Netherlands; D011594:Psychometrics; D011788:Quality of Life; D011795:Surveys and Questionnaires / Q000592:standards*