Adhering to the clinical research protocols will always acquire the right results. In this Study, Upton has shown that if ANI is maintained between 50 and 70, the pain scores of your patients will be dramatically reduced. This decreases postoperative pain levels, as well as, the side effects related to opioid overdosing. On the other hand, in Szental study, he was unable to show these results as the researchers did not adhere to the protocol which resulted in an incorrect conclusion.