Propel Stent vs Kenalog-soaked Nasopore After Frontal Drill-out: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Propel Stent vs Kenalog-soaked Nasopore After Frontal Drill-out (NCT03534362), a randomized na study. The primary outcome is Change From Baseline of Sino-Nasla Outcome Test (SNOT-22) Scores.

2. Clinical Question

The registry describes the broader rationale as assessing whether these steroid-containing devices differ in a larger frontal sinus operation in which one common cavity is created. It also mentions interest in scarring, but the registered primary outcome is SNOT-22 scores, not a direct measurement of scarring. The listed secondary outcomes concern postoperative complications involving devices and frontal sinus pathology.

The primary outcome title refers to change from baseline, while its description says the comparison is between mean postoperative scores. The record does not resolve that difference in wording. It lists follow-up after surgery at five occasions, from the early postoperative period through month 24. Because only one participant was enrolled, the registry does not report results, so this record cannot answer the comparative question from outcome data.

3. Trial Design

This was a randomized, single-masked, parallel-group study comparing two postoperative devices after frontal drill-out surgery. One group was assigned Kenalog-soaked Nasopore on the postoperative outflow tract; the other received a Propel stent at that site. The registry identifies the study as phase not applicable. It does not report who was masked, how randomization was generated or concealed, or whether any other measures were used to keep treatment assignment unknown.

The planned primary outcome was the comparison of postoperative SNOT-22 scores between groups, with follow-up after surgery at week 1–2, week 6–8, month 6, month 12, and month 24. The title of the outcome specifies change from baseline, whereas the description specifies mean postoperative scores. The record does not clarify whether the intended analysis was a change score, a comparison at particular visits, or another summary across follow-up.

Enrollment was 1. The study status is terminated. The recorded study start date is 2018-04-13, and the primary completion date is 2019-09-23. The registry says results are not reported because only one participant was recruited and enrolled and reporting could risk that participant’s confidentiality. It lists 0 analyses. The reason for termination and any details of the recruitment process are not reported in the registry record.

The registry lists postoperative complications involving devices and frontal sinus pathology as secondary outcomes. It does not provide their detailed definitions or report outcome results. The record also does not report a planned sample-size justification or the statistical analysis plan. The design description therefore identifies the randomized comparison and planned outcome, but does not establish how the investigators intended to handle repeated measurements, missing observations, or other analysis decisions.

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

Analysis population for the primary outcome, as defined in the registry: Because only 1 participant was recruited and enrolled, results are not reported in order to protect the confidentiality of the participant.

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.

Population: Only 1 subject enrolled

6. Primary Endpoint

The registry lists the primary outcome as Change From Baseline of Sino-Nasla Outcome Test (SNOT-22) Scores, measured over After the surgery, we will ask patients to follow up 5 times: post-operatively once between week 1-2, once between week 6-8, month 6, month 12, and month 24..

The primary outcome is titled change from baseline in Sino-Nasla Outcome Test (SNOT-22) scores. Its description says the aim is to compare mean postoperative SNOT-22 scores between the Propel stent and Nasopore groups. The registry does not give a unit, a summary parameter, a measure of dispersion, or a numerical result. It also does not explain how a change would be calculated or identify a single follow-up visit as the primary assessment.

In general, a patient-reported outcome can capture a participant’s account of symptoms or their impact, complementing clinical observations such as postoperative complications. Comparing scores between randomized groups can describe whether the observed outcome distributions differ, but interpretation depends on the definition of the score, the timing of measurement, and the analysis plan. Those details are not fully specified in this record.

The stated schedule includes five postoperative follow-ups: week 1–2, week 6–8, month 6, month 12, and month 24. Repeated measurements can describe outcomes at different stages of recovery, but they also require a clear plan for which visits and contrasts are primary. The registry record does not report such a plan. Although the rationale discusses scarring, the primary endpoint listed is SNOT-22 scores; the record does not identify a direct scarring measure as the primary endpoint.

No baseline or postoperative scores, changes, group means, uncertainty intervals, or statistical tests are reported. Thus the endpoint’s planned role can be described, but the comparative result and its precision cannot be assessed from the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Randomization and comparison. Random allocation is a general method for assigning participants to study groups by chance. Its purpose is to support a fair comparison by reducing systematic differences in group assignment. This trial is identified as randomized and parallel-group, with Propel and Kenalog-soaked Nasopore as the two study arms. The registry does not report the sequence-generation method, allocation concealment, or the identity of the person or people masked. With enrollment of 1 and no outcome results, randomization cannot yield a useful estimate of a between-group effect in the posted record.

