Key messages
• In women with urinary incontinence (involuntary loss of urine), using a biofeedback device (a device with a sensor that measures muscle contractions and gives audio or visual feedback) with pelvic floor muscle training makes little or no difference to incontinence-related quality of life, how often leakage happens, or how often women feel their symptoms are cured or improved. Most evidence comes from women with stress urinary incontinence (leakage caused by coughing, sneezing, walking, running or jumping).
• Few studies measured unwanted effects; those that did found they were minor and short-lived, or said there were none.
• It is unclear if one type of biofeedback is better than any other, or if biofeedback is better than feedback.
What is urinary incontinence?
Urinary incontinence is the involuntary loss of urine. It is a common condition for women and may be caused by ageing, pregnancy, childbirth, being overweight, or drinking too much alcohol or caffeine. The main types are stress urinary incontinence - leakage caused by a physical effort - such as coughing, sneezing, walking, running or jumping; and urgency urinary incontinence - leakage while experiencing an overwhelming need to urinate. Some women have both types, called mixed urinary incontinence.
What are pelvic floor muscle training, feedback and biofeedback?
Often, the first treatment for urinary incontinence is 'pelvic floor muscle training', also called pelvic floor exercises or Kegel exercises. The pelvic floor muscles sit at the base of the pelvis, and support the bowel and bladder. In women, they also support the uterus and vagina. Strengthening these muscles may help to give women more control over their bladder. Training involves contracting (squeezing and lifting) these muscles. It is difficult for many women to tell if they are exercising them effectively. Feedback and biofeedback can give women more information about how well they are doing. 'Feedback' may be a health professional touching or squeezing the muscles, then telling the woman what they feel. 'Biofeedback' uses a device with a sensor. These devices are put in the vagina or rectum (back passage), and measure the change in the muscle as it contracts, sending a signal to a screen or speaker, so women can see or hear it.
What did we want to find out?
We wanted to know if adding feedback or biofeedback, or both, to pelvic floor muscle training:
• improves women's quality of life related to incontinence;
• reduces the number of times women experience leakage of urine;
• reduces the amount of the leakage and how often it happens.
We also wanted to know if women felt their incontinence was cured or improved, whether they were satisfied with the treatment, and whether there were any unwanted effects with feedback or biofeedback.
What did we do?
We searched for studies that added feedback, biofeedback, or both to pelvic floor muscle training in women with urinary incontinence and compared this to pelvic floor muscle training without them. We also searched for studies that compared one type of biofeedback against another. We compared and summarised their results and rated our confidence in the evidence, based on factors such as study methods and sizes.
What did we find?
We found 41 studies with 3483 women with urinary incontinence. Most women had stress urinary incontinence, and were aged between 18 and 80 years with an average age of about 55 years. Most studies lasted three months and were done in high-income countries. A few studies had a commercial funder like a biofeedback device company.
Thirty-three studies added biofeedback to pelvic floor muscle training and compared that to muscle training alone. We found little or no difference in quality of life and a slight reduction in how often leakage happens in the women receiving biofeedback, but this is unlikely to be a noticeable difference. Women who receive biofeedback are probably unlikely to say their condition is cured or improved, but may feel greater satisfaction with their treatment or the outcome of their treatment.
It is unclear if there is a difference between women who received feedback or biofeedback versus none, women who received feedback versus biofeedback, or who received one type of biofeedback versus another type of biofeedback.
Many studies did not report unwanted effects of treatment. Those that did said there were none or not many, and none were serious or long-lasting.
What are the limitations of the evidence?
We are confident that there is little to no difference between pelvic floor muscle training with biofeedback versus training alone to treat urinary incontinence in women.
We are not confident in any other evidence because the studies were few and small, and they did not measure the outcomes we were interested in.
How up to date is this evidence?
The evidence is up to date to 27 September 2023. This review updates a previous Cochrane Review published in 2011.
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.
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.
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?
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.
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.
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).
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.