Based on this data, the researchers conclude that early p41 treatments decrease the length of Ebola virus disease.

Does the data in the graph show causation or correlation between p41 treatment and the length of Ebola disease?

The data in the graph shows a correlation between p41 treatment and the length of Ebola virus disease. While the researchers may conclude that early p41 treatments decrease the length of the disease based on the data shown, it does not prove causation. There could be other factors at play that are influencing the results. Further studies would be needed to establish a causal relationship.