Cardenas 2011

Methods	DESIGN: Randomised controlled trial BLINDING PROCEDURES: Non‐blinded SAMPLE CALCULATION: Yes DURATION: Up to 6 months WITHDRAWALS/DROPOUTS: 110 ITT: Not stated GEOGRAPHICAL LOCATION: North America SETTING: Hospital and community
Participants	N = 224 DIAGNOSIS: Spinal cord injury no longer than 3 months ELIGIBLE: Not stated ENROLLED: 224 COMPLETED: 114 AGE: Adults GENDER: 161 male, 39 female (enrolled ‐ did not state gender of numbers completing)
Interventions	Hydrophilic‐coated catheter, activated versus uncoated catheter, non‐lubricated (single use both arms)
Outcomes	Time to 1st UTI; UTI incidence; microhaematuria measured at weeks 3 and 4; satisfaction measured at 45 days
Notes	Time to first antibiotic treated symptomatic UTI was significantly delayed in hydrophilic‐coated catheter group. 14 reports of bleeding in hydrophilic and 6 reports in uncoated.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	"A centralized computer‐generated randomization list was generated"
Allocation concealment (selection bias)	Low risk	"Sealed envelopes were provided"
Blinding of participants and personnel (performance bias) All outcomes	Low risk	"The inability to blind participants and clinicians to the catheter type is a potential limitation of the trial". Probably did not create performance bias.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	"The inability to blind participants and clinicians to the catheter type is a potential limitation of the trial". Outcome of UTI was participant‐ and clinician‐determined.
Incomplete outcome data (attrition bias) All outcomes	High risk	"In the hydrophilic catheter group... many of the investigational sites did not routinely use hydrophilic catheters. The trial protocol did not include a number of training catheterizations". A greater number of participants dropped out in the hydrophilic‐coated group, resulting in incomplete outcome data both for UTI, and participant satisfaction, which did not appear to have been measured in these participants.
Source of Funding	Unclear risk	Coloplast A/S