Time Restricted Eating Outcomes in Multiple Sclerosis: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Time Restricted Eating Outcomes in Multiple Sclerosis (NCT04389970), a na na study. The primary outcome is Timed 25-foot Walk Speed.

2. Clinical Question

3. Trial Design

This completed pilot study, NCT04389970, is titled “Time Restricted Eating Outcomes in Multiple Sclerosis.” The sponsor is the University of Alabama at Birmingham. The record lists the study start as 2020-10-01 and primary completion as 2021-07-30. Its phase and allocation are recorded as NA, and its model is single-group. Masking is listed as none.

The intervention is behavioral: participants were asked to follow a time-restricted meal pattern described as an 8:16 protocol. The study summary specifies eating within an 8-hour daily window and not eating during the remaining 16 hours, for 8 weeks. As a single-group study, it does not provide a concurrent control group for estimating what would have happened over the same period without the intervention. The baseline-to-follow-up contrast can describe change over time in the study group, but by itself cannot separate intervention effects from other influences on change.

The registry lists enrollment as 12. That is the recorded enrollment, not a reported count of people who completed the intervention or contributed data to every analysis. For the primary outcome, the stated analysis population consists only of study completers. How many participants completed the study, and how missing observations were handled, are not reported in the registry record.

The registry identifies the study as a pilot intended to examine preliminary efficacy, safety, and acceptability. It lists a primary walking-speed endpoint and additional outcomes addressing pain, fatigue, sleep, body composition, and performance measures. The number of outcome measures and analyses recorded is 9 for each. The trial’s own sample-size justification, any planned interim analyses, and a detailed statistical analysis plan 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:

Analysis population for the primary outcome, as defined in the registry: Only study completers were included in the analysis.

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 Timed 25-foot Walk Speed, measured over Change from baseline to 8 weeks.

The primary endpoint is change in timed 25-foot walk speed from baseline to 8 weeks, expressed in feet per second. The timed walk assesses how quickly a participant walks a fixed distance; expressing the result as speed makes higher speed a better score, according to the registry description. Walking performance is relevant to assessing mobility in a study involving multiple sclerosis.

The registry defines the change as speed at baseline minus speed at 8 weeks. That sign convention deserves attention: a positive value under this formula means baseline speed was higher than the 8-week speed, while a negative value means 8-week speed was higher than baseline speed. This is the reverse of a follow-up-minus-baseline convention sometimes used for change scores. The record also states that higher scores indicate a better outcome, referring to the speed measure. Readers should therefore distinguish the direction of the speed scale from the direction of the calculated change.

The registry says there are no minimum or maximum values for this measure. It specifies that only study completers were included in the primary-outcome analysis. No numerical baseline or follow-up speeds, change estimate, measure of variability, confidence interval, or test result for this endpoint is reported in the registry record. The endpoint definition explains what was intended to be measured, but does not establish the size or precision of any observed change.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation starts with the design. This is a single-group study, not a randomized comparison. The primary contrast is within the same study group over time: baseline versus 8 weeks. In general, a within-group change can describe how a measured outcome differs between two occasions. It does not by itself identify why the outcome changed. Without a concurrent comparator, effects of the intervention cannot be separated from other time-related changes, measurement variation, or influences that occur alongside the intervention.

What does the change score represent?

A change score is calculated by subtracting one measurement occasion from another. The order of subtraction determines its sign. In this study, the registry defines change as baseline speed minus speed at 8 weeks. Therefore, a positive change corresponds to a lower follow-up speed, and a negative change corresponds to a higher follow-up speed. The underlying speed scale is interpreted differently: higher speed is described as better. Keeping the scale direction separate from the change-score direction prevents a sign from being read as though it were automatically favorable or unfavorable.

The endpoint uses feet per second and is based on a timed 25-foot walk. A mean change, if reported, would describe the average signed difference under the registry’s definition. It would not show whether every participant changed in the same direction. Individual results can vary around a group mean, and a mean alone does not describe the full spread of outcomes. The registry identifies standard deviation as the dispersion measure for the primary continuous outcome, but numerical outcome summaries are not reported in the registry record.

How should uncertainty be understood?

For a continuous outcome, an estimate is more informative when accompanied by a measure of uncertainty. A confidence interval is a statistical range calculated from data using a specified method. In general, it conveys the values compatible with the observed estimate and the assumptions of that method. Its width helps communicate precision: wider intervals reflect less precision than narrower intervals. A confidence interval is not a guarantee that the true effect lies within its endpoints, and it does not address biases caused by study design or missing data.

A p-value, when used, assesses how compatible the observed data are with a specified null model, conditional on the analysis assumptions. It does not measure the probability that the null hypothesis is true, and it does not measure the size or clinical importance of a change. The registry record does not report a primary-outcome estimate, confidence interval, or p-value, so none can be interpreted for this endpoint.

What does a single-group comparison leave unresolved?

