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 TissuePAtchDS--P ™ PArotidectomy Trial. (NCT04116762), a randomized na study. The primary outcome is Proportion of Participants Discharged at Day 0 Following Superficial Parotidectomy.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04116762 |
| Phase | NA |
| Condition | Parotid Gland Disorders |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 3 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Poole Hospital NHS Foundation Trust |
| Results posted | Yes |
2. Clinical Question
Population
The study concerns people having superficial parotidectomy for a benign tumour near the surface of the parotid gland. The registry describes the condition as parotid gland disorders and identifies the primary outcome population specifically as non-randomised pilot-phase data. The record does not report further eligibility details for the participants whose primary outcome is posted.
Intervention
The intervention is placement of TissuePatchDS-P™ at the operation, with no surgical drain. The study rationale is that an adhesive sealant might close the space left after gland removal and limit fluid build-up. The registry describes same-day discharge and fewer complications as potential aims, not as established findings.
Comparator
The comparator is closure with a surgical drain in place, without TissuePatchDS-P™. The registry says the surgeon chooses the drain. Although the trial is recorded as randomized, the posted primary outcome has no control-group observation, so the intended comparison cannot be estimated from these results.
Primary question
The primary question is whether participants are discharged on the day of superficial parotidectomy, described as day 0 in the outcome title and description. Same-day discharge is relevant to the study’s aim of assessing day-case surgery. The outcome timeframe is recorded as “Day one,” however, so the registry wording does not fully align on the timing label. The primary data are explicitly identified as non-randomised pilot-phase data.
3. Trial Design
This study is recorded as a randomized, parallel-group superiority trial comparing TissuePatchDS-P™ with a surgical drain after benign superficial parotidectomy. Masking is listed as none. The sponsor is Poole Hospital NHS Foundation Trust. The study began on 2018-11-30, had a primary completion date of 2019-10-01, and is marked terminated. The recorded enrollment is 3.
The posted primary outcome is not described as a result from the randomized comparison. Its population is specified as non-randomised pilot phase data only. The intervention arm has 3 participants and a reported count of 3 discharged at day 0; the control arm has 0 participants and no reported outcome count. Consequently, the registry does not provide observations from both groups for the primary endpoint, despite the randomized design recorded for the trial.
The intervention consists of applying TissuePatchDS-P™ during the operation without a drain. The control procedure uses a surgical drain and no sealant. The trial’s stated rationale is to assess whether sealant use could permit day-case discharge and reduce complications associated with drains. Those aims explain the comparison but do not establish that either approach achieves those outcomes.
The registry lists two secondary outcomes: number of complications and the EORTC QLQ-HN35 quality-of-life questionnaire. It records three outcome measures overall, but does not report comparative analyses. The protocol details, including the planned statistical analysis and the reason for termination, are not reported in the registry record. It is therefore not possible to determine from the record whether the posted pilot data were intended to support the planned randomized trial analysis or how the trial would have proceeded after the pilot phase.
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 | Intervention | Control |
|---|---|---|
| STARTED | 3 | 0 |
| COMPLETED | 3 | 0 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Non-randomised pilot phase data only.
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: Within 72 hours, all patients developed sialocoele \& pilot study was closed. None of the outcome measures reported in this record were collected at baseline: 1. Proportion of participants discharged at day 0 following superficial parotidectomy was first assessed post-operatively; 2. Number of complications was first assessed 3 months post-operatively 3. EORTC Quality of Life Question was administered once 3 months post-operatively
| Characteristic | Unit | Intervention | Control | Total |
|---|---|---|---|---|
| Participants analysed | 3 | 0 | 3 | |
| Age, Categorical: <=18 years | Participants | 0 | — | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 3 | — | 3 |
| Age, Categorical: >=65 years | Participants | 0 | — | 0 |
| Sex: Female, Male: Female | Participants | 1 | — | 1 |
| Sex: Female, Male: Male | Participants | 2 | — | 2 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: United Kingdom | participants | 3 | — | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Proportion of Participants Discharged at Day 0 Following Superficial Parotidectomy, measured over Day one.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the count of participants discharged at day 0 following superficial parotidectomy. In practical terms, it concerns whether discharge occurs on the day of surgery, rather than after an inpatient stay. The registry describes the outcome as a proportion, while the posted measure is a participant count. The outcome title and description refer to day 0, but the listed timeframe is “Day one”; this difference in wording leaves the precise timing label unclear.
Same-day discharge is used as an outcome because the study asks whether the sealant approach could support day-case parotid surgery. The study background describes routine admission while a surgical drain remains in place and proposes that sealing the surgical space could reduce the need for a drain. This endpoint addresses discharge timing directly. It does not by itself measure whether fluid collection, infection, fistula, quality of life, or other complications differ between approaches.
