On the Move: Optimizing Participation in Group Exercise: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for On the Move: Optimizing Participation in Group Exercise (NCT01986647), a randomized na study. The primary outcome is Change in Self-reported Overall Function From Baseline to 12 Weeks.

2. Clinical Question

3. Trial Design

The registry identifies this as a randomized, single-masked, parallel trial. The record also identifies the design as cluster-randomized. That distinction matters: in a cluster-randomized study, assignment occurs by groups rather than by treating every participant as an independently randomized unit. The registry summary describes participants in independent living facilities and senior high rises, and people living in the community who attended senior community centers. It refers to 32 different facilities or settings.

The four intervention descriptions combine two exercise programs with two delivery arrangements. On the Move was delivered by an exercise leader or staff activity personnel; the standard seated program was delivered by either type of provider. The registry describes both programs as taking place 2 times per week for 12 weeks, with sessions lasting approximately 1 hour. The On the Move sessions focused on timing and coordination exercises; the standard sessions were impairment-based seated group exercise.

Enrollment is listed as 424. The brief summary describes a plan involving 400 community-dwelling older adults, so the planned figure and the registry enrollment figure are not the same. The record does not explain that difference. The study status is completed. The recorded start is 2013-12 and primary completion is 2016-05. Phase is listed as NA, which is not a drug-development phase description.

The primary endpoint was change in Late Life Function and Disability Index overall function from baseline to 12 weeks. The record lists 16 outcome measures and 16 analyses. Details such as the randomization procedure, concealment, and the exact analysis population 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.

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.

6. Primary Endpoint

The registry lists the primary outcome as Change in Self-reported Overall Function From Baseline to 12 Weeks, measured over baseline and 12 weeks.

The primary endpoint is change in self-reported overall function from baseline to 12 weeks, measured with the Late Life Function and Disability Index (LLFDI) overall function score. The registry describes the score as ranging from 0-100, with higher scores representing better function. The unit is listed as units on a scale, and the endpoint is characterized as a mean of a continuous measure.

Self-reported function captures participants’ perceptions of how well they can carry out activities. It is relevant to a trial motivated by walking difficulty and independence, but it is not itself a direct walking-performance test. The registry separately lists change in the Figure 8 Walk Test and change in the Modified Gait Efficacy Scale among secondary outcomes. Keeping the outcomes distinct helps readers avoid treating a change in perceived overall function as equivalent to a change in walking performance.

The registry names baseline and 12 weeks as the endpoint timeframe. Although it lists standard error as the dispersion measure for the primary outcome, the posted primary analysis contains no mean change, treatment contrast, standard error, or confidence interval. Those values are not reported in the registry record. Consequently, the posted p-value alone cannot show the size or direction of the estimated change.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary analysis is identified as a mixed models analysis. In general, mixed models can represent more than one source of variation, such as differences between groups of participants and repeated observations from the same participant. They can be useful when observations are correlated rather than independent. The registry record does not give the model formula, the variables included, the covariance assumptions, or the method used to estimate uncertainty, so those details cannot be assessed.

Why does cluster randomization matter?

In general, cluster randomization assigns groups, such as settings or facilities, rather than assigning each participant independently. People in the same cluster can share an environment, staff, or other influences, so their outcomes may be correlated. This correlation reduces the amount of independent information in the participant-level data compared with a situation in which all observations are independent. An analysis that ignores clustering can produce uncertainty estimates that are too small.

The record identifies this trial as cluster-randomized and states that a simple individual-level re-analysis would be misleading. It also says that only the sponsor’s own analysis is shown. The number of clusters included in each analysis, the cluster-level allocation details, and the approach used to account for clustering are not reported in the registry record. The description of 32 settings in the summary does not establish how many contributed data to each comparison or analysis.

What does a p-value convey?

In general, a p-value is calculated under a statistical model and a null hypothesis. It indicates how unusual data at least as incompatible with that null hypothesis would be if the model and null hypothesis were correct. It does not quantify the treatment effect, establish causation by itself, or tell readers whether a result is important to participants. Interpretation also depends on study design, data quality, model assumptions, and the broader analysis plan.

The posted primary result is p = 0.269. Because no effect estimate or confidence interval is reported, the direction and magnitude of the estimated difference cannot be read from the p-value. A confidence interval, in general, gives a range of values compatible with the data and specified statistical method at a stated confidence level. Its width conveys precision, subject to the assumptions of that method. No such interval is reported for the primary result.

Why report an effect estimate as well?

A treatment contrast or change estimate gives the scale and direction of the observed result. A confidence interval helps show the uncertainty around that estimate. Together, these are more informative about magnitude and precision than a p-value alone. For a continuous outcome such as the LLFDI score, the estimate could be expressed in units on the scale, but the registry does not report the estimate for the primary analysis. No value can be reconstructed from the p-value alone.

What does the record say about planning?

