Carter‐Brooks 2018.

Study characteristics
Methods	Study design: RCT Dates study conducted: February 2016‐March 2017
Participants	Number of participants: eligible not reported, 57 reported Setting: Connecticut Country: USA Population: women Age (mean and SD): A 64.9 ± 11.5; B 65.2 ± 10.3 Inclusion criteria: surgical management of pelvic organ prolapse requiring an overnight hospital admission Condition for hospitalisation: pelvic organ prolapse Exclusion criteria: same‐day surgery, non‐ambulatory (allowed to use an assistive device), inability to provide informed consent, age < 21 years, pregnancy or desire for future pregnancy, systematic disease known to affect bladder function (Parkinson's disease, multiple sclerosis, spina bifida, spinal cord injury or trauma and neurogenic bladder), known pre‐operative urinary retention (defined as a post‐void residual > 100 mL), an untreated UTI at the time of surgery, treatment at the time of surgery for UTI, symptoms of UTI on the day of surgery Use of antibiotic prophylaxis: not reported
Interventions	Group A (n = 27): IUC removal 4 h post‐op Group B (n = 30): IUC removal 6 am on post‐op day 1 Size and type of catheter used (e.g. Foley 16F): not reported Study definition of short‐term catheterisation (days): not reported Intended duration of catheterisation for each group: Group A: voiding trial 4 h post‐operatively Group B: voiding trial at 6 am day 1 post‐operative
Outcomes	Number of participants requiring recatheterisation* Incidence of UTI Patient comfort or discomfort VAS pain scores** Time to first void (h) Length of hospitalisation (h) Psychological outcome measures e.g. Hospital Anxiety and Depression Scale. Anxiety measured by State‐Trait Anxiety Inventory state subscale (STAI‐S)
Definition of CAUTI or bacteriuria	“Defined as a positive culture or symptoms and antibiotic treatment”
Sponsorship/funding	“This project was supported by the Clinical Research Trainee Award from Magee‐Womens Research Institute and the National Institutes of Health through grant number UL1‐TR‐000005.”
Ethical approval	“This study was approved by the Institutional Review Board of the University of Pittsburgh (PRO15100653 approved 1/14/16)”
Notes	*Derived from outcome “Spontaneous void after 1st voiding trial attempt” **Pain scores were measured using the VAS, a continuous scale comprising a horizontal line 10 cm in length, anchored by the verbal descriptors “no pain” and “worst imaginable pain”.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: “Randomization was computer generated with 1:1 group allocation to an early or standard voiding trial in fixed blocks of 6.” Comment: adequate method of randomisation
Allocation concealment (selection bias)	Low risk	Quote: “Randomization was concealed by a research assistant not involved in trial enrolment using consecutively numbered opaque envelopes” Comment: adequate method of concealment
Blinding of participants and personnel (performance bias) All outcomes	High risk	Blinding not possible
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported
Blinding of microbiological outcome (detection bias)	Low risk	Not reported. Assume urine samples were sent to a laboratory where the microbiologist would not know which patients were in the trial
Incomplete outcome data (attrition bias) All outcomes	Low risk	ITT analysis and per‐protocol analysis reported. No withdrawals
Selective reporting (reporting bias)	Low risk	Outcomes appear to be reported in full
Other bias	Low risk	Appears to be free from other sources of bias