Another simple technique to calculate time difference in Excel is using the TEXT function: 1  Calculate hours between two times: =TEXT(B2-A2, h) 2  Return hours and minutes between 2 times: =TEXT(B2-A2, h:mm) 3  Return hours, minutes and seconds between 2 times: =TEXT(B2-A2, h:mm:ss)
Because cortisol levels change throughout the day, the timing of a cortisol test is important. A cortisol blood test is usually done twice a dayâonce in the morning when cortisol levels are at their highest, and again around 4 p.m., when levels are much lower. Cortisol may also be measured in a urine or saliva test. For a cortisol urine test, your health care provider may ask you to collect all urine during a 24-hour period. This is called a 24-hour urine sample test. It is used because cortisol levels vary throughout the day.
If the adrenal glands are functioning normally, then cortisol levels will rise with the ACTH stimulation. If they are damaged or not functioning properly, then the cortisol level will be low. A longer version of this test (1-3 days) may be performed to help distinguish between adrenal and pituitary insufficiency. cortisol test may be ordered when a person has symptoms that suggest a high level of cortisol and Cushing syndrome, such as. 1  High blood pressure (hypertension). 2  High blood sugar (glucose). 3  Obesity, especially in the trunk. 4  Fragile skin. 5  Purple streaks on the abdomen. 6  Muscle wasting and weakness.