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 The Effect of Wound Irrigation With Irrisept on Abscess Healing (Irrisept UF Study) (NCT04957732), a randomized na study. The primary outcome is Number of Subjects That Used Oral Antibiotics.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04957732 |
| Phase | NA |
| Condition | Abscess |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 35 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Irrimax Corporation |
| Results posted | Yes |
2. Clinical Question
The study asked whether pressurized irrigation with Irrisept, compared with pressurized irrigation using standard care with normal saline, affected abscess healing in patients presenting to an emergency department. The registry record describes oral antibiotic use as the measure used to assess healing. It lists assessments at the 24, 48, 72 and 96-hour visit intervals.
Population
Patients with abscesses presenting to the emergency department. The registry record describes the abscesses as uncomplicated in its account of the primary outcome.
Intervention
Irrisept Delivery System, described as Irrisept irrigation for participants assigned to the investigational group.
Comparator
Standard of Care, described as normal saline for participants assigned to the control group.
Primary question
How many participants used oral antibiotics at the listed follow-up intervals, and how did that outcome compare between the Irrisept and normal-saline groups?
The endpoint is not a direct measurement of wound dimensions or a time-to-healing measure. Instead, the registry record uses oral antibiotic use to determine whether the irrigation approach improved wound healing. Antibiotic use may reflect clinical judgments made during follow-up, so the outcome combines participants’ condition with decisions about whether to prescribe or use oral antibiotics.
The record identifies the study as randomized, which indicates that assignment to the two groups was intended to be by chance. It does not report the outcome counts or a statistical comparison for any of the listed visits. Therefore, the clinical question can be described, but the posted results do not establish how the groups differed on this outcome.
3. Trial Design
The record describes a randomized, parallel-group study of Irrisept Delivery System versus Standard of Care for abscesses. Standard of Care was normal saline; Irrisept was used in the investigational group. The record describes the irrigation as pressurized in its account of the primary outcome. Masking is listed as none, so the study is recorded as open-label rather than blinded.
Enrollment is listed as 35. The study began in 2010-01, and primary completion is listed as 2011-11. Its status is terminated. The registry record does not state why the study was terminated, whether the planned enrollment was reached, or how many participants were assigned to each group. A termination status by itself does not explain whether or how the study stopped, and no reason is reported in the registry record.
The record lists Abscess as the condition and identifies the study as phase NA. Its stated purpose was to evaluate the safety and effectiveness of Irrisept compared with standard care for skin and soft tissue infections in the form of abscesses. The sponsor is Irrimax Corporation.
The parallel design means that participants were assigned to one of the two irrigation groups rather than both groups in sequence. Random allocation can, in general, help balance participant characteristics across groups, but it does not guarantee balance in a small trial. The record does not report the method used to generate or conceal the random assignment sequence, the eligibility criteria in detail, or the number assigned to each arm.
There are 10 outcome measures listed, while no analyses are listed. The primary outcome is described at four follow-up intervals. The registry record does not report a protocol-level analysis plan, a prespecified sample-size justification, or an explanation for the termination. These omissions limit how fully the intended design and conduct can be reconstructed from the record.
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.
Before assignment: The planned sample size was 107 subjects enrolled in each arm. However, during the study, the site rearranged their ED and no longer treated abscesses. As a result, the study was terminated early after enrolling 35 subjects. Of those, 19 were on SoC and 16 were on Irrisept. A total of 30 subjects completed the study, with 12 subjects on Irrisept and 18 on SoC. For the 5 subjects that did not complete the study, 4 were on Irrisept and 1 on SoC.
Overall Study
| Stage | Standard of Care (SoC) | Irrisept |
|---|---|---|
| STARTED | 19 | 16 |
| COMPLETED | 18 | 12 |
| NOT COMPLETED | 1 | 4 |
Analysis population for the primary outcome, as defined in the registry: There were 4 timepoints for assessing abscess wound healing with the use of oral antibiotics: 24, 48, 72 \& 96 hours.
