Multicenter Trial of Magnetic Mini-Mover for Pectus Excavatum: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Multicenter Trial of Magnetic Mini-Mover for Pectus Excavatum (NCT01327274), a na na study. The primary outcome is Number of Participants With Adverse Reactions.

2. Clinical Question

In statistical terms, this is a descriptive safety and efficacy study without a concurrent control. The primary endpoint asks how many participants experienced an adverse reaction under the study’s monitoring, rather than whether the procedure changed risk relative to another treatment or no treatment. The registry also names secondary outcomes concerning comfort and brace wear, chest-wall correction by Pectus Severity Index, and patient satisfaction during treatment. Those outcomes provide additional areas of interest, but their definitions and results are not reported in the registry record in the registry record for this analysis. The study’s small, selected cohort and lack of randomization limit how broadly its findings can be generalized and how confidently outcomes can be attributed to the procedure.

3. Trial Design

The registry describes a multicenter, non-randomized study of the Magnetic Mini-Mover Procedure for pectus excavatum. It is listed as a single-group study, with a Treatment Arm and enrollment of 15. The study status is completed. The recorded start is 2011-12, and primary completion is 2016-11.

The study summary calls the trial Phase 3, while the registry’s phase entry is NA; a formal phase designation is therefore not reported in the registry record. Allocation is listed as NA, and masking is listed as NONE. These design features are consistent with an open, non-randomized intervention study, not a masked randomized comparison. No separate control arm is described.

The intervention is identified as the Magnetic Mini-Mover Procedure (Magnimplant), a device intervention. The summary describes an outpatient procedure using a magnetically coupled implant. The arm description specifies otherwise healthy patients aged 8-14 years with severe pectus excavatum, defined there as PSI > 3.5. It also describes outpatient surgery. Details beyond the information in that description are not reported in the registry record.

The primary outcome is the number of participants with adverse reactions during treatment, with the timeframe stated as 24 months. The listed secondary outcomes address comfort and brace wear during treatment, chest-wall correction by Pectus Severity Index, and patient satisfaction during treatment. The registry lists four outcome measures and one analysis, but a fuller account of the analysis methods is not reported in the registry record.

Because the trial has no randomized comparator, its results can describe events and outcomes observed in the treated group but cannot isolate the procedure’s effect from other explanations. The registry does not report a protocol, a sample-size justification, or enough detail to assess how participants were selected or followed through the full outcome period.

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 Participants With Adverse Reactions, measured over During treatment, 24 months.

The primary endpoint is the number of participants with adverse reactions during treatment, over a stated timeframe of 24 months. It is a participant-count outcome: it records whether participants experienced an adverse reaction, rather than measuring the number of events per participant or the time until an event. The description says that all adverse reactions were recorded and reported. It includes complications from implanting the device and complications arising during application of the external device, with examples such as skin changes, infection, and changes in cardiac electrical function.

Safety outcomes are used to characterize the types and frequency of unwanted events observed during a clinical intervention. A participant count is straightforward to interpret as a summary of how many people had an event, but the count alone does not convey the range, timing, duration, or consequences of reactions. The registry also gives serious and other adverse-event counts separately. Those categories should not be treated as interchangeable with the broader primary endpoint: the record’s primary outcome description includes all adverse reactions, while the structured safety figures distinguish serious from other events.

The primary endpoint’s purpose is descriptive in this single-group study. Without a comparator, the recorded number does not estimate how much the procedure changes adverse-reaction risk relative to an alternative. The registry record does not report a more detailed endpoint definition, an operational rule for counting participants with multiple reactions, or the analysis population used for this outcome.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a single-group design estimate?

A single-group study describes outcomes among participants who receive the intervention. For a participant-count endpoint, the basic result is the number of participants recorded with the outcome. This can be useful for documenting observed events and describing what happened during follow-up. It does not directly estimate a contrast between the intervention and a comparator, because no concurrent comparator is available. In a randomized comparison, allocation helps make groups comparable on average; that protection against confounding is not available in this non-randomized, single-group study.

The registry identifies the trial as single-group and non-randomized, with allocation listed as NA and masking listed as NONE. Consequently, the adverse-event results should be understood as observations in the Treatment Arm. They cannot show what the same participants’ event experience would have been under a different approach. General differences in patient characteristics, clinical care, or observation can influence outcomes, but the record does not provide enough detail to assess those influences.

What does a participant count mean?

A participant-count outcome counts people who experienced an event, not the total number of event episodes. A participant could experience more than one event, so a participant count and an event count answer different questions. The primary endpoint is described as the number of participants with adverse reactions. The structured safety data separately report participants with serious and other adverse events. The registry does not report whether participants could appear in both categories or how repeated reactions were handled for the primary endpoint. The categories should not be added together to infer a total number of affected participants.

