This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Exercise for Brain Health in the Fight Against Alzheimer's Disease (NCT03727360), a randomized na study. The primary outcome is Rey Auditory Verbal Learning Test Sum of Trials 1-5.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03727360 |
| Phase | NA |
| Condition | Healthy Cognition |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 124 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Maryland, College Park |
| Results posted | Yes |
2. Clinical Question
The study asks whether a six-month exercise program is associated with changes in episodic memory and brain-related measures in cognitively healthy, physically inactive older adults. Participants were assigned to moderate-intensity exercise training or a low-intensity flexibility exercise control. The stated primary aims include comparing pre-intervention and post-intervention changes in episodic memory performance and MRI biomarkers. The registered primary outcome is the Rey Auditory Verbal Learning Test sum of Trials 1-5.
Population
Cognitively healthy and physically inactive older adults ages 60-80. The study description includes both APOE-ε4 allele carriers and non-carriers. The primary outcome population is described as participants who completed their intervention arm and both baseline and 6-month testing.
Intervention
Supervised moderate-intensity aerobic exercise training for six months. The exercise description includes group exercise delivered synchronously on Zoom, with dynamic cardiovascular exercise at 60-70% of maximal heart rate.
Comparator
A supervised low-intensity flexibility exercise control condition for six months. Its description includes group exercise delivered synchronously on Zoom and seated or floor exercise at 30-40% of maximal heart rate.
Primary question
How does the mean Rey Auditory Verbal Learning Test sum of Trials 1-5 change from baseline to 6 months in the two intervention groups? The registry record does not report a single result comparing those changes.
3. Trial Design
The study is registered as a randomized, single-masked, parallel-group trial. The registry lists an enrollment of 124 and a completed status. It gives a start date of 2018-10-08 and a primary completion date of 2024-04-30. The phase is listed as NA. The sponsor is the University of Maryland, College Park.
The intervention period is six months. The exercise training arm is described as moderate-intensity aerobic exercise, while the control arm uses low-intensity flexibility exercise. Both descriptions include group exercise delivered synchronously on Zoom. The exercise training description includes dynamic cardiovascular activity at 60-70% of maximal heart rate; the flexibility control description specifies seated or floor exercise at 30-40% of maximal heart rate. The registry summary also describes group-based exercise at local retirement communities near College Park, Maryland, or on the University of Maryland College Park campus. The record does not explain how these settings relate to the Zoom delivery description.
Random assignment supports a planned comparison between the intervention groups, but does not by itself establish how allocation was generated or concealed. Those details are not reported in the registry record. Masking is identified as single, but the record does not state who was masked. It also does not describe adherence, intervention fidelity, or whether the planned exercise sessions were completed as intended.
The primary outcome is assessed at baseline and 6 months. The registry defines its analysis population as people who completed the intervention arms and both testing occasions. That definition is narrower than a description of everyone assigned at random, and the record does not report how many participants met it. It also does not report the allocation counts, withdrawals, or reasons for non-completion.
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.
Before assignment: After informed consent, all physician consent and MRI screening forms were completed (approximately 2-6 weeks) before baseline testing was scheduled. Participants were then assigned to a treatment arm and completed the baseline testing. A total of 124 participants completed baseline, and 5 withdrew before starting the intervention. 119 started one of the two arms, and 106 of the 124 consented individuals completed the entire 6-month exercise intervention with baseline and follow-up testing.
Overall Study
| Stage | Exercise Training | Flexibility Control |
|---|---|---|
| STARTED | 64 | 55 |
| COMPLETED | 55 | 51 |
| NOT COMPLETED | 9 | 4 |
Analysis population for the primary outcome, as defined in the registry: These are the number of participants who completed the intervention arms and completed both the baseline and 6-month testing.
