Patient Experience Study of Deoxycholic Acid Injection: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Patient Experience Study of Deoxycholic Acid Injection (NCT02007434), a randomized phase 3 study. The primary outcome is Change From Baseline in Pain Visual Analog Scale Scores.

2. Clinical Question

The study's stated objectives included assessing the safety of subcutaneous deoxycholic acid injections and evaluating interventions relative to placebo, particularly for pain, bruising, and swelling or edema. The primary endpoint concerns pain-score change; it does not by itself describe the full safety assessment or all patient-experience outcomes.

3. Trial Design

This was a phase 3, randomized, double-blind, parallel-group study at a single center. The registry lists enrollment of 84 and a completed study. The recorded study start was 2013-12, and primary completion was 2014-06. The sponsor was Kythera Biopharmaceuticals.

The official title describes a two-factor patient-experience management study. The intervention descriptions organize treatment into four paradigms, each with a deoxycholic acid injection group and a placebo injection group. All groups received injections on Day 0 and a cold compress. The further management measures varied by paradigm: the second added topical and injectable anesthetics; the third also included oral loratadine and ibuprofen; and the fourth added a compression chin strap. Paradigm 1 did not list those additional measures.

The injection descriptions specify deoxycholic acid at 2 mg/cm², delivered in 0.2 mL injections, with either 6 or 8 mL depending on baseline clinician-rated submental fullness grade. Placebo groups had the corresponding placebo injections, with the same stated volume alternatives. The registry record does not report the allocation ratio, the number assigned to each group at randomization, or details of how randomization and masking were implemented.

The primary endpoint population was the safety analysis set with available data at baseline and Day 84. The number with endpoint data varied across the eight listed groups. These endpoint counts should not be treated as the full enrollment or as evidence about why data were unavailable. Reasons for missing endpoint data and the handling of missing values 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.

Only the first 6 of 8 groups are shown.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Safety analysis set with available data at both time points

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.

Population: Safety analysis set

Only the first 6 of 9 groups are shown.

6. Primary Endpoint

The registry lists the primary outcome as Change From Baseline in Pain Visual Analog Scale Scores, measured over Baseline and Day 84.

The primary endpoint was change from baseline in pain visual analog scale scores, assessed at baseline and Day 84. Participants marked a 100 mm line at the point that best represented pain associated with the treated area. The anchors were 0 for no pain and 100 for the most severe pain possible. The outcome is reported in units on a scale, as a median with a full range.

A pain scale can capture a participant's subjective experience in a form that can be compared across assessments. A change score focuses on how a person's rating at follow-up differs from their baseline rating, rather than describing only the follow-up level. The median gives the middle value in the observed group distribution and is less affected by extreme observations than the arithmetic mean. A full range conveys the lowest and highest observed changes, but does not show how values are distributed between those limits.

In each of the eight groups, the posted median change was 0. The reported ranges varied by group: Paradigm 1 deoxycholic acid, -2 to 5; Paradigm 1 placebo, 0 to 0; Paradigm 2 deoxycholic acid, -2 to 1; Paradigm 2 placebo, 0 to 0; Paradigm 3 deoxycholic acid, 0 to 2; Paradigm 3 placebo, -1 to 0; Paradigm 4 deoxycholic acid, -1 to 1; and Paradigm 4 placebo, -1 to 0. The registry record does not define the direction of the change-score calculation, so the signs should be read as recorded rather than assigned a clinical meaning.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the median and full range describe?

The primary endpoint is summarized by a median and full range. A median identifies the central observation after values are ordered. It is useful when a mean could be strongly influenced by extreme observations, but it does not describe the distribution's shape or the precision of the estimated center. The full range gives the smallest and largest observed values; it is sensitive to the most extreme observations and does not indicate how many participants had values near either limit.

Here, the median change is 0 for each group, while some ranges extend below or above 0. That combination means that the central recorded change is 0 even though not every observed change was 0. It does not imply that all participants experienced no change. Nor does a range quantify uncertainty about the median in the way a confidence interval would.

What does ANCOVA contribute?

ANCOVA is a model-based method that compares group outcomes while accounting for other variables included in the model. The registry identifies the method as ANCOVA and describes the estimates as least-squares mean placebo-adjusted differences. A least-squares mean is an adjusted model estimate, not simply the raw median reported for each group. The registry record does not report the model covariates, model diagnostics, or full analysis specification, so the adjustment cannot be independently reconstructed from the listed summaries.

The pair labels show that the reported ANCOVA comparisons use the active-treatment groups from different paradigms. Their estimates are therefore distinct from the within-paradigm active-versus-placebo contrasts that a reader might expect from the study's objectives. The listed contrast groups and the registry's estimate label should not be conflated: the record gives both, but does not explain their relationship in further detail.

