Table 2.

Interview guide to obtain participants’ comments on the video recording of his or her eye movement behavior.

Screen	Questions to ask
Summary result screen of post surrogates
	For post surrogates with eye fixation, ask What attracted your eyes to these posts? Why is this interesting?
	For post surrogates clicked on, ask Why did you select this post for further reading?
	Look through the post surrogates without eye fixations and point to a few titles that appear similar in topic to the post surrogates the participant had clicked on, and ask Why was this post not interesting?
Detailed post screen
	Point out text segments in the post content with eye fixation and ask Is this information useful or relevant?
	Finally, ask Why do you think this post is relevant or not relevant?