This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Benefits of the Use of Botox in the Treatment of Empty Nose Syndrome Syndrome (NCT00732680), a na phase 1, phase 2 study. The primary outcome is Mean Score of Sino Nasal Outcome Test 22 (SNOT 22).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00732680 |
| Phase | Phase 1, Phase 2 |
| Condition | Empty Nose Syndrome, Atrophic Rhinitis |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 9 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Mayo Clinic |
| Results posted | Yes |
2. Clinical Question
Population
People with Empty Nose Syndrome were the intended population. Atrophic Rhinitis is also listed among the conditions. The registry lists enrollment of 9, but the record says no study data were collected.
Intervention
Botulinum Toxin Type A was the intervention. The description specifies 10 Units injected into the dilator nasalis muscle on each side of the nose.
Comparator
There was no concurrent comparator group in the listed design. The study is described as single-group, with allocation recorded as NA; the registry does not report a control intervention.
Primary question
The planned primary outcome was the mean SNOT 22 score, with a timeframe listed as 2 weeks after intervention, 2 months. The registry reports that no study data were collected, so it does not answer whether scores changed after intervention.
The clinical question was whether treatment with botulinum toxin type A would be associated with a change in sinonasal health-related quality of life among people with Empty Nose Syndrome. SNOT 22 was selected as the primary measure. It is a questionnaire about symptoms and quality of life in sinonasal disease, with lower total scores representing better health-related quality of life.
The design does not set up a randomized comparison between treatment and control. It is listed as a prospective case series and a single-group study, with no masking. That means the registry’s planned question is about the treated group, rather than a direct comparison of outcomes under alternative treatments. The record does not describe a comparator group or provide an estimate for any comparison.
Most importantly, the registry states that no study data were collected. It attributes stopping the study to the lead investigator moving to a new medical center. Thus, the record describes the intended question and outcome but supplies no observed SNOT 22 scores, change estimates, or clinical outcome analysis with which to answer that question.
3. Trial Design
The registry describes a prospective case series evaluating short- and long-term benefits of botulinum toxin type A for Empty Nose Syndrome. Its design fields identify a single-group model, no masking, and allocation recorded as NA. The study is listed as Phase 1 and Phase 2. Mayo Clinic is named as the sponsor, and the registry lists enrollment of 9.
The intervention description specifies 10 Units of botulinum toxin type A injected into the dilator nasalis muscle on each side of the nose. The record lists Empty Nose Syndrome and Atrophic Rhinitis as conditions. It does not describe a concurrent control group, random assignment, or a masked assessment. The study therefore should not be read as a randomized comparison, and any treatment-versus-control interpretation would be unsupported by the listed design.
The registry gives a start of 2008-12 and primary completion of 2009-11. The study status is terminated. The record explains that the lead investigator moved to a new medical center and that the study was stopped when he left. It also explicitly states that no study data were collected.
There is one listed primary outcome measure, mean SNOT 22 score, with the timeframe recorded as 2 weeks after intervention, 2 months. The record does not give outcome values or analyses. The reason for the planned timing, the intended follow-up procedures, and any detailed protocol for collecting the measure are not reported in the registry record. The record also does not report a statistical analysis plan, an enrollment rationale, or details of any interim review. Because the study ended without collected outcome data, its design description does not translate into an efficacy estimate.
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
| Stage | Botulinum Toxin Type A |
|---|---|
| STARTED | 9 |
| COMPLETED | 9 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: No study data was collected in the study. The Lead investigator moved to a new medical center; the study was stopped when he left.
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.
| Characteristic | Unit | Botulinum Toxin Type A |
|---|---|---|
| Participants analysed | 9 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 5 |
| Age, Categorical: >=65 years | Participants | 4 |
| Sex: Female, Male: Female | Participants | 4 |
| Sex: Female, Male: Male | Participants | 5 |
| Region of Enrollment: United States | participants | 9 |
6. Primary Endpoint
The registry lists the primary outcome as Mean Score of Sino Nasal Outcome Test 22 (SNOT 22), measured over 2 weeks after intervention, 2 months.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary outcome is the mean score on the Sino Nasal Outcome Test 22, abbreviated SNOT 22. The registry describes it as a validated measure of health-related quality of life in sinonasal disease. It contains 22 items, each scored from 0-5, and the total score can range from 0-110. Lower scores represent better health-related quality of life.
