Table 2 Adjusted association of seven meta-analysis characteristics and the magnitude of BoS in a bivariate meta-analysis
Characteristic | Adjusted effect of characteristic on BoS (full model) | Adjusted effect of characteristic on BoS (after backwards selection) | Final model after applying global shrinkage factor of 0.96 |
|---|---|---|---|
Coefficient (95% CI) p-value | Coefficient (95% CI) p-value | Coefficient | |
Number of studies | 0.70 (0.13 to 1.27) 0.017 | 0.65 (0.19 to 1.12) 0.006 | 0.630 |
Number of studies with outcome of interest | −0.69 (−1.39 to 0.01) 0.052 | −0.79 (−1.38 to −0.19) 0.010 | −0.755 |
Number of studies with both outcomes | −0.23 (−1.20 to 0.74) 0.64 |  |  |
Percentage of studies missing either outcome | −0.12 (−0.53 to 0.28) 0.55 |  |  |
Percentage of studies missing the outcome corresponding to the BoS value | 0.35 (0.09 to 0.61) 0.009 | 0.29 (0.10 to 0.48) 0.003 | 0.282 |
Average absolute within-study correlation | −9.98 (−33.15 to 13.19) 0.39 |  |  |
Largest absolute within-study correlation | 35.23 (12.49 to 57.98) 0.003 | 26.59 (16.53 to 36.65) <0.001 | 25.581 |
Intercept | −13.90 (−23.22 to −4.58) 0.004 | −14.05 (−22.85 to −5.26) 0.002 | −13.020 |
Model performance | Apparent R2= 0.58 | Apparent R2= 0.57 | Optimism-adjustedR2= 0.50 |