FIGURES AND TABLES

Figure 1.

Funnel plot of effect size versus precision of effect size. The figure plots an index of effect size (ln relative risk) against its precision [standard error (SE) of ln relative risk]. There is an absence of small trials that found an increased incidence of contrast nephropathy associated with N-acetylcysteine (NAC).

Figure 2.

Relative risk of contrast nephropathy associated with NAC: All identified trials. Relative risk refers to the risk of contrast nephropathy in the N-acetylcysteine (NAC) group, compared with control. The squares represent the point estimate of relative risk for each study, and their size is proportional to their weight in the pooled estimate of relative risk (represented by the diamond). Bars indicate 95% CI. Q = 26.3, P = 0.02.

Table 1 - Study characteristics.

Table 2 - Study quality.

Table 3 - Results for categorical outcomes.