Interpretation of urinary flow rates.

The uroflow examination is the most accurate, physiologic, and noninvasive method of assessing bladder outflow obstruction. The examiner must be aware of the errors that may arise from problems inherent in the uroflowmeter, in the patient (such as psychological inhibition), or in bladder physiology (such as the influence of intravesical volume). Additional tests such as pressure-flow studies or simple cystometry are required in certain cases.