The intervention group has a reported count of 3, with 3 participants in that group; the control group has no participants with a posted primary outcome. There is therefore no two-arm estimate of the difference in discharge outcomes. The endpoint data are identified as non-randomised pilot-phase data, so they should not be interpreted as a comparative randomized-trial result.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary outcome records 3 participants in the intervention arm and a count of 3 discharged at day 0. The control arm has 0 participants and no reported outcome value. This describes the pilot-phase observations recorded for the intervention group; it does not establish how discharge outcomes compare with surgical drainage. The primary outcome population is explicitly described as non-randomised pilot-phase data, which further limits interpretation as evidence from the randomized comparison.
A comparative effect requires outcome information from both groups. With no control observations, the registry cannot support an estimate of the difference between sealant and drain groups, nor a confidence interval describing uncertainty around that difference. The posted results also do not include a comparative test or p-value. The record notes that values are missing or not estimable for a two-arm comparison of the binary endpoint. This is a limitation of the available outcome data, not evidence that the groups have equivalent outcomes.
The arm count and endpoint count are small and confined to the intervention group. Such sparse data offer little basis for judging how consistently the outcome might occur in a broader study population. General statistical principle: a confidence interval expresses the range of effects compatible with the data under the analysis assumptions. No two-group interval can be meaningfully reported from these posted primary outcome data because one group has no observations. A count in a small, single-group pilot does not substitute for that missing comparison.
The record also lists complication and quality-of-life outcomes, but comparative findings for them are not reported in the registry record. Safety entries show no serious adverse events in the three intervention participants at risk, and three other adverse events in that group. The nature of those other events is not specified in the posted record. The control group has no participants at risk for the posted safety counts, so these figures do not permit a safety comparison.
The trial status is terminated, and enrollment is recorded as 3. The reason for termination is not reported in the registry record. The data should therefore be read as a limited pilot-phase description, rather than as a completed randomized superiority analysis. They neither demonstrate nor rule out a difference in discharge outcomes or complications between the two approaches.
9. Statistical Methods Explained
The registry describes a randomized, parallel-group superiority design with no masking. General explanation: in a parallel-group trial, participants are assigned to one of the study approaches and outcomes are compared between groups. A superiority analysis asks whether one approach has better outcomes than the other under the prespecified endpoint and analysis. The registry record does not report the full statistical analysis plan, including the exact comparison method or the planned handling of the pilot phase.
What kind of outcome is recorded?
The primary outcome is binary at the participant level: a participant either meets the discharge outcome or does not. The posted measure is a count of participants with the outcome, rather than a reported group proportion or a comparative effect. General explanation: binary outcomes are often presented as event counts and denominators, with a group-level proportion or a between-group effect measure used for comparison. Here the intervention group has 3 participants and a count of 3; the control group has 0 participants and no outcome count. A comparative estimate is therefore not available.
The registry’s outcome description identifies the measure as the proportion discharged at day 0, while the recorded result is a count. It also labels the timeframe “Day one,” although the outcome title and description refer to day 0. These descriptions should be kept distinct rather than silently treated as identical. The registry record does not explain the difference in timing labels.
Why is a two-group estimate unavailable?
A between-group effect needs outcome information for both the intervention and control groups. With no control participants in the posted primary outcome, a difference, relative effect, or confidence interval for the randomized comparison cannot be estimated from these data. The registry explicitly indicates that a two-arm comparison is not estimable for this binary endpoint. This absence is not a zero treatment effect and is not evidence of equivalence. It means that the posted outcome cannot answer the comparative question.
General explanation: uncertainty is especially important when event counts are sparse. A confidence interval communicates how imprecise an effect estimate may be, rather than presenting a single estimate as if it were exact. If the data do not support an effect estimate, an interval cannot repair the absence of a comparison. The registry record does not report a confidence interval or a comparative p-value for the primary endpoint.
What do the planning assumptions mean?
The sample-size planning illustration is described as using the observed effect, two-sided significance level 0.05, equal allocation, and a normal approximation, with the target effect set to a stated fraction of the observed effect. These are planning assumptions, not reported features of the trial’s own design justification. The registry record does not report the trial’s sample-size justification. Nor should a planning illustration be read as observed power: it describes a hypothetical design calculation, not the probability that this trial detected an effect. Because a two-arm primary effect is not estimable from the posted data, any planning interpretation based on an observed effect warrants particular caution.
