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 Influence of IPV on GOR in Infants From 0 to 12 Months. (NCT02124863), a na na study. The primary outcome is Number of Refluxes.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02124863 |
| Phase | NA |
| Condition | Gastro-oesophageal Reflux |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 67 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Vrije Universiteit Brussel |
| Results posted | Yes |
2. Clinical Question
Population
Infants from 0 to 12 months receiving intrapulmonary percussive ventilation (IPV) for whom reflux counts were measured. The registry describes all patients receiving IPV as their own controls; a more detailed eligibility definition is not reported in the registry record.
Intervention
IPV, described as an airway-clearance technique and registered as a device intervention. The arm description specifies a 20-minute period of IPV at a rate of 300/min and p = 10cmH2O, at least 120 min after feeding.
Comparator
For each patient, reflux counts during IPV were to be compared with that patient's mean reflux count during 20-minute periods outside IPV. The description says counts were measured every two hours after feeding. This is a within-patient comparison, not a randomized comparison between separate treatment groups.
Primary question
Does the number of refluxes during 20 minutes of IPV differ from the mean number during the other 20-minute measurement periods? The registry frames the purpose as determining whether IPV provokes or aggravates reflux. It does not report the numerical counts, a contrast between measurement conditions, or an inferential result.
The clinical question is about a short-term count measured during a defined IPV session and compared with reflux counts measured at other times in the same infants. That framing matters: each infant contributes to both sides of the comparison, so the intended contrast is not equivalent to comparing unrelated groups. The registry does not state whether the primary analysis used a paired statistical procedure, how repeated observations were handled, or how many observations contributed per infant.
3. Trial Design
The registry record identifies a completed, single-group study with an enrollment of 67. Its title and summary concern IPV and gastro-oesophageal reflux in infants from 0 to 12 months. The intervention is IPV, registered as a device. The study status is completed; the recorded start is 2013-09 and the primary completion is 2015-01.
The design description says that patients receiving IPV were their own controls. Reflux counts were to be observed during 20 minutes of IPV and compared with a mean count during 20-minute periods outside IPV. Those other measurements were described as occurring every two hours after feeding. The IPV measurement was specified as occurring at least 120 min after feeding, at a rate of 300/min and p = 10cmH2O.
Allocation is listed as NA, masking as none, and the model as single group. The record therefore does not describe randomized allocation or masking. It also flags that the listed IPV and Control arms are not a like-for-like control comparison. The control wording in the safety record should not be mistaken for evidence of a separate randomized control group: the primary design description instead identifies within-patient controls.
The registry does not report a fuller protocol description, the sequence or timing of observations beyond the statements above, or the statistical plan. The study phase is listed as NA. Enrollment and completion status describe the record's conduct status, but do not supply the number of infants with usable endpoint measurements or analyzed data.
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 | Intrapulmonary Percussive Ventilation |
|---|---|
| STARTED | 67 |
| COMPLETED | 50 |
| NOT COMPLETED | 17 |
Analysis population for the primary outcome, as defined in the registry: All patients receiving IPV were their own controls
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 | Intrapulmonary Percussive Ventilation |
|---|---|---|
| Participants analysed | 50 | |
| Age, Categorical: <=18 years | Participants | 50 |
| Age, Categorical: Between 18 and 65 years | Participants | 0 |
| Age, Categorical: >=65 years | Participants | 0 |
| Gender: Female | Participants | 25 |
| Gender: Male | Participants | 25 |
| Region of Enrollment: Belgium | participants | 50 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Refluxes, measured over during 20 minutes of IPV compared to mean number of refluxes during 20 minutes..
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | number of refluxes |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is the number of refluxes, a count measured over a 20-minute period. The registry identifies the outcome as continuous and specifies a mean and standard deviation as its summary form. The primary comparison is the count during 20 minutes of IPV against the mean count during 20-minute periods outside IPV. The record says the latter measurements were taken every two hours after feeding and that each patient receiving IPV served as their own control.
A reflux count is relevant to the stated question because it records how many reflux events occurred during the observation window. Comparing measurements within the same infant can account for stable differences between infants, such as a tendency for one infant to have more events than another. That general advantage does not remove possible changes over time or differences in observation conditions; those need to be addressed by the measurement plan and analysis.
