Comparison Between Gastric and Post Pyloric Tube Feedings in Children With Bronchiolitis Requiring High Flow Nasal Cannula: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Comparison Between Gastric and Post Pyloric Tube Feedings in Children With Bronchiolitis Requiring High Flow Nasal Cannula (NCT03346850), a randomized na study. The primary outcome is Length of Respiratory Supprt.

2. Clinical Question

The comparison concerns two ways of providing enteral nutrition during hospital care. The primary endpoint is respiratory-support duration, not a direct measure of feeding adequacy or a broad measure of recovery. The registry also lists secondary outcomes involving emesis, peak respiratory support, chest X-rays, emergency-room revisits, and hospital readmission. These outcomes address other aspects of the hospital course and follow-up, but they do not change the primary question.

The registry describes the study as randomized, single-masked, and parallel-group. It records 40 enrolled participants, with 20 in each group for the primary outcome. The clinical question is therefore a between-group comparison of average duration in this enrolled sample. The registry does not report further details about who was masked or the eligibility criteria used to select participants.

3. Trial Design

The registry record describes a randomized, single-masked, parallel-group study comparing NGT feeding with NDT feeding. The two groups are listed as separate arms, and participants were assigned to one of the two feeding approaches. The record reports 40 enrolled participants. For the primary outcome, each arm has results for 20 participants.

The study focused on children hospitalized with bronchiolitis who required high flow nasal cannula therapy. Its stated purpose was to compare the two tube-feeding approaches in this clinical setting. The trial is listed as phase NA, and its status is terminated. The registry records a start date of 2018-12-01 and a primary completion date of 2019-04-01. It does not report why the study was terminated, so the status alone does not establish the reason or its implications for the results.

Single masking means that the registry identifies the study as masked in one respect, but it does not identify who was masked. Details such as whether participants, caregivers, outcome assessors, or analysts were masked are not reported in the registry record. The arm descriptions are also blank, so additional procedures within each feeding group cannot be described from this record.

The registry lists a primary outcome of length of respiratory support, in hours, measured from hospital admission to discharge; its stated timeframe is about 6 days. The outcome is summarized as a mean with standard deviation. Secondary outcomes include measures of emesis, peak respiratory support, chest X-rays, emergency-room revisits, and readmission. The registry lists 8 outcome measures in total and reports results for 3 secondary outcomes. Further information about the intended analysis populations, follow-up procedures, sample-size justification, or original statistical plan is not reported in the registry 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.

Overall Study

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.

6. Primary Endpoint

The registry lists the primary outcome as Length of Respiratory Supprt, measured over from the time of hospital admission to discharge (about 6 days).

The primary endpoint is length of respiratory support, measured in hours from hospital admission to discharge. It describes the duration of respiratory support over the hospitalization and is summarized as a mean and standard deviation for each feeding group. The registry gives the timeframe as about 6 days.

Comparing this endpoint between the randomized groups addresses whether the average recorded duration differed between children assigned to NGT feeding and those assigned to NDT feeding. A duration measure is useful for describing the course of care across the admission, but it is not a measure of every aspect of a child's condition. It does not, by itself, describe the intensity of support at each moment, why support ended, or outcomes after discharge.

In general, a mean is the arithmetic average of observed values. A standard deviation describes how spread out individual observations are around that average; it is not the uncertainty around the mean itself. The registry reports mean respiratory-support durations of 107.0 hours for NGT feeding and 128.0 hours for NDT feeding, with standard deviations of 49.0 and 119.0 hours, respectively. Those summaries describe the recorded primary outcome in the two groups. They do not establish that the observed difference is precise or attributable to the assigned feeding approach; those questions depend on the uncertainty around the between-group estimate and the study design.

