Table 1. Summary of results of meta-analysis.

Outcome	Number of studies	Heterogeneity		Meta-analysis model	Standard difference in means	Standard error	95% confidence intervals		p-value
		I2 (%)	p-value				Lower limit	Upper limit
Attention	12	81.69	<0.01*	Random effect	−0.85	0.26	−1.38	−0.33	<0.01*
Delayed recall	16	73.27	<0.01*	Random effect	−1.54	0.22	−1.97	−1.10	<0.01*
Digit span	6	72.80	<0.01*	Random effect	−0.65	0.28	−1.21	−0.10	0.02*
Free recall	7	53.53	0.04*	Random effect	−1.18	0.23	−1.63	−0.73	<0.01*
Immediate recall	11	65.85	<0.01*	Random effect	−1.82	0.26	−2.35	−1.30	<0.01*
Matching to sample	7	86.99	<0.01*	Random effect	−1.76	0.41	−2.57	−0.96	<0.01*
Cognitive function	14	84.59	<0.01*	Random effect	−0.95	0.26	−1.46	−0.44	<0.01*
Complex memory tasks	18	80.57	<0.01*	Random effect	−1.31	0.24	−1.78	−0.84	<0.01*
Recognition	13	84.17	<0.01*	Random effect	−1.84	0.32	−2.48	−1.21	<0.01*

^*Note: Statistically significant.