A Mobile Tai Chi Platform for Fall Prevention and Cognition in Older Adults: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Mobile Tai Chi Platform for Fall Prevention and Cognition in Older Adults (NCT05209464), a na na study. The primary outcome is Protocol Adherence.

2. Clinical Question

The broader study aim was to assess feasibility and acceptability and to explore changes in physical activity, self-efficacy, quality of life, cognitive function, balance, gait, and Tai Chi proficiency. These are exploratory aims described in the registry record; they should not be confused with the primary adherence outcome. The record does not report an observed adherence percentage or the results of those other measures. It describes four remote and/or in-person visits for mobility tests and questionnaires. With a single group and no control comparison, the central question is descriptive: how much of the planned practice participants completed, and what changes were observed during participation. The design cannot by itself separate changes over time from changes attributable to the intervention.

3. Trial Design

This is a completed, single-group study of Tele-Tai Chi in older adults, registered as NCT05209464. The registry lists Spaulding Rehabilitation Hospital as sponsor and an enrollment of 8. The study began on 2022-10-13, has a primary completion date of 2023-06-14, and is listed as completed. The record gives no randomized allocation and lists masking as none. There is no separate control arm, so the study is not a randomized comparison.

The intervention is a simplified Tele-Tai-Chi program delivered via a mobile application for 12 weeks at home. Study participation includes four remote and/or in-person visits at Spaulding Rehabilitation Hospital for mobility tests and questionnaires. The registry describes the study as intended to assess feasibility and acceptability while exploring changes in several clinical and functional measures. The primary outcome is protocol adherence, defined as the percentage of practice sessions completed after 12 weeks.

Enrollment is not the same as the number contributing data to a particular outcome. For the primary outcome, the record says analysis was limited to participants who took part in the intervention and completed both baseline and post-intervention assessments. The number meeting that description is not reported in the registry record. Safety figures list 7 participants at risk for the reported event categories; that figure should not be assumed to be the primary-outcome analysis size.

The registry record does not report a sample-size justification, a detailed statistical analysis plan, or interim analyses. The trial's single-group design can describe adherence and changes over time among participants with measurements, but it cannot estimate a treatment contrast against a concurrent control group. Any interpretation should therefore remain within the limits of a small feasibility-oriented study rather than treating the design as a confirmatory comparison.

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

Analysis population for the primary outcome, as defined in the registry: Data analysis was limited only to subjects who participated in the intervention and completed both baseline and post-intervention assessments.

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 Protocol Adherence, measured over Percentage at post-intervention (after 12 weeks).

The primary endpoint is protocol adherence, measured as the percentage of Tele-Tai-Chi practice sessions completed at post-intervention, after 12 weeks. It is a continuous measure summarized in the registry as a mean with standard deviation. Its focus is whether participants carried out the prescribed practice during the study, rather than whether a clinical condition improved.

Adherence is relevant to feasibility because a home-based program depends on participants being able to engage with it over the intended period. A percentage expresses completion relative to the sessions participants were expected to undertake, while the mean describes the average across the analyzed participants. The standard deviation describes how much individual percentages varied around that average. A mean alone can conceal substantial variation: participants may cluster near the average or have very different completion levels.

The registry record defines the primary-outcome population as participants who took part in the intervention and completed both baseline and post-intervention assessments. It does not report the observed mean, standard deviation, individual distribution, or number contributing to this endpoint. Consequently, the endpoint's definition and intended summary are clear, but the actual level and variability of adherence cannot be described from the registry record. The percentage is a measure of participation in practice sessions, not a direct measure of cognitive, balance, gait, or fall outcomes.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a mean describe?

For a continuous outcome, a mean is the arithmetic average of the recorded values. In this study, the planned primary measure is each participant's percentage of Tele-Tai-Chi practice sessions completed at the post-intervention assessment. A mean across participants would describe the average adherence percentage in the analyzed group. It would not say that every participant had that percentage, nor would it show whether participants had similar or widely varying adherence.

The registry specifies standard deviation as the measure of dispersion. In general, standard deviation describes the spread of observations around their mean, expressed on the outcome's scale. A small spread would indicate that participant values were relatively close to the average; a larger spread would indicate more variability. Neither the mean nor the standard deviation for protocol adherence is reported in the registry record, so the observed average and variability cannot be interpreted.

How does a confidence interval help?

In general, a confidence interval communicates uncertainty around an estimated quantity. For a mean, it can show a range of values compatible with the data and the method used to calculate the interval. Its width depends on factors such as the amount of variability and the number of observations. A narrow interval indicates greater precision under the model's assumptions; a wide interval indicates less precision. A confidence interval is not a guarantee that the true value lies in the displayed range, and its interpretation depends on the statistical procedure.

No confidence interval for the primary adherence outcome is reported in the registry record. Without an estimate and an uncertainty interval, the precision of the adherence result cannot be assessed. In a small feasibility study, uncertainty is especially important: a point estimate alone, even if reported, may not represent the range of plausible values well.

Why does the single-group design matter?