7. Results Posted in the Registry

• Nasoduodenal Tube (NDT) Feeding: mean 128.00 versus 107.00 on control; difference 21.00 (95% CI -35.40 to 77.40), standardized effect d = 0.23; z-test p = 0.466.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Number of Participants With Emesis

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Nasoduodenal Tube (NDT) Feeding: 5.0% (1/20) versus 30.0% (6/20) on control; risk difference -25.0 percentage points (95% CI -47.2 to -2.8), risk ratio 0.17 (0.02–1.26); unadjusted two-proportion z-test p = 0.037.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the proportion with the event is statistically lower for Nasoduodenal Tube (NDT) Feeding than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Peak Respiratory Support in Liters Per Minute

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Nasoduodenal Tube (NDT) Feeding: mean 7.80 versus 8.00 on control; difference -0.20 (95% CI -1.43 to 1.03), standardized effect d = -0.10; z-test p = 0.750.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Nasoduodenal Tube (NDT) Feeding and the control. The interval gives the range of effects that remain compatible with the data.

Number of Participants Who Revisited the Emergency Room (ER)

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Nasoduodenal Tube (NDT) Feeding: 5.9% (1/17) versus 5.6% (1/18) on control; risk difference 0.3 percentage points (95% CI -15.1 to 15.7), risk ratio 1.06 (0.07–15.62); unadjusted two-proportion z-test p = 0.967.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Nasoduodenal Tube (NDT) Feeding and the control. The interval gives the range of effects that remain compatible with the data.

The registry lists secondary outcomes spanning feeding-related symptoms, respiratory support, imaging, and events after discharge. The posted results cover emesis, peak respiratory support, and emergency-room revisits; results for the other listed secondary outcomes are not reported in the registry record. This means that the secondary evidence is incomplete relative to the full list of intended outcomes.

Across the posted secondary outcomes, the pattern is not uniform. The emesis comparison points in a different direction from the close group means for peak respiratory support, while the emergency-room revisit counts are the same despite different denominators. This mixture does not form a consistent pattern that independently resolves the primary question about duration of respiratory support. These outcomes measure different aspects of care and follow-up, so agreement or disagreement among them should not be expected to function as a single combined endpoint.

The primary result concerns average respiratory-support duration, whereas secondary outcomes provide complementary descriptions of symptoms, support intensity, and subsequent service use. A secondary outcome can add context, but it does not replace the primary endpoint or establish the effect on that endpoint. In particular, an observed difference on one secondary measure does not show that the primary outcome changed in the same way.

Unadjusted secondary results carry less weight as confirmatory evidence when several outcomes are examined. In general, testing many outcomes increases the possibility that at least one result will appear unusual by chance. The registry record does not report a multiplicity adjustment, a hierarchy of secondary hypotheses, or a designation of which secondary outcomes were confirmatory. The reported secondary p-values should therefore be viewed as descriptive or exploratory evidence, not interpreted as though each were the sole planned test.

The registry lists 7 secondary outcome entries, including repeated entries for emergency-room revisits and readmission, while the posted secondary results include 3 outcome records. The registry does not explain the relationship between the full outcome list and the smaller set of posted results. This reporting gap limits the ability to assess the secondary findings as a complete set or to understand whether unreported outcomes were not measured, not analyzed, or simply not posted.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Number of Participants With Emesis
• Peak Respiratory Support in Liters Per Minute
• Number of Chest X-rays Obtained Among All Participants
• Number of Participants Who Revisited the Emergency Room (ER)
• Number of Participants Who Revisited the Emergency Room (ER)
• Number of Participants Who Were Readmitted to the Hospital
• Number of Participants Who Were Readmitted to the Hospital

9. Statistical Interpretation

10. Statistical Methods Explained

The registry presents continuous outcomes as group means and standard deviations, and binary outcomes as participant counts. For the primary endpoint, the contrast is a mean difference between NDT and NGT. For binary outcomes, the posted comparisons use risk differences. The interpretation of these statistics depends on the outcome type and on the uncertainty around the estimate.

What does the mean difference represent?