A questionnaire score can make a broad patient-reported experience measurable in a consistent way. A mean score can describe the average score in a group, while changes in scores across an assessment period can be used to describe change over time when the required observations are available. In general, an outcome measure is useful only if its scores are collected and the analysis makes clear which observations and time points are being summarized.
The registry lists the timeframe as 2 weeks after intervention, 2 months. That wording identifies the planned outcome timing but does not establish what assessments were completed. No SNOT 22 observations, mean scores, variability estimates, or analysis results are reported. The registry states that no study data were collected, so the primary endpoint cannot be evaluated from this record. A planned questionnaire endpoint is not itself evidence of a change in health-related quality of life.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical fact is that the registry reports no study data were collected. It therefore contains no observed SNOT 22 result from this study. There is no reported mean, change from baseline, variability estimate, confidence interval, test statistic, or p-value for the primary outcome. The record cannot quantify the direction, size, or precision of an outcome change.
This absence of results is different from a finding of no change. A null or near-zero estimated change would require collected observations and an analysis; neither is reported. Likewise, the record does not establish that the intervention improved or worsened the measured outcome. It documents a planned intervention and outcome, followed by termination before study data were collected.
The design information further limits what could have been concluded even if outcome data had been collected. The study is listed as a single-group prospective case series, with no masking and allocation recorded as NA. Without a concurrent comparison group, change in the treated group would not by itself separate an intervention-associated change from other explanations. General statistical point: a before-and-after observation can describe temporal change, but a causal claim needs a design and analysis that address alternative explanations. The registry does not report a randomized treatment comparison.
The record lists enrollment of 9, but enrollment alone is not an outcome analysis. The adverse-event fields list 9 at risk and 0 affected for both serious and other adverse events in the intervention group. Those safety counts do not provide information about SNOT 22 scores, and they should not be interpreted as efficacy results. They also should be read as registry-reported counts rather than as proof that an intervention is free of risk.
There is no reported analysis population, handling of missing observations, adjustment strategy, or statistical test for the primary outcome. In this case, the issue is not merely that some outcome values are missing from an otherwise analyzed dataset: the record says no study data were collected. As a result, no treatment effect estimate or precision assessment can be reconstructed from the record. Any numerical outcome claim would go beyond what it reports.
The record’s planning note describes sample-size illustrations based on an observed effect and assumptions including equal allocation between two arms. Those are planning calculations, not observed power. The listed clinical design, however, is single-group, and the record reports no collected outcome data. The planning note therefore does not supply a study result or resolve the absence of an analyzable treatment effect. The basis and interpretation of any particular planning value are not reported in the registry record.
9. Statistical Methods Explained
Several statistical ideas help distinguish what this record describes from what it can establish. The distinction is especially important when a trial is registered with a planned endpoint but ends without outcome data. The concepts below are general explanations; they do not imply that the study conducted the analyses described.
What does a single-group design estimate?
A single-group study observes people receiving an intervention without a concurrent control group. If measurements are collected at more than one time, the analysis may describe how outcomes in that group change across those assessments. Such a description is not automatically an estimate of what would have happened without the intervention. Changes may reflect the intervention, the course of the condition, other care, measurement variation, or other influences.
Randomization in a comparative study is one way to create groups whose differences are less likely to reflect systematic assignment choices. This record does not list random allocation or a comparator group; it identifies the model as single-group and allocation as NA. Consequently, it does not support a randomized treatment contrast. The registry does not report a statistical method intended to address alternative explanations for changes over time.
What do a mean and a confidence interval communicate?
In general, a mean is an average of observed values. It summarizes a group, but does not show the spread of individual outcomes or the precision of an estimate by itself. A confidence interval is a range calculated using data and a statistical method to communicate uncertainty around an estimate. Narrower intervals generally indicate greater precision under the assumptions of the method; wider intervals indicate more uncertainty. Neither an interval nor a mean can be obtained for this primary outcome from the registry record because no study data were collected and no outcome analysis is reported.
When an outcome is measured at multiple times, an analysis must also specify which observations are being compared. A change score, a follow-up mean, and a model that uses repeated observations answer related but distinct questions. The registry’s timeframe reads 2 weeks after intervention, 2 months, but does not report outcome observations or an analysis specification. It is therefore not possible to identify a calculated contrast or uncertainty interval.
Why does the comparator matter?
A comparison group can help distinguish change associated with treatment from change that might have occurred for other reasons. In a randomized trial, the treatment contrast is based on outcomes in assigned groups, subject to the analysis plan and data quality. In a single-group case series, a pre-intervention measurement, if collected, would not be a substitute for a concurrent randomized comparator. The registry record does not report a control intervention or randomized comparison.