The endpoint description does not define how a reflux event was identified, how counts were recorded, how incomplete observation periods were handled, or how repeated periods were combined for analysis. Most importantly, the registry record does not report the observed mean, standard deviation, or comparison result. The endpoint definition alone cannot establish whether counts differed between the IPV period and the other measurement periods.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry gives a specific primary question but does not post a numerical answer to it. It identifies the outcome as the number of refluxes and describes a comparison of reflux counts during IPV with the mean count during other 20-minute measurement periods. However, no primary endpoint values, effect estimate, uncertainty interval, or test result are reported in the registry record. The direction and size of any difference therefore cannot be determined from this record.
The enrollment of 67 is a study-level enrollment figure, not a reported count of infants contributing complete data to the primary comparison. The record does not state how many participants had evaluable measurements, how many observation periods were available, or whether any participants or measurements were excluded. It would be inappropriate to treat enrollment as the endpoint analysis sample size without a reported analysis population.
The design description is within-patient: infants receiving IPV served as their own controls. A contrast of measurements within infants can be informative, but its interpretation depends on when measurements were made, how repeated counts were summarized, and how differences in observation conditions were handled. The registry record does not explain those details or identify the statistical procedure used. It also does not report whether the observed counts were analyzed as paired data, as repeated observations, or in another way.
The posted safety counts list 67 at risk and zero affected for serious and other adverse events in each of the IPV and Control rows. These figures should be read cautiously because the record describes a single-group, within-patient design and explicitly warns that the arms are not a like-for-like control comparison. The death fields have no reported value. These safety entries do not substitute for the missing reflux endpoint results.
Any sample-size planning illustration is a planning calculation rather than an observed trial finding or an account of the study's original design. The registry describes assumptions including a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect expressed as a fraction of the observed effect. The numerical planning outputs and the numerical observed effect are not reported in the registry record. Those assumptions should not be mistaken for evidence that the study was randomized or that it had a particular probability of detecting an effect.
In short, the record describes the clinical question and measurement approach, but leaves the primary result unreported. It supports no conclusion about the size, direction, or precision of the IPV-associated difference in reflux counts.
9. Statistical Methods Explained
The registry labels the primary outcome as continuous and identifies its summary as a mean with a standard deviation. The endpoint itself is a number of refluxes, so the underlying observation is a count. These descriptions can coexist: counts may be summarized using a mean and standard deviation, even though the possible values of an individual count are discrete. The choice of summary and analysis should reflect how observations are distributed and how they were collected.
What do the mean and standard deviation describe?
In general, a mean describes the average value across observations. A standard deviation describes how dispersed observations are around that average. They answer different questions: the mean concerns the central level, while the standard deviation describes variability among observations. Neither quantity, on its own, shows the uncertainty in a comparison between measurement conditions. The registry record names these summaries but does not report their values for the reflux endpoint.
For a within-patient design, the relevant comparison is ordinarily based on how measurements differ within each patient, rather than treating all measurements in the IPV and non-IPV conditions as unrelated. In general, a paired analysis uses the within-patient differences and their variability. This can account for stable differences between patients. The registry does not state that a paired method was used, nor does it provide the patient-level paired differences or a summary of them.
Why can repeated measurements matter?
The description refers to counts during IPV and measurements every two hours after feeding. If multiple measurement periods were collected from an infant, those observations may be related to one another. In general, measurements from the same person are often not statistically independent. Treating them as independent when they are correlated can make uncertainty estimates misleading. A suitable repeated-measures approach may need to account for within-person dependence, but the exact approach depends on the data structure and prespecified analysis. The record does not state how many observations were obtained per infant or how repeated measurements were incorporated.
Reflux counts may also vary substantially across observation periods. In general, count data can show over-dispersion: variability greater than a simple model assumes. When over-dispersion is present, a model that assumes too little variability can understate uncertainty and make results appear more precise than warranted. This is a general consideration, not a claim about the distribution in this study. The registry reports no distributional assessment, model specification, or analysis result that would show whether over-dispersion was assessed or relevant.
What would an uncertainty interval add?
In general, a confidence interval describes a range of effect estimates compatible with the data under a stated method and its assumptions. It gives information about precision as well as direction and magnitude. A p-value, when reported, addresses compatibility with a specified null hypothesis under the analysis assumptions; it does not describe the size of an effect or its clinical importance. The registry does not report a confidence interval, p-value, or other uncertainty measure for the primary comparison. No precision judgment about that comparison can therefore be made from the record.
The record's planning assumptions mention a two-sided significance level of 0.05 and a normal approximation. These are described as assumptions for planning illustrations based on fractions of an observed effect, with equal allocation between two arms. They are not evidence of the procedure used for the completed study. Nor does a planning calculation show the trial's observed power. The numerical observed effect and the resulting planning figures are not reported in the registry record, and the described two-arm planning setup should not be confused with the single-group, within-patient study design.
