External validity

External Validity or Clinical Applicability is the validity of generalized (causal) inferences in scientific research, usually based on experiments as experimental validity.

In other words, it is the extent to which the results of a study can be generalized to other situations and to other people.

Mathematical analysis of external validity concerns a determination of whether generalization across heterogeneous populations is feasible, and devising statistical and computational methods that produce valid generalizations.

The reviewer should ask if the results will help doctors care for their patients in the clinical setting. It is important for the reviewer to understand the difference between efficacy and effectiveness of the results.