Table 1 Summary of each study included in the comparison

Westra et al. [ 32]

5,311

Peripheral blood

4,909

33

14,586

Colantuoni et al. [26]

269

Prefrontal Cortex

455

2

30,176

Gibbs et al. [7]

150

Caudal Pons

997

278

5

22,184

Cerebellum

318

Frontal Cortex

331

Temporal Cortex

385

Heinzen et al. [10]

93

Frontal Cortex

52

< 1

~22,000

Kim et al. [27]

165

Cerebellum, Frontal Cortex, Thalamus, Temporal Cortex

648

211

*

Hippocampus, Frontal Cortex

594

Liu et al. [28]

127

Prefrontal Cortex

1,063

15

Myers et al. [31]

193

Cortex (Pooled data from 20% frontal, 70% temporal and 1% parietal)

2,975

19

Webster et al. [29]

364

Cortex (Pooled from 21% frontal, 73% temporal, 2% parietal and 3% cerebellar)

743

9

8,650

Cortex (Pooled from 18% frontal, 60% temporal, 10% parietal and 13% cerebellar)

Zou et al. [30]

374

Cerebellum

686

3

24,526