Likewise, event terms and participant counts are not automatically equivalent. The record lists two cable-breakage terms with percentages, but does not explain whether each term corresponds to a different participant or whether a participant could have more than one listed event. The percentages should be read as reported, without treating their sum as a rate for unique participants.

How should uncertainty be considered?

A confidence interval is a statistical range that expresses uncertainty around an estimate under specified assumptions. In general, intervals help readers see how precisely a study estimates an outcome; they do not guarantee that the true value lies within the interval, and they do not correct design limitations such as the absence of a comparator. The registry record does not report confidence intervals for the adverse-event results. It is therefore not possible to judge their statistical precision from an interval in the available information.

Small studies often produce imprecise estimates because each participant’s outcome can have substantial influence on the observed result. This is a general statistical consideration, not a claim about an unreported interval for this study. The single-group design adds a separate limitation: even a precise description of the observed cohort would not establish a causal comparison with an alternative.

Why can event rates be harder to interpret than counts?

Counts are tied to the observed group and follow-up experience. To compare rates meaningfully, readers need a clear denominator, consistent outcome definitions, and comparable observation periods. Time at risk may differ between participants, and repeated events may occur. Methods for handling these features are not reported in the registry record. In general, over-dispersion means that observed variation exceeds what a simple statistical model expects. It can matter when event counts vary more widely than a model assumes, but the registry record does not state that an over-dispersion model was used or provide enough information to assess whether one was appropriate.

What can planning calculations tell a reader?

Sample-size calculations can illustrate the amount of information a future study might need under stated assumptions. The planning framework described for this analysis uses a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; it defines the target effect as a stated fraction of the observed effect. These are planning assumptions, not evidence that the trial itself was designed with those assumptions. The sample-size figures are illustrations, not observed power and not a retrospective measure of whether the study succeeded. The registry record does not report its own sample-size justification or design assumptions. No particular planning result should be interpreted as a feature of the original trial unless it is explicitly reported in the registry record.

What analysis details are available?

The registry lists one analysis, but the analysis method, any adjustment, the handling of missing observations, and the analysis population are not reported in the registry record. Without those details, the results are best read as descriptive recorded counts. No unadjusted re-calculation or sponsor analysis comparison is reported in the registry record in the registry record for this analysis.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists four outcome measures, including the primary adverse-reaction endpoint and named secondary outcomes for comfort and brace wear, chest-wall correction by Pectus Severity Index, and patient satisfaction. It also lists one analysis. The statistical plan for handling multiple outcomes or multiple comparisons is not reported in the registry record. Without that plan, readers cannot determine whether any multiplicity adjustment was prespecified or how the chance of false-positive findings was managed across outcomes. The absence of a reported adjustment should not be taken to mean that none was used.

Missing-data procedures are not reported in the registry record. The record does not state how incomplete follow-up, missing outcome measurements, or participants who discontinued treatment were handled. Nor does it report the number of participants with available data for each outcome. Enrollment and the at-risk counts are reported, but they do not establish that every participant had complete observation through the full outcome timeframe.

The analysis population is also not reported in the registry record. It is not clear whether analyses were based on all enrolled participants, those who received the procedure, or a subset with recorded outcome data. These choices can affect interpretation, especially when follow-up is incomplete or participants differ in how much observation they contribute.

These reporting gaps limit assessment of the outcome results. They do not establish that data were missing or that an analysis problem occurred; they mean the registry record does not describe the relevant methods. In a single-group study, complete definitions and follow-up information are particularly useful for interpreting whether the recorded adverse-event counts reflect consistent observation across participants.

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 serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: acute cable breakage requiring urgent explant (6.7%), nonacute cable breakage requiring explant (6.7%).

The registry reports 2 participants with a serious adverse event among 15 at risk, and 4 with another adverse event among 15 at risk. It reports 0 deaths. These are separate serious and other event summaries; the record does not say whether the categories overlap, so they should not be added to create a total number of participants with an event.

The two serious-event terms listed are acute cable breakage requiring urgent explant and nonacute cable breakage requiring explant. Each is reported as 6.7%. The registry does not clarify whether the terms refer to distinct participants or whether they represent all serious events. The terms and percentages therefore describe what is listed, but do not support a calculation of unique affected participants.

These figures are descriptive safety observations, not a comparison with an untreated group or another procedure. The primary endpoint covers adverse reactions more broadly, while these structured figures distinguish serious and other events. A fuller account of event timing, severity, relatedness, follow-up completeness, and uncertainty is not reported in the registry record. The counts can identify what was recorded in the Treatment Arm, but they cannot establish causation or comparative risk.

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

The posted safety data describe adverse events recorded in a single Treatment Arm. They report 2 participants with a serious adverse event among 15 at risk, 4 with another adverse event among 15 at risk, and 0 deaths. Two serious-event terms—acute cable breakage requiring urgent explant and nonacute cable breakage requiring explant—are each listed as 6.7%. These are observations from the study, not estimates of a difference between treatments.

