Abstract
Background: Pelvic floor muscle training (PFMT), compared to no treatment, is effective for treating urinary incontinence (UI) in women. Feedback and biofeedback are additional resources that give women more information about their pelvic floor muscle contraction. The extra information could improve training performance by increasing capability or motivation for PFMT. The Committee on Conservative Management from the 7th International Consultation on Incontinence states that the benefit of adding biofeedback to PFMT is unclear. This review is an update of a Cochrane review last published in 2011.
Objectives: The primary objective was to assess the effects of PFMT with feedback or biofeedback, or both, for UI in women. We considered the following research questions. Are there differences in the effects of PFMT with feedback, biofeedback, or both versus PFMT without these adjuncts in the management of stress, urgency or mixed UI in women? Are there differences in the effects of feedback versus biofeedback as adjuncts to PFMT for women with UI? Are there differences in the effects of different types of biofeedback?
Search methods: We searched the Cochrane Incontinence Specialised Register (searched 27 September 2023), which includes searches of CENTRAL, MEDLINE, MEDLINE In-Process, MEDLINE Epub Ahead of Print, ClinicalTrials.gov, WHO ICTRP as well as handsearching of journals and conference proceedings, and the reference lists of relevant articles.
Selection criteria: We included only randomised controlled trials (RCTs), cluster-RCTs and quasi-RCTs in women with UI. We excluded studies that recruited women with neurological conditions, who were pregnant or less than six months postpartum. Eligible studies made one of the following comparisons: PFMT plus feedback versus PFMT alone, PFMT plus biofeedback versus PFMT alone, PFMT plus feedback or biofeedback versus PFMT alone, PFMT plus feedback versus PFMT plus biofeedback, and one type of biofeedback versus another.
Data collection and analysis: Two review authors independently assessed studies for eligibility, extracted data onto a prepiloted form, and assessed risk of bias using RoB 1. We used the GRADE approach to assess the certainty of evidence in each comparison by outcome. Our primary outcome was lower urinary tract symptom-specific quality of life. We pooled data using a standardised mean difference (SMD). Secondary outcomes were leakage episodes in 24 hours (mean difference (MD)), leakage severity (MD), subjective cure or improvement (odds ratio (OR)), satisfaction (OR), and adverse events (descriptive summary).
Main results: We included 41 completed studies with 3483 women. Most (33 studies, 3031 women) investigated the effect of PFMT with biofeedback versus PFMT alone. Eleven studies were at low risk of bias overall, 27 at unclear risk of bias, and three at high risk. Only one study reported leakage severity, with no usable data. Comparison 1. PFMT with feedback versus PFMT alone: one eligible study reported no outcome of interest. Comparison 2. PFMT with biofeedback versus PFMT alone: there was little or no difference in incontinence quality of life (SMD 0.07 lower, 95% confidence interval (CI) 0.18 lower to 0.05 higher; 11 studies, 1169 women; high-certainty evidence). Women randomised to biofeedback had 0.29 fewer leakage episodes in 24 hours versus PFMT alone (MD 0.29 lower, 95% CI 0.42 lower to 0.16 lower; 12 studies, 932 women; moderate-certainty evidence), but this slight reduction in leakage episodes may not be clinically important. Women in biofeedback arms report that there is probably little to no difference in cure or improvement (OR 1.26, 95% CI 1.00 to 1.58; 14 studies, 1383 women; moderate-certainty evidence) but may report greater satisfaction with treatment outcomes (OR 2.41, 95% CI 1.56 to 3.7; 6 studies, 390 women; low-certainty evidence). None of these outcomes were blinded. Eight studies (711 women) assessed severe adverse events but reported that there were no events. Comparison 3. PFMT with feedback or biofeedback versus PFMT alone: a single study contributed very-low certainty evidence regarding leakage episodes in 24 hours, subjective cure or improvement, and satisfaction. Comparison 4. PFMT with feedback versus PFMT with biofeedback: the evidence is very uncertain about any difference in effect between biofeedback versus feedback for incontinence-related quality of life. Not only is the evidence certainty very low, the confidence interval is very wide and there could be a more than small effect in favour of biofeedack or feedback (SMD 0.14 lower, 95% CI 0.56 lower to 0.28 higher; 2 studies, 91 women; very-low certainty evidence). There may be fewer leakage episodes in 24 hours for women receiving biofeedback verus feedback but the difference may not be clinically important and the evidence certainty is low (MD 0.28 lower, 95% CI 0.62 lower to 0.07 higher; 2 studies, 120 women; low-certainty evidence). There were no data for subjective cure, improvement or satisfaction. One study measured adverse events and none were reported. Comparison 5. PFMT with biofeedback versus PFMT with another type of biofeedback: five studies assessed this comparison, with individual studies contributing data for separate outcomes. There was low- or very-low certainty evidence about the benefits of one type of biofeedback versus another for leakage episodes in 24 hours or subjective cure or improvement, respectively. One study reported adverse events from two of nine women receiving electromyography biofeedback versus six of 10 receiving pressure biofeedback.
Authors' conclusions: PFMT with biofeedback results in little to no difference in incontinence quality of life. The addition of biofeedback to PFMT likely results in a small unimportant difference in leakage episodes in 24 hours, and likely little to no difference in patient-reported cure or improvement. Satisfaction may increase slightly for PFMT with biofeedback, based on low-certainty evidence. Five of the 33 studies in this comparison collected information about adverse events, and four reported none in either group. Adverse events reported by women using biofeedback seemed related to using a vaginal or rectal device (e.g. discomfort with device in place, vaginal discharge). The other comparisons had few, small studies, and low- to very low-certainty evidence for all outcomes. None of the studies reported any severe adverse events.