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: A total of 35 subjects were consented and randomized. There were no (0) screen failures. There were 16 subjects randomized to Irrisept and 19 to SoC. Of these, 12 subjects randomized to Irrisept and 18 subjects randomized to SoC completed the study.
| Characteristic | Unit | Standard of Care (SoC) | Irrisept | Total |
|---|---|---|---|---|
| Participants analysed | 18 | 12 | 30 | |
| Age, Categorical: Age - Known – <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Age - Known – Between 18 and 65 years | Participants | 18 | 12 | 30 |
| Age, Categorical: Age - Known – >=65 years | Participants | 0 | 0 | 0 |
| Sex/Gender, Customized: Male | Participants | 8 | 7 | 15 |
| Sex/Gender, Customized: Female | Participants | 9 | 6 | 15 |
| Sex/Gender, Customized: Unknown | Participants | 1 | 0 | 1 |
| Region of Enrollment: United States | participants | 18 | 12 | 30 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Subjects That Used Oral Antibiotics, measured over 24, 48, 72 & 96-hour visit intervals.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is titled Number of Subjects That Used Oral Antibiotics. It is a participant count, with the registry record specifying assessment at the 24, 48, 72 and 96-hour visit intervals. The record says oral antibiotic use was used to determine whether pressurized Irrisept irrigation improved wound healing compared with pressurized normal-saline standard care in uncomplicated abscesses.
Counting participants who used oral antibiotics can serve as an indirect indicator of the subsequent course of an abscess: the outcome records whether antibiotic use occurred rather than directly measuring wound closure, abscess size, or time to healing. In general, an outcome tied to treatment use can also reflect clinical decisions and local prescribing practice, not only the biological state of the wound. Because the study is recorded as having no masking, knowledge of assigned irrigation could potentially influence decisions; the record does not describe procedures intended to limit that possibility.
The repeated visit intervals matter for interpretation. A participant may have different antibiotic-use status at different visits, so a single overall count would not preserve the timing information. The registry record does not report the number of participants using antibiotics at any visit, nor does it report a group comparison for each interval. It also does not specify whether the primary analysis was intended to compare visits separately or combine them. Accordingly, the endpoint definition is available, but its observed values and analysis are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the primary outcome and its assessment schedule, but it does not report numerical results for oral antibiotic use at the 24, 48, 72 or 96-hour intervals. It also lists no analyses. Consequently, no effect estimate, confidence interval, or statistical test comparing Irrisept with normal saline is reported for the primary endpoint. The posted results therefore do not show the direction or precision of a difference between groups on this measure.
The outcome has multiple time points. Each visit could yield a distinct count, and those counts could be analyzed in different ways. The record does not report which approach was planned or used. The registry record notes that the primary outcome has several categories or time points and is not reduced to one comparison. Without reported counts and an analysis plan, readers cannot determine whether the treatment groups differed at a particular visit, whether any difference persisted, or how the repeated observations were handled.
Enrollment is listed as 35, but the record does not give the number analyzed for the primary outcome or the number assigned to each group. Enrollment alone cannot establish how many participants contributed data at each follow-up. The record does not report missingness, withdrawals, or exclusions from analysis. These details are important because incomplete follow-up can affect the interpretation of repeated outcome counts, particularly if missing observations differ between groups or depend on participants’ clinical status.
Adverse-event entries list zero serious events at risk and zero serious events affected in each group, with zero deaths in each group. For other events, the Standard of Care entry lists 18 at risk and 12 affected; the Irrisept entry lists 12 at risk and 6 affected. These entries describe the adverse-event information in the record and should not be mistaken for the primary endpoint results. The record does not provide additional detail about the event terms, severity, or timing in these entries.
A planning description states that sample-size illustrations use a two-sided significance level of 0.05, equal allocation, a normal approximation, and effects expressed as fractions of an observed effect; it distinguishes participants per arm from total event counts for time-to-event settings. However, the primary outcome is not reduced to one comparison, and a numerical observed effect for it is not reported. No numerical planning illustration can therefore be interpreted as a trial-specific estimate of the primary outcome’s precision. Such planning illustrations, where applicable, are not observed power and do not substitute for the trial’s missing outcome results.
9. Statistical Methods Explained
The record identifies a randomized, parallel-group design and an outcome recorded as the number of participants using oral antibiotics. Those details describe the broad design and endpoint, but they do not specify the statistical methods used to analyze the primary outcome. No analyses are listed, and the numerical primary outcome results are not reported in the registry record.
What randomization contributes
In general, randomization assigns participants by chance, which can reduce systematic differences in measured and unmeasured characteristics between treatment groups. It does not ensure that every characteristic is balanced, especially in a small study. The record lists enrollment as 35 but does not report group-specific enrollment, the random-sequence method, or allocation concealment. Therefore, the practical details and implementation of randomization cannot be assessed from the registry record.
The study is described as having no masking. In general, masking can reduce the influence of treatment knowledge on behavior, clinical assessments, and decisions about additional care. Because oral antibiotic use can involve a clinical decision, the absence of masking is relevant to interpretation. The record does not say whether prescribing criteria were standardized or whether outcome assessment was otherwise kept independent of treatment assignment.
