The Project Wellness Pilot Feasibility Randomized Controlled Trial: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Project Wellness Pilot Feasibility Randomized Controlled Trial (NCT04209348), a randomized na study. The primary outcome is Change in Self-reported Physical Activity (Assessed by Pregnancy Physical Activity Questionnaire) From Baseline to Follow-up.

2. Clinical Question

The trial description also identifies maternal glycemic profile in the third trimester and infant size and anthropometric measurements after birth as outcomes of interest. The stated hypotheses anticipated increased physical activity and improved maternal and infant measures with the physical activity intervention, and an association between maternal glycemic profile and infant anthropometric measurements. Those hypotheses are not themselves results. The posted primary outcome concerns self-reported activity, and the registry record does not give a result for the hypothesized association.

3. Trial Design

Project Wellness is described as a pilot feasibility randomized controlled trial. The registry record lists randomized allocation, double masking, and a parallel design. It reports enrollment of 20 and a completed status. The recorded start date is 2020-08-21, and the primary completion date is 2021-09-21. Phase is listed as not applicable.

The two intervention groups were Physical Activity Intervention and Wellness Education. The former used walking or stepping in place as its behavioral focus, with a goal of at least 30 minutes per day. The latter delivered wellness education, including information about immunizations and postpartum contraceptive options. The registry record does not describe who was masked, how masking was maintained, or whether participants could identify their intervention from its content.

The sponsor was The University of Tennessee, Knoxville. The trial description places the study at the University of Tennessee Medical Center Knoxville and identifies women at risk for or diagnosed with gestational diabetes as its intended population. The registry record does not report additional details about recruitment, eligibility, or the allocation procedure.

Although the record labels the trial a feasibility pilot, it does not report a feasibility outcome among the posted results described for the primary endpoint. Nor does the record explain the basis for enrollment or give a statistical justification for the planned enrollment. Those design details are not reported in the registry record. The reported primary result is based on 9 participants per group, rather than the enrollment figure, and the record does not explain the difference between those figures or give further details about the analysis population.

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:

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: The trial initially launched in December 2019 but closed in March 2020 due to the COVID-19 pandemic. It re-launched in August 2020. The flow chart with eligibility and recruitment metrics is therefore presented for December 2020 through September 2021, the period unaffected by research restrictions.

6. Primary Endpoint

The registry lists the primary outcome as Change in Self-reported Physical Activity (Assessed by Pregnancy Physical Activity Questionnaire) From Baseline to Follow-up, measured over approximately 6 weeks.

The primary endpoint is change in self-reported physical activity from baseline to follow-up, approximately 6 weeks later. It uses the Pregnancy Physical Activity Questionnaire to assess moderate to vigorous intensity walking or running in the sports and exercise domain. Change is defined as the follow-up measure minus the baseline measure, and the unit is MET hours per week.

This endpoint focuses on the type of activity targeted by the behavioral intervention. In general, measuring change allows a study to describe how a participant's reported activity at follow-up compares with their own baseline measurement. The questionnaire-based measure captures reported activity, not a direct measurement of movement. The registry record does not report an objective activity measure or details about how questionnaire responses were collected.

The primary endpoint is distinct from the maternal glycemic profile and infant anthropometric outcomes described as other aims of the trial. The posted result for this endpoint is a mean change for each group with a 95% confidence interval. The registry record does not report a direct two-arm estimate for the difference in mean change, so the group-specific summaries alone do not quantify the randomized contrast.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record describes a randomized, double-masked, parallel-group pilot feasibility trial. The posted primary endpoint is continuous and is summarized as a mean with a 95% confidence interval. The interpretation below separates what those summaries describe from what would be needed to answer a direct randomized comparison question.

What does a mean change describe?