In general, a randomized comparison estimates the difference in outcomes between groups assigned to different conditions. This study has no randomized allocation and no separate control group, so it does not produce that kind of treatment contrast. A within-group change, if reported, would describe how measurements differed over time among observed participants. It would not by itself identify the cause of that change. The registry record does not report a numerical change estimate for the primary endpoint or the other outcomes.

The primary endpoint is adherence at post-intervention rather than a between-visit treatment effect. Its interpretation depends on how practice sessions were defined and recorded. The registry describes the outcome as a percentage of sessions completed, but further operational detail about session tracking is not reported in the registry record. Such detail would help readers assess exactly how the percentage was obtained.

What do the analysis population and missing data mean?

The record says the primary analysis was limited to participants who participated in the intervention and completed both baseline and post-intervention assessments. In general, restricting analysis to participants with complete assessments can make the analyzed group differ from all enrolled participants if completion is related to adherence or outcomes. The degree and direction of any such difference cannot be determined without information on missingness and participant-level results. The record does not report how many participants completed both assessments or how missing values were handled.

Enrollment, the number at risk for safety reporting, and the number included in a particular outcome analysis are distinct quantities. Enrollment is listed as 8, safety reporting uses 7 at risk, and the primary-outcome analysis size is not reported in the registry record. No denominator should be substituted for another without evidence that they refer to the same participants.

How should the planning assumptions be read?

The registry includes planning illustrations based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The illustrations consider detecting a stated fraction of the observed effect. These are hypothetical planning assumptions, not a description of the trial's single-group design, which has no two-arm randomized comparison. They are not the trial's own sample-size justification, which is not reported in the registry record, and they are not observed power. A planning sample size asks how many participants might be needed under stated assumptions for a future comparison; it does not establish what this completed study demonstrated.

In general, power is a design-stage probability of detecting a specified effect under a statistical model if that effect exists. It is not a measure of the probability that a result is true, and it should not be calculated after the fact to summarize a study's findings. Planning illustrations based on an observed effect can be sensitive to how that effect was estimated. In this case, the registry's assumptions should be kept separate from the study's descriptive feasibility aims and from any unreported outcome results.

What role would a statistical test play?

In general, a statistical test evaluates data against a specified null hypothesis using assumptions about the design and distribution. A p-value describes how unusual data at least as extreme as those observed would be if the null model and its assumptions held. It does not measure the size or clinical importance of an effect. The registry record lists no analyses and reports no p-value for the primary outcome. Given the single-group design and the absence of a reported estimate, there is no inferential result to interpret for adherence.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Tele-Tai Chi")
n   <- c(6)
m   <- c(78.6)
sp  <- c(45.1)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Tele-Tai Chi  6  78.600  45.100  31.270  125.930

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 22 outcome measures, while the record lists no statistical analyses. The study description includes a primary adherence measure and several exploratory aims spanning physical activity, self-efficacy, quality of life, cognition, balance, gait, and Tai Chi proficiency. When many outcomes are examined, the chance of at least one apparently unusual result can increase if each is tested separately. General approaches to this issue include defining a primary outcome in advance, adjusting testing procedures, or treating secondary findings as exploratory. The registry record does not report a multiplicity strategy, so it is not possible to determine whether or how multiple testing was addressed.

The primary-outcome population is described as participants who took part in the intervention and completed both baseline and post-intervention assessments. The number meeting this definition is not reported in the registry record. The record also does not report how missing assessments or incomplete practice-session data were handled, whether any imputation was used, or whether sensitivity analyses were performed. These details matter because complete-case results can be affected if participants with missing measurements differ from those with complete data.

Enrollment is listed as 8, and the safety figures list 7 participants at risk. Neither number establishes the denominator for every outcome. With no outcome-analysis counts or missing-data methods reported, the completeness and representativeness of the analyzed data cannot be assessed. The registry record also does not report interim analyses or a detailed statistical plan. These omissions limit evaluation of how outcome selection, missingness, and multiple comparisons may have influenced interpretation.

12. 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 registry reports 0 serious adverse events among 7 participants at risk, 5 participants with other adverse events among 7 at risk, and 0 deaths. These are event-category counts for the Tele-Tai Chi group. The record does not list serious-event terms, and it does not identify the types of the other adverse events in the information available. The term “other adverse events” should therefore be read as a registry category, not as a description of what occurred.

These figures are descriptive and do not provide a comparison with another group. A count of 0 serious adverse events in this group does not establish that serious events are impossible or that the same count would occur in a larger or different population. Likewise, the count of 5 with other events does not indicate their nature, severity, timing, or relationship to participation, because those details are not reported in the registry record.

The safety denominator of 7 should not be confused with the enrollment of 8 or with the unreported primary-outcome analysis size. The record does not explain the difference between enrollment and the number at risk. The counts can be reported as recorded, but the available information does not support additional conclusions about comparative risk or causation.

