Table 4.

Testlets variables for Performance + Squinting and Satisfaction + Squinting used for nominal IRT

	Squinting
	Yes, but I still could not read any of the text	Yes, and squinting helped me read some or all of the text	No, I did not squint
Performance
“I could not read any of the text due to problems seeing up close”	1	3	5
“Poor”	2	3	6
“Fair”	2	4	7
“Good”	2	4	8
“Very Good”	2	4	9
“Excellent”	2	4	10
Satisfaction
“Very dissatisfied”	1	2	4
“Dissatisfied”	1	2	5
“Neither satisfied nor dissatisfied”	1	3	6
“Satisfied”	1	3	7
“Very satisfied”	1	3	8