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: These are the number of participants who completed the intervention arms and completed both the baseline and 6-month testing.
| Characteristic | Unit | Exercise Training | Flexibility Control | Total |
|---|---|---|---|---|
| Participants analysed | 55 | 51 | 106 | |
| Age, Continuous | Years | 68.4 (SD 6.2) | 67.8 (SD 5.6) | 68.1 (SD 5.9) |
| Sex: Female, Male: Female | Participants | 45 | 39 | 84 |
| Sex: Female, Male: Male | Participants | 10 | 12 | 22 |
| Race/Ethnicity, Customized: Self-Reported Race – Prefer not to say | Participants | 2 | 1 | 3 |
| Race/Ethnicity, Customized: Self-Reported Race – White | Participants | 43 | 37 | 80 |
| Race/Ethnicity, Customized: Self-Reported Race – Black | Participants | 7 | 11 | 18 |
| Race/Ethnicity, Customized: Self-Reported Race – Asian | Participants | 3 | 2 | 5 |
| Education: High School | Participants | 4 | 0 | 4 |
| Education: Some College | Participants | 2 | 0 | 2 |
| Education: Bachelors Degree | Participants | 12 | 21 | 33 |
| Education: Graduate Degree | Participants | 27 | 22 | 49 |
| Education: Doctoral Degree | Participants | 10 | 8 | 18 |
6. Primary Endpoint
The registry lists the primary outcome as Rey Auditory Verbal Learning Test Sum of Trials 1-5, measured over Baseline and 6 months.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | Sum of words recalled Trials 1 to 5 |
| Endpoint classification | Continuous Endpoint |
The registered primary endpoint is the Rey Auditory Verbal Learning Test sum of Trials 1-5, measured as the sum of words recalled across those trials. In the test description, fifteen words are presented verbally, and the participant is asked to recall as many as possible after each trial. The recorded score is the total number of correctly recalled words across Trials 1-5.
This continuous measure is used to assess episodic memory performance: it records how much verbal information a participant recalls across repeated learning trials. Because the study describes testing at baseline and 6 months, the question concerns change in the score over the intervention period and how that change compares between the exercise training and flexibility control groups.
The endpoint is recorded as a mean with standard deviation, but the registry record does not report the group means, standard deviations, changes, or a between-group estimate. It also does not report a threshold for a meaningful change in this score. Therefore, the endpoint definition clarifies what was measured, but does not establish the direction or size of any observed difference. The study summary also names MRI biomarkers among its primary aims, but the specific MRI measures and their results are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies the question and the outcome, but does not provide a single primary-outcome comparison that can be interpreted as an estimated treatment effect. It gives no group-level Rey Auditory Verbal Learning Test means, standard deviations, changes from baseline, between-group estimate, confidence interval, or p-value. The record indicates that the primary outcome has several categories or time points and was not reduced to one comparison. It lists zero analyses. Consequently, the posted record does not establish whether the groups differed in memory-score change, the direction of any difference, or how precisely such a difference was estimated.
That absence is not evidence that the groups had identical outcomes. It means the registry record does not present the result in a form that permits a quantified comparison. A difference estimate would describe the contrast between groups; a confidence interval would indicate the precision and range of estimates compatible with the data under the analysis assumptions. Neither is available for the primary outcome in this record. The direction and statistical compatibility of the result therefore cannot be judged from the registry information.
The trial's randomized parallel design makes a between-group comparison relevant, but interpretation still depends on the actual analysis, the population included, and how missing follow-up measurements were handled. The record defines the primary outcome population as participants who completed their intervention arms and both baseline and 6-month testing. It does not report the number meeting that definition or explain how their outcomes were analyzed. Without those details, it is not possible to assess how closely the posted analysis represents all participants assigned to the arms.
The record describes additional aims involving MRI biomarkers and lists Peak Rate of Oxygen Consumption (VO2peak) and the 6 Minute Walk Test as secondary outcomes. It does not provide their results or methods of analysis. Their presence indicates that the study considered outcomes beyond verbal memory, but does not support conclusions about those measures.
The adverse-event information is descriptive and should be read separately from efficacy. It lists serious and other affected-event counts by arm, but does not provide a comparative safety analysis or enough context to infer causal attribution. The registry's completed status describes the trial record; it does not supply the missing outcome estimates. Overall, the posted record describes a trial question and design, while leaving the primary effect estimate and its uncertainty not reported in the registry record.
9. Statistical Methods Explained
The registry describes the primary outcome as a continuous measure summarized by a mean and standard deviation. That format is appropriate for explaining the average score in a group and the spread of scores around that average. However, those summaries alone would not answer the randomized comparison: the central question is how the change in the exercise training group compares with the change in the flexibility control group. The relevant estimate and its uncertainty are not reported in the registry record.
