Detrol Long Acting (LA) vs Estrace Vaginal Cream for the Treatment of Overactive Bladder Symptoms: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Detrol Long Acting (LA) vs Estrace Vaginal Cream for the Treatment of Overactive Bladder Symptoms (NCT00465894), a randomized na study. The primary outcome is Evaluate Subjective Patient Change in Irritative Urinary Symptoms as Measured by the Overactive Bladder Questionnaire (OAB-q) Symptom Bother Score.

2. Clinical Question

The study description frames the comparison as whether long-acting tolterodine or low-dose intravaginal estrogen confers greater benefit for overactive bladder symptoms. The stated hypothesis favors low-dose intravaginal estrogen, but a hypothesis is not a finding. The registry record does not report the primary outcome values or a between-group estimate, so the direction and size of any difference cannot be assessed from the posted results.

The study also describes an interest in whether adding the other therapy to the treatment regimen could confer benefit at 24 weeks and 52 weeks. Those are secondary questions, distinct from the primary comparison at 12 weeks. The registry record lists multiple secondary outcome measures, including patient-reported symptoms, quality of life, a voiding diary, impressions of improvement and satisfaction. Their comparative numerical findings are not reported in the registry record.

3. Trial Design

This was a randomized, parallel-group trial with no masking. The registry record lists enrollment of 58 participants: 30 in Group 1, assigned to extended-release tolterodine LA, and 28 in Group 2, assigned to intravaginal estradiol cream. Because the trial was unmasked, participants and study personnel were not blinded to treatment assignment according to the registry’s masking description. The record does not report further details about the randomization procedure or allocation concealment.

The condition listed was overactive bladder. The official title identifies the intended population as post-menopausal women. The registry describes a drug intervention in each group and gives brief descriptions of their intended use. Details such as dosing, treatment adherence, eligibility criteria, or concomitant care are not reported in the registry record.

The primary outcome was the Overactive Bladder Questionnaire symptom-bother score, assessed from baseline through 12 weeks of intervention. The registry describes the score as ranging from 0 to 100, with higher scores indicating greater symptom bother. The primary outcome was designated as a mean continuous measure with standard deviation as its dispersion measure. The registry does not report numerical group means, standard deviations, or a comparative treatment estimate.

The study was sponsored by the University of Alabama at Birmingham. Its status is listed as completed, with a start date of 2007-04 and primary completion in 2010-07. The phase is listed as NA. The registry describes secondary questions involving 24-week and 52-week follow-up and lists 13 outcome measures, but detailed results for those measures are not reported in the registry record. The record also does not specify a statistical analysis plan, a target sample-size justification, or additional design features beyond randomization, no masking, and a parallel model.

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.

Treatment For 12 Weeks

Reasons for not completing this period:

Treatment From 12 Weeks To 24 Weeks

Treatment From 24 Weeks to 52 Weeks

Analysis population for the primary outcome, as defined in the registry: A baseline measure was achieved for Group 1 with 30 patients and Group 2 with 28 patients. At the 12 week measurement period, we were unable to analyze 5 patients in Group 1 (leaving 25 patients) and unable to analyze 3 patients in Group 2 (leaving 25 patients). These participants left for reasons identified in the Participant Flow.

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 Evaluate Subjective Patient Change in Irritative Urinary Symptoms as Measured by the Overactive Bladder Questionnaire (OAB-q) Symptom Bother Score, measured over From baseline through 12 Weeks of Intervention.

The primary endpoint was subjective symptom bother measured by the Overactive Bladder Questionnaire, or OAB-q, symptom-bother score. The registry describes the symptom-bother component as eight questions, combined into a score from 0 to 100. Higher scores indicate greater symptom bother. This direction is important when interpreting a score: a larger value represents more reported bother, not less.

A questionnaire-based measure captures the participant’s report of how troublesome symptoms are. That is relevant to a trial focused on irritative urinary symptoms, because a clinical assessment may include the experienced impact of symptoms as well as their occurrence. The OAB-q score provides a defined scale for representing that reported experience. In general, repeated measurements can describe change over time, while a comparison between randomized groups can estimate how their reported outcomes differ under the study conditions.

