Final answer:
Experimental studies can be affected by selection bias and inadequate sample sizes, which can impact their validity.
Step-by-step explanation:
Experimental studies can be affected by several common issues that can impact their validity.
- Selection bias: This occurs when the subjects in the study are not randomly assigned to different treatment groups. For example, if a researcher is studying the effects of a new medication, but only assigns healthier subjects to the experimental group, the results may not accurately represent the general population.
- Sample size: When the sample size is too small, the results may not be reliable or generalizable to a larger population. For instance, in medical testing for rare conditions, it may be challenging to find a large enough sample to draw meaningful conclusions.
By addressing these issues, researchers can improve the validity of experimental studies and ensure that their results are accurate and reliable.