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

The registry record describes a completed study of a 12-week mobile Tele-Tai-Chi program in older adults, with protocol adherence designated as the primary endpoint. The study's aims also include feasibility and acceptability and exploration of several functional and cognitive measures. However, the record does not report the observed adherence percentage, its standard deviation, or numerical results for the other outcomes. The design and outcome definitions can be described, but the magnitude of the observed outcomes cannot be assessed from the registry record.

The single-group structure means that there is no control group against which to compare participants' outcomes. Even if changes from baseline to post-intervention were reported, such changes would be descriptions of the participating group over time rather than randomized treatment effects. In general, uncontrolled changes may have multiple explanations, and this design does not separate them. The registry record does not report an estimate of change that could be evaluated on its own terms.

The safety record reports no serious adverse events and no deaths among 7 participants at risk, with 5 participants reported as having other adverse events. These figures are useful as a description of the recorded safety categories in this group. The event details are not reported in the available record, and no comparator is available for a comparative safety estimate.

Accordingly, the record does not establish the level of adherence achieved, the degree of variability between participants, or the size of any change in clinical or functional measures. It also does not establish that an outcome would differ from what would have occurred without the program. The study can be read as a small, single-group investigation with feasibility-oriented aims and limited reported numerical outcomes, not as a controlled test of effectiveness.

14. Why This Trial Matters Statistically

Statistically, a feasibility study asks questions that precede a definitive comparison: whether participants can engage with an intervention and whether key procedures and measurements can be carried out. The primary endpoint, the percentage of practice sessions completed after 12 weeks, is directly relevant to participation in a home-based program. The registry also identifies acceptability as an aim and describes four remote and/or in-person visits for assessments. These features make adherence and the conduct of assessments central to understanding the study's purpose.

At the same time, numerical results are essential for evaluating feasibility. An adherence mean, its variability, the number contributing data, and information about missing assessments would help readers understand participation and the reliability of the estimate. Those primary-outcome results are not reported in the registry record. The listed enrollment and safety counts do not substitute for outcome-specific denominators or estimates.

The single-group design is also an important statistical boundary. It can support description of participants' experience and measurements, but without a concurrent comparator it cannot isolate an intervention effect from other explanations for change. This distinction helps keep exploratory observations separate from comparative evidence. The registry's planning assumptions describe hypothetical sample-size calculations under a two-arm framework; they do not change the study's actual single-group structure or supply missing outcome results.

The record therefore matters as an example of why design, outcome definition, analysis population, and result reporting must be considered together. A clearly defined adherence endpoint can orient interpretation, but without its observed value and uncertainty, the primary statistical finding remains unavailable. Reporting those elements would be necessary for readers to judge the precision and practical interpretation of the study's feasibility observations.

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 study enrolled 8 participants and used a single-group design with no randomized allocation or separate control group. This limits the scope of inference: outcomes can be described in the participating group, but the design does not provide a controlled estimate of the effect of Tele-Tai Chi. The registry record does not report demographic or other participant characteristics that would clarify how closely the participants represent older adults beyond the study description.

The primary outcome is defined as the percentage of practice sessions completed after 12 weeks, but the observed value, standard deviation, and number included in its analysis are not reported in the registry record. The record says primary analysis was limited to participants who participated in the intervention and completed baseline and post-intervention assessments, but does not say how many met those criteria. The safety denominator is 7, while enrollment is 8; the reason for that difference is not reported in the registry record.

The registry lists 22 outcome measures and no statistical analyses. It does not report how multiplicity was handled, how missing data were treated, whether sensitivity analyses were conducted, or whether interim analyses occurred. A detailed statistical plan and sample-size justification are also not reported in the registry record. These gaps prevent assessment of analysis choices, outcome completeness, and precision.

Safety reporting is limited to the recorded counts: the types of other adverse events are not specified, and serious-event terms are not listed. The record does not provide comparative safety information. Finally, the registry's planning assumptions are hypothetical two-arm calculations and do not represent the actual single-group comparison structure. Together, these limitations mean that the available record is insufficient for quantitative interpretation of adherence or clinical changes.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: A Mobile Tai Chi Platform for Fall Prevention and Cognition in Older Adults — NCT05209464.
• Registry record last updated 2024-08-28; status last verified 2024-08.
• Results first posted 2024-08-28.
• 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

NCT05209464 is a completed, single-group study sponsored by Spaulding Rehabilitation Hospital. It enrolled 8 older adults and evaluated a simplified, home-based Tele-Tai-Chi program delivered through a mobile application over 12 weeks. The registry lists no randomized allocation and no masking.

The primary endpoint is protocol adherence, defined as the percentage of practice sessions completed at post-intervention. The primary-outcome analysis population is described as participants who took part in the intervention and completed both baseline and post-intervention assessments. The observed adherence result and analysis size are not reported in the registry record. The study also aimed to assess feasibility and acceptability and explore physical activity, self-efficacy, quality of life, cognitive function, balance, gait, and Tai Chi proficiency.

Safety figures report 0 serious adverse events, 5 participants with other adverse events, and 0 deaths among 7 participants at risk. The registry lists 22 outcome measures and no statistical analyses. Its record supports description of the design and reported safety counts, but does not provide numerical primary-outcome or other outcome results.