The registry specifies a timeframe from baseline through 12 weeks of intervention and identifies the outcome as a mean with standard deviation. It does not report the actual baseline or follow-up means, the amount of change, or a between-group estimate and its uncertainty. Nor does the record excerpt specify exactly how the repeated measurements were incorporated into the analysis. As a result, the endpoint’s measurement and intended timing are clear, but its comparative result cannot be interpreted from the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical methods are useful only when the outcome definition, the comparison, and the handling of the data are clear. The registry record identifies a randomized parallel-group comparison and a continuous primary outcome, but does not report the detailed analysis method or the numerical primary results. The following concepts explain how such a result would generally be read; they do not describe an analysis confirmed for this trial.

What does a mean and standard deviation describe?

General explanation: for a continuous outcome, a group mean represents the average observed score among the participants included in that calculation. The standard deviation describes how spread out individual scores are around that group mean. It is not the uncertainty of the mean itself, and it does not show the range of all observed values. The registry identifies the OAB-q symptom-bother outcome as a mean with standard deviation, but does not report those numerical summaries.

Because higher OAB-q symptom-bother scores indicate greater bother, a group’s score needs to be interpreted in that direction. If outcomes are measured at baseline and follow-up, investigators may analyze follow-up scores, changes from baseline, or both within a model. These approaches answer related but not identical questions and can depend on the analysis plan. The registry record does not report which approach was used, whether baseline scores were included as an adjustment, or how repeated observations were modeled.

What does a treatment estimate and confidence interval communicate?

General explanation: a treatment estimate expresses the contrast between groups on the outcome scale, according to the chosen analysis. A confidence interval conveys the statistical uncertainty around that estimate under the assumptions of the method. A narrower interval indicates greater precision; a wider interval indicates less precision. The interval’s location and width matter alongside the point estimate. A p-value alone would not show the size of a difference or its precision.

The registry record does not report a treatment estimate, confidence interval, or p-value for the primary outcome. Consequently, there is no basis to characterize the observed difference as favoring one group, to assess its precision, or to judge how compatible the results are with a range of possible effects. No unadjusted recalculation can be made from the available information because the primary outcome summaries are absent.

What does randomization contribute?

General explanation: random assignment is intended to make treatment groups comparable, on average, with respect to factors known and unknown at enrollment. It supports interpretation of a between-group comparison, provided that the analysis and follow-up preserve the benefits of assignment. Randomization does not guarantee that every characteristic is balanced in a particular trial, and it does not remove uncertainty from a modest sample. The registry says the trial was randomized, but does not report the sequence-generation method, allocation concealment, baseline outcome values, or a detailed account of the analysis population.

No masking was reported. General explanation: when participants and study personnel know treatment assignment, expectations or care experiences can influence outcomes, especially when an endpoint depends on self-report. This possibility is relevant to a subjective questionnaire outcome, but the registry does not quantify any such influence. It is a design consideration, not evidence that reported scores were biased.

How should missing measurements be considered?

General explanation: a missing follow-up measure reduces the observed information and can affect a comparison if the participants with missing data differ in relevant ways from those with observed data. The consequences depend on why values are missing and how the analysis handles them. Common approaches make different assumptions, so knowing the method matters. The registry reports that some participants could not be analyzed at the 12-week measurement, but its reason text is truncated and the missing-data method is not reported in the registry record.

The available counts show the number with baseline measures and the number left for analysis at 12 weeks in each group. They do not show whether missingness was related to symptom scores, treatment assignment, or another factor. They also do not identify whether the analysis used only observed cases or another method. No assumption about the missing outcomes should be treated as a reported finding.

What can be said about planning and power?

General explanation: a sample-size calculation is a planning exercise that depends on assumptions about the effect to detect, outcome variability, significance level, allocation, and analysis. It is not a measure of whether a completed trial had adequate power after results are observed. The registry record does not report the trial’s own sample-size justification, target effect, or planned power. Any planning illustrations associated with an observed effect are not the trial’s original design justification and do not establish observed power.