In general, a mean difference subtracts the average in one group from the average in the other. The primary comparison is defined as NDT minus NGT. A positive estimate therefore means the observed mean is higher in the NDT group; a negative estimate means it is lower. The posted estimate is 21.0 hours. The calculation uses the group summaries, and the comparison is unadjusted: the registry does not report a model that adjusts for participant characteristics or other covariates.

A standard deviation describes variation among individual observations within a group. It is distinct from a standard error, which describes the sampling uncertainty of an estimate. The posted primary standard deviations are 49.0 hours for NGT and 119.0 hours for NDT. The notably different spreads matter because substantial variation makes the group means less precise, especially when each arm has 20 participants. The registry does not report distributional plots or participant-level values that would permit a closer assessment of skew, outliers, or other features of the outcome distribution.

How should the confidence interval be read?

In general, a confidence interval expresses uncertainty around an estimated effect. It gives a range of values compatible with the data and the method used to construct the interval. The primary interval, -35.4 to 77.4 hours, includes zero, the value corresponding to no mean difference. This means the posted estimate is compatible with a range of effects in both directions. It does not mean that every value in the interval is equally likely, nor does it prove that the true effect is zero.

What does the p-value add?

In general, a p-value measures how unusual data at least as incompatible with a specified null hypothesis would be if that hypothesis and the statistical model were correct. It is not the probability that the null hypothesis is true, and it does not measure the size or clinical importance of an effect. The primary unadjusted p-value is 0.466. It should be considered with the estimated mean difference and its interval, not as a stand-alone verdict. The registry does not report a prespecified statistical testing plan, so details such as the originally intended test and any planned adjustments are not reported in the registry record.

Why distinguish binary and continuous outcomes?

In general, a continuous outcome can take values across a measurement scale, such as hours, and may be summarized by a mean. A binary outcome records whether an event occurred for each participant, and is by counts and denominators. A risk difference is the difference between the proportions of participants with the event in the two groups. A negative risk difference means the observed proportion is lower in NDT than in NGT, when the contrast is NDT minus NGT. The registry also posts relative measures for some binary outcomes, but the risk difference offers an absolute comparison in the outcome's probability scale.

For emesis, the posted counts are 6 of 20 in the NGT group and 1 of 20 in the NDT group. The estimated risk difference is -0.25, with a 95% confidence interval from -0.472 to -0.028 and an unadjusted p-value of 0.037. Those are unadjusted results for a secondary outcome. The registry does not report whether the analysis accounted for repeated events, baseline characteristics, or other features beyond the participant counts.

What does unadjusted mean in this record?

In general, an unadjusted comparison uses the reported group summaries without controlling statistically for other variables. Random assignment is intended to support a fair comparison, but it does not guarantee that all participant characteristics will be balanced in a small sample. The record does not report baseline characteristics or adjusted analyses, so the extent to which any observed imbalance could affect the estimates cannot be assessed from the posted results.

The record lists no reported analyses for the secondary outcomes. The displayed comparisons are therefore not accompanied by registry-reported model details, analysis populations, or adjustment procedures. The registry's sample-size planning illustration uses a two-sided significance level of 0.05, equal allocation, and a normal approximation; these are planning assumptions for the illustration, not evidence of the original trial's design. The original sample-size justification and analysis plan are not reported in the registry record.

General statistical caution applies when many outcomes are assessed. Each additional test creates another opportunity for a chance finding, and unadjusted p-values do not account for that multiplicity. The record lists several secondary outcomes but does not report a correction strategy or designate a confirmatory secondary endpoint. Accordingly, secondary results can describe patterns in the observed data, but should not be treated as if a single prespecified test had been conducted.

11. Confidence Intervals and Precision

The primary mean difference is 21.0 hours, with a 95% confidence interval from -35.4 to 77.4 hours. The interval is broad relative to the point estimate and includes zero. It therefore leaves considerable uncertainty about both the direction and size of the difference in average respiratory-support duration. The results are compatible with a shorter mean duration in the NDT group as well as a longer mean duration.

