Feasibility of BabyGentleStick- Adult Pilot Study: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Feasibility of BabyGentleStick- Adult Pilot Study (NCT02947646), a randomized na study. The primary outcome is Number of Adverse Events.

2. Clinical Question

These aims make the study an early feasibility and safety evaluation, not a definitive test of clinical benefit. The registry describes both safety and efficacy objectives, but the posted primary endpoint concerns adverse-event counts. The subject-feedback and device-performance objectives are described in the study summary; their measurement details and results are not reported in the registry record. The pain-response measure offers a separate, short-term outcome, but it does not replace the primary safety endpoint.

3. Trial Design

The registry record describes a randomized, open-label, crossover pilot study of BabyGentleStick. Enrollment was 20, and the listed phase is NA. The record lists two sequences: BabyGentleStick ON followed by BabyGentleStick OFF, and BabyGentleStick OFF followed by BabyGentleStick ON. Each participant was therefore assigned an order for receiving the two conditions, as described by the registered sequence labels.

In general, randomization helps determine the assigned order by chance, while a crossover design exposes participants to each condition at different points in the study. Because the same participant can contribute observations under both conditions, analyses of crossover data may need to account for the relationship between measurements from the same person. The registry record does not report whether the primary or secondary comparisons used a paired analysis, how sequence was handled, or whether period effects were assessed.

Masking is listed as none. That means the record does not describe blinding of participants or study personnel. The study is identified as completed, with a start date of 2016-11 and primary completion in 2016-12. The sponsor is Actuated Medical, Inc. Healthy adult volunteers were the intended population, according to the study summary.

The summary describes the project as a pilot focused on subject feedback, device performance, and potential harm. The registry record does not report the rationale for the planned enrollment, the allocation procedure in detail, the schedule or duration between crossover conditions, or any washout provisions. Those details matter when interpreting whether observed differences could reflect the device condition, the order of exposure, or other features of the study period. They cannot be determined from the posted record.

The ON and OFF results are reported for 19 and 20 observations, respectively, for the primary count and the secondary pain measure. The record does not explain the unequal count for the ON condition, whether observations were missing, or how the crossover structure relates to those outcome-specific sample sizes. The presence of two sequence labels does not by itself establish that the outcome summaries are paired or that a particular within-participant method was used.

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 Number of Adverse Events, measured over 24 hours after the intervention is received for each subject.

The primary endpoint is the number of adverse events, with the registry timeframe defined as 24 hours after the intervention is received for each subject. The study description says participants were to receive a follow-up phone call 24 hours post-intervention to monitor adverse events. An event count is intended to capture the number of occurrences recorded during that specified follow-up window, rather than the severity of pain or a longer-term outcome.

In a pilot device study, tracking adverse events can help characterize potential harm and inform whether the intervention and follow-up procedures are feasible to study. It is also relevant to the stated objective of ascertaining potential harm in healthy adult volunteers. The registry record does not give a fuller definition of what qualified as an adverse event, how events were attributed to each condition, or whether recurrent events were counted separately.

The posted primary summaries report zero events for BabyGentleStick ON among 19 observations and one event for BabyGentleStick OFF among 20 observations. The record does not report an inferential comparison for these counts; it states that a two-arm comparison was not estimable for this count outcome. Consequently, the counts describe the posted observations but do not establish a precise comparative rate or a causal effect. The primary endpoint is also distinct from the serious-adverse-event summaries, which separately report serious events and deaths.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a randomized crossover design with no masking. In general, randomization assigns participants to study conditions or sequences by chance, helping reduce systematic differences in assignment. In a crossover, a participant receives more than one condition in an assigned order. This can be efficient because each participant may serve as their own reference, but the observations from that person are related rather than independent. A suitable analysis usually needs to reflect that relationship and consider whether order or period could influence outcomes.

What does the crossover structure imply?

The listed sequences are ON then OFF and OFF then ON. These labels establish that order was varied, but do not provide enough information to reconstruct the statistical analysis. For example, the registry record does not say whether the posted mean difference uses paired observations, an independent-groups calculation, or another method. It also does not report whether sequence or period effects were modeled, how the time between conditions was managed, or whether there was a washout. General methodological considerations cannot establish which approach was used in this study.

The outcome-specific counts are 19 for ON and 20 for OFF. These counts may indicate the number of available observations for each condition, but the record does not explain the difference between them. It also does not state whether observations were omitted, whether every participant completed both conditions, or how missing observations were treated. Without that information, the posted counts should not be interpreted as evidence about completion or attrition beyond what the record explicitly reports.

How should the primary count be read?

The primary endpoint is a count of adverse events within the 24-hour follow-up period. Count outcomes can be analyzed in different ways depending on their distribution, exposure, and study design. General count models may account for the fact that counts are nonnegative and can be highly concentrated at zero; some methods also address over-dispersion, which occurs when variation exceeds what a simpler count model assumes. However, the registry does not report a model, a dispersion estimate, an adjustment, or an inferential primary comparison. The posted information says the two-arm comparison was not estimable for this count outcome. It would be inappropriate to substitute a newly calculated method or to assume why the comparison could not be estimated.

