Table 3

 Quality of case–control studies examining the effect of circumcision on urinary tract infection in male subjects

ReferenceDefinition of UTIDetermination of circumcision statusExclusion criteriaOrigin of controlsAdjustment for confounding variables
CSU, catheter specimen of urine; MSU, midstream urine; SES, socioeconomic status; SPA, suprapubic aspirate; UTI, urinary tract infection.
Newman et al24Bag urine or clean catch ⩾107/lStandard questionnaireNo fever >38°C or urine collected at presentationPatients presenting to non-hospital outpatients with a feverNoNoNo
CSU ⩾2×106/lUncertain circumcision status
SPA ⩾104/l
Craig et al23CSU/SPA ⩾106/lDirect questioning of parents or direct examinationPast history of UTI or urinary tract abnormality; neurological or skeletal abnormality predisposing to UTIPatients presenting to hospital emergency department for any reason other than those diagnosed with UTIYesNoNo
MSU ⩾108/l
Rushton and Majd25MSU ⩾108/lCases: “prospectively” found but not specifiedProlonged neonatal hospital admission or uncertain circumcision statusPatients admitted with febrile upper respiratory tract infection. Matched for age, race, and SESNoYesYes
CSU ⩾107/lControls: documentation in medical record but no further details given
Spach et al26MSU >106/l growth along with one or more symptomsExaminationNo clear exclusion criteriaPatients without bacteriuria presenting to outpatient clinicYesNoYes
Crain and Gershel27Bag urine ⩾104/lDocumentation in medical records no further details givenAbsence of feverPatients presenting to hospital with fever and without a discharge diagnosis of UTINoNoNo
CSU ⩾104/l
SPA ⩾102/l
Kashani and Faraday28CSU/SPA ⩾108/lDocumentation in medical recordUrinary tract abnormality, inadequate documentation of specimen type or age <1 monthPatients presenting to outpatients clinics for unrelated reasonsNoNoYes
Herzog29CSU/SPA ⩾107/lDocumentation in medical record or direct contact with family if unclear in medical recordsAnatomical abnormality, past history of UTI, myelodysplasia, uncertain circumcision status or race, and equivocal culture resultsPatients who presented to emergency with a febrile illness and had a SPA or CSU which was negativeYesYesYes