. 2023 Sep 19;46(1):251. doi: 10.1007/s10143-023-02153-7

Table 2.

A comparison of drainage versus no drainage after burr-hole evacuation of chronic subdural hematoma with previous published studies

	Our study	Peng and Zhu [10]	Alcalá-Cerra et al. [25]	Liu et al. [26]
No. of patient	1961	968	628	273
No. of studies	10	9	7	4
Recurrence	Favor drainage
Recurrence	OR = 0.39, 95% CI 0.28 to 0.55, P < 0.00001, I² = 0%	RR = 0.45, 95% CI 0.32 to 0.61, P < 0.0001, I² = 38%	RR = 0.51, 95% CI 0.36 to 0.75, P = 0.0005	OR = 0.36, 95% CI 0.21–0.60, P < 0.001, I² = 0
	Favor drainage	Insignificant
Mortality	OR = 0.65, 95% CI 0.43 to 0.97, P = 0.04, I² = 0%	RR = 0.78, 95% CI 0.45 to 1.33, P = 0.35, I² = 22%	RR = 0.67, 95% CI 0.37 to 1.22, P = 0.19, I² = 18%	OR = 0.99, 95% CI 0.45 to 2.16, P = 0.98, I² = 0
	Favor drainage	Insignificant	Favor drainage
Poor functional outcomes	OR = 0.58, 95% CI 0.37 to 0.89, P = 0.01, I² = 0%	RR = 0.68, 95% CI 0.44 to 1.05, P = 0.08, I² = 31%	RR = 0.61, 95% CI, 0.39 to 0.98, P = 0.04, I² = 1	-
		Insignificant
Complication	-	RR = 1.15, 95% CI 0.77 to 1.72, P = 0.5, I² = 0%	RR = 1.28, 95% CI 0.78 to 2.11, P = 0.33, I² = 0%	OR = 1.6, 95% CI 0.92 to 2.78, P = 0.09, I² = 1