Table 4.

Outcomes of the olfactory groove meningioma (OGM): Meta-regression based on age and male percentage. CI - confidence interval, NA – Not available

Outcomes in OGM	Begg’s test (p-value)	Meta-regression on age slope (95% CI)	Meta-regression on age (p-value)	Meta-regression on sex slope (95% CI)	Meta-regression on sex (p-value)
Gross total resection (Simpson Grade 1 Or 2)
Expanded endonasal approach	1	− 0.01 (− 0.02–0.01)	0.45	− 0.3 (− 1.34–0.74)	0.58
endoscope-assisted supraorbital keyhole approach	0.51	0.05 (0.02–0.08)	< 0.01	− 0.28 (− 2.29–1.71)	0.78
Microsopic transcranial approach	0.01	0.01 (− 0.01–0.01)	0.49	− 0.01 (− 0.29–0.28)	0.96
Visual improvement
Expanded endonasal approach	0.04	− 5.07 (− 0.04–0.04)	0.99	0.3 (− 3.3–3.9)	0.87
Endoscope-assisted supraorbital keyhole approach	NA	NA	NA	NA	NA
Microsopic transcranial approach	0.48	0.03 (− 0.06–0.12)	0.55	− 0.47 (− 3.25–2.3)	0.74
Cerebrospinal fluid leak
Expanded endonasal approach	0.64	− 0.002 (− 0.02–0.01)	0.85	0.79 (0.2–1.38)	0.01
Endoscope-assisted supraorbital keyhole approach	NA	NA	NA	NA	NA
Microsopic transcranial approach	0.01	− 0.002 (− 0.009–0.005)	0.51	0.001 (− 0.23–0.23)	0.99
Intra-operative arterial injury
Expanded endonasal approach	0.02	0.001 (− 0.001–0.01)	0.86	0.08 (− 0.29–0.44)	0.68
Endoscope-assisted supraorbital keyhole approach	NA	0 (− 0.008–0.008)	1	0 (− 0.24–0.24)	1
Microsopic transcranial approach	0.01	− 4.56 (− 0.002–0.001)	0.95	− 0.01 (− 0.08–0.05)	0.68
30-day mortality
Expanded endonasal approach	0.01	0 (− 0.01–0.01)	1	0 (− 0.35–0.35)	1
Endoscope-assisted supraorbital keyhole approach	0.01	− 0.001 (− 0.008–0.007)	0.97	− 0.06 (− 0.33–0.21)	0.66
Microsopic transcranial approach	0.01	− 0.001 (-0.003–0.001)	0.07	− 0.09 (− 0.16–0.02)	0.01