***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: Eleven trials were selected for inclusion in the review, including a total of 776 men. They were generally small; all were of poor quality and all were deemed to have high risk of bias. Performing intermittent self-dilatationversus not performing intermittent self-dilatation The data from six trials were heterogeneous, imprecise and had a high risk of bias, but indicated that recurrent urethral stricture was less likely in men who performed intermittent self-dilatation than men who did not perform intermittent self-dilatation (RR 0.70, 95% CI 0.48 to 1.00; very low quality evidence). Adverse events were generally poorly reported: two trials did not report adverse events and two trials reported adverse events only for the intervention group. Meta-analysis of the remaining two trials found no evidence of a difference between performing intermittent self-dilatation and not performing it (RR 0.60, 95% CI 0.11 to 3.26). No trials formally assessed acceptability, and no trials reported on patient-reported lower urinary tract symptoms, patient-reported health-related quality of life, or cost-effectiveness. One programme of intermittent self-dilatationversus another We identified two trials that compared different durations of intermittent self-dilatation, but data were not combined. One study could not draw robust conclusions owing to cross-over, protocol deviation, administrative error, post-hoc analysis and incomplete outcome reporting. The other study found no evidence of a difference between intermittent self-dilatation for six months versus for 12 months after optical urethrotomy (RR 0.67, 95% CI 0.12 to 3.64), although again the evidence is limited by the small sample size and risk of bias in the included study. Adverse events were reported narratively and were not stratified by group. No trials formally assessed acceptability, and no trials reported on patient-reported lower urinary tract symptoms, patient-reported health-related quality of life, or cost-effectiveness. One device for performing intermittent self-dilatationversus another Three trials compared one device for performing intermittent self-dilatation with another. Results from one trial at a high risk of bias were too uncertain to determine the effects of a low friction hydrophilic catheter and a standard polyvinyl chloride catheter on the risk of recurrent urethral stricture (RR 0.32, 95% CI 0.07 to 1.40). Similarly one study did not find evidence of a difference between one percent triamcinolone gel for lubricating the intermittent self-dilatation catheter versus water-based gel on risk of recurrent urethral stricture (RR 0.68, 95% CI 0.35 to 1.32). Two trials reported adverse events, but one did not provide sufficient detail for analysis. The other small study reported fewer instances of prostatitis, urethral bleeding or bacteriuria with a low friction hydrophilic catheter compared with a standard polyvinyl chloride catheter (RR 0.13, 95% CI 0.02 to 0.98). ‘Happiness with the intervention’ was assessed using a non-validated scale in one study, but no trials formally assessed patient-reported health-related quality of life or acceptability. No trials reported on patient-reported lower urinary tract symptoms or cost-effectiveness. GRADE quality assessment The evidence that intermittent self-dilatation reduces the risk of recurrent urethral stricture after surgical intervention was downgraded to 'very low' on the basis that the studies comprising the meta-analysis were deemed to have high risk of bias, and the data was imprecise and inconsistent. Insufficient evidence No trials provided cost-effectiveness data or used a validated patient-reported outcome measure, and adverse events were not reported rigorously. Acceptability of the intervention to patients has not been assessed quantitatively or qualitatively. Performing intermittent self-dilatation may confer a reduced risk of recurrent urethral stricture after endoscopic treatment. We have very little confidence in the estimate of the effect owing to the very low quality of the evidence. Evidence for other comparisons and outcomes is limited. Further research is required to determine whether the apparent benefit is sufficient to make the intervention worthwhile, and in whom.
Output:

We found 11 trials involving a total of 776 men across eight countries for this review. A combination of results from six trials involving a total of 404 participants indicated that men with urethral stricture who perform intermittent self-dilatation may have less chance of their urethral stricture coming back than men with a urethral stricture who do not perform intermittent self-dilatation. We can not be confident about this finding, however, because the quality of the evidence was very low. There were no trials that looked at whether intermittent self-dilatation is a cost-effective health care intervention and there were no trials that used reliable health questionnaires to find out whether intermittent self-dilatation reduces men's urinary symptoms or improves their overall well being. On the whole the trials did not report side effects in a way that was useful for estimating the risks of performing intermittent self-dilatation. We do not know yet whether certain types of catheter are better than others for performing intermittent self-dilatation. It is also unclear how often or for how long men should perform intermittent self-dilatation to give themselves the best chance of staying free from urethral strictures. The trials in this review were generally small and poorly designed or poorly explained. All of the trials were conducted in a way which meant they had a high chance of generating an answer that does not represent the truth.