Table 3 Stratified analysis of the effects of web-based interventions on weight loss
Variable | Num. of data | Mean difference (95% CI), kg | I2 | P heterogeneity | Significance | Meta-regression |
|---|---|---|---|---|---|---|
Mean age | ||||||
< 45 | 3 | 4.19 (1.89–6.49) | 84.7 | 0.001 | 0.000 | Referent |
≥ 45 | 4 | − 0.06 (− 4.21–4.08) | 0.0 | 0.46 | 0.97 | 0.55 |
Not described | 1 | − 3.11 (− 6.6–0.46) | – | – | 0.088 | |
Duration | ||||||
24 months | 2 | − 0.40 (− 7.58–6.78) | 0 | 0.49 | 0.91 | Referent |
16 months | 2 | 6.82 (4.01–9.63) | 62.6 | 0.102 | 0.000 | 0.50 |
12 months | 4 | − 1.69 (− 4.04–0.65) | 16.5 | 0.31 | 0.15 | 0.46 |
Use of intent-to-treat analysis | ||||||
No | 1 | − 3.1 (− 6.6–0.46) | 0 | – | 0.088 | Referent |
Yes | 7 | 3.19 (1.18–5.21) | 68 | 0.005 | 0.002 | 0.005 |
Interactive web-based intervention | ||||||
No | 4 | − 1.35 (− 4.08–1.36) | 25.3 | 0.26 | 0.33 | Referent |
Yes | 4 | 3.81 (1.53–6.1) | 80.9 | 0.001 | 0.001 | 0.27 |
Drop-out rate | ||||||
< 20% | 7 | 1.97 (0.14–3.81) | 77.5 | 0.001 | 0.03 | Referent |
≥ 20% | 1 | − 1.5 (− 7.48–4.81) | 0 | – | 0.62 | 0.77 |
Included feedback in web-based intervention content | ||||||
No | 3 | 3.37 (1.21–5.54) | 90.2 | 0.000 | 0.002 | Referent |
Yes | 5 | − 1.54 (− 4.52–1.43) | 0 | 0.96 | 0.31 | 0.83 |
Included goal-setting in web-based intervention content | ||||||
No | 4 | 2.79 (0.62–4.96) | 86.5 | 0.001 | 0.012 | Referent |
Yes | 4 | − 0.38 (− 3.3–2.57) | 0.0 | 0.43 | 0.79 | 0.56 |
Jadad score | ||||||
< 2 | 4 | 2.58(0.53–4.63) | 86.5 | 0.001 | 0.014 | Referent |
≥ 2 | 4 | − 0.75 (− 4.11–2.61) | 0 | 0.41 | 0.66 | 0.27 |
Country | ||||||
Others | 3 | − 2.37 (− 4.83–0.09) | 0 | 0.85 | 0.049 | Referent |
USA | 5 | 5.80 (3.32–8.29) | 38.80 | 0.16 | 0.001 | 0.004 |