In general, a confidence interval reflects both the observed data and the statistical method used to estimate uncertainty. It should not be read as a range containing every individual participant's duration; it concerns the group-level effect estimate. Nor does a confidence interval that includes zero prove no difference. To support a claim of equivalence or non-inferiority, a study would need a prespecified margin and an analysis designed for that question. Such a margin and analysis are not reported in the registry record.

The primary outcome has 20 participants in each group, and the reported standard deviations are 49.0 hours for NGT and 119.0 hours for NDT. The larger spread in the NDT group is consistent with substantial variation in observed duration in that arm. With limited participant numbers and variable observations, the mean difference can be imprecise. The record does not provide raw values, subgroup estimates, or sensitivity analyses that might clarify whether the spread reflects a small number of unusually long or short durations.

Precision also varies by secondary outcome. Some posted intervals are wide, reflecting that the data do not tightly identify the corresponding group difference. The emergency-room revisit comparison, for example, is based on denominators of 18 and 17, rather than 20 in each group. The registry does not explain these denominators or report how unavailable outcome information was handled. Differences in available follow-up can limit precision and complicate interpretation.

In general, an estimate and its interval are more informative together than a p-value alone. Here, the primary interval conveys that a range of effects remains plausible under the reported analysis. The available results should consequently be read as uncertain estimates, not as precise evidence that the groups are identical or that one approach changes the outcome by a particular amount.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The planning figures are illustrations based on the observed effect, not the trial's original design justification. For the continuous primary outcome and the other non-time-to-event outcomes, the figures are participants per arm. They are not total sample sizes. The registry's planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is set to the stated fraction of the observed effect. The original trial's own sample-size assumptions are not reported in the registry record.

The 80% power column describes the number of participants per arm estimated to give an 80% chance of detecting the selected effect under those planning assumptions, if the effect and model assumptions used for the calculation were correct. The 90% power column uses a higher target chance of detection and therefore generally calls for more participants per arm. These are prospective planning quantities, not summaries of what happened in the trial.

The rows for 100%, 75%, and 50% of the observed effect illustrate how the required sample size changes when the target effect is made smaller. Detecting a smaller effect generally requires more participants, because a smaller difference is harder to distinguish from random variation. For the primary outcome, the planning figures range from 295 participants per arm for 80% power when using 100% of the observed effect to 1,180 participants per arm for 80% power when using 50% of the observed effect. The corresponding 90% figures are 395 and 1,579 participants per arm.

These calculations use the observed effect as their starting point, so they inherit uncertainty from the small study. They do not establish that the observed effect is the true effect or that a future study would achieve the stated power. This is not observed power. The record also states that time-to-event calculations, if present, would report total events rather than participants per arm; the posted outcomes are not time-to-event outcomes.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = 21.000; pooled standard deviation σ = 91.000.
2. n = 2 × (1.96 + 0.842)² × 91.000² / 21.000² = 294.8, rounded up to 295 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- 21                      # observed difference in means
sigma <- 91                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(3346850)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 295 (80% power), 395 (90% power)
 75% of observed effect: n per arm = 525 (80% power), 702 (90% power)
 50% of observed effect: n per arm = 1,180 (80% power), 1,579 (90% power)
power.t.test: 295.7 
Simulated power at n = 295 per arm: 0.797 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Multiplicity, Missing Data and Analysis Populations

The registry record lists multiple secondary outcomes, but does not report a multiplicity strategy. It does not state whether one secondary outcome was designated as confirmatory, whether a hierarchy of tests was planned, or whether p-values were to be adjusted for examining several outcomes. In general, multiplicity matters because repeated testing can increase the chance of at least one apparently notable result even when there is no underlying difference. An unadjusted secondary p-value should therefore not be interpreted as having the same evidential status as a single prespecified primary test.

The registry lists 7 secondary outcome entries and reports results for 3 secondary outcomes. Results for the other listed outcomes are not reported in the registry record. The record does not say why results are unavailable, whether those outcomes were measured, or whether their absence reflects analysis or reporting decisions. This prevents a complete assessment of the planned secondary outcome set.

