| Intervention focus; subgroup | Meta-analysis, mean difference (95% CI) | Statistical heterogeneity (within group) p value (I2 value, %) | Test for between-group differences p value (I2 value, %) | No. of participants | No. of studies | Quality of evidence rating | ||
|---|---|---|---|---|---|---|---|---|
| Overall | –3.02 (–3.52 to –2.52) | < 0.00001 | (91) | NA | 22 615 | 49 | Moderate | |
| Behavioural | –3.13 (–3.88 to –2.38) | < 0.00001 | (92) | 0.62 | (0) | 10 829 | 33 | Moderate |
| Pharmacologic + behavioural | –2.89 (–3.49 to –2.29) | < 0.00001 | (87) | 11 786 | 17 | Moderate | ||
| Behavioural | ||||||||
| Diet | –4.71 (–6.22 to –3.21) | 0.0003 | (72) | 0.03 | (67.8) | 913 | 8 | Moderate |
| Exercise | –1.49 (–3.32 to 0.35) | 0.0002 | (85) | 598 | 4 | Low | ||
| Diet + exercise | –3.83 (–5.49 to –2.16) | < 0.00001 | (90) | 2 382 | 10 | Low | ||
| Lifestyle | –2.52 (–3.54 to –1.49) | < 0.00001 | (93) | 6 936 | 17 | Low | ||
| ≤ 12 mo duration | –3.43 (–4.32 to –2.55) | < 0.00001 | (88) | 0.07 | (23.4) | 4 780 | 21 | Low |
| > 12 mo duration | –2.53 (–3.81 to –1.24) | < 0.00001 | (95) | 6 049 | 12 | Low | ||
| Male | –4.65 (–6.20 to –3.09) | < 0.00001 | (89) | 0.23 | (31.5) | 2 131 | 8 | Moderate |
| Female | –3.33 (–4.80 to –1.86) | < 0.00001 | (87) | 1 800 | 8 | Moderate | ||
| High cardiovascular disease risk | –1.89 (–2.69 to –1.08) | < 0.00001 | (75) | 0.005 | (87.6) | 2 951 | 12 | Low |
| Low cardiovascular disease risk | –3.66 (–4.59 to –2.74) | < 0.00001 | (92) | 7 878 | 21 | Moderate | ||
| Pharmacologic + behavioural | ||||||||
| Metformin | –1.92 (–2.94 to –0.89) | 0.11 | (60) | 0.07 | (68.8) | 1 938 | 2 | Moderate |
| Orlistat | –3.05 (–3.75 to –2.35) | < 0.00001 | (88) | 9 848 | 15 | Moderate | ||
| ≤ 12 mo | –2.89 (–3.90 to –1.88) | < 0.00001 | (91) | 0.72 | (0) | 4 418 | 11 | Moderate |
| > 12 mo | –2.69 (–3.00 to –2.38) | 0.36 | (9) | 7 368 | 6 | Moderate | ||
| High cardiovascular disease risk | –2.93 (–4.08 to –1.79) | < 0.00001 | (92) | 0.80 | (0) | 3 411 | 9 | Moderate |
| Low cardiovascular disease risk | –2.77 (–3.27 to –2.28) | 0.03 | (54) | 8 375 | 8 | Moderate | ||
Note: CI = confidence interval, NA = not applicable.