Meta-regression analysis of effects of prone duration (actually applied in included studies) on mortality. Log odds ratio plotted according to prone duration with the summary fixed-effects meta-regression (z = -1.88; P = 0.06). Each study is represented by a circle proportional to its weight in the meta-analysis reflecting the greatest impact on the slope of the regression line.
Abroug et al. Critical Care 2011 15:R6 doi:10.1186/cc9403