General explanation: power calculations depend on assumptions about the outcome, effect size, significance level, and allocation. When an effect estimate is unstable or unavailable, calculations derived from it may also be unstable or not interpretable. The record does not report a prespecified effect size or explain how the planning illustration relates to the protocol. No interim analyses or stopping rules are reported in the registry record.
How should safety counts be understood?
Safety counts include the number at risk and the number affected. The serious-event entry lists 3 intervention participants at risk and 0 affected; it lists 0 control participants at risk. The other-adverse-event entry lists 3 intervention participants at risk and 3 affected, with 0 control participants at risk. General explanation: counts describe what was recorded in the observed group, while a comparative safety assessment requires suitably observed participants in both groups and clear definitions of the events. The nature and severity breakdown of the other adverse events are not reported in the registry record.
The record provides no analyses for the posted outcomes. The exact statistical tests, model specifications, covariate adjustments, confidence-interval methods, and missing-data procedures are not reported in the registry record. Those omissions prevent reconstruction of a planned analysis. The results should therefore be interpreted descriptively, without assigning statistical significance or claiming a treatment effect.
10. Exact Estimates for Each Arm
No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.
| Arm | Participants | Events | Observed % | Clopper-Pearson 95% CI | Wilson 95% CI | Bayesian 95% credible interval |
|---|---|---|---|---|---|---|
| Intervention | 3 | 3 | 100.0% | 29.2% to 100.0% | 43.9% to 100.0% | 39.8% to 99.4% |
R code and output
arm <- c("Intervention")
n <- c(3)
events <- c(3)
for (i in seq_along(n)) {
ci <- binom.test(events[i], n[i])$conf.int # Clopper-Pearson exact interval
cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i]) # Bayesian, uniform Beta(1,1) prior
wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}
ARM Intervention 3 3 100.0 29.2 100.0 43.9 100.0 39.8 99.411. Multiplicity, Missing Data and Analysis Populations
The registry lists two secondary outcomes: number of complications and the EORTC QLQ-HN35 quality-of-life questionnaire. It records three outcome measures overall, but comparative analyses are not posted. A multiplicity strategy for evaluating several outcomes is not reported in the registry record. General explanation: when several outcomes or hypotheses are tested, the chance of at least one apparently notable result can increase, so a prespecified approach to multiplicity can help frame interpretation. No such approach can be inferred from the list of outcomes alone.
Missing-data handling is not reported in the registry record. The primary endpoint has no control observations, but the record does not explain whether this reflects non-enrollment in the control arm, unavailable outcome data, or another reason. It would be inappropriate to classify those absent observations as either successes or failures. The reason the trial was terminated is also not reported.
The analysis population definitions are not reported in the registry record. In particular, the record does not specify whether an intention-to-treat, per-protocol, or other analysis population was planned. The primary outcome is identified as non-randomised pilot-phase data only, so it should not be treated as a randomized analysis population. The record also does not report how participants were assigned for the pilot phase or whether any participants were excluded from an analysis.
These gaps matter because the analysis set, missing outcomes, and multiplicity plan can affect how estimates should be interpreted. With no reported two-arm analysis and no control outcome data, the central comparative question remains unanswered regardless of how the unreported procedures might have been specified.
12. 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 |
|---|---|---|---|
| Intervention | 0 | 3 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Intervention | 0 of 3 |
| Control | 0 of 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 |
|---|---|
| Intervention | 3 of 3 |
| Control | 0 of 0 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Intervention | Control |
|---|---|---|---|
| Sialocoele | Skin and subcutaneous tissue disorders | 3 of 3 | n/a of 0 |
The serious adverse event figures list 3 intervention participants at risk, 0 serious adverse events affecting participants, and 0 deaths. The control group has 0 participants at risk and 0 affected. These entries describe the posted counts; they do not establish comparative safety because no control participants contribute to the safety count.
The separate other-adverse-event figures list 3 intervention participants at risk and 3 affected. The control group again has 0 participants at risk. The registry does not identify the specific other adverse events in this record, so their clinical nature cannot be assessed from the posted figures. The registry also lists no top serious-event terms.
General explanation: the number at risk is the denominator needed to interpret an event count. An absence of recorded serious events in a small observed group is not proof that serious events cannot occur, and a count from one group cannot establish a difference between treatments. These figures should be read as descriptive safety reporting for the participants recorded, not as evidence that one approach is safer or less safe than the other.
13. What the Result Does, and Does Not, Mean
The registry records a count of 3 participants discharged at day 0 among 3 participants in the TissuePatchDS-P™ arm. It does not post a control-group outcome count: the control arm has 0 participants in the primary outcome record. The primary outcome is explicitly limited to non-randomised pilot-phase data. These registry entries describe a small set of pilot observations, not a randomized comparison of sealant with surgical drainage.
