Table 4.

Leave-one-out sensitivity analyses for key outcomes, showing pooled effect estimates, P-values, and between-study heterogeneity (I²) before and after exclusion of the study that yielded the lowest heterogeneity for each endpoint

Outcome	Effect estimates (before)	P-value (before)	I²% (before)	Study removed in leave-one-out	Effect estimates (after)	P-value (after)	I²% (after)
Incidence of postoperative seroma	RR 0.36	< 0.00001	65%	Awad 2019	RR 0.43	< 0.00001	15%
Need for seroma aspiration	RR 0.29	< 0.00001	30%	Awad 2019	RR 0.34	< 0.00001	0%
Number of seroma aspirations	MD − 1.03	0.0003	95%	Khater 2015	MD − 0.62	0.01	94%
Total drainage volume (mL)	MD − 214.44	0.03	98%	Awad 2019	MD − 167.43	0.02	89%
Duration to drain removal (days)	MD − 2.01	0.22	99%	Awad 2019	MD − 0.96	0.01	56%