The study’s planned intervention is described specifically as 10 Units injected into the dilator nasalis muscle on each side of the nose. That detail describes the intended treatment; it does not supply a measured response. Treatment details, design labels, and an outcome definition are necessary context, but they are not statistical results.
How should planning calculations be read?
General statistical explanation: a sample-size calculation uses assumptions about the outcome, target effect, variability, significance level, power, and design to illustrate how much information a future study might need. It does not show that a study reached that power, and it does not establish an observed effect. The planning note for this record describes illustrations based on an observed effect, a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The note says the effect to detect is a stated fraction of the observed effect. It also distinguishes total-event planning for time-to-event calculations from participants per arm for other calculations.
These planning assumptions should not be confused with the actual listed design, which is single-group. They do not create a comparator, and they do not replace missing outcome observations. The record gives no collected study data and no reported endpoint analysis. The source and details of any effect used for the planning illustrations are not reported in the registry record. Therefore, such illustrations are hypothetical planning quantities, not observed power or evidence of an intervention effect.
What does the absence of an analysis mean?
The registry lists 0 analyses. That is consistent with the explicit statement that no study data were collected. It means the record has no reported primary outcome analysis to interpret. It does not mean that an analysis found no statistically significant effect, because no outcome analysis is reported. General statistical practice would require clear definitions of the analysis population, outcome summaries, missing-data handling, and any model or test used. Those details are not reported in the registry record.
Over-dispersion is a general concern in some statistical models when observed variation exceeds what a model assumes. In such settings, uncertainty estimates may be too small if the extra variation is ignored. That issue cannot be assessed for this study’s primary outcome because there are no reported outcome data, model, or dispersion estimates. It would be inappropriate to attribute a particular model or adjustment to the study.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one primary outcome measure: mean SNOT 22 score. It also lists 0 analyses and states that no study data were collected. Thus, there are no reported outcome tests for which multiplicity adjustment can be assessed. The record does not report a statistical analysis plan, a hierarchy of outcomes, or a procedure for controlling the chance of false-positive findings across multiple tests. Those details are not reported in the registry record.
In general, multiplicity arises when many outcomes, time points, subgroups, or statistical tests are considered. Testing many hypotheses can make a chance finding more likely unless the analysis plan accounts for that multiplicity. A prespecified primary outcome can help focus interpretation, but merely listing an endpoint does not show how multiple analyses would have been handled. The timeframe is recorded as 2 weeks after intervention, 2 months; the record does not clarify how those listed timings would have entered an analysis.
For missing data, the distinction between incomplete follow-up and no collected study data matters. Here, the registry explicitly says no study data were collected and that the study was stopped when the lead investigator moved to a new medical center. It does not provide individual-level data, outcome summaries, or an account of partial collection. There is no basis in the record for estimating a missing-data pattern or applying a statistical method to address it.
The analysis population is not reported in the registry record. Neither an intention-to-treat population nor a per-protocol population is described. Without collected outcomes and an identified analysis population, readers cannot determine which participants would have contributed to a primary endpoint estimate. The enrollment figure does not establish an analyzed population or a completed endpoint dataset.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Botulinum Toxin Type A | 0 | 9 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Botulinum Toxin Type A | 0 of 9 |
For the Botulinum Toxin Type A group, the registry lists 9 at risk and 0 affected for serious adverse events. It also lists 9 at risk and 0 affected for other adverse events. No serious adverse-event terms are listed. These are the counts recorded in the safety fields; they are not primary outcome results.
The record’s statement that no study data were collected is important context when reading safety counts. The adverse-event fields do not explain how events were collected, the observation period for these counts, or how the safety information relates to the stated lack of study data. Those details are not reported in the registry record. The death count is not reported in the registry record.
In general, a reported count of zero affected participants does not demonstrate that an intervention has no risk. It is a registry-reported count within the listed group and should be interpreted in light of the study’s limited record and absent outcome dataset. The figures cannot establish that all possible adverse events were observed, nor do they provide a comparative safety estimate because no control group is listed.
12. What the Result Does, and Does Not, Mean
The record establishes that a prospective single-group case series was registered to evaluate botulinum toxin type A for Empty Nose Syndrome. It identifies the intended intervention, a primary patient-reported outcome, and a planned assessment timeframe. It also records that the study was terminated and that no study data were collected. These registry entries describe the study’s intent and its status, not an outcome of treatment.
