CoolSculpting of the Flank With Alternate Treatment Parameters: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for CoolSculpting of the Flank With Alternate Treatment Parameters (NCT02081196), a na na study. The primary outcome is The Number of Device and/or Procedure-Related Adverse Events.

2. Clinical Question

The central question is therefore about safety reporting under the alternate treatment parameter, rather than a randomized test of treatment benefit. The registry’s stated purpose includes evaluating safety and efficacy, but the primary outcome specified in this record is the number of device- or procedure-related adverse events. The flank arrangement supplies a within-subject reference for the study, while the registry’s own warning limits how directly the treated and untreated entries should be interpreted as a comparison.

3. Trial Design

The registry identifies this as a completed, single-group device study of CoolSculpting of the flank with alternate treatment parameters. Enrollment was 45. The study began on 2014-02-18, and primary completion was recorded on 2014-06-27. Phase is recorded as NA, allocation as NA, and masking as NONE. The sponsor is Zeltiq Aesthetics.

In the arm description, each subject served as their own control: one flank received CoolSculpting and the contralateral flank remained untreated. This design makes measurements from the two flanks potentially related because both belong to the same subject. However, the registry explicitly notes that this was not a randomized comparison and that the arms are not a like-for-like control comparison. The untreated flank should therefore not be described as though it were an independently randomized control group.

The primary outcome is a count of device- or procedure-related adverse events. Reports were collected from enrollment through the 16-week follow-up visit, described as approximately 5 months. The investigator determined the relationship of an event to the device or procedure. The safety population is defined as all subjects treated with CoolSculpting. The record lists image identification and subject satisfaction as secondary outcomes.

The registry records four outcome measures and two analyses, but the details of those analyses are not reported in the registry record. The statistical analysis plan, any planned adjustment for within-subject dependence, and the rationale for the enrollment size are also not reported in the registry record. The record does not establish that the study was designed to estimate a comparative treatment effect. Its structure and stated primary outcome are best read as a device safety assessment with an untreated contralateral flank included in the study arrangement.

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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The safety population includes all subjects treated with CoolSculpting.

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 The Number of Device and/or Procedure-Related Adverse Events, measured over Enrollment through 16 weeks post-treatment visit, which is approximately 5 months.

The primary endpoint is the number of adverse events judged to be related to the device or procedure. Collection was specified from enrollment through the 16-week post-treatment visit, which the registry describes as approximately 5 months. The investigator determined whether each reported event was related to the study device or procedure. The safety population includes all subjects treated with CoolSculpting.

A safety count can help describe the observed burden of events during a defined follow-up period and identify whether serious events were reported. Such counts are useful because safety assessment concerns both the type and frequency of events, as well as their timing and assessed relationship to the intervention. This endpoint is not, by itself, a measure of fat reduction or patient satisfaction. The registry lists image identification and subject satisfaction separately as secondary outcomes.

The outcome title specifies a number of events, while the posted adverse-event entries are expressed as numbers affected in the serious and other adverse-event categories. Those entries should not automatically be read as the total number of event episodes: the registry record does not explain whether any subject experienced more than one event or how the primary event count relates to the affected entries. A complete interpretation therefore needs to preserve the distinction between a count of events and a count of subjects affected. A more detailed definition or reconciliation is not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary outcome is a count, so its natural descriptive form is the number of qualifying events observed during the specified follow-up. The registry says adverse events were collected from enrollment through the 16-week post-treatment visit, described as approximately 5 months. Investigators assessed whether events were related to the device or procedure. A count is straightforward to understand, but its meaning depends on exactly what is counted: individual event episodes, subjects with at least one event, or another unit. The primary outcome title refers to events, while the posted adverse-event data use affected counts. The relationship between these presentations is not reported in the registry record.

For a count outcome, it is also important to know the amount of observation contributing to the count. The record gives the safety population as all subjects treated with CoolSculpting and lists 45 at risk in each adverse-event entry. It does not give additional follow-up detail for individual subjects, nor does it state a person-time analysis. The reported counts should therefore be read according to the registry’s definitions, without converting them into rates or assuming uniform observation beyond what the record states.

General statistical explanation: counts may vary more than a simple probability model expects when observations are heterogeneous or when some subjects are more likely than others to experience events. This is called over-dispersion. If over-dispersion is present, methods that assume less variability can produce uncertainty estimates that are too narrow. Whether over-dispersion was assessed or whether a count model was used is not reported in the registry record. No model, standard error, confidence interval, or hypothesis test for the primary outcome is described.

The flank arrangement also matters for analysis. Because each subject had a treated flank and an untreated contralateral flank, paired observations could be correlated. General statistical explanation: a paired analysis uses the within-subject relationship rather than treating each flank as an unrelated observation. That can affect both the estimated contrast and its uncertainty. The record does not report a paired statistical method, and its caution that the arms are not a like-for-like control comparison should be kept in view. The registry does not describe random allocation or a formal inferential comparison between flanks.

