Urodynamic testing or urodynamics refers to a group of tests that assess how the bladder and urethra perform their job of storing and releasing urine. Urodynamic tests evaluate lower urinary tract function by measuring urinary flow and pressure during bladder filling and voiding. Urodynamic tests can help explain symptoms such as:incontinence frequent urination sudden, strong urges to urinate but nothing comes out problems starting a urine stream painful urination problems emptying the bladder completely recurrent urinary tract infections