How to understand a participant count
A count outcome records how many participants experienced or met a defined condition. Here, the defined condition is use of oral antibiotics, assessed at the stated visit intervals. A count is not automatically a rate or a proportion: to interpret the count as a proportion, the number of participants eligible for assessment at that visit is also needed. Group-specific denominators and outcome counts are not reported for the primary endpoint, so neither a proportion nor a comparison can be recovered from the registry record.
In general, a comparison of counts may use methods that account for the number of participants observed and the nature of the outcome. If each participant contributes a binary status at each visit, repeated measurements on the same participant are related rather than independent. Appropriate analysis may need to account for that within-participant relationship. The registry record does not identify a model, test, adjustment method, or strategy for handling repeated observations. It is therefore not possible to determine how the primary outcome was analyzed.
Why confidence intervals matter
In general, a confidence interval expresses the uncertainty around an estimated effect under the assumptions of the analysis. It can show which effect sizes are compatible with the data and method, rather than presenting only a single estimate. A confidence interval requires an estimate and its uncertainty; neither is reported for the primary outcome. No conclusion about the precision of the group comparison can be drawn from the endpoint description alone.
A p-value, in general, describes how incompatible observed data are with a specified null hypothesis under the assumptions of a statistical test. It is not the probability that a treatment is effective, nor does it describe the size or practical importance of an effect. No primary-outcome p-value or test is reported in the registry record. The trial’s statistical significance for the primary endpoint is therefore unknown from the posted results.
Repeated visits and multiplicity
When the same outcome is assessed at several time points, separate tests can create a multiplicity problem: as more tests are conducted, the chance of at least one apparently unusual result can increase. General approaches include prespecifying a primary time point, adjusting for multiple comparisons, or using a repeated-measures model that estimates a pattern over time. The record names four assessment intervals but does not report a testing hierarchy, multiplicity adjustment, or repeated-measures method. These are possible general approaches, not methods confirmed for this study.
The listed planning assumptions describe a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the effect to detect expressed as a fraction of an observed effect. This is a planning framework, not evidence of the analysis actually used. The record does not report the study’s own sample-size justification, a numerical effect assumption, or a numerical sample-size result. It also does not establish that the study’s design had a particular power. Planning calculations should not be described as observed power.
Because the primary endpoint has several time points and the record does not present one reduced comparison, a planning illustration based on a single observed effect cannot be connected to a reported primary-outcome estimate. The record gives no analysis results from which to recalculate an unadjusted comparison. Any such estimate, model, or significance statement would require information not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The primary outcome is assessed at four intervals: 24, 48, 72 and 96 hours. Multiple assessments create a statistical question about how the visits were intended to contribute to the main conclusion. In general, testing each visit independently can increase the chance of a false-positive finding across the set of tests. A prespecified primary visit, a multiplicity adjustment, or a model for repeated measures are possible strategies, but the registry record does not report whether any of these was planned or used.
The record lists 10 outcome measures, including secondary outcomes concerning oral antibiotic use in relation to erythema area, induration or abscess area, warmth, and fluctuance. It does not report a testing hierarchy or describe how results across those measures would be interpreted together. No analyses are listed, and there are no reported primary-outcome comparisons. The record therefore does not establish whether multiplicity was addressed in the study’s analysis.
Information about missing data is also not reported in the registry record. There are no primary-outcome denominators by visit, counts of participants with missing assessments, or explanations for missingness. The record does not state whether participants who lacked a visit assessment were excluded, handled through an imputation method, or included in another analysis. It also does not describe the analysis population, such as whether all randomized participants were intended to be analyzed in their assigned group.
These gaps affect interpretation without proving that any particular approach was or was not used. For repeated outcomes, denominators and missingness by visit help clarify how much information contributed to each comparison. An analysis population and missing-data strategy help define what question the estimate would answer. Since those details and the outcome results are not reported, the primary endpoint’s analytic population, completeness, and multiplicity handling remain unclear.
11. What the Result Does, and Does Not, Mean
The registry record establishes that a randomized comparison of Irrisept irrigation and normal-saline standard care was planned for abscesses, and that oral antibiotic use was designated as the primary measure related to healing. It also identifies the four follow-up intervals and reports that the study status is terminated. These details describe the study question and record status, not the effect observed on the primary outcome.
The posted results do not report primary outcome counts, group-specific denominators, effect estimates, confidence intervals, or a statistical test. As a result, they do not establish whether oral antibiotic use was more or less common in either group, whether the groups were similar, or how precisely any difference was estimated. Absence of a reported result is not evidence that the groups had identical outcomes, and it is not evidence that one irrigation approach had a particular effect.
