Diamond Mean Comparison Charts

In these charts, the horizontal dashed line is the overall mean. The line through the center of each diamond is the group mean. The top and bottom diamond vertices are the respective upper and lower 95% confidence limits (CI) about the group mean. The short horizontal lines flanking the means are overlap marks.

• In groups with equal sample sizes, overlapping marks indicate that the two group means are not significantly different at the 95% confidence level.
• The X-axis tick intervals can be equally spaced, or displayed proportional to the sample size.

• These diamond charts can be used for data layouts where responses from different groups are stored in the same data column, and a grouping variable is used to split the data.