When study site contributes to outcomes in a multi-center randomized trial: a secondary analysis of decisional conflict in men with localized prostate cancer

Table 4 Factors that explain study site influence on decisional conflict-results from the multivariable analysis

Variable	Decisional uncertainty		Informed subscale		Values clarity subscale		Support subscale
Variable	Est.	p-value	Est.	p-value	Est.	p-value	Est.	P-value
*Study center		0.47		0.003		0.52		0.002
?Augusta			?5.58				?6.69	0.01
?Philadelphia			0.96				?0.19	0.95
?San Antonio			0.73				?7.56	0.04
?Seattle UW-SCCA			5.83				0.51	0.84
Treatment preference at baseline (no vs. yes)	24.5	<.0001	10.92	<.0001	10.44	<.0001	4.87	0.0005
Caucasian (No vs. Yes)	?4.30	0.16	?4.23	0.13
Intervention Access (Clinic vs. Not Clinic)	?6.33	0.02			?6.17	0.01
Married/Partnered (no vs. yes)							2.95	0.07
Number of doctors		0.006		0.002		0.14		0.05
?0 vs. >1	?5.68	0.01	9.18		4.9		4.51	0.01
?1 vs. >1	?7.52	0.001	5.29		2.0		1.17	0.47
Working status (no vs. yes)	?2.85	0.15	?4.25	0.03
Perceived knowledge				<.0001		<.0001		<.0001
?Fair/A lot vs. some			?16.55		?10.55		?7.00	<.0001
?None/little vs. some			3.03		5.41		2.45	0.26
**STAI
State	0.53	<.0001	0.39	<.0001	0.27	<.0001	0.36	<.0001
Trait			?0.15	0.19
***EPIC scale
Sexual symptoms			?0.07	0.04
Information source
Self (no vs. yes)			2.53	0.21
Health care provider (no vs. yes)			3.09	0.17	3.94	0.07
Media (no vs. yes)	?7.74	0.002

Note: Higher estimates indicate more decisional conflict; *Seattle/Puget Sound Veteran's Administration Hospital is the reference group; **STAI = State Trait Anxiety Inventory; ***EPIC = Expanded Prostate Index Composite-Short Form.

ISSN: 1477-7525