Table 3.

Measures used and time of measurement.

Category of measures and variable		Measure	Timea
			1	2	3
Objective learning outcome
	Knowledge acquisition	Objective tests of knowledge of computer components (eg, keyboard and mouse) and the web (eg, link and scroll bar). Computer knowledge and web knowledge were each measured using 10 items; each item was scored with 1 point if answered correctly and 0 points if answered incorrectly (scoring range 0-20).	✓	✓	✓
	Skill acquisition	3 procedural tests required participants to carry out specific tasks on networked computers: Basic computer and web operation: participants performed 12 basic operations on the computer (eg, open a web browser and go to a website). Each task was scored with 1 point if performed correctly or 0 points if done incorrectly (scoring range 0-12). Information seeking: participants received 4 scenarios in which they were asked to find information about specific health topics on the internet (eg, find at least two treatments for breast cancer). Each scenario was scored from 0 to 2 (0 if no relevant information was found, 1 if some but not all the required information was found, and 2 if all the required information was found; scoring range 0-8). Website evaluation: participants were asked to visit and evaluate the reliability of 8 health information websites. Evaluations were recorded as “Yes” if a website was reliable, “No” if a website was not reliable, and “Can’t decide” if the reliability of a website was unknown. Each website was scored with 1 if the evaluation result was correct or 0 if the evaluation result was incorrect or “Can’t decide” (scoring range 0-8).	✓	✓	✓
eHealth literacy
	eHealth literacy efficacy	The 8-item eHealth literacy scale [14], which measures self-perceived skills and comfort with using IT for health information and decision-making. Items are scored on a 5-point Likert scale; higher scores indicate higher eHealth literacy efficacy (scoring range 8-40; Cronbach α=.89-.97, with good test-retest reliability) [15].	✓	✓	✓
Previous experience
	Previous experience with computers and the internet	6 items, 4 of which measured the duration and frequency of previous computer and internet use. Example question: “How long have you been using a computer?” In total, 2 items measured previous computer class experience. Example: “Have you taken our computer class previously?”	✓
Control variables
	Familiarity with peers in the same class	If and how participants may be related to or familiar with others in the same experimental condition (eg, spouse, sibling, friend, or acquaintance)	✓
	Standard health literacy test	S-TOFHLAb; 2 subscales with 36 questions; scoring range 0 to 36; Cronbach α=.97 (reading) and .68 (numeracy) [45]	✓
	Demographic and health factors	Age, sex, education, health, race and ethnicity, income, and primary language	✓
Postintervention questionnaire
	Satisfaction	How would you evaluate your entire experience in this computer class? (“Extremely dissatisfied,” “Dissatisfied,” “Neither satisfied nor dissatisfied,” “Satisfied,” and “Extremely satisfied”)		✓
	Whom did participants learn from?	During the past 4 weeks, while in class, from whom did you learn about computers? (“Peer student(s),” “Mostly the peer student(s),” “The tutorial and peer(s) equally,” “Mostly the tutorial,” and “The tutorial”)		✓
	Interaction with peers	During the past 4 weeks, how much in-class interaction have you had with your peer(s)? (“None,” “A little,” “Some,” “A lot,” and “Extensive”)		✓

^a1: before the intervention; 2: after the intervention; 3: 6-month follow-up.

^bS-TOFHLA: Short Test of Functional Health Literacy in Adults.