Some outcome denominators are smaller than the primary outcome group sizes. The emergency-room revisit results use 18 participants in the NGT group and 17 in the NDT group. The registry does not explain the difference between these denominators and the 20 participants per arm reported for the primary outcome. It also does not report how missing or unavailable follow-up data were handled, whether any imputation was used, or whether analyses followed an intention-to-treat or other population definition.

The primary result is reported for 20 participants in each arm, but the registry does not describe exclusions, withdrawals, protocol deviations, or the analysis population in detail. Further information about missing outcome data, the number of participants assessed at each time point, and reasons for non-availability is not reported in the registry record. These omissions matter because missingness can affect an estimate if the availability of an outcome is related to the outcome itself or to group assignment.

The registry does not report a detailed statistical analysis plan, interim analyses, a stopping rule, or the original sample-size justification. It also does not explain why the study is listed as terminated. Without this information, it is not possible to assess whether analyses or reporting followed a prespecified plan, or whether the listed outcomes and comparisons represent all planned analyses.

15. 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.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: pneumothorax (5.0%).

The registry records serious adverse events for 0 of 20 participants in the NGT group and 1 of 20 participants in the NDT group. It records other adverse events for 1 of 20 participants in the NGT group and 0 of 20 participants in the NDT group. No deaths are recorded in either group. The registry also lists pneumothorax at 5.0% among the serious adverse event terms.

These counts are descriptive of the adverse-event reporting in the registry. With 20 participants in each group, the number of recorded events is small, and the record does not provide enough detail to characterize event severity, timing, duration, or attribution beyond the listed category and term. It does not state whether the listed serious event term refers to the single serious adverse event in the NDT group, so that relationship should not be assumed from the posted summary alone.

In general, adverse-event counts in a small study cannot precisely establish whether event risks differ between groups. The absence of a recorded event in one group is not proof that the event cannot occur. The registry's safety entries should be read as reported observations, not as a complete estimate of safety or as evidence for a treatment recommendation.

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

The primary result is an estimate of the difference in mean respiratory-support duration between children assigned to NDT feeding and those assigned to NGT feeding. In the observed sample, the NDT mean was higher. The confidence interval is broad and includes values on both sides of zero, so the record does not precisely establish the direction or size of the underlying group difference.

This result does not show that the two feeding approaches are equivalent. A nonsignificant p-value does not demonstrate that there is no meaningful difference, and the registry does not report a prespecified equivalence margin or a non-inferiority analysis. Conversely, the point estimate alone does not establish that NDT feeding causes a longer duration. The study is randomized, but the small reported group sizes and uncertainty around the estimate limit how firmly the observed difference can be interpreted.

The record provides a focused comparison in children hospitalized with bronchiolitis requiring high flow nasal cannula. It does not establish effects in populations outside that setting. Eligibility details, baseline characteristics, and subgroup analyses are not reported in the registry record, so the extent to which the enrolled participants represent other children or care settings cannot be assessed from the posted results.

The secondary outcomes add context but do not settle the primary question. One secondary comparison has an unadjusted result that merits cautious attention, while other posted measures do not show a uniform pattern. Multiple secondary outcomes are listed, and the registry does not report a multiplicity plan. These findings should not be treated as definitive on their own.

The registry reports a terminated study and does not give a reason for termination. It also does not report the original sample-size assumptions, a detailed analysis plan, or how missing data were handled. As a result, the posted evidence is best understood as a limited estimate from the participants and outcomes reported, with important uncertainty about precision, completeness, and the original design context. No conclusion about clinical choice follows from the statistical results alone.

17. Why This Trial Matters Statistically

This study illustrates a common challenge in clinical research: a randomized comparison can produce a clear numerical estimate while still leaving substantial uncertainty about what the data imply. The primary point estimate is expressed in the natural unit of the endpoint, hours of respiratory support, which makes its direction understandable. Its confidence interval is essential for judging how much uncertainty remains around that estimate.