What is not specified about the analysis?
The registry record does not report the statistical test or model, whether the comparison was adjusted for any variables, how observations were selected or aggregated, or how the distribution of the outcome was checked. It does not report handling of missing measurements, the number of observations included in the endpoint analysis, or an analysis population. The record lists zero analyses. Accordingly, the endpoint definition and descriptive summary plan are not enough to reconstruct an inferential analysis or reproduce a result.
These distinctions are important when reading a registry entry. A defined outcome is not itself a result; a listed summary statistic is not an observed summary; and a stated planning assumption is not a completed-trial finding. The primary question is clear, but the statistical evidence needed to estimate the difference and its precision is not reported in the registry record.
10. Confidence Intervals for Each Arm
No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.
| Arm | Participants | Mean | Standard deviation | 95% CI for the mean |
|---|---|---|---|---|
| Intrapulmonary Percussive Ventilation | 50 | 0.480 | 0.760 | 0.264 to 0.696 |
| Control | 50 | 0.970 | 0.950 | 0.700 to 1.240 |
R code and output
arm <- c("Intrapulmonary Percussive Ventilation", "Control")
n <- c(50, 50)
m <- c(0.48, 0.97)
sp <- c(0.76, 0.95)
sd <- sp # posted standard deviations
for (i in seq_along(n)) {
se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}
CARM Intrapulmonary Percussive Ventilation 50 0.480 0.760 0.264 0.696
CARM Control 50 0.970 0.950 0.700 1.24011. Multiplicity, Missing Data and Analysis Populations
The registry lists one outcome measure and no analyses. It identifies the number of refluxes as the primary outcome, but does not report an analysis result. The record does not describe a multiplicity adjustment, a hierarchy among outcomes, or a prespecified approach to multiple comparisons. Because the statistical analysis plan is not reported in the registry record, it is not possible to determine whether additional analyses were planned or how their interpretation was intended to relate to the primary outcome.
Missing-data handling is not reported in the registry record. There is no description of how missing reflux counts, incomplete observation periods, or participants without endpoint measurements would be treated. The enrollment figure of 67 does not establish the number included in an endpoint analysis. The record does not provide a participant flow for the primary outcome or explain whether all enrolled participants contributed usable measurements.
The analysis population is also not reported in the registry record. The statement that all patients receiving IPV were their own controls identifies the intended comparison structure, but does not specify who was included in the analysis or how patients with incomplete paired measurements were handled. No analysis method or sensitivity analysis is described. These omissions limit assessment of whether the posted endpoint, if results were available elsewhere, would represent all enrolled participants or a subset.
In general, multiplicity concerns arise when several hypotheses are tested and the chance of a false-positive finding is not addressed. Missing-data decisions can also affect estimates, especially when the amount or pattern of missingness is related to outcomes. Those are general methodological concerns; the registry record does not provide enough information to assess their practical impact in this study.
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 |
|---|---|---|---|
| Intrapulmonary Percussive Ventilation | 0 | 67 | 0.0% |
| Control | 0 | 67 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Intrapulmonary Percussive Ventilation | 0 of 67 |
| Control | 0 of 67 |
The safety record lists two rows, titled Intrapulmonary Percussive Ventilation and Control. Each row reports 67 at risk, zero affected by serious adverse events, and zero affected by other adverse events. The death field has no reported value in either row; a blank value should not be read as a reported count of zero deaths.
These entries require caution. The study is described as a single-group design in which patients receiving IPV were their own controls, and the record specifically warns that the arms are not a like-for-like control comparison. The two rows therefore should not be interpreted as separate randomized groups or as a valid comparative safety analysis. The identical at-risk counts do not establish that there were two distinct sets of participants.
The registry does not report event definitions, the period of safety surveillance, event-level details, or how the group labels were used for safety recording. Zero affected in the posted fields means no events are counted in those fields; it does not establish that all possible harms were assessed or that no unlisted events occurred. The record also does not provide enough detail to evaluate the completeness of safety ascertainment.
13. What the Result Does, and Does Not, Mean
The record describes a study intended to compare the number of refluxes during a 20-minute IPV period with the mean number during other 20-minute periods. It specifies the intended population, the intervention conditions, and a within-patient control approach. Those details clarify what the primary clinical question was.
They do not provide the answer. No observed reflux counts, mean, standard deviation, contrast, confidence interval, or p-value are reported in the registry record. The magnitude and direction of a difference, and the precision with which it might be estimated, are therefore unknown from this entry. It cannot establish whether reflux counts were higher, lower, or similar during IPV relative to the other measurement periods.