What a treatment effect would represent. In general, a treatment effect is a defined contrast between outcomes under the study strategies. Here, the stated primary comparison concerns postoperative SNOT-22 scores. The outcome title says change from baseline, while the description says mean postoperative scores. Those descriptions imply different possible summaries, and the record does not say which one governs. It also does not identify a single visit or explain how measurements across the five follow-ups would be combined. Without these details and reported scores, no treatment-effect estimate can be interpreted.

Repeated follow-up measurements. The planned visits are week 1–2, week 6–8, month 6, month 12, and month 24 after surgery. In general, repeated measurements from the same participant are related rather than independent observations. Statistical methods for repeated data account for this dependence and must define how visits contribute to the primary contrast. A plan might focus on a particular visit or model the pattern over time, but neither approach should be assumed: the analysis plan is not reported in the registry record. The results are also withheld, so it is not possible to tell which measurements were collected.

Confidence intervals and p-values. In general, a confidence interval describes the uncertainty around an estimated effect, while a p-value summarizes how compatible the data are with a specified null hypothesis under the assumptions of a statistical test. Neither is reported for the primary outcome. More fundamentally, the registry does not report an outcome estimate to which such uncertainty measures could be attached. The record therefore supports neither a claim of statistical significance nor a claim of no difference.

Small samples and uncertainty. General statistical inference relies on observations that can support estimation of both group outcomes and their variability. With one participant enrolled, there is no reported group-level outcome comparison and no basis in this record for estimating the variability of SNOT-22 scores. Any numerical result derived from such limited information would be highly constrained, and the registry chose not to report outcome data for confidentiality. The appropriate reading is that the comparative effect and its precision are unavailable, not that the effect is zero.

Planning calculations. A sample-size calculation is a planning exercise that links a target effect, assumptions about variability, a significance level, allocation, and a desired power. In general, changing the effect assumed for planning changes the resulting sample-size requirement. The record says any planning illustration is based on fractions of an observed effect and uses a two-sided significance level of 0.05, equal allocation, and a normal approximation. Such illustrations do not describe the trial’s actual design justification and are not observed power. The registry does not report the trial’s own sample-size justification. Since outcome results are withheld, a reader should not treat an illustrative calculation as evidence about the treatment effect or the probability that the trial detected it.

Over-dispersion and count outcomes. In general, over-dispersion occurs when count data vary more than a chosen statistical model expects. It can affect uncertainty estimates and inference for count outcomes. The record lists postoperative complications among the secondary outcomes, but does not report their detailed definitions, a count-data model, or an analysis. There is no basis to state that over-dispersion was present or to say how complications would have been modeled.

Interpretation must follow the reported analysis. The registry lists 0 analyses and does not report results for the primary endpoint. It also does not report adjustment procedures, subgroup analyses, or interim analyses. A recalculation from summary statistics is not available because the relevant outcome summaries are absent. General statistical methods can explain what a future comparison might require, but they cannot supply the missing observations or determine the trial’s intended analysis.

10. Multiplicity, Missing Data and Analysis Populations

The primary outcome schedule includes five follow-up occasions, and the registry also lists two categories of secondary outcomes: postoperative complications involving devices and frontal sinus pathology. Multiple outcomes or repeated time points can create a multiplicity issue in general. If several comparisons are tested, the chance of at least one apparently unusual result can increase unless the analysis plan accounts for the number and structure of those tests. The registry record does not report whether a multiplicity adjustment was planned, which visit was primary, or how secondary outcomes would be handled.

Missing-data methods also cannot be assessed. The record does not report how many follow-up measurements were collected, whether any were missing, why data might be missing, or how missing observations would be handled. Because results were withheld, readers cannot evaluate completeness of follow-up. No imputation method or sensitivity analysis is reported in the registry record.

The analysis population is not specified. The record does not say whether the intended primary analysis would include all randomized participants, participants who received their assigned intervention, or another defined group. With enrollment of 1 and no reported outcome analysis, no population-specific estimate is available. The record also does not explain how the single enrollment was allocated or whether the participant completed follow-up; these details are not reported in the registry record.

These omissions limit assessment of how the planned analyses would control false-positive risk, address incomplete data, and preserve the randomized comparison. They do not establish that any particular analysis choice was made.

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.

The registry reports serious adverse-event counts of 0 participants at risk and 0 affected in the Nasopore group, and 1 at risk and 0 affected in the Propel group. Deaths are listed as 0 in both groups. For other adverse events, the Nasopore group has 0 at risk and 0 affected, while the Propel group has 1 at risk and 0 affected. No top serious-event terms are listed.