What does a between-group estimate represent?
In a randomized parallel-group study, a between-group estimate contrasts outcomes in the assigned intervention groups. For a baseline-to-follow-up endpoint, an analysis might compare follow-up scores while accounting for baseline values, or compare changes from baseline. These approaches can yield different estimates and rely on different model specifications. This is general statistical context, not a description of the analysis used in this trial. The registry record does not report the model, covariates, or exact contrast used for the primary outcome.
A confidence interval expresses uncertainty around an estimated effect. A narrower interval generally indicates greater precision, while a wider interval indicates less precision. Statistical significance and clinical importance are separate considerations: an interval or p-value does not alone determine whether a difference matters to participants. In this record, no primary estimate, interval, or p-value is available, and no threshold for a meaningful score change is reported. The magnitude, precision, and practical importance of any primary-outcome difference therefore cannot be evaluated.
What does randomization contribute?
Random assignment is intended to make the groups comparable, on average, with respect to factors that could affect outcomes. This supports causal interpretation when the analysis and follow-up preserve the randomized comparison. Randomization does not ensure that every factor is balanced in a particular trial, does not prevent missing outcome data, and does not substitute for transparent reporting of the analysis. The record identifies randomization but does not report the sequence-generation method, allocation concealment, or group allocation counts.
The registry identifies masking as single but does not specify which people were masked. Masking can reduce the influence of expectations on outcome assessment or other study processes, depending on who is masked and what procedures are used. Without that information, the likely role of masking in this trial cannot be assessed.
How should the planning assumptions be read?
The record describes sample-size planning illustrations based on the observed effect, using a two-sided significance level of 0.05, equal allocation between the groups, and a normal approximation. It states that the target effect is expressed as a fraction of the observed effect. These are planning assumptions, not results of a trial-designed sample-size justification. The record does not report the original sample-size justification or an actual planning target. Any sample-size illustration based on an observed effect is a hypothetical planning exercise; it is not observed power and does not measure the probability that the completed trial detected an effect.
A planning calculation can help show how the assumed effect size and statistical design relate to a future study's required size. Such a calculation does not repair an unreported outcome estimate, and it should not be treated as independent confirmation of an intervention effect. The registry record does not report the numeric planning outputs or the effect estimate on which they depend. No additional sample-size value can therefore be interpreted from the record alone.
Why might variability matter?
For a continuous score, standard deviation describes variation among participant scores. Greater variability can make a group contrast less precise when other design features are held constant. If outcomes are more variable than an analysis assumes, standard errors and confidence intervals may not reflect uncertainty well. This is general statistical context. The primary score is described using a mean and standard deviation, but the registry does not report the observed standard deviations or diagnostics about the outcome distribution.
Repeated measurements may also be correlated: a participant's baseline score can be related to that participant's follow-up score. General methods for repeated measures can account for this dependence, but the registry does not identify the approach used. The record gives the assessment occasions as baseline and 6 months without describing whether all measurements were available or how incomplete pairs were handled.
The registry therefore supports a clear description of the design and measurement, but not a reconstruction of the primary statistical analysis. The model, analysis population beyond the stated completer definition, handling of missing data, covariate adjustment, multiplicity approach, and primary effect estimate are not reported in the registry record. These omissions limit reproducibility and prevent a full assessment of statistical precision.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists several aims and outcomes, including episodic memory, MRI biomarkers, Peak Rate of Oxygen Consumption (VO2peak), and the 6 Minute Walk Test. When a study examines several outcomes, time points, or comparisons, the chance of a false-positive finding across the full set of tests can increase. General approaches include identifying a primary comparison in advance, adjusting inference for multiple testing, or describing secondary analyses as exploratory. The registry record does not report a multiplicity strategy. It also does not provide enough outcome results to determine which comparisons were analyzed or how they were interpreted.
The primary outcome is described at baseline and 6 months, while the record notes that it has several categories or time points and was not reduced to one comparison. It does not state which contrast was intended to be primary, how any repeated measurements were modeled, or whether subgroups such as APOE-ε4 carriers and non-carriers were analyzed. A subgroup description in the study summary does not establish that subgroup analyses were performed.
