Visibility and characteristics of the mobile phones for elderly people
Although mobile phones (MPs) have become important IT devices, there are few studies on the visibility of MPs for elderly people. Using six types of MPs, we analysed the reading performance among elderly people who read 11 numerics on each MP. The subjects were 130 people aged 18 to 86 years, including 60 people over 60 years of age. The subjects' visual functions of cataract cloudiness (CC) and near vision for a 50 cm distant target (NV) were measured. In a twoway ANOVA, two kinds of dependant variables, reading speed (RS) and the number of errors in reading (Error) were used for the subjects' reading performance. Two independent variables were taken from five variables. Each time one variable was fixed as the type of MPs. The other was taken as either age, CC, NV, individual history on MP operation or room illuminance (RI). Eventually, 10 ANOVAs were calculated. Significant differences were found in all ANOVAs except that for RI. We undertook a multiple logistic regression analysis. Independent variables of CC, NV and vertical length of characters (VL) and two kinds of dependent variables, RS and Error, were used. Visual functions and a short VL were related to slow RS and increased Errors.