Foley 1987.

Methods	Randomised trial, 2 parallel groups.
Participants	Inclusion: bacteriuric (> 100,000 bacteria/mL x 1; midstream urine) at first prenatal visit. Setting: Dublin, Ireland Number of participants: N = 220
Interventions	Sulphamethizole 300 mg or nitrofurantoin 150 mg daily x 3 days (based on susceptibility of the organism); re‐treatment or maintenance treatment as necessary (N = 100). Control group received no treatment (N = 120)
Outcomes	Persistent bacteriuria (at follow‐up, not defined further) Pyelonephritis, only reported as 'admitted with pyelonephritis', no definition provided
Notes	Description of study provided in letter to editor; no publication Dates of study: 1985 Funding sources: not stated Declarations of interest: none reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Allocated to treatment or no treatment by "toss of a coin".
Allocation concealment (selection bias)	Unclear risk	No information was provided to permit judgement.
Blinding of participants and personnel (performance bias) All outcomes	High risk	No description of any attempt at blinding; not placebo‐controlled.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No description of any attempt at blinding; not placebo‐controlled.
Incomplete outcome data (attrition bias) All outcomes	High risk	Loss to follow‐up: 19%; no reasons provided for missing outcome data on these women
Selective reporting (reporting bias)	High risk	No pregnancy outcomes (gestational age, birthweight)
Other bias	Low risk	The study appears to be free of other sources of bias.
Overall Risk of Bias	High risk	Judged at overall high risk of bias