How should a confidence interval be read?

In general, a confidence interval describes the range of values reasonably compatible with the data and the model under the method's assumptions. A wider interval indicates less precision than a narrower interval. For a difference, an interval that includes zero is compatible with no difference as well as with differences in either direction. It does not prove equivalence or establish that every clinically relevant difference has been ruled out.

Five of the six reported comparisons have a confidence-level label of 95. The comparison of Paradigm 1 with Paradigm 4 has a label of 395, although its interval endpoints are listed. The registry record does not clarify whether that label is an error or has another explanation; the interval should not be relabeled by assumption.

What do the p-values mean?

In general, a p-value describes how unusual data at least as incompatible with a specified null model would be if that model and the analysis assumptions were correct. It is not an estimate of effect size and does not express the probability that the null hypothesis is true. The six reported values range from 0.521 to 0.914. Considered alongside the intervals, they do not provide strong evidence of differences among the listed active-treatment paradigms. They also do not show that the groups are equivalent.

Why do group size and analysis population matter?

The endpoint summaries use the safety analysis set with data at both time points. The numbers with endpoint data differ across groups, and the placebo groups have few observations. Unequal or small group sizes can make estimates less precise, especially when variability is substantial. The record gives ranges but not standard errors for these medians, and it does not report a missing-data method or reasons for unavailable observations.

The study enrolled 84, but the endpoint counts are not the enrollment count. The registry also lists adverse-event risk sets that differ in places from the endpoint counts. Each number pertains to its stated analysis population; counts from different outcomes should not be combined.

What do the planning assumptions mean?

General sample-size illustrations use assumptions about the significance level, allocation, and effect to detect. Such planning calculations are not observed power and do not show what power the completed study achieved. The registry describes an illustration based on the observed effect, two-sided significance level 0.05, equal allocation, and a normal approximation, with the target effect expressed as a fraction of the observed effect. The resulting sample-size values are not reported in the registry record. The trial's own sample-size justification and design assumptions are also not reported in the registry record.

10. Analyses Reported by the Sponsor

The registry reports the sponsor's ANCOVA results as six least-squares mean placebo-adjusted differences, with intervals and p-values. The reported comparisons pair the active-treatment arms across Paradigms 1–4. Their point estimates range from -0.09 to 0.39, and all listed intervals span zero. One interval is paired with a confidence-level label of 395 rather than 95; the record does not clarify this label.

A separate recalculated estimate is not reported in the registry record, so there is no numerical recalculation to compare with the sponsor's analysis. The group-level primary summaries are medians and full ranges, whereas ANCOVA produces adjusted model estimates; these quantities answer different statistical questions and are not interchangeable. The record does not flag a discrepancy between a sponsor estimate and a recalculation. The sponsor analysis should therefore be read as the available adjusted analysis, while recognizing that the model details and the meaning of the placebo-adjusted label for active-arm pairs are not fully explained.

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 11 outcome measures and six analyses. The primary outcome is pain-score change, and the listed secondary outcomes include clinician- and patient-reported submental fat ratings, a subject self-rating, submental skin laxity grades, submental fat thickness, and patient-experience questions. The six reported ANCOVA comparisons concern pairs of active-treatment paradigms.

When multiple outcomes or comparisons are examined, the chance of finding at least one apparently notable result can increase. A multiplicity plan specifies whether and how analyses account for that issue, for example through an adjustment procedure or a prespecified hierarchy. Such a plan is not reported in the registry record. The record also does not report whether the six comparisons were prespecified, whether other analyses were conducted, or whether there were interim analyses.

The endpoint population is described as the safety analysis set with available data at baseline and Day 84. This makes availability at both time points part of the stated analysis population, but the record does not explain why observations were unavailable or how missing data were handled. It does not report imputation, sensitivity analyses, or a comparison of participants with and without endpoint data. Consequently, the potential effect of missing observations on the outcome summaries cannot be assessed from the record.

Different analyses have different denominators. The primary endpoint group counts are not the same as all adverse-event risk-set counts, and neither should be treated as a universal study denominator. The record does not give a detailed account of analysis-population definitions beyond the primary endpoint description, nor does it report a participant flow by randomized assignment and follow-up status. These omissions limit evaluation of attrition and of how well each analysis reflects the randomized groups.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

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 list zero affected participants in every treatment group. The risk-set counts for these summaries are 17, 3, 17, 4, 16, 4, 18, and 4 across Paradigms 1 through 4, for deoxycholic acid and placebo respectively. These are group-specific counts, not the primary endpoint counts.