In general, a mean is a measure of the central value of observations. For this endpoint, the observations are changes in questionnaire-assessed activity from baseline to follow-up, expressed in MET hours per week. A positive mean indicates that the average reported follow-up measure was higher than the average baseline measure under the stated change definition; a negative mean indicates that the average follow-up measure was lower. These descriptions refer to group averages and do not imply that every participant changed in the same direction.

The registry record reports mean change separately for Physical Activity Intervention and Wellness Education. Such within-group estimates describe each group's observed change. In a randomized trial, the central treatment comparison is typically a contrast between groups, because that contrast directly compares outcomes under the allocated interventions. The record says a two-arm comparison value was missing or not estimable for this continuous endpoint. It therefore does not provide the contrast or its uncertainty. The group-specific means cannot be treated as though they were that contrast.

How should the confidence intervals be read?

In general, a confidence interval represents uncertainty in an estimate under the statistical procedure used. A 95% confidence interval is constructed by a method designed to cover the underlying quantity at the stated rate over repeated use of that method, when its assumptions hold. It is not an interval containing 95% of individual outcomes, and it is not a guarantee that the true value lies within the particular interval reported.

The posted intervals accompany group means, so they express uncertainty about those group-specific means. They are not confidence intervals for the difference between the intervention groups. The Physical Activity Intervention interval extends across zero, while the Wellness Education interval is below zero. This describes each interval relative to no average change; it does not establish whether the groups differ. A direct comparison would require an estimate of the between-group contrast and its uncertainty, neither of which is reported in the registry record.

What does randomization contribute?

In general, random allocation is intended to create groups that are comparable on average at the start of a trial, including with respect to factors that are measured and factors that are not. It supports causal interpretation of a properly analyzed between-group comparison, subject to issues such as adherence, missing outcome data, and the analysis population. Randomization does not make separate within-group changes a substitute for the randomized contrast.

The record identifies allocation as randomized and the design as parallel. It does not report how the allocation sequence was generated or concealed, and it does not explain who was masked. The intervention descriptions differ in content, but the registry record does not specify whether masking was feasible for participants, intervention staff, or outcome assessors. These implementation details are not reported in the registry record.

What is the role of the planning illustrations?

General sample-size calculations use assumptions about the effect to detect, variability, significance level, allocation, and statistical method. The planning assumptions associated with this trial use a two-sided significance level of 0.05, equal allocation, a normal approximation, and fractions of the observed effect. They are planning illustrations based on the observed effect, not the trial's original design calculation and not observed power. They should not be interpreted as evidence that the trial had a particular probability of detecting an effect. The registry record does not report the trial's own sample-size justification.

For continuous endpoints, a planning illustration expressed as participants per arm is conditional on its assumptions. In general, choosing a smaller effect to detect requires more information than planning around a larger effect, all else being equal. This general relationship does not identify which assumptions are appropriate for future studies. The registry record does not report an external target effect, a variance assumption, or a rationale for the planning fractions. Any planning count should therefore be treated as an illustration rather than a design recommendation.

What cannot be recovered from these summaries?

Group means and confidence intervals do not reveal the participant-level distribution, whether changes were skewed, or how missing observations were handled. The registry record does not report a model specification, covariate adjustment, a method for missing data, or an analysis population definition. Those details matter when assessing the precision and interpretation of an estimate. The registry record also does not report a two-arm estimate or a statistical analysis plan for this endpoint.

The trial description includes several outcomes and hypotheses, but the primary outcome summary alone does not show results for maternal glycemic profile, neonatal anthropometry, or the proposed association between maternal and infant measures. Statistical interpretation should remain tied to the endpoint actually summarized. General principles about confidence intervals and randomized comparisons explain how to read the report; they do not fill in analyses or results that are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists four outcome measures and names two posted secondary outcomes: Neonatal Subscapular Skinfolds and Birthweight-for-gestational-age Z-score. It reports no analysis entries. The primary endpoint is change in self-reported physical activity. The available record does not state how many hypotheses were treated as confirmatory, whether any outcomes were prioritized beyond the listed primary endpoint, or whether a multiplicity adjustment was planned or used.

