Final answer:
The four limitations unavoidable in medical research with human subjects include the impossibility of repeating trials on the same subjects, the potential for inaccurate medical history reporting, the difficulty of controlling all variables, and ethical and privacy considerations.
Step-by-step explanation:
When doing medical research with human subjects, four limitations that are unavoidable include:
- It’s often impossible to repeat trials on the same subjects: In many cases, once the trial has been conducted on a subject, it cannot be repeated due to ethical concerns or other factors.
- Subjects may report an inaccurate medical history: Human subjects may provide inaccurate or incomplete information about their medical history, which can impact the accuracy of the research.
- It can be difficult to control all possible variables: In medical research, there are often numerous variables that can affect the results, and it can be challenging to control all of them.
- There are ethical or privacy concerns to consider: Medical research involving human subjects must prioritize ethical considerations and privacy concerns, which may limit the scope or methods of the research.