COMPLETE QUESTION:
A college health center identifies lack of testicular self-examination among students and implements an intense summer wellness program focusing on the benefits of testicular self-examination. Afterward, a count indicates an increased number of students who do not complete testicular self-examinations.
Which internal validity threat is suspected?
A. History
B. Maturation
C. Testing
D. Mortality
E. Selection bias
ANSWER: (D) MORTALITY
EXPLANATION:
Internal validity is the degree to which a control or piece of evidence backs a claim or decision about a result, during the process of an experiment or study.
The degree of control incorporated over potential overstated variables describes the level of internal validity and about eight (8) effects of internal validity had been described.
However, in the above scenario (where count indicates an increased number of students) depicts a MORTALITY in the study.
This effect occurred as a result of inference made on the basis of only those students that have participated from the beginning to the end of the experiment or study. Presumably, students may have dropped out of the study before completion, and other possible reasons.