Alicia is conducting a study on marathon runners by interviewing them at multiple points during the marathon, however, some individuals she interviewed leave the marathon without completing. What threat to internal validity is this?

Question

Quizplus · Accepted Answer

Mortality refers to the loss of participants from a study before it is completed, which can threaten the internal validity by potentially skewing the results if the reasons for leaving affect the outcome measures.

Alicia Is Conducting a Study on Marathon Runners by Interviewing