Missing-data methods are not reported in the registry record. The stated primary-outcome population consists of participants who completed their intervention arms and both baseline and 6-month testing. This makes completion part of the recorded population definition, but does not explain what happened to assigned participants without complete testing. The record does not give missingness counts, reasons, imputation methods, or sensitivity analyses. It also does not report an intention-to-treat analysis or another analysis population beyond the stated completer description.
These details matter because missing outcomes and selective emphasis among multiple analyses can affect how an estimate should be interpreted. The registry record does not provide enough information to determine whether either issue altered the reported findings.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Exercise Training | 3 | 64 | 4.7% |
| Flexibility Control | 1 | 55 | 1.8% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Exercise Training | 0 of 64 |
| Flexibility Control | 0 of 55 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Exercise Training | 10 of 64 |
| Flexibility Control | 8 of 55 |
Most frequent serious adverse event terms
| Event term | Organ system | Exercise Training | Flexibility Control |
|---|---|---|---|
| Surgical Procedure | General disorders | 1 of 64 | 1 of 55 |
| fainted | General disorders | 1 of 64 | 0 of 55 |
| Fall | General disorders | 1 of 64 | 0 of 55 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Exercise Training | Flexibility Control |
|---|---|---|---|
| Unrelated joint/muscle injury/pain | Musculoskeletal and connective tissue disorders | 5 of 64 | 4 of 55 |
| Mild joint/muscle pain during exercise | Musculoskeletal and connective tissue disorders | 2 of 64 | 1 of 55 |
| Minor medical procedure that led to short-term disruption of participation | General disorders | 0 of 64 | 2 of 55 |
| Fall off of yoga ball | General disorders | 1 of 64 | 0 of 55 |
| Discomfort after MRI scan | General disorders | 0 of 64 | 1 of 55 |
| Fall at home, no injury | General disorders | 1 of 64 | 0 of 55 |
| Mild dizziness after fasting blood draw | General disorders | 1 of 64 | 0 of 55 |
Serious events with the highest arm-level rate: surgical procedure (1.8%), fainted (1.6%), fall (1.6%).
The registry lists serious adverse events and other adverse events separately for the two arms. For Exercise Training, the serious-event figures are 3 affected among 64 at risk, and the other-event figures are 10 affected among 64 at risk. For Flexibility Control, the serious-event figures are 1 affected among 55 at risk, and the other-event figures are 8 affected among 55 at risk. Deaths are recorded as 0 in each arm.
These are descriptive registry counts. They should not be treated as a causal comparison: the record does not give a safety analysis, event timing, participant-level detail, or information about whether events were judged related to the intervention. The listed at-risk counts should be read as the denominators associated with the registry entries, not as proof that every assigned participant contributed equally to follow-up.
The top serious-event terms are listed as Surgical Procedure, 1.8%; fainted, 1.6%; and Fall, 1.6%. The record does not explain the denominator or attribution for these term percentages, nor does it assign the terms to a particular arm. The terms should not be added to the arm-level counts or interpreted as an intervention effect. The registry record does not report further detail needed to assess severity, timing, or relatedness.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, parallel-group trial compared a six-month moderate-intensity exercise training program with a low-intensity flexibility control in cognitively healthy, physically inactive older adults ages 60-80. It identifies the Rey Auditory Verbal Learning Test sum of Trials 1-5 as the primary outcome and specifies baseline and 6-month assessment. This information clarifies the intended population, contrast, and memory measure.
The record does not establish the size or direction of a difference in memory change between groups. It reports no primary-outcome means, change estimates, confidence interval, or p-value, and it does not provide a single comparison for the primary outcome. It therefore cannot support a conclusion that the exercise training group had better, worse, or similar memory outcomes than the flexibility control group. Lack of a reported comparison should not be read as evidence of no effect.
The study summary identifies MRI biomarkers as part of the primary aims, and the record lists fitness and walking outcomes as secondary measures. Their results are not reported in the registry record. No conclusion about those outcomes can be drawn from the intervention descriptions or the adverse-event counts.
