Improving Urinary Continence and Quality of Life in Prostate Cancer Patients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Improving Urinary Continence and Quality of Life in Prostate Cancer Patients (NCT01365182), a randomized na study. The primary outcome is Amount of Urinary Leakage.

2. Clinical Question

3. Trial Design

This was a randomized, parallel-group study with single masking. The registry lists the phase as NA, enrollment as 279, and the status as completed. The study start is listed as 2010-01 and primary completion as 2013-12. The sponsor was Case Western Reserve University. The condition listed is urinary incontinence, and the study title concerns improving urinary continence and quality of life in prostate cancer patients.

The registry describes two behavioral interventions and a usual-care group. In the biofeedback plus support group, participants had a 60-minute biofeedback session in pelvic floor muscle exercises and 6 biweekly peer support group sessions during 3 months. In the biofeedback plus telephone group, participants had a 60-minute biofeedback session and 6 biweekly individual telephone contacts with a therapist during 3 months. Both forms of contact were intended to help participants learn symptom self-management skills. Participants in usual care continued receiving care without intervention training sessions.

Random allocation can help make groups comparable at the start of a study, on average, when the process is implemented as intended. That general property does not establish that groups were balanced in this trial or that all randomized participants were included in an analysis. The method used to generate the allocation sequence, how assignments were concealed, and who was masked are not reported in the registry record. The record also does not specify the intended primary comparison among the groups.

The primary endpoint description says that results are reported only for participants who completed the entire study. That makes the analysis population narrower than all participants who may have entered the study, but the number of completers and the reasons others did not complete are not reported in the registry record. The record does not provide the full protocol or a statistical analysis plan, so the planned handling of outcomes across groups and time points cannot be established from this entry.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Data are reported only for those who completed the entire study.

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Amount of Urinary Leakage, measured over Measured at baseline, 3 months after baseline, and then 6 months after the baseline assessment.

The primary endpoint is the amount of urinary leakage, recorded in grams with a 1-hour pad test. It is a continuous measure: values can fall along a range rather than belonging only to categories such as present or absent. The registry specifies that the result is summarized as a mean with a standard deviation. The mean describes the average leakage in the analysed group, while the standard deviation describes how spread out individual measurements are around that average.

A timed pad test can quantify leakage during a defined assessment period. In general, objective measurement can make an endpoint easier to compare across groups than an impression alone, provided that the assessment is performed consistently. The registry record does not describe the detailed test procedures, assessor training, or whether the assessors knew group assignments.

The endpoint was assessed at baseline, 3 months after baseline, and 6 months after the baseline assessment. Repeated measurements can show how an outcome changes over time, but they also require care in interpretation: results at different assessments from the same participant are related, not independent observations. The statistical method used to account for that relationship is not reported in the registry record.

The record says that data are reported only for participants who completed the entire study. It does not give the mean or standard deviation at any assessment, nor a numerical comparison between groups. Thus, the endpoint is described, but its observed values and the precision of any estimated effect cannot be assessed from the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry labels the primary outcome as a continuous measure summarized by a mean and standard deviation. In general, a mean gives a group’s average value, while a standard deviation describes the variability of individual observations around that average. Both are useful for understanding a distribution, but neither alone gives a complete comparison between groups. A treatment contrast would require the relevant group estimates and an analysis that accounts for the design and outcome schedule. The registry record does not report those estimates or an analysis.

What a confidence interval would add

In general, a confidence interval gives a range of values compatible with an estimated effect under a statistical model and its assumptions. It communicates precision as well as direction and size: a narrow interval indicates greater precision than a wide interval. A p-value, in contrast, summarizes how unusual the observed data would be under a specified null model; it does not measure the size or importance of an effect. Neither a confidence interval nor a p-value for the primary endpoint is reported in the registry record. No conclusion about the strength or precision of evidence for urinary leakage can therefore be drawn from this entry.

