Improving Lactation Success in Black Mothers of Critically Ill Infants: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Improving Lactation Success in Black Mothers of Critically Ill Infants (NCT05147987), a randomized na study. The primary outcome is Number of Participants Acceptance of the Intervention.

2. Clinical Question

The clinical question is motivated by the registry's account of racial disparities in breast-milk provision to infants in the NICU and the practical challenges Black mothers may face in pumping frequently. The study tests a device-and-app approach intended to make pumping more discreet and convenient while tracking pumping activity and milk production. The registry also lists pumped milk volume, days to secretory activation, total pumping sessions, and lactation duration as secondary outcomes.

The primary endpoint is specifically acceptance among participants offered the intervention. The standard care group did not receive the intervention, so its recorded zero does not represent a comparable acceptance measurement. The primary result therefore addresses whether the intervention was accepted among those offered it, rather than whether the device improved a clinical outcome or outperformed standard care.

3. Trial Design

The registry describes a completed, randomized, single-masked, parallel-group study sponsored by the University of Florida. Its recorded enrollment is 32. The registry lists the study start as 2022-01-01 and primary completion as 2025-02-15. The phase is recorded as NA. The brief summary describes randomizing 40 Black mothers, while the enrollment field records 32; the reason for this difference is not reported in the registry record.

Participants were assigned to an intervention group or a standard care group. The intervention group was provided a discreet, hands-free wearable breast pump with an associated app. The standard care group was provided a standard mechanical breast pump without an associated app. The model is parallel, so the two groups are separate trial arms rather than repeated conditions for the same participant. The registry calls the masking single but does not report who was masked or how masking was implemented.

The primary outcome is a count of participants accepting the intervention, assessed by survey questions at 20-22 days. The registry describes the standard care group as not receiving the intervention, which limits the primary outcome to the intervention group. Secondary outcomes include pumped milk volume, days to secretory activation, total pumping sessions, and lactation duration. The posted numerical secondary results cover the first three; numerical results for lactation duration are not reported in the registry record.

The study's stated purpose is a pilot assessment of feasibility and potential benefits, including whether results offer a signal of effectiveness to inform a subsequent adequately powered randomized clinical trial. That purpose is important when interpreting small-group estimates: the posted results are exploratory and do not establish a definitive treatment effect. The protocol's planned sample size, its justification, and the intended statistical analysis plan are 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

Analysis population for the primary outcome, as defined in the registry: The standard care group did not receive the intervention

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 Number of Participants Acceptance of the Intervention, measured over at 20-22 days.

The primary endpoint is the number of participants accepting the intervention, measured by survey questions at 20-22 days. It is a count outcome focused on acceptance among participants offered the wearable pump and associated app. The registry reports 16 participants for the intervention group and zero for standard care. Because the standard care group did not receive the intervention, its zero is not a measure of rejection or non-acceptance, and the registry does not provide a meaningful between-group comparison for this endpoint.

Acceptance is relevant to a feasibility-focused pilot: an intervention that participants do not accept may be difficult to evaluate in a later trial. The registry's stated objectives also include evaluating the feasibility of the device and app and assessing whether results provide a signal to support a subsequent randomized trial. The endpoint therefore offers information about uptake, but it does not by itself measure pumping frequency, milk production, infant outcomes, or the comparative effect of the intervention on lactation.

The registry does not report a confidence interval, hypothesis test, or analysis population for the acceptance count. It also does not give survey response details or a separate definition of what counted as acceptance. Those details are not reported in the registry record, so the count should be interpreted narrowly as the posted result for this feasibility measure.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What do the group means describe? For the continuous secondary outcomes, the registry reports a mean and standard deviation for each group. A mean is the average observed value in the group; the standard deviation describes the spread of individual observations around that average. These summaries do not show the full distribution, and two groups can have similar means while differing in variability or in the shape of their distributions. The reported standard deviations are substantial relative to the group means for some outcomes, reinforcing the importance of reading the averages alongside uncertainty.

What does a mean difference represent? The posted mean difference compares the intervention-group average with the standard care average. A positive value means the intervention-group mean is numerically higher for the outcome as coded. It is a difference in group averages, not a difference for each participant, and it does not by itself account for other factors. The registry's comparisons are unadjusted; covariate-adjusted estimates are not reported in the registry record.

How should confidence intervals be read? A confidence interval describes uncertainty around an estimated group difference under the assumptions of the method used. A narrow interval indicates greater precision than a wide interval. When the interval includes zero, the data are compatible with no mean difference as well as with differences in either direction within the interval. This does not prove that the groups are identical. When an interval lies on one side of zero, the estimate is still uncertain, and the interval's width matters for judging the range of values compatible with the data. These are general statistical interpretations; they do not establish clinical importance.

