Comparison 2. Ring block versus no treatment.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Cry time (by unit)	2	63	Std. Mean Difference (IV, Fixed, 95% CI)	‐1.25 [‐1.80, ‐0.69]
1.1 in %	1	23	Std. Mean Difference (IV, Fixed, 95% CI)	‐2.01 [‐3.05, ‐0.98]
1.2 in seconds	1	40	Std. Mean Difference (IV, Fixed, 95% CI)	‐0.94 [‐1.60, ‐0.29]
2 Heart rate (bpm) change‐from‐baseline	1	23	Mean Difference (IV, Fixed, 95% CI)	‐29.27 [‐52.94, ‐5.60]
3 Oxygen saturation (%) change‐from‐baseline	1	40	Mean Difference (IV, Fixed, 95% CI)	3.84 [‐0.94, 8.62]
4 Respiratory rate (rpm) change‐from‐baseline	1	40	Mean Difference (IV, Fixed, 95% CI)	‐5.69 [‐16.02, 4.64]