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.
Department of Ophthalmology, VU University Medical Center, Amsterdam, The Netherlands. michiel.deboer@vumc.nl
M R
MR
de Boer
C B
CB
Terwee
H C W
HC
de Vet
A C
AC
Moll
H J M
HJ
Völker-Dieben
G H M B
GH
van Rens
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*