Comparison 1. Herbal medicine versus placebo.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Normalisation of fasting blood glucose (< 7.2 mmol/L)	5	448	Risk Ratio (M‐H, Fixed, 95% CI)	2.03 [1.39, 2.98]
1.1 Huoxue Jiangtang Pingzhi formula versus placebo	1	60	Risk Ratio (M‐H, Fixed, 95% CI)	1.67 [0.69, 4.00]
1.2 Liuwei Dihuang Tang versus placebo	1	60	Risk Ratio (M‐H, Fixed, 95% CI)	1.17 [0.44, 3.06]
1.3 Qidan Tongmai tablet versus placebo	1	128	Risk Ratio (M‐H, Fixed, 95% CI)	2.28 [1.02, 5.12]
1.4 Xianzhen Pian versus placebo	3	200	Risk Ratio (M‐H, Fixed, 95% CI)	2.5 [1.38, 4.54]
2 Fasting blood glucose levels (mmol/L)	10		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.1 Bauhinia forficata extracts versus placebo	1	16	Mean Difference (IV, Fixed, 95% CI)	‐0.20 [‐2.76, 2.36]
2.2 Ginseng versus placebo	1	36	Mean Difference (IV, Fixed, 95% CI)	‐0.80 [‐1.64, 0.04]
2.3 Holy basil versus placebo	1	40	Mean Difference (IV, Fixed, 95% CI)	‐1.30 [‐1.92, ‐0.68]
2.4 Huoxue Jiangtang Pingzhi formula versus placebo	1	60	Mean Difference (IV, Fixed, 95% CI)	‐1.10 [‐1.63, ‐0.57]
2.5 Inolter versus placebo	1	60	Mean Difference (IV, Fixed, 95% CI)	‐1.47 [‐3.47, 0.53]
2.6 Liuwei Dihuang Tang versus placebo	1	60	Mean Difference (IV, Fixed, 95% CI)	1.0 [0.41, 1.59]
2.7 Myrcia uniflora extracts versus placebo	1	18	Mean Difference (IV, Fixed, 95% CI)	0.5 [‐3.89, 4.89]
2.8 Qidan Tongmai tablet versus placebo	1	128	Mean Difference (IV, Fixed, 95% CI)	‐0.35 [‐0.89, 0.19]
2.9 TCT versus placebo	1	104	Mean Difference (IV, Fixed, 95% CI)	‐0.22 [‐0.36, ‐0.08]
2.10 Xianzhen Pian versus placebo	3	200	Mean Difference (IV, Fixed, 95% CI)	‐0.85 [‐1.64, ‐0.05]
3 Glycated haemoglobin levels (%)	4		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
3.1 Ginseng versus placebo	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
3.2 Inolter versus placebo	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
3.3 Qidan Tongmai tablet versus placebo	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
3.4 TCT versus placebo	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
4 Fasting serum insulin levels (mU/L)	2		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
4.1 Ginseng versus placebo	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
4.2 Huoxue Jiangtang Pingzhi formula versus placebo	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
4.3 Liuwei Dihuang Tang versus placebo	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]