Table 1.

Characteristics of the groups of trials.

Group	N	Delay (min)	Duration (min)
<33℃	23	37 ± 46	413 ± 784
33–34℃	34	36 ± 56	284 ± 385
>34℃	16	48 ± 66	811 ± 966
Intra-carotid saline	11	68 ± 68	97 ± 207
Local cooling device	7	79 ± 124	114 ± 97

For comparison to prior studies—which primarily focused on infarction volume compared among trials—we summarized the key properties of the trials from which we extracted normalized mean differences in infarction volume. We included 91 unique comparisons. Studies of whole body cooling (surface or pharmacological) were grouped according to the targeted body temperature. Studies that used intracarotid cold saline or skull/dural local cooling devices were grouped separately. The mean ± SD delay time (delay from ischemia onset to start of cooling) and the duration of cooling are summarized. Using one-way ANOVA and Tukeys HSD post-hoc test, we found no significant differences among the groups, although the duration of intra-carotid hypothermia was nominally shorter than the whole body cooling groups. All results are given as mean ± SD