Because the study is non-randomized and single-group, its design cannot determine whether the observed events occurred more or less often than they would have under another treatment or no intervention. It also cannot separate the intervention’s effects from other influences on outcomes. The data do not establish that the procedure caused a listed event, nor do they show that no other risks occurred. The primary endpoint is intended to capture adverse reactions more broadly, but an overall result for that endpoint is not reported in the registry record in the registry record for this analysis.

The study summary describes the procedure as an outpatient intervention for patients aged 8-14 years with severe pectus excavatum. Findings from this selected group cannot automatically be generalized to patients outside the described population, to different care settings, or to alternative device use. Results for the named secondary outcomes are not reported in the registry record in the registry record, so the listed safety results do not answer questions about comfort, chest-wall correction, or satisfaction.

The record does not report confidence intervals, detailed analysis methods, missing-data procedures, or the analysis population. Those omissions limit assessment of precision and completeness. The findings are best understood as a small study’s recorded safety experience, rather than proof of a comparative benefit, harm, or absence of risk.

13. Why This Trial Matters Statistically

This trial is statistically notable because it evaluates a device-based procedure in a multicenter, single-group setting without randomization or a concurrent comparator. Such studies can document feasibility and observed safety events, but their results answer a narrower question than a controlled comparison. The adverse-event counts describe what was recorded among treated participants; they do not estimate a treatment effect relative to another approach.

The distinction between participant counts and event terms is important. The primary endpoint is framed as the number of participants with adverse reactions, whereas the registry separately reports serious and other adverse-event counts and lists cable-breakage terms. Because the record does not explain overlap or repeated events, readers should not combine these entries into a total. This is a general issue in safety reporting: the unit of analysis must be clear before counts can be interpreted or compared.

The study also illustrates why precision and design should be considered separately. Confidence intervals or other uncertainty measures would help characterize how precisely the safety experience was estimated, but none are reported in the registry record. Even precise single-group estimates would still lack a causal comparison. Conversely, a descriptive count can be informative about events observed in the cohort while remaining insufficient to establish comparative risk.

Finally, important analytic details—including missing-data handling, the analysis population, and the trial’s own sample-size rationale—are not reported in the registry record. These details help readers judge the completeness and intended scope of results. The record’s limits do not negate the value of documenting events; they define what statistical conclusions the available evidence can support.

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 limitation is the single-group, non-randomized design. Without a concurrent comparator and random allocation, the study cannot estimate a comparative effect or distinguish the intervention’s contribution from other influences. The absence of masking, recorded as NONE, may also be relevant to how outcomes were observed or reported, although the registry record does not describe whether or how this affected event ascertainment.

The enrolled population is described as otherwise healthy patients aged 8-14 years with severe pectus excavatum, with PSI > 3.5 specified in the arm description. The results may not apply to populations outside this description. The registry does not report detailed participant characteristics or selection procedures, so the representativeness of the cohort cannot be assessed further.

The safety information has limited detail. The record reports serious and other adverse-event counts, two serious-event terms with percentages, and 0 deaths, but it does not clarify overlap among event categories, repeated events, event relatedness, timing, or completeness of follow-up. The primary endpoint encompasses adverse reactions broadly, yet an overall primary-endpoint result is not reported in the registry record in the registry record for this analysis.

Confidence intervals, missing-data methods, the analysis population, and the trial’s own sample-size justification are not reported in the registry record. These gaps limit assessment of precision, completeness, and analytic choices. The registry names secondary outcomes, but their results are not reported in the registry entries. These limitations mean the findings should be read as descriptive observations from the recorded cohort, not as a comprehensive or comparative assessment.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Multicenter Trial of Magnetic Mini-Mover for Pectus Excavatum — NCT01327274.
• Registry record last updated 2018-11-08; status last verified 2018-10.
• Results first posted 2018-05-17.
• 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.

18. Record Summary

The registry record describes a completed, multicenter, non-randomized, single-group study of the Magnetic Mini-Mover Procedure (Magnimplant) for pectus excavatum. It lists enrollment of 15 and describes otherwise healthy patients aged 8-14 years with severe pectus excavatum. The study summary calls it Phase 3, while the phase field is NA.

The primary outcome is the number of participants with adverse reactions during treatment, over a stated 24-month timeframe. The Treatment Arm safety results list 2 participants with a serious adverse event among 15 at risk, 4 with another adverse event among 15 at risk, and 0 deaths. Acute cable breakage requiring urgent explant and nonacute cable breakage requiring explant are each listed as 6.7%.

There is no randomized comparator. Analysis methods, confidence intervals, missing-data handling, and the analysis population are not reported in the registry record. The results therefore describe recorded events in the Treatment Arm rather than a comparative treatment effect.