In general, evaluating several outcomes or several analyses can increase the chance of finding at least one apparently unusual result by chance. Statistical methods can address multiplicity, but the appropriate approach depends on the prespecified questions and analysis plan. No multiplicity strategy is reported in the registry record. The named secondary outcomes should therefore be understood as listed outcomes, not as evidence that a particular family-wise or other error-rate procedure was used.

The registry record provides group-specific primary outcome summaries, but says values were missing or not estimable for a two-arm comparison of this continuous endpoint. It does not report the reasons that the comparison was unavailable. The endpoint results list 9 participants per group, while the overall enrollment is 20; the record does not explain the difference. It does not report missing-data counts, reasons for missingness, imputation procedures, or sensitivity analyses. It also does not define an intention-to-treat, per-protocol, or other analysis population.

In general, missing outcome information can affect both the representativeness and precision of a result, and the effect depends on why the information is missing and how the analysis handles it. Without the analysis population and missing-data methods, the registry record does not allow those issues to be evaluated for this endpoint. These reporting gaps do not establish that a particular method was or was not used; the details are 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 5% reporting threshold.

The registry record lists 10 participants at risk for serious adverse events in each group and reports 0 serious adverse events in each. It also lists 10 participants at risk for other adverse events in each group and reports 0 other adverse events in each. Deaths are recorded as 0 in both groups, and no top serious adverse event terms are listed.

These figures describe what was recorded in the registry. A count of zero means no events in that category were reported for the listed group; it does not prove that an event is impossible or that the interventions have no risks. With the small groups described in the record, absence of a reported event also cannot establish how frequently an event might occur in a larger population.

The safety figures should not be confused with the primary endpoint analysis. The adverse-event groups list 10 at risk per group, while the primary endpoint results report 9 participants per group; the registry record does not explain the difference. It also does not provide event definitions, collection procedures, exposure duration, or additional detail about how adverse events were monitored. The counts therefore support only a description of the reported registry figures, not a broader safety conclusion.

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

The posted result describes mean change in self-reported physical activity over approximately 6 weeks for each intervention group. The physical activity group mean was 0.22 MET hours per week, with a 95% confidence interval from -0.41 to 0.84. The wellness education group mean was -0.7 MET hours per week, with a 95% confidence interval from -1.31 to -0.1. The registry record does not report the direct between-group estimate for this endpoint.

That missing contrast is important to the interpretation. The purpose of randomization is to support comparison between allocated groups, but the posted group-specific changes do not quantify that comparison. They do not establish that the interventions differed, and they do not establish that they were the same. They also do not establish the effect of either intervention relative to no intervention, because Wellness Education was an active comparator.

The endpoint is self-reported walking or running in the sports and exercise domain. It does not measure every type of physical activity, and the registry record does not report an objective activity measure. A group mean does not describe how much participants varied or whether individual experiences were similar. The confidence intervals characterize uncertainty around the group means, not the range of individual responses and not uncertainty around a randomized contrast.

The study is labeled a pilot feasibility trial, and its description includes maternal glycemic profile and infant anthropometric measurements as additional aims. The primary endpoint summary cannot establish results for those outcomes or for the hypothesized association between maternal glycemic profile and infant measurements. The registry record names secondary outcomes, but numerical results for them are not reported in the registry record for interpretation.

The appropriate conclusion is limited to the registry's reported group-specific summaries and safety counts. The record does not report enough detail to determine why a two-arm estimate was unavailable, how missing data were handled, or how the reported endpoint participants relate to overall enrollment. The posted data therefore describe the measured result but do not provide a precise randomized estimate of the intervention contrast.

13. Why This Trial Matters Statistically

This trial illustrates why a randomized trial's primary question and its reported statistic need to be distinguished. A mean change within each group describes change over time in that group. The between-group contrast addresses whether the changes differ by randomized assignment. The registry record reports the former but not the latter for the primary continuous endpoint. Recognizing that distinction prevents group-specific summaries from being mistaken for a direct treatment comparison.