General statistical explanation: a confidence interval communicates the precision of an estimate by showing a range of values compatible with the data and the method used. A narrow interval indicates greater precision under that method; a wide interval indicates more uncertainty. An interval does not remove bias from a nonrandomized design, incorrect outcome definitions, or incomplete follow-up. No confidence interval for the primary safety endpoint is reported in the registry record, so the precision of the endpoint estimate cannot be assessed from the listed counts alone.

General statistical explanation: a p-value measures how unusual data would be under a specified statistical model and null hypothesis. It does not measure the probability that a treatment works, nor does it quantify the size or clinical importance of an effect. The registry record does not report a p-value or a statistical test for the primary endpoint. A reader should not infer that a test was performed simply because the record lists analyses or outcomes.

The record lists four outcome measures and two analyses, but it does not identify the methods used for those analyses in the registry record for interpretation. A statistical analysis plan, handling of repeated events, treatment of missing observations, and any adjustment for multiple outcomes are not reported in the registry record. These omissions prevent a detailed reconstruction of the analysis or a determination of whether the reported entries correspond to prespecified summaries.

The sample-size assumptions described in the record concern a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. The illustration is not the trial’s own design justification. It should not be interpreted as observed power or as evidence that the trial was prospectively sized for a particular effect. The record does not report a protocol-based sample-size justification. In general, planning calculations depend on assumptions about the effect to detect, variability, allocation, and analysis; changing those assumptions changes the planned sample size. They do not establish the precision of the results actually observed.

When a registry reports a number of subjects affected, that number is a descriptive count in its stated category. It is not necessarily the number of event episodes, and it does not reveal event severity, duration, recurrence, or causal certainty unless those details are reported separately. The record identifies zero serious events and provides other-event affected counts, but does not provide the event narratives or a complete breakdown of the primary related-event count. The appropriate statistical reading is therefore descriptive and bounded by the definitions available in the registry.

10. Multiplicity, Missing Data and Analysis Populations

The record lists four outcome measures and two analyses. It names image identification and subject satisfaction as secondary outcomes, alongside the primary count of device- or procedure-related adverse events. The results for the secondary outcomes are not reported in the registry record. The relationship between all listed measures and the two analyses is also not reported in the registry record.

When several outcomes or analyses are examined, the chance of finding an apparently notable result can increase if no adjustment or prespecified hierarchy is used. General statistical explanation: multiplicity methods address this issue by controlling how evidence is interpreted across multiple tests or outcomes. Whether any such method was planned or applied is not reported in the registry record. The record does not state whether the primary outcome was the sole confirmatory analysis or whether secondary outcomes were treated as exploratory.

Missing-data methods are not reported in the registry record. The enrollment and safety population are described, but the record does not state whether any follow-up observations were missing, how incomplete follow-up was handled, or whether subjects were excluded from particular outcome summaries. The registry does not report imputation, sensitivity analyses, or a complete-case approach.

Analysis populations beyond the safety population are not reported in the registry record. The safety population is defined as all subjects treated with CoolSculpting, but the record does not explain whether the image-identification or satisfaction outcomes used the same population. These gaps limit assessment of selection, multiplicity, and missing-data effects. They also mean the reported safety entries should not be taken as a full account of how every planned outcome was analyzed.

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 entries each list 45 at risk and 0 affected: the systemic adverse-event group, the CoolSculpting-treated flank group, and the untreated contralateral flank group. These are the serious-event figures reported in the registry. A zero affected count means no serious adverse events were recorded in those entries; it does not prove that the underlying risk is zero.

For other adverse events, the registry lists 7 affected in the group titled CoolSculpting of the Flank -Subjects With Systemic AEs, 12 affected in the Flank Treated With CoolSculpting Group, and 0 affected in the UnTreated Contralateral Flank group. Each entry lists 45 at risk. These are separate registry categories, not values that should be added together. The record does not explain whether categories overlap or whether affected counts are unique subjects or event episodes.

These adverse-event entries should also be distinguished from the primary endpoint’s stated count of device- or procedure-related events. Investigators assessed relatedness, but a reconciliation between that endpoint and the affected-count entries is not reported in the registry record. The safety figures are descriptive and do not by themselves establish a causal contrast between flanks.

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

The registry supports a limited descriptive statement: the posted serious adverse-event entries list zero affected in the systemic, treated-flank, and untreated contralateral-flank groups, while the other-event entries list affected counts of 7, 12, and 0, respectively, under their stated group labels. The record specifies 45 at risk for each entry. These figures describe what was recorded in the categories presented.

