Personalized Lifestyle Intervention and Weight Control: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Personalized Lifestyle Intervention and Weight Control (NCT04079972), a randomized na study. The primary outcome is Body Weight (kg).

2. Clinical Question

3. Trial Design

This is a randomized, parallel-group behavioral trial. The registry lists the allocation as randomized and masking as none. Thus, the assigned approaches were compared between groups rather than by switching participants through both approaches, and masking is not reported as part of the design. The record lists enrollment as 53. It does not report the method used to generate or conceal the allocation sequence, nor does it provide enough information to infer how assignment was carried out.

The intervention was disclosure of obesity-related genetic risk with tailored lifestyle recommendations. Participants received test results related to FTO, MC4R, and BDNF and recommendations tailored to genotype. The comparison intervention disclosed non-obesity-related genetic traits only. Its description says participants did not receive obesity- or metabolism-related genetic information or tailored lifestyle recommendations during the comparison. Both interventions are classified as behavioral.

The trial is listed as completed. Its start date is 2019-06-11 and its primary completion date is 2020-11-02. The phase is listed as NA. The condition is weight loss. The sponsor is NaNa Keum. The registry’s brief summary states that the study aimed to investigate whether tailored lifestyle consultation through SNP testing leads to more effective weight loss among people with overweight or obesity than general lifestyle guidance.

The primary endpoint is body-weight change from baseline at about 5 months after randomization and at study completion, approximately 17 months. Secondary outcomes include body fat mass, body fat percentage, and skeletal muscle mass. The registry record does not report the number of participants analyzed for each outcome, the statistical model, or the detailed analysis plan. The difference between the number who started and the number who completed is noted, but the corresponding analysis-population details are not reported.

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.

About 5 months after randomization

About 17 months after randomization

Analysis population for the primary outcome, as defined in the registry: number of started population differs from completed population

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 Body Weight (kg), measured over About 5 months after randomization and at study completion (~17 months).

The primary endpoint is mean body-weight change, measured in kilograms. Change is defined as the later value minus the baseline value: one assessment is about 5 months after randomization, and another is at study completion, approximately 17 months. Under this definition, a positive value represents an increase from baseline and a negative value represents a decrease. The endpoint therefore describes change over time, not simply the weight measured at a follow-up visit.

Body weight is a continuous measure, so the mean summarizes the group’s average change while the standard deviation describes the spread of individual changes around that mean. Comparing average changes between randomized groups can address whether the groups’ outcomes differed on average. Interpretation still depends on the size and uncertainty of the estimated difference, the number of participants contributing data, and the analysis approach. Those numerical results and details are not reported in the registry record.

Using change from baseline gives a direct description of how the measured value moved during follow-up. It does not, by itself, resolve possible issues such as missing follow-up measurements or differences in baseline values. Those questions depend on the analysis plan and the available participant-level data. The registry record notes that the number who started differs from the number who completed, but does not report how that difference was handled in the endpoint analysis.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical methods help turn measurements into comparisons while making explicit the assumptions and uncertainty involved. The registry record identifies a continuous primary outcome summarized as a mean with standard deviation, but does not report the statistical model, the inferential procedure, or numerical endpoint analyses. The explanations below are general and should not be read as a description of methods confirmed for this trial.

What does a mean change describe?

For a continuous outcome, each participant’s change is the follow-up measurement minus the baseline measurement. Averaging those changes gives the group mean change. In this study’s endpoint definition, a negative change represents a decrease in body weight and a positive change represents an increase. The mean gives a concise group-level summary, but it does not show the distribution of individual changes or whether most participants changed in a similar way.

The standard deviation is a measure of variability among the individual values around the mean. It is not the uncertainty of the mean itself, and it should not be interpreted as a range containing every participant’s value. A group can have a particular mean change while individual outcomes vary considerably. Because no means or standard deviations are reported in the registry record, the amount of observed variation cannot be assessed.

How would a between-group comparison be interpreted?

A randomized comparison commonly focuses on the difference in average outcome between assigned groups. For a change outcome, that contrast would compare the groups’ mean changes. The contrast’s sign depends on the order in which groups are subtracted, so a report should state the comparison clearly. The registry record does not provide a numerical contrast or specify its direction convention.

A confidence interval expresses uncertainty around an estimated contrast. In general, it gives a range of values compatible with the observed data under a specified statistical model and its assumptions. It is not a guarantee that the true effect lies in that particular interval, nor does it alone establish practical importance. Its width is affected by factors such as variability and the amount of informative data. No confidence interval is reported for the primary outcome in the registry record.

A p-value, when reported, describes how incompatible the observed data are with a specified null hypothesis under the assumptions of the test. It does not measure the probability that the null hypothesis is true, and it does not quantify the size or importance of an effect. The registry record does not report primary-outcome p-values or identify a testing procedure.

Why do the two follow-up times matter?

The primary outcome description specifies change at about 5 months after randomization and again at study completion, approximately 17 months. These are separate follow-up assessments, not repeated versions of one single comparison. In general, an earlier result describes change by an earlier point in follow-up, while a later result describes change over a longer interval. The two estimates can differ, and the record does not identify one as the sole primary time point or provide a rule for prioritizing them.