Nor does the record permit assessment of whether the endpoint comparison was statistically significant or clinically important. Statistical significance and clinical importance are distinct concepts in general: a result's magnitude and uncertainty matter, not just a test outcome. Here, neither an effect estimate nor an uncertainty measure is reported, so neither can be evaluated.
The single-group design also sets limits on interpretation. The intended comparison is within patients, not between randomized groups. Any observed difference could be interpreted only in the context of the measurement timing, repeated observations, and analysis methods. Those details are not sufficiently reported to assess the potential influence of time or other changing conditions. The record's safety fields similarly should not be treated as a comparison between independent groups.
The enrollment of 67 and completed status establish enrollment and registry status, not a demonstrated endpoint result. The planning assumptions are not trial findings, and planning illustrations are not observed power. Overall, the entry documents a research question and a measurement framework, while leaving the principal numerical evidence unavailable in the registry record.
14. Why This Trial Matters Statistically
This study is statistically interesting because its stated comparison is within infants rather than between separate randomized groups. That structure makes the pairing of measurements central. A reader needs to know how the reflux counts were paired, how multiple observation periods were summarized, and whether repeated measures from the same infant were accounted for. The record describes the self-control idea but does not provide the analysis details needed to evaluate those choices.
The outcome is a count, while the registry identifies its summary as a mean and standard deviation. This highlights a general issue in clinical data analysis: a familiar summary can be useful, but the analysis must also reflect the outcome's distribution and collection structure. Counts may have skew or greater variability than a simple model assumes; those are possibilities to assess, not details established about this study. No distributional diagnostics or model details are reported.
The record also illustrates why study design, analysis, and reporting should be read separately. It identifies a completed study with enrollment of 67, but does not report the endpoint estimates or analysis population. It includes planning assumptions for a two-arm illustration, while the clinical design is described as single-group and within-patient. A planning scenario cannot replace an observed estimate or serve as evidence about the completed analysis.
Finally, the safety labels could invite a mistaken between-group interpretation. The registry warns that the arms are not a like-for-like control comparison, and the design description identifies participants as their own controls. Recognizing that distinction prevents the group labels from being read as evidence of a randomized safety contrast. The record is useful for identifying the question and design, while its missing results and methods leave important statistical questions unresolved.
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 main limitation is that the registry record does not report the primary endpoint results. It provides no reflux-count means, standard deviations, effect estimate, or uncertainty measure. As a result, the central comparison cannot be quantified or interpreted for direction, magnitude, or precision.
The within-patient design is described, but important operational details are absent. The record does not specify how the primary measurement periods were selected, how many periods were collected per infant, how individual periods were combined, or whether the timing of IPV and comparison measurements was standardized beyond the statements about feeding and measurement intervals. Such details matter when comparing observations that may vary over time.
The record also does not report the analysis method, distributional assumptions, handling of repeated observations, or the number of participants with evaluable data. Missing-data procedures and the analysis population are not reported in the registry record. Enrollment therefore cannot be assumed to equal the endpoint analysis sample.
The registry identifies a single-group model, allocation as NA, and masking as none. It explicitly cautions that the listed arms are not a like-for-like control comparison. Consequently, the safety rows should not be interpreted as independent treatment and control groups. The death fields have no reported value, and the record does not describe the duration or completeness of safety monitoring.
Finally, the planning assumptions describe a two-arm calculation based on a fraction of the observed effect, but the numerical observed effect and planning outputs are not reported in the registry record. This illustration does not explain the original design justification and should not be treated as observed power. These limitations reflect missing registry detail; they do not establish what was or was not done outside the information recorded.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Influence of IPV on GOR in Infants From 0 to 12 Months. — NCT02124863.
- Registry record last updated 2017-02-10; status last verified 2016-12.
- Results first posted 2015-03-17.
- 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.
19. Record Summary
NCT02124863 is a completed, single-group study of IPV and gastro-oesophageal reflux in infants from 0 to 12 months. Enrollment was 67. The record describes reflux counts during 20 minutes of IPV compared with mean counts during other 20-minute periods, with each patient serving as their own control.
The primary outcome is the number of refluxes, summarized by mean and standard deviation. The IPV description specifies a rate of 300/min and p = 10cmH2O, at least 120 min after feeding. Numerical endpoint results and the statistical analysis are not reported in the registry record. Safety rows list zero serious and other adverse events affected in both labeled groups; death counts are not reported. The record cautions that the arms are not a like-for-like control comparison.