To compare outbreak curves accurately, which practice is essential when presenting multiple charts?

• A. Label axes clearly and use the same scale across charts.
• B. Use different scales to exaggerate differences.
• C. Omit axis labels.
• D. Change units between charts.

Answer: (A)

Comparing outbreak curves accurately comes down to presenting them with a consistent visual frame. When multiple charts are shown, labeling the axes clearly and keeping the same scale across charts ensures that any differences you observe reflect real differences in the data, not plotting choices. A common y-axis range (and same x-axis units, like days) lets you see whether one outbreak grows faster, peaks higher, or lasts longer, without being misled by a chart that uses a larger or smaller scale.

If scales differ, differences can be exaggerated or hidden, which distorts interpretation. Omitting axis labels removes essential context, making it impossible to know what’s being measured or the units. Changing units between charts disrupts comparability entirely.

So, clear axis labeling plus the same scale across charts is essential for an honest, interpretable comparison.