The record does not establish a change in SNOT 22 score, the size or direction of any change, or the precision of an effect estimate. It does not report evidence for or against an outcome benefit. The absence of results is not equivalent to a statistically inconclusive result, and it is not evidence of no effect. It reflects the absence of collected study data and analysis in the registry record.
Even a completed single-group study would require careful interpretation. General statistical point: observations in one treated group can describe outcomes in that group, but without a suitable comparison they cannot reliably isolate the contribution of treatment from other explanations for change. In this case, the additional absence of collected outcomes means that even a within-group description is unavailable.
The reported adverse-event counts are also limited. The registry records 0 affected for serious and other adverse events in the intervention group, but provides no comparative safety estimate. These counts should not be expanded into a claim that the intervention is risk-free or that all safety outcomes were fully characterized.
In practical statistical terms, the record is informative about the planned design and why the study stopped, but not about treatment effects. The sample-size planning note does not alter that conclusion: planning illustrations are not observed power or outcome evidence. Any stronger clinical or statistical conclusion would require information not reported in the registry record.
13. Why This Trial Matters Statistically
This study matters statistically because it illustrates the difference between a registered research question and an answer supported by observed data. The record specifies a population, an intervention, and a primary questionnaire outcome. Yet the registry reports that no study data were collected. Without observations, even a clearly defined endpoint cannot yield an estimated mean, a treatment-associated change, or an uncertainty interval.
It also illustrates why design labels matter. A prospective case series and single-group model are not the same as a randomized comparison. A single-group study may describe outcomes over time when measurements exist, but it does not by itself provide the treatment-versus-control contrast that supports a comparative interpretation. Here, the record reports no outcome data at all, so neither a group description nor a causal comparison is available.
The registry’s safety counts offer a further statistical lesson: zero reported events should be described as a count, not as proof of absence of risk. Context about collection and follow-up matters, and that information is not reported in the registry record. The counts also cannot substitute for the primary outcome analysis.
Finally, planning calculations and observed study results answer different questions. A planning illustration can explore assumptions for a future design; it cannot recover results from a terminated study with no collected data. The registry’s planned endpoint and sample-size note therefore need to be kept separate from evidence about outcomes. This distinction helps readers interpret both completed analyses and records where the planned analysis never became possible.
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 most consequential limitation is that the registry states no study data were collected. There are consequently no reported SNOT 22 values, outcome summaries, effect estimates, or uncertainty intervals. The study was terminated after the lead investigator moved to a new medical center, according to the record. The reason recorded for stopping also means the registry cannot be read as a completed evaluation of the primary endpoint.
The listed design is a single-group case series with no masking and allocation recorded as NA. No comparator group is described. Even if outcome data had been available, a single-group design would limit comparative interpretation because changes could not be directly contrasted with outcomes in a concurrent control group. The registry does not report a method for addressing that limitation.
The primary outcome timing is listed as 2 weeks after intervention, 2 months, but the record does not describe completed assessments or clarify the timing further. It does not report baseline outcome values, follow-up completion, an analysis population, or a statistical analysis plan. Information about sample-size justification, interim analyses, and missing-data methods is not reported in the registry record.
The adverse-event fields list 0 affected for serious and other events, but the record does not describe the event-collection procedures or the period covered by those counts. It also does not report a death count. These omissions restrict interpretation of the safety record and do not support a comparative safety conclusion.
The planning note describes calculations using assumptions that include equal allocation between two arms, whereas the registered study model is single-group. The note does not provide an outcome result, and the record does not report the basis for the effect used in those illustrations. These planning details should not be mistaken for evidence that the study collected data or achieved a particular power.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Benefits of the Use of Botox in the Treatment of Empty Nose Syndrome Syndrome — NCT00732680.
- Registry record last updated 2016-04-18; status last verified 2016-03.
- Results first posted 2014-02-13.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT00732680 is a Mayo Clinic-sponsored prospective case series of botulinum toxin type A for Empty Nose Syndrome. The record lists Phase 1 and Phase 2, a single-group design, no masking, and enrollment of 9. The intervention description specifies 10 Units injected into the dilator nasalis muscle on each side of the nose.
The primary outcome is mean SNOT 22 score, with a timeframe listed as 2 weeks after intervention, 2 months. The study status is terminated. The registry says no study data were collected because the lead investigator moved to a new medical center and the study was stopped when he left. No primary outcome analysis is reported. The recorded adverse-event fields list 0 affected for serious and other events in the intervention group; the death count is not reported in the registry record.