Power is the probability that a study will reject the null hypothesis. difference between the null and alternative hypotheses. level of significance, and the null vs. alternative difference. a numeric example of power and sample size estimation for the one-sample case.
During the procedure the patient is unconscious and unaware of the need to urinate. After the procedure, however, it may not be safe for the patient to walk. They may be too sick to take care of their own bathroom needs or their surgeon may feel that a catheter is best for their particular recovery.
Indwelling urinary catheters can be used in both men and women. A catheter may be needed because of certain medical conditions, such as an enlarged prostate, the inability to control the release of urine, or after surgery on the pelvis or urinary tract.