Nicolle 1987.

Methods	Study design: parallel RCT Duration of study: not reported Duration of follow‐up: 1 year
Participants	Country: Canada Setting: nursing facility Inclusion criteria: elderly institutionalised women Definition of ASB: ≥ 100,000 CFU/mL on 2 consecutive urine cultures with same 1‐2 pathogens. When more than 2 pathogens, catheter specimens were compared to voided specimens for confirmation Number: treatment group (26); control group (26) Mean age ± SD (years): treatment group (83.3 ± 8.7); control group (83.6 ± 9.0) Sex (M/F): all women Exclusion criteria: long‐term indwelling catheters; unable to provide reliable voided specimens
Interventions	Treatment group 1st course TMP/SMX or ampicillin: single dose 2nd course (for failure) An alternate oral agent for 2 weeks 3rd course (for failure) Aminoglycoside, indanyl carbenicillin nitrofurantoin, amikacin, cefaclor, TMP, cephalexin for 6 weeks Control group No treatment
Outcomes	Morbidity Mortality Bacteriological cure Definition of bacteriological cure: no recurrence for the initial bacteriuria after single‐dose or 2 weeks treatment Resistance development Adverse events
Notes	Most E. coli Urine cultures at 1 and 4 weeks post‐treatment and monthly for the control and treatment groups without post‐treatment culture groups Urine culture could not be obtained for at least 1 month from 12 in the treatment group and 9 in the control group Grant from Foothills Hospital Research and development fund and Alberta Heritage Foundation for Medical Research
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomly assigned, random numbers table
Allocation concealment (selection bias)	Unclear risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	High risk	Open‐label study
Blinding of outcome assessment (detection bias) All outcomes	High risk	Open‐label study
Incomplete outcome data (attrition bias) All outcomes	Low risk	Loss to follow‐up described; treatment group (discharged at 2 (1), 5 (1) and 11 (1) months; died (9)); control group (uninterpretable urine specimens and excluded post‐randomisation (2); discharged at 10 months (1); long‐term indwelling catheter at 4 months of study (1); died (4))
Selective reporting (reporting bias)	Low risk	Not observed
Other bias	Unclear risk	Funding

ADL‐ activities of daily living; ASB ‐ asymptomatic bacteriuria; CFU ‐ colony forming units; ITT ‐ intention to treat; RCT ‐ randomised controlled trial; TMP ‐ trimethoprim; SMX ‐ sulfamethoxazole; UTI ‐ urinary tract infection