Piergiovanni 1991.

Methods	RCT or quasi‐RCT: RCT Setting: Switzerland
Participants	Population: patients requiring bladder drainage while hospitalised Inclusion criteria: patients with sterile urine needing a bladder drainage for non‐urological indications (54% perioperative, 29 % urinary retention, 11% prostatic hypertrophy, 6% incontinence and nursing) Age (mean): A: 63 years; B: 64 years Number of participants: Eligible: 100 Randomised: 100 Reported: 75 Dropouts (n of participants + reasons) 25 patients were excluded: 10 patients had bacteriuria at admission, 8 died, 5 already had a catheter and 2 were transferred to another hospital
Interventions	A (n = 41): Indwelling urethral catheterisation (Charriere 12 to 20; Foley) B (n = 34): Suprapubic catheterisation (Charriere 10; Cystofix) Duration of intervention: At least 5 days
Outcomes	Primary outcome (symptomatic UTI): not reported Bacteriuria: A: 12/41; B: 4/34 Definition of bacteriuria: Significant bacteriuria was defined 104 cfu/ml. The urine was monitored at catheter insertion and 3 days after removal of the catheter Discomfort: A: 38/41; B: 18/34 Participants with pain: A: 18/41; B: 1/34
Sponsorship/Funding	Not reported
Notes	No definition was given for the outcome measure 'discomfort' No definition was given for the outcome measure 'pain' Some participants received antibiotics (65% in each study arm)
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	“randomization into two groups” “les deux groups ont été tires au sort avant le début de l’étude, de manière aléatoire” [the two groups were chosen by lot before the start of the study, randomly] – not enough information about method of randomisation
Allocation concealment (selection bias)	Unclear risk	No information provided
Blinding of participants	High risk	No information given but as transurethral and suprapubic can assume that participants were not blinded
Blinding of personnel	High risk	“Elles ont été mises en place soit par le personnel infirmier, soit par les chirurgiens ou les anesthésistes” [they (catheters) were put in place by nurse, surgeon or anaesthetists] – no mention of blinding of personnel, can assume those involved in insertion were not blinded
Blinding of microbiological outcome assessment	Low risk	Bacteriuria assessed by microbiologists, who would not know allocation of participant to suprapubic or transurethral catheter
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	No information given
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	“25 malades ont été retires de l’étude selon les critères suivants: infection des urines au moment du sondage 10; décès 8; sonde à demeure 5; transferts dans d’autres hôpitaux 2.” [25 patients were withdrawn from the study according to the following criteria: UTI at time of catheter insertion 10; 8 deaths ; catheter remained indwelling 5; transfers to other hospitals 2] unclear which intervention group in, could be significant
Selective reporting (reporting bias)	Unclear risk	Unable to access protocol, so some uncertainty about selective reporting
Other bias	Low risk	Appears to be free of other sources of bias