Repeated assessments

The endpoint was measured at baseline, 3 months after baseline, and 6 months after the baseline assessment. In general, repeated measurements from the same participant tend to be related. An analysis that treats all measurements as independent can misrepresent uncertainty because it ignores that within-participant relationship. A repeated-measures model or another appropriate approach may account for it, but the registry does not identify which method was used. It also does not report whether the main analysis compared groups at a particular assessment, compared changes from baseline, or modelled the pattern across assessments.

Baseline measurements can describe the starting values and may be used in an outcome analysis, but the registry record does not say how baseline values were handled. In general, adjusting for baseline can improve precision when the adjustment is appropriately specified. That general principle does not establish that baseline adjustment was planned or performed in this study. The record gives no model specification, covariates, or details about assumptions for the outcome analysis.

Randomization and masking

The study is listed as randomized and parallel. In general, random allocation aims to balance measured and unmeasured characteristics across study groups on average. It does not guarantee balance in a particular study, and it does not prevent bias from incomplete follow-up, measurement issues, or analysis choices. The registry does not report the allocation-generation procedure or concealment process. It lists single masking but does not identify who was masked. Those details matter when considering how treatment knowledge might influence care, outcome assessment, or reporting; they cannot be inferred from the masking label alone.

The record describes a completer-only population for the primary endpoint. General statistical practice distinguishes an analysis of participants as randomized from analyses limited to people who received or completed assigned procedures. These populations answer different questions and can be affected differently by missing follow-up. The registry does not identify an intention-to-treat, per-protocol, or other named analysis population. Nor does it report an approach such as imputation, a likelihood-based method, or sensitivity analysis for missing observations.

Over-dispersion and outcome distributions

As a general concept, over-dispersion means that observed variability is greater than a statistical model expects. It is most often discussed for count outcomes, but the broader lesson is that the assumed distribution and variability should fit the data. Here the primary measure is continuous and is summarized by a mean and standard deviation. The registry record does not describe the distribution of pad-test values, report diagnostic checks, or say whether transformations or robust methods were considered. It would be inappropriate to assume a particular distribution or modelling strategy from the outcome label alone.

Planning illustrations

The sample-size section is described as a planning illustration computed from the observed effect, not as the trial’s own design calculation. Its assumptions specify a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation; the effect to detect is a stated fraction of the observed effect. The record also distinguishes participants per arm for ordinary outcomes from total events for time-to-event outcomes. The primary endpoint is continuous, not time-to-event. No numerical sample-size illustration values appear in the registry record.

In general, a planning calculation estimates the sample size needed under chosen assumptions about the effect, variability, significance level, and desired power. Changing the assumed effect changes the resulting planning requirement. Such figures are not observed power, do not describe the probability that this completed study detected an effect, and do not replace an analysis of the posted outcomes. The registry record does not report the study’s original sample-size justification or its planned power. The illustration should therefore be understood as a conditional planning aid, not a reconstruction of the trial’s design rationale.

Finally, there is no reported primary-outcome analysis to compare with the assumptions of a statistical method. The registry gives neither an estimate nor its uncertainty, and it does not describe model checks or sensitivity analyses. General explanations of these methods clarify what information would be useful, but they cannot fill in analysis details that are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The primary endpoint was assessed at baseline, 3 months after baseline, and 6 months after the baseline assessment. Multiple assessments can create more than one possible statistical comparison. In general, if many outcomes, time points, or group contrasts are tested, the chance of at least one apparently notable result can increase unless the analysis plan accounts for that multiplicity. The registry record does not report a multiplicity adjustment, a hierarchy of comparisons, or a prespecified primary time point. It also does not identify which group contrast was the primary comparison.

The registry lists 2 outcome measures and 0 analyses. It describes the primary outcome, but the other outcome measure and any analysis results are not detailed in this record. Whether multiple outcomes were part of the planned inferential analysis, and how any multiplicity was to be handled, are not reported in the registry record. Consequently, it is not possible to assess whether the posted analysis controlled the interpretation of multiple tests.

