Table 4.

Moderator analysis results for methodological variables.

Variable	Level	d	95% CI	k
Study source	Journal article	.28	[.21, .35]	226
	Other	.32	[.00, .63]	22
Institution of first author	University or college	.29	[.21, .36]	228
	Research center	.25	[−.05, .55]	14
Sampled population	General population	.14	[.00, .29]	45
	University students	.34	[.24, .43]	145
	High school students	.35	[.09, .60]	17
	Children	.25	[−.03, .53]	13
	Other	.18	[−.04, .39]	24
Participants run in groups	Yes	.30	[.21, .38]	135
	No	.32	[.20, .43]	75
Study setting	Laboratory	.25	[.15, .35]	137
	Field	.31	[.22, .41]	107
Message specificity	Single specific target	.30	[.22, .39]	182
	Multiple specific targets	.22	[.02, .42]	26
	Multiple non-specific targets	.26	[.10, .42]	35
Measured fear in the study	Yes	.30	[.18, .41]	71
	No	.28	[.20, .36]	177
Media of message	Text information	.36	[.25, .47]	93
	Pictures/videos	.20	[.09, .31]	73
Health related message	Yes	.28	[.20, .35]	202
	No	.31	[.13, .49]	43
Study domain	Dental hygiene	.06	[−.16, .28]	14
	Driving safety	.11	[−.10, .33]	27
	HIV/STDs	.37	[.20, .54]	33
	Drinking/drugs	.49	[.25, .74]	20
	Smoking	.26	[.13, .40]	40
	Cancer prevention	.16	[−.01, .34]	26
	Disease prevention	.40	[.19, .61]	51
	General safety	.22	[.03, .40]	13
	Environment/society	.24	[.02, .45]	13
	Other	.39	[.11, .68]	11

Note: d = Standardized mean effect size estimated meta-analytically for the indicated moderator level. 95% CI = The 95% confidence interval for d. k = The number of studies for each moderator level.