The record states that one analysis is listed, but does not identify enough detail to characterize its model, covariates, handling of repeated measures, or inferential procedure. These omissions limit reproducibility and make it inappropriate to attribute a particular statistical method to the investigators. The numerical endpoint results are also absent, so the main statistical question remains unresolved in the registry information.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 13 outcome measures, including several secondary assessments of subjective symptom change, health-related quality of life, voiding diary results, global impression of improvement, and satisfaction. Testing many outcomes or time points can increase the chance of finding an apparently notable result by chance if each is interpreted separately. General explanation: a prespecified testing hierarchy or multiplicity adjustment can help control that issue, but the appropriate approach depends on the trial’s aims and analysis plan.

The registry record does not report whether a multiplicity strategy was specified, which secondary outcomes were prioritized, or how the multiple outcomes and follow-up times were analyzed. It also does not provide numerical secondary results in the information. Thus, no claim about statistical significance across outcomes, or adjustment for multiple comparisons, can be made.

For the primary outcome, the record reports baseline measures for 30 participants in Group 1 and 28 in Group 2. At 12 weeks, 25 participants in each group remained analyzable; the registry notes that 5 in Group 1 and 3 in Group 2 could not be analyzed. The stated reason text is incomplete. The method used to handle missing measurements, the analysis population definition, and whether participants were analyzed according to randomized assignment are not reported in the registry record.

General explanation: missing-data assumptions can affect estimated group differences, especially when the probability of having an observed outcome depends on participant characteristics or outcomes. A complete-case analysis, an imputation approach, and a model using repeated observations may rely on different assumptions. The registry does not establish which approach was used, so the available counts alone cannot show whether missingness changed the result. Nor can they establish the direction of any possible bias.

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 1% reporting threshold.

Most frequent non-serious adverse event terms

The registry reports zero serious adverse events among the 30 participants at risk in Group 1, extended-release tolterodine, and zero among the 28 participants at risk in Group 2, intravaginal estradiol cream. It also records other adverse events for 17 of 30 participants in Group 1 and 6 of 28 participants in Group 2. No deaths are reported in either group.

Serious and other adverse events are presented as separate categories in the registry. Zero serious events means that none were recorded in the listed group counts; it does not mean that no adverse events of any kind occurred. The other-event counts indicate participants affected, rather than a total count of individual event episodes. The registry information does not define the “other” category, describe the events, give severity or timing, or report an inferential comparison between groups.

These figures are descriptive and should not be read as proof that treatment caused or prevented an event. They also do not provide a complete assessment of comparative safety, particularly without event-level details and a stated safety analysis method. The numbers should be interpreted in the context of the recorded participants at risk and the limited reporting available in the registry record.

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

The registry record documents a randomized comparison of extended-release tolterodine LA with intravaginal estradiol cream for overactive bladder symptoms in post-menopausal women. It specifies a primary patient-reported symptom-bother outcome and a 12-week timeframe. Those details establish what the trial set out to compare, but the primary outcome values and comparative estimate are not reported in the registry information.

Without the outcome summaries and uncertainty estimates, the posted information cannot show whether symptom bother changed differently between the groups, how large any difference was, or how precise an estimate might be. The stated hypothesis favoring intravaginal estrogen is not a result. Likewise, a trial’s completion status and its enrollment count do not by themselves answer its efficacy question.

The registry provides limited follow-up availability counts and descriptive adverse-event counts. Those can be reported as recorded, but they do not replace the missing efficacy analysis or establish a causal safety contrast. The secondary outcome list and the study description’s questions about later follow-up indicate broader interests, but numerical results for those outcomes are not reported in the registry record.

General explanation: a finding from a randomized trial is most informative when the outcome estimate, precision, analysis population, missing-data handling, and methods are available. Without these details, readers cannot evaluate the strength of evidence, the plausibility of alternative estimates, or the extent to which the analysis reflects randomized assignment. No treatment conclusion should be inferred from the incomplete result information.