Zero reported serious adverse events in these groups describes what was recorded for the listed risk sets. It does not establish that the risk of a serious event is zero, particularly when the groups are small. The record does not list serious adverse-event terms.

The separate “other adverse events” summaries report all participants in each listed risk set as affected. This category should not be read as synonymous with serious adverse events. Death counts are not reported in the record; their absence from the listed numeric values should not be interpreted as a reported zero. The adverse-event figures alone do not characterize event types, timing, severity beyond the serious-event classification, or causal attribution.

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

The primary endpoint summaries show a median pain-score change of 0 in each of the eight groups between baseline and Day 84. The full ranges show that observed changes varied within some groups. The adjusted comparisons among active-treatment paradigms have estimates close to zero relative to their listed intervals, but those intervals are broad enough to include differences in either direction.

These findings do not demonstrate that the four management paradigms produce identical pain outcomes. Nor do they establish that deoxycholic acid and placebo have the same pain outcomes: the six reported ANCOVA comparisons pair active-treatment groups across paradigms, not active treatment with placebo within each paradigm. The within-group medians and ranges include placebo groups, but they do not replace a direct randomized comparison.

The estimates also do not answer every objective described for the study. The primary endpoint addresses pain-score change, while the stated objectives also concern safety, bruising, swelling or edema, and patient experience. Secondary outcome names are listed, but the corresponding results are not included in the registry record used for this statistical account. Those results are not reported in the registry record.

More generally, a nonsignificant result is not proof of no effect. Confidence intervals communicate precision and include values compatible with more than one interpretation. The small numbers with endpoint data in the placebo groups and the unreported missing-data methods further constrain what can be concluded. The results are best read as a description of the posted endpoint summaries and adjusted comparisons, not as definitive evidence for or against a treatment effect.

14. Why This Trial Matters Statistically

This study is statistically informative because it combines a treatment comparison with different approaches to managing the experience of injections. The four paradigms progressively include measures such as anesthetics, oral agents, and a compression chin strap. That design makes it important to distinguish the effect of the injection assignment from differences associated with the broader management approach.

The primary summaries and adjusted analyses address different questions. Group medians describe recorded changes in each arm, while ANCOVA estimates adjusted contrasts. Here, the reported model comparisons are between active-treatment paradigms, even though the estimates are labeled placebo-adjusted differences. Reading the comparison groups carefully prevents an active-versus-active estimate from being mistaken for an active-versus-placebo result.

The record also illustrates why precision and analysis populations matter. Some endpoint groups, especially placebo groups, have few observations, and the record does not explain missing-data handling. The intervals offer more context than point estimates alone, while the confidence-level label of 395 for one comparison requires caution. Together, these features show how clear reporting of contrasts, model details, denominators, and interval labels is essential for interpreting a clinical trial.

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 registry record leaves several trial-specific questions unresolved. It identifies a randomized, double-blind, parallel-group study but does not report the allocation ratio, randomization procedure, masking implementation, or detailed eligibility criteria. The official title calls the study two-factor, yet the record does not provide a full statistical description of how the factors were modeled.

The primary endpoint is reported as a median and full range, with no confidence interval for the group medians. The endpoint counts vary across groups, and the reasons for unavailable observations and missing-data methods are not reported. The listed adjusted comparisons do not directly compare deoxycholic acid with placebo within a paradigm, and the record does not explain the relationship between the active-arm pairs and the “placebo-adjusted” estimate label.

The model covariates, diagnostics, and analysis specification are not reported. A confidence-level label of 395 appears for one interval, with no clarification. The record also does not report a multiplicity plan, the trial's sample-size justification, or interim-analysis details. Although secondary outcomes are named, their results are not included in the registry record used. These limitations restrict assessment of precision, missingness, model validity, and the broader study objectives.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Patient Experience Study of Deoxycholic Acid Injection — NCT02007434.
• Registry record last updated 2015-07-28; status last verified 2015-07.
• Results first posted 2015-07-03.
• 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

NCT02007434 is a completed phase 3, randomized, double-blind, parallel-group study of deoxycholic acid injections and placebo for moderate or severe submental fullness. The registry lists enrollment of 84 and describes four management paradigms at a single center.

The primary endpoint was change in pain visual analog scale score from baseline to Day 84, summarized by medians and full ranges. Every group's median change was 0. Six reported ANCOVA comparisons pair active-treatment paradigms; their estimates and intervals do not establish equivalence. One interval has a confidence-level label of 395, which is unexplained in the record. The primary endpoint analysis population had available data at both time points, and missing-data handling is not reported.