The reported count summaries show zero events in the ON condition and one in the OFF condition. With such sparse observed counts, the raw totals are descriptive and can be sensitive to individual events. They do not provide the same information as a model-based estimate with uncertainty. No such estimate is reported for the primary endpoint, and no unadjusted recalculation is posted for it.

What is reported for the continuous secondary outcome?

The secondary outcome is a Likert-scale score measured at 5 minutes. The registry reports means and standard deviations for each condition, followed by an unadjusted mean difference, confidence interval, and p-value. A mean describes the center of the observed scores, while a standard deviation describes the spread of individual scores around the mean. A mean difference expresses the contrast between two means in the score's units. The reported contrast is OFF relative to ON.

A confidence interval communicates uncertainty around an estimated contrast under the assumptions of the analysis. Its width reflects the estimate's precision, as well as the method used to form it. The posted interval includes zero and extends to values on either side, so the data are compatible with different directions of the mean contrast under that analysis. The p-value of 0.89 is unadjusted. It is not a measure of effect size, nor is it a probability that the observed estimate is due to chance.

Because the design is crossover, the analysis method matters: a paired contrast can use within-participant information, whereas an independent comparison treats condition summaries differently. The record does not specify which method generated the posted secondary comparison. Accordingly, the reported estimate and uncertainty can be described, but the analysis assumptions cannot be independently evaluated from the registry entry alone.

What do the planning illustrations mean?

The planning illustrations are based on fractions of the observed secondary effect and are not the trial's original design calculation. Their stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They express participants per arm for 80% power and participants per arm for 90% power, not an observed power calculation.

Under planning for 100% of the observed effect, the illustration gives 7,904 participants per arm for 80% power and 10,580 participants per arm for 90% power. Planning for 75% of the observed effect gives 14,050 participants per arm for 80% power and 18,809 participants per arm for 90% power. Planning for 50% of the observed effect gives 31,613 participants per arm for 80% power and 42,320 participants per arm for 90% power. These are hypothetical planning outputs tied to the observed estimate and stated assumptions, not evidence that the pilot had those levels of power. They do not establish the trial's intended sample size, which is not reported in the registry record.

In general, planning estimates based on an observed effect can be unstable when the originating study is small or the estimate is imprecise. A smaller effect to detect requires more information under otherwise similar assumptions. These illustrations are not a substitute for a prespecified design justified independently of the observed result, and the registry record does not report the original sample-size justification.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists one secondary outcome and zero reported analyses, while the posted results include descriptive summaries and an unadjusted comparison for the pain-response measure. It does not report a prespecified multiplicity strategy, an outcome hierarchy, or a statistical analysis plan. Without those details, readers cannot determine which comparisons were planned in advance or whether any adjustment for testing multiple outcomes was intended.

In general, multiplicity matters because examining several outcomes or comparisons can increase the chance of at least one apparently unusual result even when no corresponding effect exists. An unadjusted p-value does not account for that broader testing process. Here, the secondary result should be treated as exploratory rather than as a standalone confirmatory finding. The registry entry does not identify additional analyses that could be included in a broader multiplicity assessment.

Information about missing data is also limited. The summaries report 19 observations for ON and 20 for OFF, but the record does not explain the difference, identify missing observations, or state how any missing data were handled. It does not report whether participants completed both periods or whether the analysis used all randomized participants, only participants who completed both conditions, or another analysis population. The record also does not provide reasons for any exclusions or omissions.

These omissions are relevant in a crossover study because incomplete participation in one condition can affect which within-person comparisons are available. In general, the assumptions used to handle missing outcomes can influence estimates and their uncertainty. No imputation method, sensitivity analysis, or missing-data assumption is reported in the registry record. The registry also does not report interim analyses or stopping rules; their presence or absence cannot be inferred from the lack of a description.

The primary count comparison is specifically marked as not estimable, and no inferential primary analysis is posted. The record does not explain whether this arose from the data structure, the analysis method, or another reason. Thus, statistical interpretation is constrained not only by the small pilot setting but also by missing documentation about populations, missing outcomes, and analysis decisions.

11. 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 non-serious adverse event terms

The serious-adverse-event summaries report zero serious events in both conditions and zero deaths in both conditions. The listed numbers at risk are 19 for BabyGentleStick ON and 20 for BabyGentleStick OFF. These figures describe the observations represented in the registry summaries; they do not establish that serious events could not occur or provide a precise estimate of their likelihood.

The separate other-adverse-event counts are zero for ON and one for OFF. The primary endpoint also reports zero events for ON and one for OFF. The registry record does not provide additional details about the nature of the one non-serious event, its timing, or its attribution. It lists no serious adverse-event terms.

In general, zero observed serious events in a small pilot should be read as an absence of reported events in the observed study data, not as proof of no risk. The sample is limited, and the follow-up for the primary endpoint is defined as 24 hours after each intervention. These summaries characterize short-term reporting in this study; they do not describe longer-term safety or establish comparative safety.

