Doctors use uroflowmetry to test the amount of urine voided during urination. It also measures the speed of urination. The test is called a uroflow test. It can helps doctor identify the causes of certain urinary difficulties. The doctor may recommend a uroflow test if patient have slow urination, a weak urine stream, or difficulty urinating. They may also use it to test his sphincter muscle. The sphincter muscle is a circular muscle that closes tightly around the bladder opening. It helps to prevent urine leakage. Results from the test can help his doctor determine how well patient bladder and sphincter are functioning.