Jimenez‐Pacheco 2012.

Methods	Study design: unblinded, randomized, controlled study Study dates: March–August 2011 Setting: Urology Department, Santa Ana Hospital de Motril Country: Spain
Participants	Inclusion criteria: diagnostic flexible cystoscopy indication, aged ≥ 18 years Exclusion criteria: antibiotic administration for any reason during the previous month; urethral catheterization during previous month or at the moment of intervention; history of UTI during previous month; positive culture; pregnancy; ≥ 2 UTI episodes during last 3 months; obstructive uropathy diagnosis with residual urine > 100 mL; unilateral or bilateral vesicoureteral reflux; neurogenic bladder or any lower urinary system malformation; intermittent or urethral permanent catheterization; risk of endocarditis (participants with prosthetic cardiac or vascular valves, etc); and hypersensitivity to fosfomycin Sample size: 60 participants Age (years): mean: control group: 65.4; treatment group: 64.6 Sex: 27 men and 3 women in control group; 25 men and 5 women in treatment group
Interventions	Group 1 (n = 30): no antibiotics after flexible cystoscopy Group 2 (n = 30): oral single dose of fosfomycin trometamol 3 g during 2 hours prior to test
Outcomes	Symptomatic UTI How measured: 10 days after cystoscopy, urine culture and urinalysis performed, bacteriuria considered when > 105 CFU/mL were recorded in urinalysis. 1 month later, a telephonic questionnaire performed to evaluate lower urinary tract symptoms regardless of bacteriuria Time points measured: urine culture performed 10 days after cystoscopy, symptoms evaluated 1 month after cystoscopy Time points reported: not reported Outcomes: 2/30 participants in control group and 3/30 in treatment group had symptomatic bacteriuria Asymptomatic bacteriuria How measured: 10 days after cystoscopy, urine culture and urinalysis performed, bacteriuria considered when > 105 CFU/mL were recorded in urinalysis. 1 month later, a telephonic questionnaire performed to evaluate lower urinary tract symptoms regardless of bacteriuria Time points measured: urine culture performed 10 days after cystoscopy, symptoms evaluated 1 month after cystoscopy Time points reported: not reported Outcomes: 1/30 participants in control group and 0/30 in treatment group had asymptomatic bacteriuria
Funding sources	No information about funding
Declarations of interest	No information about conflict and interest
Notes	We tried to contact corresponding author regarding random sequence generation method, but received no response.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "Sixty patients were distributed in two groups by random assignment." Comment: method for generation of random sequence not given.
Allocation concealment (selection bias)	Low risk	Quote: "Sequence was kept hidden to the responsible conductor of assignments just before the moment of intervention." Comment: allocation concealment performed adequately.
Blinding of participants and personnel (performance bias) All outcomes	High risk	Quote: "Control did not receive any dose of antibiotics after the test, treatment was given antibiotic prophylaxis: three grams as oral single‐dose of fosfomycin trometamol, during the first two hours previous to the test." Comment: participants in control group did not receive antibiotics before cystoscopy, while participants in the treatment group receive oral single dose of fosfomycin trometamol 3 g. Unlikely that participants and personnel were blinded to intervention.
Blinding of outcome assessment (detection bias) Subjective outcomes	High risk	Quote: "Control did not receive any dose of antibiotics after the test, treatment was given antibiotic prophylaxis: three grams as oral single‐dose of fosfomycin trometamol, during the first two hours previous to the test." Comment: participants not blinded to their intervention. Risk of detection bias for symptomatic UTI and asymptomatic bacteriuria was high.
Blinding of outcome assessment (detection bias) Objective outcomes	Unclear risk	Comment: not applicable, since the objective outcome of drug resistance was not reported.
Incomplete outcome data (attrition bias) Systemic UTI	Unclear risk	Comment: outcome not reported.
Incomplete outcome data (attrition bias) Symptomatic UTI	Low risk	Quote: "No statistically significant differences were observed regarding the distribution of most baseline variables between both groups." Comment: 60/60 randomized participants (30 participants in each group) were included for analysis of this outcome, 5 participants were lost to follow‐up 1 month later for evaluation of lower urinary tract symptoms, intention‐to‐treat analysis performed for symptom analysis.
Incomplete outcome data (attrition bias) Serious adverse events	Unclear risk	Comment: outcome not reported.
Incomplete outcome data (attrition bias) Minor adverse events	Unclear risk	.Comment: outcome not reported.
Incomplete outcome data (attrition bias) Localized UTI	Unclear risk	Comment: outcome not reported.
Incomplete outcome data (attrition bias) Asymptomatic bacteriuria	Low risk	Quote: "No statistically significant differences were observed regarding the distribution of most baseline variables between both groups." Comment: 60/60 randomized participants (30 participants in each group) were included for analysis of this outcome, 5 participants were lost to follow‐up 1 month later for evaluation of lower urinary tract symptoms, intention‐to‐treat analysis performed for symptom analysis
Incomplete outcome data (attrition bias) Bacterial resistance	Unclear risk	Comment: outcome not reported.
Selective reporting (reporting bias)	Unclear risk	Comment: data reported on all outcomes specified in methods section, but there was no access to trial protocol/registration to further assess selective reporting.
Other bias	Low risk	Comment: no other bias detected.