When an outcome is measured at multiple times, the analysis must account for the question being asked and, where relevant, the dependence between measurements from the same participant. A model that uses repeated measurements may handle that dependence differently from separate analyses at each time. The registry record does not report whether repeated-measures methods, separate comparisons, or another approach was used. No particular approach should be assumed.

What is the role of randomization and masking?

Randomization is a design method intended to balance, on average, measured and unmeasured baseline characteristics across assigned groups. It supports causal interpretation when the trial is implemented and analyzed appropriately, but it does not prevent chance imbalances, missing outcome data, or biases arising after assignment. The registry identifies the allocation as randomized but does not describe the sequence-generation or concealment procedures.

Masking is listed as none. In general, when participants or study personnel know which intervention is assigned, expectations may influence behavior, reporting, or measurement. The possible relevance depends on the outcome and on who collects or analyzes it. The registry record does not provide further detail about which individuals knew assignments or how outcome measurement was conducted.

What do planning illustrations mean?

Sample-size calculations are planning tools. They relate a target effect, variability assumptions, significance level, allocation, and desired power to a hypothetical amount of information needed for a future study. They are not observed trial outcomes. The registry describes a planning illustration based on a fraction of the observed effect, using a two-sided significance level of 0.05, equal allocation, and a normal approximation. It specifies that non-time-to-event illustrations are expressed as participants per arm for 80% power or other listed power targets, while time-to-event illustrations use a total event count.

Those assumptions do not establish that the original trial used them. The registry record explicitly characterizes the calculation as an illustration, not the trial’s own design. It does not report the numerical planning results in the information available for this interpretation. An illustration based on an observed effect can also be sensitive to how precisely that effect was estimated; it should not be described as observed power. No sample-size justification or interim-analysis plan is reported in the registry record.

Why does over-dispersion matter in general?

Over-dispersion is a general issue for some statistical models when observed variability is greater than the model assumes. If ignored, uncertainty may be understated and statistical conclusions may be too confident. This is not a claim that over-dispersion applies to this trial: the primary endpoint is continuous, and the registry record does not report a model or an over-dispersion assessment. The concept is included to clarify why analysts check whether model assumptions match the data.

10. Multiplicity, Missing Data and Analysis Populations

The primary outcome is described at more than one follow-up time: about 5 months after randomization and at study completion, approximately 17 months. Looking at multiple time points can create multiple opportunities to identify a difference. In general, a prespecified analysis hierarchy or adjustment can help control the chance of false-positive findings across multiple tests. The registry record does not report whether a multiplicity strategy was planned or used, nor does it identify a single time point as the definitive comparison.

The record lists body fat mass, body fat percentage, and skeletal muscle mass as secondary outcomes. Testing multiple outcomes raises related interpretation questions: the more comparisons considered, the more important it is to distinguish prespecified confirmatory questions from exploratory ones. The registry record does not report an analysis plan or multiplicity adjustment for these secondary outcomes. Their numerical results are not reported in the registry record.

Missing-data handling is also important. The primary outcome description notes that the number who started differs from the number who completed. This signals a difference in participation over the study, but the registry record does not give the number contributing data at each assessment, the reasons for non-completion, or the method used to handle missing measurements. It is therefore not possible to determine whether the endpoint comparison used all randomized participants, only participants with observed measurements, or another analysis population.

In general, analyses based only on observed follow-up measurements can be biased if the likelihood of having a measurement is related to outcome or treatment assignment. Methods that address missing data require assumptions, and sensitivity analyses can help assess how conclusions change under alternative assumptions. Whether any such methods or sensitivity analyses were used is not reported in the registry record.

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.

The registry reports serious adverse event counts separately for the two groups. In the group receiving obesity-related genetic risk disclosure with tailored lifestyle recommendations, 27 were listed as at risk for serious adverse events and 0 as affected. In the group receiving non-obesity-related genetic traits only, 26 were listed as at risk and 0 as affected. The record also lists 0 deaths in each group.

For other adverse events, the record lists 27 at risk and 0 affected in the tailored-recommendation group, and 26 at risk and 0 affected in the comparison group. These are the registry’s reported counts, not evidence that every possible adverse event was actively assessed in the same way or that no unreported event occurred. The record’s serious-event terms list is empty.

At-risk counts describe the groups used in the adverse-event fields; they should not be treated as proof that every participant completed every safety assessment. The record does not explain how these counts relate to the number who started or completed the study, or provide event definitions, collection procedures, or follow-up detail. With 0 affected recorded in each group, the registry provides no between-group event estimate or uncertainty interval. The counts should be read as the safety information reported in the registry, not as a definitive comparison of risk.

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

The registry record describes a randomized comparison of two approaches to genetic information disclosure and lifestyle guidance. Its central outcome is mean body-weight change from baseline, with assessments about 5 months after randomization and at study completion, approximately 17 months. The record also lists body fat mass, body fat percentage, and skeletal muscle mass as secondary outcomes. These details define the study question and the measures selected to address it.

