Table 3. Effect of progesterone on standardized total lesion volume using combined individual animal and summary data, both combined and in predefined subgroups.

Model	Data sets	Animals	SMD	95% CI	Effect P	Inter-action P
Total	18	512	−0.766	−1.173, −0.358	<0.001a
Species
Mice	6	172	−0.492	−0.881, −0.102	0.013	0.44
Rats	12	340	−0.958	−1.539, −0.376	0.001a
Sex
Male	11	291	−1.316	−1.902, −0.730	<0.001a
Female, adult	3	130	0.113	−0.437, 0.662	0.688
Female, agedb	4	91	−0.333	−0.754, 0.088	0.121
Mice
Male	3	108	−0.697	−1.308, −0.086	0.025
Female, adult
Female, agedb
Rats
Male	8	183	−1.547	−2.303, −0.792	<0.001a
Female, adult
Female, agedb
Model
Transient	15	457	−0.549	−0.928, −0.171	0.004a	0.075
Permanent	3	55	−2.058	−3.850, −0.266	0.024a
Treatment time
Before MCAO
After MCAO
Loading dose
Maintenance dose	*
Total dose	*
Randomized
Yes	15	457	−0.674	−1.088, −0.260	0.001a
No	3	55	−1.348	−3.046, 0.350	0.120a
Masked surgery
Yes	5	132	−0.589	−0.946, −0.233	0.001
No	13	380	−0.934	−1.537, −0.332	0.002a
Masked outcome
Yes	7	211	−0.725	−1.134, −0.316	0.001
No	11	301	−0.813	−1.413, −0.213	0.008a
Anesthetic
Isoflurane	8	144	−1.512	−2.324, −0.701	<0.001a
Halothane	8	293	−0.323	−0.700, 0.054	0.093a
Sodium thiopental	1	11	−0.173	−1.363, 1.016	0.775
Ketamine+xylazine	1	64	−0.430	−0.931, 0.064	0.173
Quality
2	1	11	−0.173	−1.363, 1.016	0.775
3	3	56	−1.224	−2.843, 0.395	0.138†
4	3	53	−1.828	−3.824, 0.168	0.073†
5	8	297	−0.534	−1.120, 0.052	0.074†
7	3	95	−0.636	−1.061, 0.211	0.003

Abbreviations: CI, confidence interval; MCAO, middle cerebral artery occlusion; SMD, standardized mean differences.

Data are SMD, 95% CI and significance for effect and interaction. Analyses are adjusted for random effects. Result in bold are statistically significant.

^aHeterogeneity present between studies.

^bHeterogeneity present between ovariectomized.