2.2 Design and procedure
Participants' eye movement and duration of gaze were measured using a Tobii-120
eye tracker. Participants were positioned 64 cm away from a 17-in. monitor.
Participants first viewed a succession of five images. As shown in Fig. 1, the images
consisted of five different cereal box covers and their associated nutrition label. The
images were presented in a random order and appeared on the screen for 5 s each. The
interstimulus interval was 1 s. The area of interest (AOI) defined for analysis was the
nutrition labels on the side of the box as outlined in Fig. 1. All the nutritional
information on the nutrition labels was included as the AOI.
The participants were then randomly assigned to the NE group or the control
group. The participants in the NE group were asked to read the educational nutrition
booklet titled, Thumbs Up!® Healthy Eating (Oliverio 2009), for 10 min. Using a
picture-based approach, the book highlights nutritional values on nutrition labels for
various products such as bread, dairy, and drinks as shown in Fig. 2.
The booklet utilizes a “thumbs up” icon for healthy choices (e.g., cereals low in
sugar and high in fiber) and a “thumbs down” icon for unhealthy choices (e.g., cereals
high in sugar and low in fiber). Participants in the control group were asked to
complete a word find puzzle with a beach theme for 10 min. The words were simple
and consistent with the word level of the nutrition booklet. Most participants completed
the word find puzzle within the 10 min; others could not locate one or two
words. The same succession of five cereal boxes was displayed on the screen for the
posttest. The participants' eye position and movement were recorded for the posttest.