Table 2. Subgroup analyses for fasting blood glucose and 2-hour blood glucose.

Outcomes	Factors	Subgroup	WMD and 95%CI	p-value	Heterogeneity (%)	p-value for heterogeneity	p-value between subgroups
Fasting blood glucose	Country	Eastern	-0.21 (-0.38 to -0.05)	0.009	0.0	0.482	0.512
		Western	-0.12 (-0.23 to 0.00)	0.054	39.9	0.102
	Mean age (years)	≥ 55.0	-0.21 (-0.30 to -0.12)	< 0.001	0.0	0.597	0.079
		< 55.0	-0.12 (-0.35 to 0.11)	0.317	56.2	0.102
	Percentage male (%)	≥ 50.0	-0.20 (-0.33 to -0.07)	0.003	0.0	0.896	0.484
		< 50.0	-0.10 (-0.29 to 0.10)	0.327	65.8	0.020
	Mean BMI (kg/2)	≥ 30.0	-0.09 (-0.25 to 0.07)	0.255	60.9	0.025	0.627
		< 30.0	-0.22 (-0.35 to -0.08)	0.002	0.0	0.917
	Intervention	Combined	-0.14 (-0.24 to -0.03)	0.009	36.7	0.115	0.229
		Diet	-0.65 (-1.54 to 0.24)	0.152	−	−
		Exercise	-0.45 (-1.00 to 0.09)	0.104	54.5	0.138
	Study quality	High	-0.22 (-0.31 to -0.13)	< 0.001	0.0	0.555	0.062
		Low	-0.06 (-0.23 to 0.11)	0.501	41.1	0.147
2-hour blood glucose	Country	Eastern	-2.23 (-3.27 to -1.19)	< 0.001	−	−	0.002
		Western	-0.51 (-0.91 to -0.11)	0.013	54.5	0.031
	Mean age (years)	≥ 55.0	-0.66 (-0.93 to -0.40)	< 0.001	0.0	0.957	< 0.001
		< 55.0	-1.45 (-2.90 to 0.01)	0.052	79.8	0.026
	Percentage male (%)	≥ 50.0	-1.18 (-1.81 to -0.56)	< 0.001	41.7	0.161	0.010
		< 50.0	-0.32 (-0.89 to 0.25)	0.270	69.6	0.011
	Mean BMI (kg/2)	≥ 30.0	-0.32 (-0.89 to 0.25)	0.270	69.6	0.011	0.026
		< 30.0	-1.32 (-2.20 to -0.45)	0.003	55.6	0.105
	Intervention	Combined	-0.65 (-1.15 to -0.16)	0.010	71.9	0.001	< 0.001
		Diet	-2.48 (-3.58 to -1.38)	< 0.001	−	−
		Exercise	-1.70 (-3.34 to -0.06)	0.043	75.9	0.042
	Study quality	High	-0.64 (-0.92 to -0.37)	< 0.001	0.0	0.928	0.772
		Low	-0.67 (-1.93 to 0.60)	0.301	87.5	< 0.001