Table 2.

Pooled effect sizes for between-group effects across outcomes and moderator variables.

	Sample size		Heterogeneity				Global Effect Sizes
Outcome	K	N	Qa	df	p	I2	Hedges’ gb	95% CI	95% PI	p
Buffering effect (baseline to regulated reactivity)
Combined effects	6	581	4.96	5	.42	0.00	−0.05	−0.20; 0.10	-	.48
Type of strategy - Reappraisal	4	415	2.82	3	.42	0.00	−0.04	−0.25; 0.16	-	.70
Context - Social evaluative	5	493	3.13	4	.54	0.00	−0.01	−0.17; 0.14	-	.86
Type of goal - Down-regulate neg.	6	581	4.96	5	.42	0.00	−0.05	−0.20; 0.10	-	.48
Population - Healthy	6	581	4.96	5	.42	0.00	−0.05	−0.20; 0.10	-	.48
Timing of measurement - 0–30 ​minutes after induction - 30+ minutes after induction	5 4	514 339	6.61 1.41	4 3	.16 .70	39.52 0.00	−0.13− 0.07	−0.35; 0.09− 0.26; 0.12	- -	.24 .48

Note: CI ​= ​confidence intervals, PI ​= ​prediction intervals. ^aFor the Q-statistic, p-values of ​< ​.10 are considered indicative of heterogeneity. ^bEffect sizes are reported as Hedges’ g (standardized mean differences, adjusted for small sample bias) and can be interpreted with reference to the guidelines: <0.3 ​= ​small, 0.5 ​= ​medium and >0.8 ​= ​large [17]. A positive effect size indicates that the active group (i.e., participants instructed to regulate) experienced a larger goal-consistent change in hormones than the control group (i.e., participants not instructed to regulate), while a negative effect size indicates the opposite. Adhering to the principle of independency between effects, effect sizes were combined when studies reported results for more than one measure. Thus, only one effect size per study was used in the analyses.