For the primary outcome, the registry says that data are reported only for participants who completed the entire study. It does not provide the number of participants with observed measurements at each assessment, the number who did not complete, or reasons for missing measurements. The method used to handle missing data is not reported. In general, restricting an analysis to completers can be problematic if completion is related to outcome values or group assignment; that is a possible source of bias, not a demonstrated feature of this study.

The record does not state whether analyses followed randomized assignment, whether another analysis population was used, or whether sensitivity analyses examined the effect of missing data. These omissions prevent a full assessment of how representative the reported endpoint data are of all randomized participants. Since numerical primary-outcome analyses are absent, neither multiplicity nor missing-data handling can be evaluated against actual estimates.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Serious events with the highest arm-level rate: urinary tract infection (1.2%), fall (1.2%).

The registry reports serious adverse event figures separately for each group. For BF+Support, 81 participants were listed as at risk and 0 as affected by a serious event. For BF+PHONE, 81 were listed as at risk and 2 as affected. For usual care, 82 were listed as at risk and 1 as affected. Deaths were reported as 0 in each group. The registry lists 0 affected by other adverse events in each group.

The top serious-event terms listed are urinary tract infection at 1.2% and fall at 1.2%. The record does not provide an arm-specific breakdown for those terms, so the percentages should not be assigned to a particular group on the basis of this entry. It also does not describe event severity beyond the serious-event classification, timing, duration, relatedness to the intervention, or the criteria used to judge whether an event was caused by study participation.

These figures are descriptive counts, not evidence by themselves that an intervention caused or prevented an event. A comparison of safety would require interpretation of the event definitions, exposure and follow-up, and the completeness of reporting. The posted safety information should not be taken as a complete account of all possible harms, and it does not substitute for the missing primary urinary leakage analysis.

12. What the Result Does, and Does Not, Mean

This registry entry establishes the broad question the study addressed: urinary leakage in patients with prostate cancer and persistent urinary incontinence, in a study of biofeedback paired with peer support or therapist telephone contact and compared with usual care. It specifies a measurable primary endpoint, a 1-hour pad test recorded in grams, and assessments at baseline, 3 months after baseline, and 6 months after the baseline assessment. These details help readers understand what the study set out to measure.

The record does not establish what the outcome values were. It contains no reported means, standard deviations, group contrasts, confidence intervals, or p-values for the primary endpoint. As a result, it cannot show the direction or magnitude of an observed difference, the precision of an estimate, or whether any analysis supported a group difference. It also does not identify the primary contrast among the described groups. Statements that one approach improved continence, had no effect, or was better than another would go beyond the posted primary-outcome information.

Likewise, the record does not show whether outcome patterns changed over time or whether any observed difference was sustained at the later assessment. The assessment schedule alone is not evidence of a particular trajectory. Because primary-outcome data are described as coming only from participants who completed the entire study, the record also does not establish how results might differ for all randomized participants. The missing completion and missing-data details limit interpretation of any completer-only results, even if numerical values were displayed elsewhere.

The adverse-event figures describe reported serious events and deaths by group, but they do not establish causation or provide a complete safety comparison. They are separate from the primary endpoint and should not be used to infer changes in urinary leakage or quality of life. In general, a registry record is useful for documenting study design and posted results, but an incomplete results entry cannot answer questions that require the missing outcome analysis.

The appropriate reading is therefore narrow: the study design and endpoint are identifiable, while the primary result and its statistical uncertainty are not reported in the registry record. The tables, plots, and planning section can organize available information, but they cannot turn absent primary-outcome analyses into evidence for or against a difference.