These are small registry counts, not comparative safety estimates. In particular, a zero affected count does not show that an event cannot occur or establish that the treatments have the same safety profile. The record reports only one participant enrolled overall and withholds outcome results to protect confidentiality. It does not provide detailed definitions, event descriptions, or additional safety analyses. The listed at-risk and affected counts should therefore be read as registry entries, with the limited information and denominator shown, rather than as evidence of a reliable difference or absence of risk.

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

The registry record establishes that a randomized, single-masked, parallel-group study was intended to compare Propel stent placement with Kenalog-soaked Nasopore after frontal drill-out surgery. Its primary outcome was postoperative SNOT-22 scores, and its planned follow-up schedule extended from the early postoperative period through month 24. The record also identifies postoperative complications involving devices and frontal sinus pathology as secondary outcomes.

What the record does not establish is the relative effect of the two approaches. Enrollment was 1, the study status is terminated, and the registry says results are not reported to protect the participant’s confidentiality. No primary outcome values, group comparison, confidence interval, or p-value is available. Therefore, the record does not show that the strategies produced the same results, that one produced better results, or that either result was clinically important.

The planned outcome and the broader study rationale should also be kept distinct. The rationale discusses scarring after a larger frontal sinus procedure, but the listed primary endpoint is SNOT-22 scores. The record does not provide a direct result for scarring, and it does not resolve the wording difference between the endpoint title’s reference to change from baseline and its description of mean postoperative scores.

The adverse-event entries do not provide a basis for comparative safety conclusions, given the very small counts and the lack of reported outcome results. Overall, this record documents the study question and design, but not an analyzable comparison of outcomes. Any claim about effectiveness, equivalence, or relative safety would exceed what the registry reports.

13. Why This Trial Matters Statistically

This trial matters statistically because it illustrates the difference between a registered research question and an answer supported by reported outcome data. Randomization describes how a comparison was intended to be made; it does not by itself produce an interpretable treatment-effect estimate. Estimation also requires outcome observations and enough information to describe the uncertainty around the comparison. The registry reports enrollment of 1 and no primary outcome results.

The record also shows why endpoint definitions matter. The primary outcome title refers to change from baseline, but its description refers to mean postoperative scores. Five follow-up occasions are listed, yet the record does not specify which occasion or summary would anchor the primary comparison. These choices define the question an analysis answers and affect how repeated observations should be interpreted.

Finally, planning calculations and observed results serve different purposes. A planning illustration based on an assumed effect cannot stand in for data from the randomized comparison, and it cannot establish what effect occurred. The registry does not report the trial’s own sample-size justification or analysis plan. With results withheld for confidentiality, the appropriate statistical conclusion is that the treatment contrast is not available from this record—not that the contrast is absent.

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 principal limitation is the very small enrollment: 1 participant. The registry states that outcome results are not reported to protect that participant’s confidentiality. As a result, the primary question cannot be evaluated from posted outcome data, and no estimate of effect or its precision is available. The terminated status further indicates that the study did not proceed to a reported group comparison; the reason for termination is not reported in the registry record.

The registry does not specify the details of masking, randomization procedures, or allocation concealment. It does not provide the analysis plan, sample-size justification, primary analysis population, missing-data approach, or multiplicity strategy. These details are important for assessing how the intended comparison would have been conducted, but their absence does not establish what the investigators did or did not do outside the registry record.

The primary outcome is not fully resolved in its wording: the title describes change from baseline, while the description states a comparison of mean postoperative scores. Although five follow-up occasions are listed, the record does not designate one as the primary assessment or explain how repeated measurements would be summarized. The listed secondary outcome categories are not accompanied by detailed definitions or reported results.

Finally, the adverse-event counts are too limited to support comparative safety interpretation, and no direct scarring result is reported. These are limits of the available record, not evidence that the outcomes were unchanged or that no events could occur.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Propel Stent vs Kenalog-soaked Nasopore After Frontal Drill-out — NCT03534362.
• Registry record last updated 2020-04-21; status last verified 2020-04.
• Results first posted 2020-04-21.
• 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 identifies NCT03534362 as a randomized, single-masked, parallel-group trial titled “Propel Stent vs Kenalog-soaked Nasopore After Frontal Drill-out.” St. Louis University is listed as the sponsor. The study is recorded as phase not applicable, with a start date of 2018-04-13, primary completion date of 2019-09-23, and status terminated.

The comparison was Propel stent placement versus Kenalog-soaked Nasopore after frontal drill-out surgery. The primary outcome was SNOT-22 scores, with five postoperative follow-up occasions listed. Secondary outcomes concern postoperative complications involving devices and frontal sinus pathology. Enrollment was 1. The registry states that results are not reported to protect participant confidentiality and lists 0 analyses. It does not report a sample-size justification, statistical analysis plan, or reason for termination.