The registry includes a description of a sample-size planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It describes the effect to detect as a stated fraction of the observed effect. The record says that non-time-to-event planning values are participants per arm. However, no resulting planning values or observed-effect estimate are included in the registry record for this explanation. The illustration is not evidence of observed power, and it should not be mistaken for the trial’s original design justification. The registry record does not report the original sample-size justification.

How should multiple outcomes be considered?

The registry lists 16 outcome measures and 16 analyses. In general, when many statistical tests are conducted, the chance of at least one apparently unusual result can increase if each test is interpreted without regard to the others. A prespecified primary outcome can help focus interpretation, while multiplicity procedures can address particular families of tests. The registry record does not report whether a multiplicity adjustment was used or how the analysis family was defined.

What is missing for a full methods assessment?

The record does not report the analysis population, handling of missing outcome data, model diagnostics, or the detailed mixed-model specification. It does not report whether the analysis followed an intention-to-treat principle or how deviations from assigned programs were handled. Without these details, readers cannot determine the sensitivity of the primary result to those choices. These omissions are limits of what can be assessed from the registry record; they do not establish that a particular method was or was not used.

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("On the Move Exercise Group - Exercise Leader", "Standard Group Exercise Program - Exercise Leader", "On the Move Exercise Program - Staff Activity Pers", "Standard Exercise Program - Staff Activity Personn")
n   <- c(152, 146, 49, 77)
m   <- c(0.4, -0.6, -1.37, -0.32)
sp  <- c(5.7, 5.8, 4.68, 6.03)
sd  <- sp * sqrt(n)      # standard errors converted to SDs
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  On the Move Exercise Group - Exercise Leader  152  0.400  70.274  -10.862  11.662
CARM  Standard Group Exercise Program - Exercise Leader  146  -0.600  70.082  -12.063  10.863
CARM  On the Move Exercise Program - Staff Activity Pers  49  -1.370  32.760  -10.780  8.040
CARM  Standard Exercise Program - Staff Activity Personn  77  -0.320  52.913  -12.330  11.690

11. Analyses Reported by the Sponsor

The posted primary result is the sponsor’s mixed models analysis, reported as p = 0.269 for change in self-reported overall function from baseline to 12 weeks. No simple recalculation is presented. The registry identifies the study as cluster-randomized and specifically notes that an individual-level re-analysis would be misleading; appropriate inference needs to respect the clustered design.

The posted result does not include an effect estimate or confidence interval. It is therefore not possible to compare the sponsor’s estimate with a recalculated estimate of the size and precision of the contrast. The p-value is not enough to recover those quantities. The registry record does not report the model specification or the cluster-adjusted estimates needed for a fuller comparison.

The sponsor’s analysis is consequently the only primary inferential result available in the record. Its interpretation remains limited by the absence of the estimated contrast, interval, and detailed model information. No independent recalculation should be treated as a substitute for that analysis in this cluster-randomized trial.

12. Multiplicity, Missing Data and Analysis Populations

The registry lists 16 outcome measures and 16 analyses. The primary endpoint is change in LLFDI overall function from baseline to 12 weeks. The secondary outcomes include participant reports about benefit, challenge, individualized instruction, safety, satisfaction, and willingness to continue, as well as changes in the Figure 8 Walk Test and Modified Gait Efficacy Scale. The record does not report how these outcomes were organized into statistical families or whether the primary endpoint was designated before analysis.

In general, testing multiple outcomes can increase the chance of finding at least one result that appears statistically unusual by chance. Statistical plans may address this through a hierarchy of outcomes, adjusted significance thresholds, or other methods. The registry record does not report whether such procedures were used. The p-value for the primary outcome should therefore be read as the result for that reported analysis, not as a summary of all outcomes.

Information about missing data is also limited. The registry record does not report the amount or pattern of missing primary outcome measurements, the method used to handle them, or whether sensitivity analyses were conducted. It does not report the analysis population or whether participants were analyzed according to their assigned group. These details matter because the estimates and uncertainty can depend on who contributes data and on assumptions about missing observations.

The record does not describe interim analyses, stopping rules, or a full statistical analysis plan. Those matters are not reported in the registry record. Their absence from this account does not establish that they were not considered; it means that their role cannot be evaluated from the registry information available.

13. 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 serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: chest pain (1.3%).

The registry reports serious adverse events for the four intervention groups. The On the Move exercise leader group had 0 serious events among 152 at risk; the standard program exercise leader group had 0 among 146; the On the Move staff activity personnel group had 0 among 49; and the standard program staff activity personnel group had 1 among 77. These are the registry’s reported counts and group denominators.

The record lists chest pain at 1.3% among the top serious adverse event terms. It does not identify that term with a particular group in the information available for this explanation. The other adverse event counts are 4 in the On the Move exercise leader group, 0 in the standard program exercise leader group, 2 in the On the Move staff activity personnel group, and 0 in the standard program staff activity personnel group. These counts should not be conflated with the serious-event counts.

The registry record does not report deaths for these groups. It also does not provide enough detail to assess event timing, relatedness, severity definitions, or comparative statistical testing. Counts alone do not establish whether an intervention caused an event or whether groups differ in risk. They describe what the registry reports, without resolving those questions.