The reported p-values for the continuous comparisons are unadjusted. A p-value measures how unusual the observed data, or more extreme data, would be under a specified null model and its assumptions. It is not the probability that the null hypothesis is true, and it does not measure the size or practical importance of an effect. The registry does not list reported analyses, so the posted unadjusted comparisons should not be mistaken for sponsor-reported hypothesis tests.

Why does variability matter? Standard deviations describe observed spread, while standard errors describe uncertainty in an estimated mean. Greater variability generally makes group differences harder to estimate precisely when other features are held fixed. The posted group summaries show substantial spread for pumped milk volume and total pumping sessions. General statistical methods may also need to account for over-dispersion when count outcomes vary more than a simple count model expects. The registry does not report a count-model analysis, an over-dispersion assessment, or an analysis method for the primary acceptance count; no such method should be inferred.

What are the planning illustrations? The planning figures are illustrations based on stated fractions of observed effects, a two-sided significance level of 0.05, equal allocation, and a normal approximation. They express participants per arm for 80% or 90% power under those assumptions. They are not the study's planned enrollment, observed power, or evidence that a future trial will obtain the assumed effect. Because the estimates come from a pilot, they may be unstable; planning on a fraction of the observed effect is an assumption, not a forecast. The registry does not report the trial's own sample-size justification.

For continuous outcomes, the planning illustrations are based on the observed mean differences and pooled variability described in the posted summaries. The planning values should be interpreted as conditional calculations: changing the effect assumed, variability, allocation, or analysis method changes the planning requirement. They do not account for details not reported in the registry record, such as attrition assumptions or covariate adjustment. No time-to-event planning result is relevant to the posted outcomes.

What can be concluded from the statistical record? The registry provides arm-level summaries and calculated unadjusted comparisons for three continuous secondary outcomes, but no reported analysis set, adjustment method, or multiplicity procedure. The reported intervals and p-values are therefore useful descriptive inferential summaries, not a complete analysis plan. General statistical practice distinguishes exploratory pilot signals from confirmatory evidence: estimates can inform a later study's design, while uncertainty and analytic choices need to be addressed in that study. Details of randomization implementation, allocation concealment, missing-data handling, and the identity of those masked are not reported in the registry record.

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.

R code and output

arm    <- c("Intervention Group")
n      <- c(16)
events <- c(16)
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 Group  16  16  100.0  79.4  100.0  80.6  100.0  80.5  99.9

11. Multiplicity, Missing Data and Analysis Populations

The registry does not report a statistical analysis plan, a multiplicity strategy, or a hierarchy for interpreting the secondary outcomes. The posted comparisons for pumped milk volume, days to secretory activation, and total pumping sessions are unadjusted. When several outcomes are examined, the chance of observing at least one apparently notable result by chance can increase. This general concern is relevant to the unadjusted p-value for total pumping sessions; without a reported plan, its confirmatory status is not established.

Missing-data handling is not reported in the registry record. The available group summaries list 16 participants for the intervention group and 15 for standard care for the continuous outcomes, but the record does not explain whether those values represent all randomized participants, outcome-specific available cases, or another analysis population. It does not report reasons for missing observations, imputation, or sensitivity analyses. The primary endpoint lists 16 intervention participants and zero for standard care, with the latter described as not receiving the intervention; that zero should not be interpreted as missingness or as non-acceptance.

The registry does not identify an intention-to-treat, per-protocol, or other analysis population, and it does not report how participants were handled if they did not follow their assigned approach. The masking designation is single, but the identity of the masked parties is not reported. Interim analyses and stopping rules are also not reported in the registry record. These omissions limit assessment of how the posted estimates were generated and how robust they are to analytic choices.

Without these details, readers cannot determine whether the statistical tests were prespecified, how all outcomes were handled, or whether missingness could have influenced the group summaries. This does not show that the analyses were inappropriate; it means the registry record does not provide the information needed to assess those issues. The results should therefore be interpreted as posted summaries and unadjusted comparisons rather than as a fully documented confirmatory analysis.

12. 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 5% reporting threshold.

The registry reports zero serious adverse events and zero deaths among the intervention group, with 16 at risk for serious adverse events and 16 at risk for other adverse events. For the standard care group, it reports zero serious adverse events and zero deaths, with 15 at risk for serious adverse events and 15 at risk for other adverse events. No top serious adverse-event terms are listed.

These figures describe the events recorded during the study and the group sizes used in the safety record. Zero recorded events does not prove that an event is impossible or that the approaches have identical safety profiles. A pilot study with limited group sizes can provide only limited information about uncommon events, and the registry does not report the observation duration or additional detail about adverse-event ascertainment. The figures should be read as a record of what was reported, not as a comprehensive safety comparison or a basis for medical advice.

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

The results describe a small randomized pilot study of a wearable breast pump with an associated app compared with a standard mechanical breast pump without an app. The primary measure records acceptance among participants offered the intervention. The secondary summaries describe group averages for milk volume, days to secretory activation, and pumping sessions. These observations can inform feasibility and help frame questions for further study, consistent with the registry's stated pilot objectives.