The safety entries describe affected-event counts and deaths by group, with additional serious-event terms. They do not establish that the intervention caused or prevented any event. The record does not provide a comparative safety analysis or the attribution and timing information needed for that interpretation.
Thus, the registry record is informative about the trial's design and intended questions but incomplete for evaluating outcome effects. Assessing the intervention contrast would require reported outcome estimates, their uncertainty, and the analysis details, including how incomplete follow-up and multiple outcomes were handled. Those elements are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial is statistically interesting because it compares an aerobic exercise program with an active flexibility control rather than relying on a no-intervention comparison. Such a design asks whether outcomes differ between two organized exercise conditions, not simply whether participants receiving group activity differ from people receiving no structured activity. The control condition is therefore central to interpreting what the randomized contrast would represent.
The study also focuses on cognitively healthy, physically inactive older adults and describes inclusion of APOE-ε4 carriers and non-carriers. This makes clarity about the population and any subgroup analyses important. The registry describes those participant characteristics, but does not report a subgroup analysis or show whether effects varied between carrier groups. Without results, the biological motivation cannot be treated as evidence of differential benefit or harm.
The primary endpoint turns a memory task into a continuous score based on correctly recalled words across Trials 1-5. A repeated assessment at baseline and 6 months allows the study to frame a change question. Statistical interpretation depends not only on the score itself but also on the contrast, follow-up completeness, and precision of the estimate. The record does not report those outcome results or analysis choices.
For biostatisticians and clinical researchers, the record illustrates why registration details and posted results serve different purposes. Design information can establish what investigators intended to compare, while analysis reporting is needed to evaluate what the data show. Here, the randomized design and endpoint are described, but the primary effect estimate and key analysis details are not reported in the registry record. The statistical significance of the study cannot be inferred from its completed status, enrollment entry, or planning assumptions.
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 record is that the primary outcome is not presented as a single between-group comparison. No group means, standard deviations, change estimates, confidence interval, or p-value are reported for the Rey Auditory Verbal Learning Test sum of Trials 1-5. The record lists zero analyses and explicitly indicates that the primary outcome has several categories or time points and was not reduced to one comparison. This prevents assessment of effect direction, magnitude, and precision.
The record defines the primary outcome population by intervention completion and completion of baseline and 6-month testing, but does not report the number included or the number excluded from that population. It does not describe missing-data handling, withdrawals, adherence, or the analysis model. The sequence-generation and allocation-concealment methods are not reported, and the identity of the masked party is unspecified.
The registry describes MRI biomarkers as part of the primary aims, but does not specify the measures or report their results. It lists secondary fitness and walking outcomes without outcome estimates. The record does not explain the relationship between the stated local or campus exercise settings and the Zoom delivery descriptions. It also does not report a multiplicity strategy, subgroup analysis, or a threshold for meaningful change in the memory score.
Finally, the adverse-event entries are limited to arm-level counts and listed serious-event terms. Timing, attribution, and comparative safety methods are not reported in the registry record. These limitations concern what can be learned from the posted record and do not establish that the trial itself lacked such procedures or analyses.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Exercise for Brain Health in the Fight Against Alzheimer's Disease — NCT03727360.
- Registry record last updated 2026-05-01; status last verified 2026-04.
- Results first posted 2026-05-01.
- 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.
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18. Record Summary
NCT03727360 is a completed, randomized, single-masked, parallel-group trial sponsored by the University of Maryland, College Park. The registry lists enrollment of 124, a start date of 2018-10-08, and a primary completion date of 2024-04-30. The study compares six-month moderate-intensity exercise training with a low-intensity flexibility exercise control in cognitively healthy, physically inactive older adults ages 60-80.
The primary registered measure is the Rey Auditory Verbal Learning Test sum of Trials 1-5, assessed at baseline and 6 months. The registry describes MRI biomarkers as part of the study's primary aims and lists Peak Rate of Oxygen Consumption (VO2peak) and the 6 Minute Walk Test as secondary outcomes. It reports adverse-event counts by arm and deaths recorded as 0 in each arm.
The registry record does not report a single primary-outcome comparison, an effect estimate, or its uncertainty. Analysis methods, missing-data procedures, and a multiplicity strategy are also not reported in the registry record.