The record also gives a useful example of reading confidence intervals in context. Each interval is attached to a particular group mean. Even when an interval can be read relative to zero change, that does not answer whether the randomized groups differ. The precision of the between-group question cannot be judged from the reported group intervals alone, especially when the registry says a two-arm comparison value was missing or not estimable.

Because the study is a pilot feasibility randomized trial, its interpretation should also distinguish feasibility aims from estimates of intervention effects. The record describes behavioral and wellness interventions and states hypotheses about activity, maternal glycemic profile, and infant measurements. The posted primary endpoint offers information about reported activity change, but the record does not provide feasibility results or numerical results for the other stated aims in the registry record. A label of pilot feasibility does not by itself specify what feasibility criteria were assessed.

Finally, the difference between overall enrollment and the group sizes reported for the primary outcome, along with the absence of reported missing-data methods and a direct comparison estimate, highlights the value of transparent analysis reporting. These details affect how readers assess precision and generalizability. The record is informative about the design and the reported summaries, while leaving important analysis details not reported in the registry record.

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 primary result is limited to a self-reported activity measure within the sports and exercise domain. The registry record does not provide an objective measure of physical activity or additional details about questionnaire administration. The endpoint therefore represents the specified questionnaire response rather than a comprehensive assessment of all activity.

The registry record gives separate mean changes and confidence intervals but no two-arm comparison estimate, stating that values were missing or not estimable for a two-arm comparison. It does not explain why that estimate was unavailable. As a result, the posted primary endpoint does not directly quantify the randomized contrast. The record also does not report a p-value for that comparison.

Overall enrollment is listed as 20, while the primary endpoint summaries report 9 participants per group. The registry record does not explain this difference or state the analysis population. It does not report missing outcome counts, reasons for missingness, methods for handling missing data, or sensitivity analyses. This prevents a fuller assessment of how the available endpoint summaries relate to enrolled participants.

Although the trial is labeled a pilot feasibility study, feasibility measures or criteria are not described among the available results. The record also does not provide numerical results for the maternal glycemic profile, infant anthropometric measures, or the stated association between maternal and infant measures. Two secondary outcomes are named, but their values are not reported in the registry record for interpretation.

Further design and analysis details are not reported in the registry record, including the sample-size justification, allocation sequence procedures, who was masked, and the statistical analysis plan. The record lists randomized allocation, double masking, and a parallel design, but those labels do not supply the missing implementation details. These reporting limitations constrain interpretation of precision, analysis choices, and how broadly the results may apply.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: The Project Wellness Pilot Feasibility Randomized Controlled Trial — NCT04209348.
• Registry record last updated 2024-02-12; status last verified 2024-01.
• Results first posted 2024-02-12.
• 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 NCT04209348, Project Wellness: A Pilot Feasibility Randomized Controlled Trial, as a completed randomized, double-masked, parallel study sponsored by The University of Tennessee, Knoxville. Enrollment was 20. The recorded start date was 2020-08-21, and the primary completion date was 2021-09-21. The intended population was women at risk for or diagnosed with gestational diabetes at the University of Tennessee Medical Center Knoxville.

The interventions were Physical Activity Intervention, focused on walking or stepping in place, and Wellness Education, focused on maternal and infant wellness information. The primary endpoint was change in questionnaire-assessed moderate to vigorous walking or running activity from baseline to follow-up, approximately 6 weeks later. Results are reported as a mean and 95% confidence interval for each group, but the registry record does not report a two-arm comparison estimate.

The registry lists four outcome measures, two named secondary outcomes, and no analysis entries. Serious adverse events, other adverse events, and deaths are recorded as 0 in each group. Further details about the analysis population, missing data, and statistical plan are not reported in the registry record.