The posted results do not establish whether the intervention improves lactation outcomes. The primary endpoint is not a between-group comparison, and the unadjusted secondary findings are exploratory. The total pumping sessions estimate is a signal in the posted data, but one secondary result cannot resolve the overall clinical question, particularly without a reported multiplicity plan. The other continuous estimates are uncertain, as reflected by their confidence intervals.

Statistical uncertainty is not the same as proof of no difference. Confidence intervals that include zero indicate that the summaries are compatible with a range of possible group differences, including no difference; they do not demonstrate equivalence. Likewise, an interval excluding zero does not by itself establish clinical importance, reproducibility, or a causal explanation. The registry does not report a threshold for a clinically meaningful difference.

The registry record also leaves important interpretive details unspecified, including the analysis populations, missing-data methods, and the full statistical plan. The brief summary describes a plan to randomize 40 mothers, while recorded enrollment is 32; the reason is not reported in the registry record. Together, these limits mean the findings should be treated as pilot evidence and not as a definitive estimate of effectiveness. No conclusion about an individual mother's care follows from these group-level results.

14. Why This Trial Matters Statistically

This study matters statistically because it illustrates the difference between feasibility outcomes and comparative effectiveness outcomes. Acceptance of the intervention is relevant to whether a later study may be practical, but it is not itself evidence that the device changes milk production or other lactation outcomes. Keeping those questions separate avoids treating a feasibility count as a treatment-effect estimate.

The trial also demonstrates why estimates and their uncertainty should be read together. Group means alone can make an apparent difference seem more decisive than the data warrant. Confidence intervals communicate how imprecisely a pilot estimates group differences, while unadjusted p-values provide only a limited view of the evidence and do not convey effect size or clinical importance.

With several secondary outcomes, an apparently notable result can arise even when no outcome has a true effect. The registry does not report how multiplicity was handled, so the total pumping sessions finding is appropriately viewed as exploratory. For planning a subsequent randomized trial, the reported sample-size illustrations make assumptions about the effect to detect, allocation, significance level, and approximation. They are planning scenarios, not observed power and not guarantees about what a larger study would find.

Finally, the record highlights how registry completeness affects statistical interpretation. Reporting analysis populations, missing-data procedures, outcome definitions, and prespecified methods would help readers distinguish planned analyses from exploratory recalculations. Such information is especially useful for pilot studies, where the principal contribution may be to clarify feasibility and inform a more definitive study rather than to settle an effectiveness question.

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 record contains limited detail about implementation and analysis. It identifies the study as randomized and single-masked but does not report the randomization procedure, allocation concealment, who was masked, or how masking was maintained. These details matter when assessing potential bias, but their absence from the registry record does not establish that a particular safeguard was or was not used.

The primary endpoint is an acceptance count among participants offered the intervention, with no corresponding acceptance measure for the standard care group. The registry does not define the survey response criterion in more detail or provide a confidence interval or inferential analysis for this count. Thus it offers a limited feasibility description rather than a comparative estimate.

For the continuous secondary outcomes, the registry presents group summaries and unadjusted comparisons, but does not report a complete analysis plan, multiplicity handling, analysis populations, or missing-data methods. It is unclear from the record whether all outcome-specific observations were available for all randomized participants. Numerical results for lactation duration are not reported in the registry record, despite its listing as a secondary outcome.

The brief summary describes a plan for 40 mothers, whereas the enrollment field records 32; the explanation is not reported in the registry record. The group summaries are also from a pilot study, and their uncertainty limits the precision of conclusions. Finally, the registry's stated follow-up frames include outcomes up to 21 days, while acceptance is assessed at 20-22 days. Details about observation beyond those stated timeframes are not reported. These record-level limitations should be kept distinct from any unreported trial procedures.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Improving Lactation Success in Black Mothers of Critically Ill Infants — NCT05147987.
• Registry record last updated 2026-09-09; status last verified 2024-11.
• Results first posted 2026-09-09.
• 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.

19. Record Summary

NCT05147987 is a completed randomized, single-masked, parallel-group pilot study sponsored by the University of Florida. It compares a discreet, hands-free wearable breast pump with an associated app against a standard mechanical breast pump without an app for Black mothers of critically ill infants in the NICU. Recorded enrollment is 32; the registry lists the study start as 2022-01-01 and primary completion as 2025-02-15.

The primary outcome is the number of participants accepting the intervention at 20-22 days. The registry reports 16 for the intervention group and zero for standard care, which did not receive the intervention. Secondary numerical results are posted for pumped milk volume, days to secretory activation, and total pumping sessions; numerical lactation-duration results are not reported in the registry record. The secondary comparisons are unadjusted recalculations, and no trial-reported analyses are listed. The record does not report a multiplicity plan, missing-data methods, or analysis populations.