Table 1.

Overall and subgroup (<12 and ≥12 years) analyses of BMI and BMI Z score differences.

Outcome, follow-up	Number of studies	Number of participants	Meta-analyses, mean difference (95% CI)	Statistical heterogeneity		Test for differences between subgroups		GRADE quality of overall documentation
Overall Subgroups				P value	I 2 value	P value	I 2 value
BMI 6 months	14	1591	−0.99 (−1.36 to −0.61)	0.00001	72%	—	—	Moderate1
Age < 12 years	6	896	−0.74 (−0.26 to −0.22)	0.0006	77%	0.19	40.8%
Age ≥ 12 years	8	695	−1.26 (−1.85 to −0.68)	0.001	70%
BMI 12 months	19	3238	−0.67 (−1.01 to −0.32)	<0.00001	80%	—	—	Moderate1
Age < 12 years	10	2135	−0.31 (−0.45 to −0.17)	0.47	0%	0.13	55.7%
Age ≥ 12 years	9	1103	−1.02 (−1.95 to −0.10)	<0.00001	87%
BMI 24 months	8	828	−0.96 (−1.63 to −0.29)	0.005	65%	—	—	Low1,2
Age < 12 years	3	254	−0.28 (−0.85 to 0.30)	0.26	25%	0.007	86.3%
Age ≥ 12 years	5	574	−1.58 (−2.33 to −0.83)	0.18	36%
BMI Z score 6 months	18	1607	−0.12 (−0.17 to −0.06)	<0.00001	77%	—	—	Moderate1
Age < 12 years	9	696	−0.16 (−0.27 to −0.05)	<0.00001	79%	0.35	0%
Age ≥ 12 years	9	911	−0.10 (−0.16 to −0.03)	<0.0001	77%
BMI Z score 12 months	22	2804	−0.16 (−0.21 to −0.10)	<0.00001	69%	—	—	Moderate1
Age < 12 years	11	1504	−0.17 (−0.26 to −0.07)	0.0006	68%	0.91	0%
Age ≥ 12 years	11	1300	−0.16 (−0.23 to −0.09)	0.0002	71%
BMI Z score 24 months	8	831	−0.16 (−0.21 to −0.10)	0.17	33%	—	—	High
Age < 12 years	3	257	−0.13 (−0.26 to 0.00)	0.09	58%	0.56	0%
Age ≥ 12 years	5	574	−0.17 (−0.23 to −0.11)	0.28	21%

¹High statistical heterogeneity, ²wide confidence interval.