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

The primary result concerns change in self-reported overall function, measured with the LLFDI, from baseline to 12 weeks. The registry reports a mixed-model p-value of 0.269. It does not report the estimated group contrast, its direction, or a confidence interval. The posted result therefore does not show how large the estimated difference was or how precisely it was measured.

In general, statistical significance and practical importance are different questions. A p-value does not indicate whether a difference is meaningful to participants, and a non-small p-value does not establish that groups are equivalent. Demonstrating equivalence or non-inferiority requires a design and analysis that address those questions directly. The registry record does not report such a design or conclusion for the primary endpoint.

The trial’s intervention descriptions distinguish a walking-focused program from a standard seated program, and exercise-leader delivery from staff activity personnel delivery. The primary result reported in the registry does not provide separate estimates for each of those comparisons. It cannot, on its own, establish whether delivery arrangements differ or whether one program’s estimated change was larger than another’s.

The endpoint is self-reported overall function, not a direct measure of walking alone. The registry lists walking-related measures among the secondary outcomes, but their numerical results are not reported in the record information. The primary result should not be treated as a substitute for those outcomes.

Finally, the clustered design affects the interpretation of uncertainty. The sponsor’s mixed-model result is the reported analysis, while the registry states that a simple participant-level re-analysis would be misleading. Without the model details, effect estimate, and interval, readers can identify the analysis and its p-value but cannot fully judge the size, precision, or robustness of the estimated comparison.

15. Why This Trial Matters Statistically

This trial raises statistical issues that are common in studies of group programs. First, randomization by cluster changes how information is counted. Participants sharing a facility or setting may have correlated outcomes, so the analysis needs to account for the assignment structure rather than treating every participant as an independent randomized unit. The registry explicitly warns that a simple individual-level re-analysis would be misleading.

Second, the study combines two program types with two delivery arrangements. This creates several possible comparisons: the walking-focused program against the standard program, and exercise-leader delivery against staff delivery. Clear reporting of the intended contrasts and their estimates is important when a trial has multiple intervention dimensions. The primary result reported in the registry does not provide separate estimates for those comparisons.

Third, an endpoint’s meaning depends on what it measures. The LLFDI overall function score is self-reported and has a defined scale direction. It addresses perceived function, while the listed walking tests address different aspects of walking. These measures can complement one another, but they should not be treated as interchangeable.

Finally, transparent reporting requires more than a test result. The p-value is posted, but the primary effect estimate, confidence interval, analysis population, missing-data approach, and detailed model specification are not reported in the registry record. Those omissions limit assessment of magnitude and precision. They also show why a p-value should be read alongside estimates, uncertainty, design details, and the analysis plan.

16. 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 reported without an effect estimate or confidence interval. The p-value alone cannot establish the direction, magnitude, or precision of the estimated change in overall function. The registry record also does not provide the detailed mixed-model specification, including how clustering and repeated measurements were represented. This makes it difficult to assess the analysis assumptions independently.

The cluster-randomized design is a further interpretive constraint. The record states that a simple individual-level re-analysis would be misleading, and only the sponsor’s own analysis is shown. The number of clusters contributing to each analysis and the cluster-level allocation details are not reported in the registry record. The summary’s reference to 32 settings does not supply those analysis details.

The registry lists 16 outcome measures and 16 analyses but does not report the multiplicity strategy, analysis population, or whether the reported analyses followed a prespecified plan. It also does not report missing-data amounts, handling methods, or sensitivity analyses. These gaps prevent a complete assessment of selection and robustness.

The record describes enrollment as 424, while the brief summary describes a plan involving 400 older adults; it does not explain the difference. The registry also does not report the original sample-size justification. The sample-size planning description is an illustration based on an observed effect, not evidence of observed power, and no planning outputs are reported.

For safety, the record gives event counts but does not provide deaths, event timing, relatedness, or detailed comparative analyses. The primary endpoint is self-reported overall function, and numerical results for the listed secondary outcomes are not included in the information. These limitations bound what can be concluded from the registry record.

17. Related Tutorials

18. Related Statistical Calculators

19. Sources

• ClinicalTrials.gov: On the Move: Optimizing Participation in Group Exercise — NCT01986647.
• Registry record last updated 2019-03-22; status last verified 2018-12.
• Results first posted 2019-03-22.
• 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.

20. Record Summary

NCT01986647 is a completed, randomized, single-masked, parallel, cluster-randomized trial of group exercise in community-dwelling older adults described as being at risk of walking difficulty. Enrollment is listed as 424. The four intervention descriptions combine On the Move or standard seated exercise with delivery by an exercise leader or staff activity personnel.

The primary endpoint was change in LLFDI overall function from baseline to 12 weeks. The registry reports a mixed-model p-value of 0.269, but no primary effect estimate or confidence interval. The record lists 16 outcome measures and 16 analyses. It also reports serious adverse event counts across the four groups. Important analysis details, including the model specification, analysis population, missing-data handling, and multiplicity approach, are not reported in the registry record.