They do not provide the numerical results needed to judge the size or precision of the group comparison. Group means, variability, estimated differences, confidence intervals, and p-values are not reported in the registry record. The record lists 0 analyses and notes that the primary outcome has multiple time points rather than one reduced comparison. Consequently, the record alone does not establish whether the groups differed, by how much, or how uncertain an estimate would be.

The study’s aim should not be confused with a finding. A trial can be designed to test whether an approach changes an outcome without the registry record containing the analysis that answers that question. Likewise, a planning illustration based on an observed effect is not a trial result and is not observed power. The assumptions described for that illustration do not establish the original design rationale.

The safety fields report 0 serious adverse events and 0 deaths in each group, along with 0 other adverse events affected in each group. These entries describe what the registry reports. They do not establish that no adverse event occurred outside the reported fields, and they do not provide an uncertainty estimate for comparing safety between groups.

Overall, the registry record is informative about the intervention contrast, endpoint definition, follow-up schedule, and selected safety counts. It is not sufficient for estimating the outcome effect or assessing its statistical precision. Numerical efficacy results, detailed missing-data handling, the analysis population, and the statistical plan are not reported in the registry record.

13. Why This Trial Matters Statistically

This trial raises a statistical question about how to evaluate an intervention that combines personalized genetic risk information with tailored lifestyle recommendations. The comparison is not simply between receiving and not receiving genetic information: the groups received different kinds of disclosure, and only one group received obesity-related results and tailored recommendations during the comparison. That distinction is central when defining what a group contrast would represent.

The endpoint is a continuous measure expressed as change from baseline, assessed at two follow-up points. This makes it important to state which time point a result addresses and how repeated or multiple comparisons were handled. An estimate at about 5 months and one at study completion, approximately 17 months, answer questions about different follow-up periods. The registry record does not report a statistical plan explaining how these assessments were prioritized or analyzed.

The record also illustrates why outcome definitions and numerical results need to be considered together. Knowing that body weight was measured in kilograms and that negative change indicates a decrease clarifies the scale and direction of the outcome. It does not show the observed group changes or the uncertainty around them. Without those estimates, readers cannot judge the magnitude of any contrast or distinguish a precise estimate from one with substantial uncertainty.

Finally, the record notes that the number who started differs from the number who completed. This makes reporting of participant flow, measurement availability, and missing-data methods particularly relevant to interpretation. Those details, along with the analysis population and numerical outcome results, are not reported in the registry record. The design and outcome definitions are therefore useful for understanding the intended question, while the available results are insufficient to answer it statistically.

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 for interpreting this trial from the registry record is the absence of numerical primary-outcome results. Although body-weight change is defined at two follow-up points, the record does not report group means, standard deviations, between-group estimates, confidence intervals, or p-values. The record lists 0 analyses and indicates that the outcome includes multiple time points without a single reduced comparison.

The record also notes that the number who started differs from the number who completed. It does not report how many participants contributed measurements at either follow-up, why some did not complete, or how missing outcomes were handled. The analysis population and any sensitivity analyses are not reported in the registry record. These omissions prevent assessment of how incomplete follow-up may affect the comparison.

The design is listed as randomized and unmasked, but the registry does not provide the sequence-generation or allocation-concealment methods, the roles of people who knew assignments, or details of outcome measurement. The trial’s statistical analysis plan, sample-size justification, and interim-analysis approach are also not reported in the registry record. The planning assumptions described are characterized as an illustration rather than the trial’s own design.

The listed enrollment is 53, but the registry information does not give baseline characteristics or outcome-specific analysis counts. The available arm descriptions are incomplete, and the registry record does not provide full counseling materials or enough detail to assess how consistently the interventions were delivered. Secondary outcomes are named, but their numerical findings and analysis methods are not reported in the registry record. Safety counts are presented, but event definitions and collection details are not reported.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Personalized Lifestyle Intervention and Weight Control — NCT04079972.
• Registry record last updated 2026-01-06; status last verified 2025-10.
• Results first posted 2025-10-06.
• 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

NCT04079972, titled Personalized Lifestyle Intervention and Weight Control, is listed as a completed randomized, parallel behavioral trial with no masking. The registry lists enrollment as 53, the condition as weight loss, and the phase as NA. The trial started on 2019-06-11 and has a primary completion date of 2020-11-02.

The intervention disclosed obesity-related genetic risk with tailored lifestyle recommendations; the comparison disclosed non-obesity-related genetic traits only. The primary outcome is mean body-weight change in kilograms from baseline, assessed about 5 months after randomization and at study completion, approximately 17 months. Secondary outcomes are body fat mass, body fat percentage, and skeletal muscle mass.

The registry record lists 0 analyses and does not report numerical outcome estimates, statistical uncertainty, or detailed methods for missing data and analysis populations. It records 0 serious adverse events and 0 deaths in each group. The available record defines the study question and outcome schedule but does not provide enough numerical results to estimate the intervention contrast.