Alternative visual displays of metaanalysis of malaria treatment trials to facilitate translation of research into policy.

ABSTRACT

Typically, metaanalyses show relative effects and heterogeneity, but not absolute effects-an essential element in policy decision. Data obtained through a systematic review of antimalarial treatment trials and virtual trials were used to generate a display that shows and quantifies absolute and relative effects as well as heterogeneity for comparative trials results. A plot of failure rates (with 95% confidence intervals) of the test drug on the y axis against the risk difference (RD) versus the comparator drug on the x axis is proposed; the area is divided into 4 quadrants by a vertical line (no RD) and a horizontal line (maximum tolerated failures, e.g., 10% for antimalarials). This allows identifying where a drug can be used (meeting efficacy requirements) and quantifying differences (versus another treatment option). The area of the polygon connecting the study points expresses heterogeneity. This graphic display is simple to prepare and interpret and combines in 1 graph both measures of absolute treatment effect and difference, as well as heterogeneity. It may complement current methods and provide useful information in policy decision making.