Launching a virtual decision lab: development and field-testing of a web-based patient decision support research platform

Table 4 Feasibility of the web-based patient decision aid: knowledge, preparation for decision making, and decisional conflict scores

Post-decision Aid Measures	Videobooklet Decision Aid used in Clinical Care	Web-based Decision Aid used for this Study	t statistic
	(N = 243)	(n = 126)	(df = 367)
	mean (SD)	mean (SD)	p value
Osteoarthritis Decision Quality Index’s Knowledge Subscale 0 - 100% correct	67% (10%)	75% (11%)	t = 4 p = <0.001
Preparation for Decision Making Scale 0 - 100	70 (26)	74 (30)	t = 1 p = 0.18
Decisional Conflict Scale 0 - 100	15 (14)	19 (15)	t = 2 p = 0.03

Note: Videobooklet data gathered during routine clinical use over the two years prior to the study.
SD = Standard Deviation.
df = degrees of freedom.