Assessing the internal consistency and temporal stability of advance directives generated by an interactive, online computer program.
OBJECTIVE
Evaluate the internal consistency and temporal stability of advance directives (ADs) generated by an interactive, online computer program.


METHODS
33 participants completed the program at three visits, 2 weeks apart. Agreement rates were calculated for theGeneral Wishescomponent of the AD. The test-retest method was used to examine the temporal stability of theSpecific Wish for Treatmentcomponent which contains five clinical scenarios.


RESULTS
General Wishesremained stable with 94% selecting the identical response at each visit. For theSpecific Wish for Treatmentscale,significant variations in test-retest correlations existed (ie, ρ=0.32-0.78, between time points 1 and 2); however within scenario, correlations did not significantly vary between time points. Temporal stability was lower in theSpecific Wish for Treatmentscale compared withGeneral Wishes (average ρ=0.59, between time points 1 and 2; and ρ=0.75, between time points 2 and 3).


CONCLUSIONS
ADs generated by an online decision aid demonstrate good temporal stability, with highest stability forGeneral Wishesand moderate stability forSpecific Wish for Treatmentregarding medical treatments in specific clinical scenarios. Internal consistency for wish for treatment across all time points and scenarios was high (Cronbach α>0.90).
Departments of Surgery, Public Health Sciences, and Medicine, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania, USA.
Jane R
JR
Schubart
Department of Public Health Sciences, University of Virginia, School of Medicine, Charlottesville, Virginia, USA.
Fabian
F
Camacho
Departments of Humanities and Medicine, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania, USA.
Michael J
MJ
Green
Department of Pediatrics, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania, USA.
Kimberly A
KA
Rush
Departments of Humanities and Pediatrics, The Pennsylvania State University, College of Medicine, Hershey, Pennsylvania, USA.
Benjamin H
BH
Levi
D000328:Adult; D016223:Advance Directives; D000368:Aged; D000369:Aged, 80 and over; D003661:Decision Support Techniques; D006801:Humans; D020407:Internet; D008875:Middle Aged; D057240:Patient Preference; D014584:User-Computer Interface
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