The result does not show that TissuePatchDS-P™ increases same-day discharge compared with a drain, because there is no control outcome against which to make that comparison. It also does not show that the approaches have the same outcome. No comparative effect estimate, confidence interval, or p-value is reported. The data cannot establish the size or precision of any difference.
The study rationale also refers to complications associated with drains, and the registry lists complications and quality of life as secondary outcomes. The posted data do not provide comparative results for those outcomes. The safety entries are descriptive and lack control participants at risk. The three other adverse events in the intervention group are not characterized by event type in the record.
General explanation: a pilot study can describe feasibility or generate information for further research, but a small or incomplete set of observations does not by itself answer an efficacy or safety comparison. The record does not state the intended role of these particular pilot data beyond identifying them as non-randomised pilot-phase data. It is therefore safest to restrict conclusions to the counts that are actually posted and avoid extending them to the planned randomized superiority question.
The trial is marked terminated, with recorded enrollment of 3. The registry record does not report the reason for termination or a completed comparative statistical analysis. The findings neither establish a treatment benefit nor demonstrate an absence of benefit. They leave the comparative question unresolved.
14. Why This Trial Matters Statistically
This trial illustrates the difference between a randomized design recorded in a registry and the data available for a randomized comparison. The study is listed as randomized and parallel-group, yet the primary outcome population is explicitly described as non-randomised pilot-phase data. The intervention group has observations, while the control group has none in the posted primary outcome. Design labels alone cannot replace outcome data from both groups.
It also shows why a count needs its denominator and a comparison needs both arms. A count of 3 for the discharge outcome among 3 intervention participants is a useful description of the recorded pilot observations. It cannot quantify a contrast with surgical drainage when the control group has 0 participants. Reporting a comparative estimate under those conditions would imply information that the record does not contain.
The missing comparison also affects interpretation of precision. General explanation: confidence intervals and hypothesis tests summarize uncertainty about an estimated contrast; they do not create evidence when one group’s observations are absent. The registry’s indication that the binary comparison is not estimable is therefore a substantive constraint, rather than a minor reporting detail.
Finally, the listed safety counts emphasize the distinction between observed events and comparative safety conclusions. The other-adverse-event count is recorded only for the intervention participants, while the control group has no participants at risk. This trial’s registry record is a useful example of why outcome population, denominators, analysis status, and study termination should be considered alongside the nominal trial design.
15. 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 central limitation is that the posted primary endpoint does not include control participants. The intervention group has 3 participants and a discharge count of 3, while the control group has 0 participants and no outcome value. A between-group estimate cannot be made from these records. The endpoint population is identified as non-randomised pilot-phase data, so it cannot be treated as the randomized comparison described by the trial design.
Enrollment is recorded as 3 and trial status is terminated. The registry record does not report why the trial was terminated, whether additional enrollment was planned, or whether participants were excluded from the posted analysis. It does not report a sample-size justification, the planned analysis population, an analysis plan, interim analyses, or missing-data procedures. These omissions prevent assessment of whether the available observations followed the intended protocol.
The primary outcome wording is not fully consistent: the title and description refer to day 0 discharge, while the timeframe is recorded as “Day one.” The record does not explain the discrepancy. The secondary outcomes are listed, but their comparative results are not reported in the registry record. The other adverse events are not described by event type, and the safety record has no control participants at risk.
These limitations restrict interpretation to the posted descriptive counts. The record does not support a precise estimate of comparative discharge, complication, quality-of-life, or safety outcomes.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: TissuePAtchDS--P ™ PArotidectomy Trial. — NCT04116762.
- Registry record last updated 2026-11-05; status last verified 2026-08.
- Results first posted 2026-11-05.
- 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.
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19. Record Summary
NCT04116762 is a randomized, parallel-group, unmasked superiority trial sponsored by Poole Hospital NHS Foundation Trust. It compares TissuePatchDS-P™ without a drain against a surgical drain after benign superficial parotidectomy. The trial started on 2018-11-30, has a primary completion date of 2019-10-01, is marked terminated, and records enrollment of 3.
The primary outcome concerns discharge at day 0 and is identified as non-randomised pilot-phase data. The intervention arm records 3 participants and a discharge count of 3; the control arm records 0 participants and no outcome value. A two-arm binary comparison is not estimable from these data. The registry also lists complications and EORTC QLQ-HN35 quality of life as secondary outcomes, without comparative analyses. The reason for termination and the planned statistical analysis are not reported in the registry record.