The four limitations are
1.It's often impossible to repeat trials on the same subjects.
2-Subjects may report an inaccurate medical history.
3-It can be difficult to control all possible variables.
4-It's impossible to come up with testable scientific questions for human subjects.
Research involving human beings is ultimately necessary for improvements in human health and welfare. Any results about healthy physiology, illness causes, treatment effectiveness, learning, or behavior must be verified by carefully controlled investigations involving human participants. Sadly, not all human research have been valid and beneficial. It is possible to harm people in the name of research. The most well-known instances happened in Nazi Germany. Investigations conducted after the war found several crimes, including experiments in which participants were submerged in extremely cold water to determine how long it would take them to pass away from hypothermia.
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The correct codes are 63267 and 69990.
The codes are given based on the lesion if it is intradural or extradural. In our case here it is extradural cystic structure so that is why it ranges between 63265 to 63268.
We also divide the section of spine depending on where the lesion is being located. Code 63267 describes laminectomy which has evacuation of intraspinal lesion which is found in the lumbar spine.
69990 code documents the use of microscope.
