Table 2.

Results of heterogeneity and publication bias estimation and subgroup meta-analysis for risk adverse neonatal outcome among women with gestational diabetes based on various GDM screening strategy group

Outcomesa	GDM classification	Publication biasb	Heterogeneity		Sample size		OR (95% CI)	P value from meta-regression
			I2, %	P value	GDM	Control
SGA	1	0.881	39.2	0.130	21,877	243,938	0.77 (0.66–0.91)	Ref
	2	0.317	81.4	0.021	16,988	352,339	1.03 (0.65–1.62)	0.256
	5	0.458	99.4	0.001	1,204,066	1,912,549	0.74 (0.55–0.98)	0.236
	6	0.174	0	0.988	40,026	851,680	0.90 (0.87–0.94)	0.874
	Overall	0.059	98.4	0.001	1,284,095	3,370,708	0.80 (0.70–0.93)c	-
LGA	1	0.583	85.2	0.001	27,389	284,319	1.90 (1.64–2.21)	Ref
	2	0.602	96.2	0.001	24,712	550,231	1.47 (1.16–1.86)	0.212
	3	0.317	99.4	0.001	8,832	17,514	3.57 (0.39–32.51)	0.365
	5	0.024c	99.9	0.001	1,209,604	1,977,988	2.17 (1.43–3.29)	0.845
	6	0.624	96.7	0.001	40,123	853,787	2.11 (1.38–3.24)	0.365
	7	0.602	9.1	0.335	618	16,783	1.49 (1.05, 2.11)	0.965
	Overall	0.000c	99.6	0.001	1,311,278	3,700,622	2.02b (1.67–2.43)c	-
Macrosomia	1	0.464	86	0.001	29,846	315,420	1.59 (1.35–1.89)	Ref
	2	1.000	76.3	0.006	1,058	4,480	0.72 (0.39–1.33)	0.251
	4	0.317	87.5	0.005	497	13,938	1.36 (0.42–4.37)	0.452
	5	1.000	98.4	0.001	54,351	1,090,454	1.94 (1.51 –2.49)	0.369
	6	0.317	90.7	0.001	40,641	856,341	1.57 (1.28 –1.93)	0.569
	7	0.497	73.9	0.009	2,779	58,909	1.36 (0.97–1.90)	0.854
	Overall	0.445	96.2	0.009	129,200	2,340,286	1.62 (1.43–1.82)c	-
Hyperbilirubinemia	1	0.188	14.4	0.322	8,333	30,103	1.17 (1.07–1.28)	Ref
	5	1.000	64.4	0.024	8,382	117,060	1.37 (1.12–1.68)	0.526
	6	0.317	93.4	0.001	539	2,931	2.82 (0.63–12.60)	0.687
	Overall	0.458	90.7	0.001	25,309	158,016	1.51 (1.22–1.86)c	-
Stillbirth	1	0.458	54.7	0.031	24,625	425,869	0.71 (0.46–1.09)	Ref
	2	0.602	0	0.381	17,596	354,011	1.13 (0.87–1.48)	0.251
	3	0.317	0	0.999	8,028	8,385	2.35 (1.87, 2.97)	0.236
	4	0.317	93.2	0.001	497	13,938	2.19 (0.00–1,045.39)	0.028c
	5	0.805	71.7	0.001	33,075	638,980	1.14 (0.77–1.69)	0.017c
	6	0.602	0	0.634	3,044	114,961	0.94 (0.49–1.79)	0.258
	Overall	0.662	79.3	0.001	87,122	1,572,317	1.07 (0.79–1.45)	-
RDS	1	0.117	0	0.396	2,737	9,068	1.60 (1.18–2.15)	Ref
	5	0.327	55.2	0.063	19,448	320,395	1.41 (1.10–1.80)	0.256
	6	0.317	68.8	0.073	539	2,931	1.60 (0.24–10.49)	0.854
	Overall	0.586	44	0.057	22,779	332,675	1.51 (1.23–1.85)c	-
NICU admission	1	0.245	90.3	0.001	9,010	33,321	1.70 (1.25–2.30)	Ref
	2	0.497	55.5	0.081	25,320	551,903	1.27 (1.10–1.47)	0.258
	5	0.621	82.4	0.001	56,767	821,862	1.66 (1.54–1.79)	0.369
	Overall	0.280	89.2	0.001	92,166	1,413,849	1.69 (1.54–1.85)c	-
Neonatal hypoglycemia	1	1.000	75.2	0.003	7,038	24,824	4.16 (2.42–7.17)	Ref
	5	1.000	97.9	0.001	8,270	115,911	2.78 (0.57–13.50)	0.523
	Overall	0.186	97.4	0.001	32,132	492,775	4.84 (3.24–7.25)c	-
Preterm	1	0.105	80.2	0.001	45,839	521,248	1.32 (1.18–1.48)	Ref
	2	1.000	95.6	0.001	25,446	551,903	1.21 (0.88–1.68)	0.254
	5	0.910	99.7	0.001	1,453,641	6,040,151	1.61 (1.29–2.00)	0.165
	6	0.174	92.8	0.001	40,104	853,434	1.09 (0.82–1.46)	0.895
	7	0.602	42.7	0.175	618	16,783	1.95 (1.07–3.56)	0.207
	Overall	0.166	99.3	0.001	1,565,607	7,985,935	1.42 (1.25–1.60)c	-
Birth trauma	1	1.000	0	0.443	7,178	24,780	1.45 (1.24–1.69)	Ref
	2	0.317	89.6	0.002	24,451	547,825	1.28 (1.00–1.66)	0.257
	5	0.652	78.2	0.001	124,428	1,718,553	1.57 (1.24–2.00)	0.584
	6	0.317	72	0.059	539	2,931	1.34 (0.10–17.81)	0.985
	Overall	0.368	88.1	0.001	156,596	2,294,089	1.51 (1.25–1.83)c	-

GDM, gestational diabetes mellitus; OR, odds ratio; CI, confidence interval; SGA, small for gestational age; LGA, large for gestational age; RDS, respiratory distress syndrome; NICU, neonatal intensive care unit.

^aAll subgroups analyses did not performed due to lack of available data,

^bObtained from trim and fill method,

^cStatistically significant level P<0.05.