Question

A surgeon performed two types of surgeries to treat large kidney stones and small kidney stones. Treatment A on large stones was successful 73% of the time, but on small stones it was successful 93% of the time. Treatment B was successful on large stones 69% of the time, but on small stones it was successful 87% of the time. The overall report stated treatment B was more successful. What may make this claim possible? Sampling error Cause-and-effect relationship Convenience error Confounding Simpson's Paradox

Answer 1

Observe that in the question, Treatment A is generally more successful than Treatment B from the information provided. However, the report says that Treatment B is more successful. This is an example of Simpson's Paradox.

Simpson's Paradox is a phenomenon in probability and statistics, whereby a trend appears in several different data groups but will disappear or reverse when these groups are combined.

This result is often encountered in many areas of statistics and is very problematic especially when frequency data is given causal interpretations. The paradox can be resolved when statistical modeling appropriately addresses causal relations.

In the question, it was concluded that treatment B was more successful than treatment A without considering the conditions under which both treatments were carried out neither did it assess the severity of cases of patients involved in the treatment.

SIMPSON'S PARADOX is the correct option.