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

The registry record supports a narrow description of what was observed in this pilot. It reports the number of adverse events recorded for each device condition during the defined follow-up window, separate serious-event and death counts, and a short-term secondary pain-response score. It also records an unadjusted mean difference and associated uncertainty for the secondary score. These details are useful for understanding what outcomes were posted and how limited the evidence is.

The record does not provide an estimable inferential comparison for the primary adverse-event count. It therefore does not establish that ON and OFF differ on the primary endpoint. The secondary comparison is imprecise and unadjusted, and the registry does not describe the analysis method sufficiently to assess how the crossover structure was handled. The absence of a clear separation in the secondary comparison does not prove equivalence, and the small number of observations does not rule out differences that the study could not estimate precisely.

The study is described as a pilot focused on subject feedback, device performance, and potential harm in healthy adult volunteers. The results posted in the registry do not include reported findings for subject feedback or device performance. Nor do the short-term outcome summaries establish a general effect in populations beyond the healthy adult volunteers described in the study summary. The registry record does not report longer follow-up, a sample-size justification, or the statistical plan needed to frame the findings as confirmatory evidence.

Accordingly, the posted information is best understood as a limited feasibility-era record of observed outcomes, not a definitive evaluation. It cannot establish broad safety, benefit, or lack of effect. It also cannot show that a difference is absent merely because a comparison is unestimated or inconclusive. Conclusions should remain specific to the outcomes, timeframes, and observations actually reported.

13. Why This Trial Matters Statistically

This study illustrates why statistical interpretation depends on more than whether a result is numerically different. The primary endpoint is a sparse event count, and the registry record reports a small difference in observed counts but no estimable inferential comparison. That distinction matters: a descriptive count is not the same as an estimate of the contrast with a quantified level of uncertainty.

The crossover design also highlights the importance of documenting analysis methods. Participants were assigned to ON-then-OFF or OFF-then-ON sequences, and each condition has an outcome summary. In general, measurements from the same participant are related. Whether a comparison accounts for that relationship can influence the estimate and its precision. The registry record does not report enough methodological detail to establish how the posted secondary comparison treated that dependence.

The pain-response result provides an example of why a p-value alone is not a complete interpretation. The posted estimate is accompanied by uncertainty that spans both directions, and the p-value is unadjusted. Neither the p-value nor the point estimate can establish equivalence or settle the primary safety question. Precision, study design, and endpoint relevance all matter.

The record also distinguishes pilot planning from a definitive sample-size calculation. The posted planning illustrations are tied to fractions of the observed effect and stated assumptions. They are not the original design rationale and are not observed power. In general, this distinction prevents a hypothetical planning output from being mistaken for evidence about what the study was designed to detect.

Finally, the missing details are themselves statistically important. The registry does not report the sample-size justification, missing-data handling, multiplicity approach, or analysis populations. Recognizing those gaps is part of responsible interpretation: it keeps the conclusion aligned with the information the record actually documents.

14. 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 trial-specific limitation is the small pilot enrollment of 20, with outcome summaries based on 19 observations for ON and 20 for OFF. The registry record does not explain the unequal counts or state whether all participants completed both crossover conditions. This limits understanding of the available comparisons and of how representative the posted summaries are of everyone enrolled.

The primary endpoint is a count with very few events, and the registry says a two-arm comparison was not estimable. No inferential estimate or uncertainty interval is reported for that endpoint. The result therefore cannot provide a precise comparative assessment of adverse-event counts. The record also does not describe how adverse events were defined, how repeated events were treated, or how they were attributed to each condition.

The crossover design creates additional questions that cannot be resolved from the registry entry. It does not report the period between interventions, any washout, whether order or period effects were assessed, or whether the secondary comparison accounted for within-participant pairing. Masking is listed as none, but the record does not describe any steps used to limit the influence of expectations or knowledge of condition on outcome reporting.

Other limitations include the absence of a reported sample-size justification, analysis plan, missing-data methods, multiplicity approach, and analysis-population definitions. The registry summary describes feedback and device-performance objectives but does not report their results. Follow-up for the primary endpoint is defined as 24 hours after the intervention; longer-term outcomes are not reported in the registry record. These gaps make the posted results useful mainly as a limited account of the outcomes recorded, rather than a full statistical evaluation.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Feasibility of BabyGentleStick- Adult Pilot Study — NCT02947646.
• Registry record last updated 2022-12-29; status last verified 2022-05.
• Results first posted 2022-06-16.
• 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.

18. Record Summary

NCT02947646 is a completed, randomized, open-label crossover pilot of BabyGentleStick in healthy adult volunteers. Enrollment was 20. The listed sequences were ON followed by OFF and OFF followed by ON. The study summary describes objectives to obtain subject feedback, assess device performance, and ascertain potential harm.

The primary endpoint was number of adverse events during the 24 hours after intervention. The posted counts were zero for ON among 19 observations and one for OFF among 20; the registry record says a two-arm comparison was not estimable. The secondary pain-response score at 5 minutes was reported as a mean and standard deviation for each condition, with an unadjusted comparison.

The registry record does not report a sample-size justification, detailed crossover analysis methods, missing-data handling, or results for the feedback and device-performance objectives. The posted information is therefore limited to observed outcome summaries and the reported secondary comparison.