Table 3.

Effect of decision aids on patients’ decisions

Decision	Decision aid			Comparison intervention		Weight	Relative risk (95% CI)
	No of patients	% choosing option		No of patients	% choosing option
Major surgery
Coronary revascularisation16	61	41		48	58	26.4	0.7 (0.5 to 1.0)
Coronary revascularisation25	86	59		94	76	57.2	0.79 (0.6 to 1.0)
Prostatectomy15	104	5		123	8	6.2	0.74 (0.3 to 2)
Mastectomy29	30	24		30	42	10.1	0.58 (0.3 to 1.0)
Total (fixed effects χ2=0.73 (df=3), Z=3.18)	281			295		100	0.74 (0.6 to 0.9)
Circumcision of newborn boys
Maisels et al23	23	91.3		28	96.4	67.3	0.95 (0.8 to 1.1)
Herrara et al21	56	84		47	87	32.7	1.07 (0.9 to 1.3)
Total (χ2=0.02 (df=1), Z=0.76)	79			75			0.96 (0.85 to 1.07)
Testing for prostate specific antigen
Davison and Degner19	50	48		50	38	31.1	1.26 (0.8 to 2)
Flood et al20	103	11.7		93	22.6	21.8	0.52 (0.3 to 1.0)
Wolf et al31	103	60.2		102	76.5	47.2	0.79 (0.6 to 0.9)
Total (random effects χ2=5.56 (df=2), Z=0.91)	256			245		100	0.83 (0.6 to 1.3)
Other screening
BRCA1 gene test22	122	69.7		164	65.2	38	1.07 (0.9 to 1.3)
Amniocentesis30	441	37		431	34.1	62	1.08 (0.9 to 1.3)
Total (fixed effects χ2=0.02 (df=1), Z=1.15)	563			595		100	1.08 (0.95 to 1.22)
Other
Hepatitis B vaccine17	753	23.4		263	13.3		1.76 (1.3 to 2.5)
Dental surgery27	37	85		37	70.3		1.19 (0.9 to 1.5)
Hormone therapy26*	81	13.6		84	15.5		0.88 (0.4 to 1.8)

^*Comparison between more intensive and less intensive decision aids.