instruction: calculate the number of patients who have received a urine, voided specimen microbiological test in the last year.
response: SELECT COUNT(DISTINCT patient.uniquepid) FROM patient WHERE patient.patientunitstayid IN (SELECT microlab.patientunitstayid FROM microlab WHERE microlab.culturesite = 'urine, voided specimen' AND DATETIME(microlab.culturetakentime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year'))