They do not establish that CoolSculpting is free of serious adverse events, that all reported events were caused by treatment, or that the treated flank differs reliably from the untreated flank. The study was not a randomized comparison, and the registry explicitly cautions that the arms are not a like-for-like control comparison. The within-subject arrangement is relevant, but the method for analyzing paired observations is not reported in the registry record.

The primary endpoint is the number of device- or procedure-related adverse events. The record describes investigator assessment of relatedness, but it does not provide a complete explanation of how this endpoint count corresponds to the affected counts in the posted safety entries. Nor does it report uncertainty estimates or a formal statistical comparison. The observed entries should not be read as a precise estimate of comparative risk.

The stated purpose includes safety and efficacy, but the posted information does not report results for the listed secondary outcomes of image identification and subject satisfaction. It therefore does not establish an effect on subcutaneous fat reduction, image recognition, or satisfaction. The safety data alone cannot answer those efficacy questions.

More broadly, absence of a reported result is not evidence that an outcome was measured and found to have no effect. Details of analysis, missing data, and outcome-specific results are not reported in the registry record. The most defensible interpretation is confined to the adverse-event entries and their stated categories, with uncertainty about endpoint correspondence and comparison methods acknowledged.

13. Why This Trial Matters Statistically

This study is statistically notable because the treatment arrangement is within-subject: each subject had a CoolSculpting-treated flank and an untreated contralateral flank. Such designs can make use of paired information, but the relationship between observations from the two sides needs to be reflected in the analysis. The registry does not report whether a paired method was used, and it cautions that the groups are not a like-for-like control comparison.

The endpoint also illustrates a common distinction in safety reporting: an outcome may be described as a count of events while a registry’s adverse-event breakdown reports numbers affected. Those quantities need not mean the same thing if a subject can experience more than one event. The record does not explain how its primary event count relates to the affected entries, so the distinction is important when interpreting the posted data.

The serious-event entries report zero affected in each listed category, while the other-event entries vary across their group labels. These are informative descriptive observations, but without a stated inferential method or uncertainty estimate they do not quantify how precisely any underlying event frequency is known. General statistical explanation: rare or infrequent events are often difficult to characterize precisely in a study with limited observations, even when no serious events are recorded. The registry does not report a precision estimate for these results.

Finally, the registry lists multiple outcomes but does not report results for the secondary measures or its analysis plan. This makes the record a useful example of why study design, outcome definitions, analysis populations, and missing-data methods matter alongside headline counts. Statistical interpretation depends not only on the recorded values but also on how those values were defined and compared.

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 registry record does not provide the detailed protocol, full eligibility criteria, participant characteristics, or additional treatment-parameter settings. Those details would help establish how broadly the safety findings apply and how closely the intervention can be characterized. The record identifies the device and alternative-parameter purpose but does not report further specifications.

The study is a single-group design with a treated flank and an untreated contralateral flank. The registry states that it was not a randomized comparison and that the arms are not a like-for-like control comparison. No statistical method for accounting for within-subject pairing is reported. These features limit causal or comparative interpretation of the flank entries.

The primary outcome is described as a number of device- or procedure-related adverse events, but the posted adverse-event entries are presented as affected counts. The record does not explain whether these entries count people or event episodes, whether categories overlap, or how they map to the primary endpoint. A complete event-level breakdown, including event descriptions and timing, is not reported in the registry record.

The record does not report confidence intervals, formal tests, analysis methods, handling of missing data, a multiplicity strategy, or the results for image identification and subject satisfaction. It also does not report a protocol-based sample-size justification. These omissions constrain assessment of precision, analysis choices, and the completeness of the outcome picture.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: CoolSculpting of the Flank With Alternate Treatment Parameters — NCT02081196.
• Registry record last updated 2021-03-01; status last verified 2020-09.
• Results first posted 2021-03-01.
• 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

NCT02081196 is a completed, single-group device study titled CoolSculpting of the Flank With Alternate Treatment Parameters. It evaluated the Zeltiq CoolSculpting System for non-invasive reduction of the subcutaneous fat layer. Enrollment was 45. The record lists a start date of 2014-02-18 and primary completion on 2014-06-27.

Each subject had one flank treated and the contralateral flank untreated. The primary outcome was the number of device- or procedure-related adverse events from enrollment through the 16-week post-treatment visit, described as approximately 5 months. The registry reports zero serious adverse events affected in each listed group and provides other-event affected counts under systemic, treated-flank, and untreated-flank labels. Image identification and subject satisfaction are listed as secondary outcomes, but their results are not reported in the registry record.

The record cautions that the study was not a randomized comparison and that the arms are not a like-for-like control comparison. Detailed analysis methods, missing-data procedures, and the relationship between the primary event count and affected entries are not reported in the registry record.