13. Why This Trial Matters Statistically

Statistically, this study raises a useful distinction between specifying an outcome and reporting an analysable result. The registry names a continuous urinary leakage measure, gives its unit and measurement procedure, and sets out assessments over time. Those details make the intended endpoint understandable. But without group summaries and a statistical comparison, readers cannot evaluate the size or precision of an effect. A well-described endpoint is necessary for interpretation, but it is not a substitute for results.

The intervention structure also makes the comparison question important. The record describes biofeedback paired with two different forms of added support, alongside usual care. Different comparisons would address different questions: the support formats could be compared with each other, or each intervention could be compared with usual care. The registry record does not identify the primary contrast or provide the analyses, so these questions cannot be distinguished statistically from the posted information.

The repeated assessment schedule highlights the need to consider both time and within-participant dependence. A group comparison at a single follow-up, a comparison of change from baseline, and a model of outcomes across assessments do not necessarily estimate the same quantity. General statistical principles can explain why the distinction matters, but the analysis chosen is not reported. Similarly, the completer-only description makes the analysis population central to interpretation. Readers need to know how many participants contributed data and what happened to missing measurements to judge how well the results represent the randomized study groups.

Finally, the sample-size illustration is distinct from the original design rationale and from an analysis of observed results. Treating planning calculations as evidence about what the completed study found would confuse design assumptions with outcome evidence. The registry entry is therefore statistically informative about the questions that require attention—comparison choice, repeated measurements, missing data, and precision—even though it does not report the primary analysis needed to resolve them.

14. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

A central limitation of this registry entry is that it does not report numerical results for the primary endpoint. It describes the amount of urinary leakage and the schedule of assessments, but does not give group means, standard deviations, effect estimates, or measures of uncertainty. The record lists 0 analyses, so the primary outcome cannot be statistically evaluated from this entry.

The endpoint data are described as being reported only for participants who completed the entire study. The number of completers, follow-up completeness at each assessment, and reasons for non-completion are not reported in the registry record. The method for handling missing measurements and the analysis population are also not reported. These gaps make it impossible to assess how the completer-only reporting relates to all randomized participants.

The record describes several groups and repeated assessments but does not state the prespecified primary comparison or the primary time point. It does not identify the statistical model, baseline adjustment, assumptions, or multiplicity approach. The degree to which analyses followed a prespecified plan cannot be assessed because the full statistical plan is not reported in the registry record.

Although the study is listed as single-masked, the identity of the masked parties is not specified. The allocation-generation and concealment methods are not reported. The record also does not provide details of usual care, the pad-test procedures beyond its duration and unit, or whether outcome assessors were masked. These are limitations of what can be evaluated from the registry entry, not evidence that any particular procedure was inadequate.

Safety information is limited to the posted serious and other adverse-event counts, deaths, and top serious-event terms. Event timing, relatedness, definitions, and group-specific details for the named terms are not reported. The registry also does not provide numerical findings for the other outcome measure. These omissions leave important questions about outcomes and study conduct unanswered in this record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Improving Urinary Continence and Quality of Life in Prostate Cancer Patients — NCT01365182.
• Registry record last updated 2022-10-12; status last verified 2022-09.
• Results first posted 2022-10-12.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

The registry describes a completed randomized, parallel-group study with single masking and enrollment of 279. It concerns urinary incontinence in prostate cancer patients and evaluates biofeedback pelvic floor muscle exercise paired with peer support or therapist telephone contact, compared with usual care. The listed sponsor is Case Western Reserve University.

The primary endpoint is urinary leakage in grams on a 1-hour pad test, assessed at baseline, 3 months after baseline, and 6 months after the baseline assessment. The registry says that endpoint data are reported only for participants who completed the entire study, but numerical results and analyses are not reported in the registry record. The record lists 2 outcome measures and 0 analyses.

Serious adverse-event counts and deaths are listed by group, with urinary tract infection and fall named among the top serious-event terms. The entry does not provide the primary-outcome estimates needed to assess differences or their precision. Its design and measurement details are identifiable, but its primary statistical result is not.