The appropriate statistical reading is therefore bounded: the design and outcome question are identifiable, but the central comparative outcome cannot be evaluated from the posted results. The absence of a reported estimate is not evidence of no difference, and it is not evidence that either intervention is superior.

13. Why This Trial Matters Statistically

This trial raises a useful statistical question about how patient-reported symptom bother can be compared between randomized groups. The OAB-q symptom-bother score has a defined direction, with higher scores indicating greater bother, and a stated follow-up period from baseline through 12 weeks. Together, these features make the endpoint interpretable in principle: a complete analysis could describe the group outcomes and estimate their contrast.

The trial also illustrates why a clearly defined research question is only part of a statistical record. The registry identifies randomization and parallel groups, but the primary numerical results and analysis details are not reported in the information. Without the estimated contrast and its uncertainty, readers cannot determine the magnitude or precision of the result. Without the analysis description, they cannot assess how baseline measures, repeated observations, or missing follow-up were handled.

Participant-reported outcomes are particularly relevant to questions about symptom experience, while also requiring attention to measurement and study conduct. The trial was unmasked, and the primary measure was subjective. General explanation: lack of masking can be a consideration when responses may be affected by expectations, but it does not demonstrate that this occurred. A transparent report would allow readers to evaluate the outcome analysis and its limitations rather than infer them.

Finally, the registry includes several secondary outcome measures and mentions later follow-up questions. This makes clear why a prespecified statistical plan and transparent reporting of how multiple outcomes are interpreted matter. The record does not report that plan or those numerical findings. Statistically, the trial is informative as an example of a well-defined comparison whose posted design details do not, on their own, permit evaluation of the primary result.

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.

The primary limitation for interpretation is that the registry record does not report numerical results for the primary OAB-q symptom-bother outcome. No group means, standard deviations, comparative estimate, confidence interval, or p-value are available in the information. As a result, the primary efficacy question cannot be answered statistically from the posted record.

Reporting about the analysis is also limited. The record does not describe the model, whether the comparison used change from baseline or follow-up scores, whether baseline outcome values were adjusted for, or how repeated measurements were handled. It does not specify the analysis population or the method for dealing with missing measurements. The reason text accompanying the 12-week analysis counts is incomplete.

The record reports no masking, while the primary endpoint is a subjective questionnaire measure. This is a design feature to consider when interpreting such an outcome; the registry does not provide evidence about whether it affected participant responses. Details of the randomization process and allocation concealment are not reported in the information.

The registry lists multiple secondary outcomes and refers to 24-week and 52-week questions, but numerical results and multiplicity procedures are not reported. Safety reporting gives summary counts but not event descriptions, definitions, severity, timing, or an analysis comparing groups. Further eligibility details, dosing, adherence, and concomitant care are also not reported in the registry record. These gaps constrain assessment of both the findings and their reproducibility.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Detrol Long Acting (LA) vs Estrace Vaginal Cream for the Treatment of Overactive Bladder Symptoms — NCT00465894.
• Registry record last updated 2018-11-01; status last verified 2018-10.
• Results first posted 2012-10-23.
• 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

NCT00465894 is listed as a completed, randomized, unmasked, parallel-group trial sponsored by the University of Alabama at Birmingham. It enrolled 58 participants: 30 assigned to extended-release tolterodine LA and 28 assigned to intravaginal estradiol cream. The official title describes a study in post-menopausal women with overactive bladder symptoms.

The primary outcome was the OAB-q symptom-bother score, measured from baseline through 12 weeks. The registry describes a 0-to-100 scale, with higher scores indicating greater symptom bother. It reports baseline and 12-week analysis counts, but not numerical primary outcome results or a between-group estimate. Serious adverse events were recorded as zero in both groups; other adverse events were recorded for 17 of 30 and 6 of 28 participants, respectively.

The record lists 13 outcome measures and describes secondary questions involving later follow-up, but their numerical findings, analysis plan, and missing-data methods are not reported in the registry record.