The Effectiveness of Aromatherapy in Reducing Pain: A Systematic Review and Meta-Analysis

Figure 2

Publication bias funnel plot. A funnel plot was used to assess risk of publication bias. A symmetrical funnel plot is an indicator for lack of bias in a meta-analysis. A funnel plot loses its utility with a cut-off of 10 studies and this analysis included only 12. The funnel plot for this final analysis was not fully symmetrical, but publication bias cannot be concluded based on the small sample size and heterogeneity of studies. The diagonal lines represent the limits of 95% confidence. Because strict 95% limits are not reported, they are referred to as “pseudo 95% confidence limits.”