Forest Plot Demonstrating the Quantitative/Qualitative Distinction. Plot showing the results of 14 randomized trials that compared drug-eluting stents (DES) to bare metal stents (BMS) and reported the percentages of patients who underwent target lesion revascularization after stent implantation. Sizes of the squares are proportional to study size, and 95% confidence intervals are shown as horizontal lines. There was unexplained heterogeneity among the trial results, so we did not estimate the size of the difference between groups. However, the random-effects meta-analytic confidence interval at the bottom of the plot showed the summary statistic was statistically significant.