Table 2.
Moderators in the meta‐regression
| Moderator | Range or values | Estimate from MR (SE) | p‐Value from MR |
|---|---|---|---|
| Flow rate (N) | 0.1–3 μL/min | −0.74 (0.19) | < 0.001 |
| Probe surface area (N) | 0.24–2.84 mm2 | 0.13 (0.32) | 0.681 |
| Anaesthesia (C) | None, injection, inhalation, combined (injection & inhalation) | < 0.001 | |
| Injection versus none | 2.51 (0.44) | < 0.001 | |
| Inhalation versus none | 1.50 (0.43) | 0.008 | |
| Combined versus none | 2.13 (0.78) | 0.008 | |
| Species (C) | Cat, mouse, pig, rat, sheep | 0.672 | |
| Cats versus rats | 1.37 (1.02) | 0.186 | |
| Mice versus rats | 0.35 (0.84) | 0.677 | |
| Pigs versus rats | 0.74 (0.90) | 0.414 | |
| Sheep versus rats | 0.18 (0.91) | 0.840 | |
| Brain region (C) | Basal forebrain, brainstem, cortex, hippocampus, thalamusa | 0.145 | |
| Brainstem versus basal forebraina | −0.98 (0.68) | 0.153 | |
| Cortex versus basal forebraina | −0.26 (0.62) | 0.682 | |
| Hippocampus versus basal forebraina | 0.74 (0.50) | 0.145 | |
| Thalamus versus basal forebraina | 0.76 (0.66) | 0.253 |
N, numerical moderator; C, categorical moderator; MR, meta‐regression.
a
Refer to the methods section for information on pooling of brain regions.