. 2022 Dec 20;23(12):413. doi: 10.31083/j.rcm2312413

Table 3.

Subgroup analysis.

Subgroup		Number	SMD	95% CI		Weight %	p value	Heterogeneity
Species
	Rats	39	–2.328	–2.775	–1.881	87.77	$<$ 0.001	72.20%
	Mice	6	–2.983	–4.145	–1.82	12.23	$<$ 0.001	67.10%
Anesthesia
	Inhalation	4	–2.005	–2.878	–1.131	9.54	$<$ 0.001	38.60%
	Injection	40	–2.473	–2.935	–2.011	87.96	$<$ 0.001	73.80%
	Unclear	1	–1.86	–3.186	–0.534	2.5	0.006	NA
I/R method
	Ex vivo	10	–3.638	–4.765	–2.512	18.94	$<$ 0.001	73.60%
	In vivo	35	–2.118	–2.539	–1.697	81.06	$<$ 0.001	68.10%
Reperfusion duration
	1–1.5 h	8	–2.368	–3.701	–1.036	18.05	$<$ 0.001	84.90%
	2–3 h	33	–2.462	–2.924	–2.001	72.92	$<$ 0.001	68.10%
	24 h	4	–1.911	–2.863	–0.958	9.02	$<$ 0.001	44.10%
RIPC site
	Limb	22	–2.462	–3.046	–1.879	47.64	$<$ 0.001	70.00%
	Hepatic vessel	2	–3.354	–8.103	1.395	3.58	0.166	87.00%
	Femoral artery	15	–2.445	–3.055	–1.834	34.06	$<$ 0.001	59.60%
	Infrarenal aorta	3	–1.216	–3.411	0.978	7.18	0.277	87.20%
	Mesenteric artery	2	–3.151	–4.621	–1.681	4.88	$<$ 0.001	55.30%
	Abdominal aorta	1	–1.891	–3.049	–0.732	2.67	0.001	NA
RIPC duration
	5/5 min	38	–2.365	–2.775	–1.954	83.83	$<$ 0.001	65.40%
	5/15 min	1	–0.451	–1.517	0.615	2.76	0.407	NA
	10/10 min	1	–3.734	–5.297	–2.171	2.27	$<$ 0.001	NA
	15/15 min	4	–3.404	–4.279	–2.528	8.44	$<$ 0.001	9.90%
	30/15 min	1	0.548	–0.571	1.668	2.7	0.337	NA
RIPC cycles
	1 cycle	8	–2.177	–3.51	–0.844	18.84	0.001	86.20%
	3 cycles	22	–2.474	–2.98	–1.969	49.54	$<$ 0.001	62.20%
	4 cycles	15	–2.356	–3.073	–1.638	31.63	$<$ 0.001	67.30%
Staining method
	TTC	12	–2.556	–3.287	–1.825	25.06	$<$ 0.001	59.00%
	TTC-Evans blue	30	–2.095	–2.549	–1.64	70.53	$<$ 0.001	69.20%
	TTC-patent blue	2	–7.098	–10.528	–3.668	2.57	$<$ 0.001	65.30%
	TTC-black Chinese ink	1	–3.515	–5.57	–1.459	1.84	0.001	NA

Abbreviation: RIPC, remote Ischemic preconditioning; I/R, ischemia/reperfusion; TTC, 2,3,5-Triphenyltetrazolium chloride; SMD, standardized mean difference; CI, confidence interval; NA, not available.