The adverse-event entries are limited in what they can establish. They list zero serious events at risk and affected, and zero deaths, for both groups. They also list other-event counts for each group. The record does not provide further event descriptions or a primary endpoint analysis. These adverse-event entries should not be treated as proof of comparative safety or as substitutes for the missing efficacy outcome results.
General statistical interpretation requires more than knowing the trial’s design and endpoint definition. It depends on observed outcomes, the number assessed, the comparison method, and uncertainty around the estimate. For this study, these elements are not reported for the primary endpoint. The record also does not explain the reason for termination or whether all planned follow-up and analyses were completed.
Accordingly, the appropriate conclusion is limited: the registry record describes a randomized study of two irrigation approaches and specifies oral antibiotic use at four intervals as the primary outcome, but does not report the primary outcome findings needed to judge the observed comparison. No treatment recommendation or conclusion about clinical benefit follows from the record’s endpoint description alone.
12. Why This Trial Matters Statistically
This trial is statistically notable because the registry record describes a clear randomized comparison but does not report the numerical results for its primary endpoint. The contrast is between a defined intervention, Irrisept Delivery System, and a defined control, normal-saline standard care. Yet without group-specific counts and an analysis, readers cannot estimate the size or precision of the comparison the study set out to make.
The endpoint also illustrates how clinical outcomes can be indirect. Oral antibiotic use was selected as a way to assess abscess healing, but it records a treatment-use decision rather than a direct wound measurement. In general, such outcomes can reflect both participants’ condition and clinical practice. The study is recorded as unmasked, making the absence or presence of standardized prescribing criteria relevant; those criteria are not reported in the registry record.
Repeated assessment at four intervals raises a separate design and analysis issue. A result at one visit may not answer the same question as a pattern across visits. Without a reported analysis plan, outcome counts, and missing-data information, it is impossible to know how the timing of assessments was incorporated or how results across time points were interpreted.
The record also emphasizes why enrollment is not a substitute for outcome reporting. Enrollment is listed as 35, but group sizes and numbers assessed at each visit are not reported. Readers therefore cannot infer the amount of information available for the primary comparison from enrollment alone.
More broadly, this record demonstrates the distinction between a stated research question and an interpretable result. Randomization and endpoint definitions establish the intended comparison, while outcome data and statistical methods are needed to quantify what the study found. In their absence, a careful statistical account must preserve that uncertainty rather than infer an effect.
13. 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 interpreting this particular study is that the registry record does not report the primary outcome values or a comparison between groups. Although the outcome and four assessment intervals are named, there are no corresponding participant counts, effect estimates, confidence intervals, or tests. The record also lists no analyses. This prevents assessment of the direction, magnitude, and precision of the primary result.
Enrollment is listed as 35, but group-specific enrollment and the number assessed at each visit are not reported. The registry record does not describe missing follow-up, exclusions, withdrawals, or the population included in any analysis. It is therefore not possible to assess completeness of primary outcome data or determine how participants were handled in analysis.
The study is recorded as unmasked. The endpoint is oral antibiotic use, which may involve clinical judgment, but the record does not describe prescribing criteria or safeguards against knowledge of group assignment affecting decisions. This is a potential interpretive concern, not evidence that any such influence occurred.
The primary outcome has several time points, and the record does not explain how they were combined or compared. No multiplicity strategy, statistical model, or analysis plan is reported. The status is terminated, but the reason for termination and its implications for the planned study are not reported in the registry record. These limitations restrict interpretation of both the study’s conduct and its findings; they do not establish what results would have been observed under a different design or analysis.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: The Effect of Wound Irrigation With Irrisept on Abscess Healing (Irrisept UF Study) — NCT04957732.
- Registry record last updated 2022-02-02; status last verified 2022-01.
- Results first posted 2022-02-02.
- 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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17. Record Summary
NCT04957732 is a randomized, parallel-group study of Irrisept Delivery System versus Standard of Care with normal saline for abscesses. It is recorded as unmasked, with enrollment of 35 and status terminated. The study began in 2010-01, and primary completion is listed as 2011-11. Irrimax Corporation is the listed sponsor.
The primary outcome is the number of participants using oral antibiotics, assessed at the 24, 48, 72 and 96-hour visit intervals. The registry record lists 10 outcome measures but no analyses. It does not report numerical primary outcome results, group-specific denominators, or a comparison estimate. The reason for termination, the study’s own sample-size justification, analysis populations, and missing-data methods are not reported in the registry record. The posted information defines the research question but does not permit a statistical conclusion about the primary comparison.