The contrast between the observed group means and the uncertainty interval is especially instructive. A point estimate alone can draw attention to one direction, but the interval includes both shorter and longer average durations for NDT relative to NGT. The registry therefore supports describing the sample difference, while not supporting a precise conclusion about the underlying effect. This is a useful distinction between estimating an effect and deciding whether the estimate is sufficiently precise for a stronger claim.

The reported standard deviations also matter. The groups have notably different observed variability, and the NDT group has the larger spread. A mean can conceal variation among individuals, especially when observations are dispersed. Readers should not treat the group average as a typical individual outcome or assume that all participants experienced a similar course.

The record also demonstrates why secondary outcomes need context. They cover several clinically distinct domains, but only some have posted results, and no multiplicity procedure is reported. A result that appears notable in one secondary comparison does not automatically outweigh the uncertain primary estimate. Complete reporting and a prespecified approach to multiple outcomes are important for distinguishing confirmatory evidence from exploratory patterns.

Finally, the study is listed as terminated, yet the reason is not reported in the registry record. The status is relevant context, but it cannot be used to infer why enrollment or follow-up ended. Interpreting a trial statistically requires both the numerical results and enough information about its design, analysis, and reporting to understand how those results arose. This record offers useful outcome estimates while leaving several of those contextual questions open.

18. 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 comparison is based on 20 participants per arm, and the confidence interval is wide. The estimate therefore has limited precision. The registry does not provide participant-level data, distributional summaries beyond means and standard deviations, or sensitivity analyses. The greater spread in the NDT group may influence the stability of its mean, but the posted summaries do not reveal how the individual observations are distributed.

The registry lists the study as terminated without stating why. It reports 40 enrolled participants but does not report the original target enrollment or whether the trial met its intended recruitment goal. The reason for termination, the timing of any decision to stop, and any consequences for follow-up or analysis are not reported in the registry record. No inference about the cause of termination can be made from status alone.

There is limited detail about the trial procedures. Although the design is described as single-masked, the identity of the masked group is not reported. Arm descriptions are blank, and further information about eligibility criteria, baseline characteristics, protocol adherence, and feeding procedures is not reported in the registry record. These omissions make it difficult to assess the practical context of the comparison or the possibility of imbalances in a small randomized sample.

Secondary reporting is incomplete: the registry lists 7 secondary outcome entries, while results are posted for 3. The emergency-room revisit results have smaller denominators than the primary outcome groups, and the record does not explain why. Missing-data methods, analysis populations, and the treatment of withdrawals or protocol deviations are not reported. These gaps make it difficult to determine how complete the outcome data are and whether the analyses included all randomized participants.

The registry does not report the original sample-size justification, a detailed statistical analysis plan, multiplicity handling, or interim-analysis procedures. The sample-size figures are planning illustrations based on the observed effects, not information about the trial's own design. Together, these limitations constrain interpretation of both the primary estimate and the secondary findings.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Comparison Between Gastric and Post Pyloric Tube Feedings in Children With Bronchiolitis Requiring High Flow Nasal Cannula — NCT03346850.
• Registry record last updated 2020-03-25; status last verified 2020-03.
• Results first posted 2020-03-25.
• 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.

22. Record Summary

The registry describes a randomized, single-masked, parallel-group study of NGT versus NDT feeding in children hospitalized with bronchiolitis requiring high flow nasal cannula. It records 40 enrolled participants and a primary outcome of length of respiratory support in hours, from admission to discharge.

The primary outcome is reported for 20 participants per arm. The estimated mean difference, NDT minus NGT, is 21.0 hours, with a 95% confidence interval from -35.4 to 77.4 hours and an unadjusted p-value of 0.466. The interval is compatible with effects in either direction and indicates substantial uncertainty.

The registry lists 7 secondary outcome entries and posts results for 3 secondary outcomes. It also records serious and other adverse events and no deaths in either group. The study status is terminated, but the reason is not reported in the registry record. Original design assumptions, a detailed analysis plan, and missing-data procedures are also not reported.