A baseline-to-follow-up analysis can be useful for describing change in a pilot study, especially when the goal is to assess feasibility and gather preliminary outcome information. However, it lacks the protection against time-related alternative explanations that a suitable concurrent comparison can provide. Participants may change for reasons unrelated to the assigned eating pattern; in a single-group design, those possibilities cannot be separated through a between-group contrast. A statistical test of within-group change would not remove this design limitation.

Another consideration is the analysis population. The primary outcome description says only study completers were included. In general, a completer analysis uses observations from participants who finish the study, but may not represent everyone enrolled if completion is related to outcome or experience. Assessing that possibility requires information about completion, missing observations, and the analysis rules. Those details are not reported in the registry record. The recorded enrollment of 12 should therefore not be treated as the primary endpoint analysis count.

Why do dispersion and distribution matter?

Standard deviation describes the spread of individual measurements around their mean. It is not the uncertainty of the mean itself, and it should not be read as though it were a confidence interval. For small samples, estimates of both the mean and variability can be sensitive to individual observations. A summary of the mean and standard deviation can therefore be supplemented by individual-level displays or robust methods when appropriate, but the available registry information does not state which additional methods were used.

Over-dispersion is a general concern when data vary more than a statistical model assumes. In such cases, standard errors may be too small if the model does not account for the extra variability, producing uncertainty estimates that are too optimistic. This concept is most directly relevant to models for counts or other outcomes with variance assumptions; the primary endpoint is continuous. No model specification, distributional assessment, or adjustment procedure is reported for the primary analysis, so it would be inappropriate to claim that over-dispersion was tested or present.

What do the planning assumptions mean?

The registry includes assumptions for a planning illustration based on an observed effect: two-sided significance level 0.05, equal allocation between two arms, and a normal approximation, with the detectable effect expressed as a stated fraction of the observed effect. These are planning assumptions, not a description of this trial’s single-group design. The illustration’s two-arm allocation does not mean the study actually had two arms. It should not be confused with an observed comparison or a trial-specific design justification.

Sample-size illustrations describe how many participants per arm a hypothetical future comparison might require under its assumptions. They do not show that a study had adequate power after it was conducted, and they are not observed power. The registry does not report the trial’s own sample-size justification. Without numerical illustration outputs in the registry information, no planning count can be interpreted. In general, planning estimates depend on the assumed effect, variability, significance level, allocation, and analysis method; changing those assumptions changes the resulting requirement.

The registry records 9 outcome measures and 9 analyses. Multiple outcomes can raise multiplicity concerns because repeated testing creates more opportunities for findings that appear statistically notable by chance. Whether an adjustment is appropriate depends on the aims, outcome hierarchy, and analysis plan. Those details, including any multiplicity adjustment, are not reported in the registry record. The outcome list alone does not establish that a particular correction was 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("Time Restricted Feeding")
n   <- c(11)
m   <- c(-0.3)
sp  <- c(1.2)
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  Time Restricted Feeding  11  -0.300  1.200  -1.106  0.506

11. Multiplicity, Missing Data and Analysis Populations

The registry identifies one primary endpoint, timed 25-foot walk speed, and lists additional outcomes covering pain, fatigue, sleep, body composition, and performance. It records 9 outcome measures and 9 analyses. When several outcomes are examined, multiplicity can matter: testing many hypotheses can increase the chance of at least one apparently notable result even when no underlying effect exists. General approaches include defining a primary outcome in advance, adjusting for multiple tests, or treating secondary analyses as exploratory. The registry record does not report whether multiplicity was addressed, how the outcomes were prioritized in analysis, or whether the analysis plan specified any correction.

The primary outcome’s stated analysis population is study completers. Enrollment is recorded as 12, but the number of completers and the number with usable primary endpoint data are not reported in the registry record. The record does not explain whether participants with incomplete measurements were excluded, whether any values were imputed, or whether sensitivity analyses examined alternative missing-data assumptions. It also does not report reasons for missingness or study discontinuation.

These omissions affect interpretation because missing observations can reduce precision and may introduce bias if the chance of having an observed outcome is related to the outcome itself or to participant experience. A completer-only estimate describes the participants contributing under that rule; without further information, it cannot be assumed to represent everyone enrolled. No numerical primary-outcome results or uncertainty estimates are reported, so the impact of missingness on the estimate cannot be assessed.

The registry does not report whether an intention-to-treat analysis or another analysis population was used beyond the stated completer population for the primary outcome. Interim analyses and detailed statistical analysis procedures are also not reported in the registry record. These are unknowns, not evidence that a particular procedure was or was not performed.

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.

The adverse-event record lists the time-restricted-feeding group with 12 participants at risk for serious adverse events and zero affected. It also lists 12 at risk for other adverse events and zero affected, with zero deaths. No serious adverse-event terms are listed. These figures describe what the registry records for the study; they should not be interpreted as proof that no event could occur or that the intervention is safe for every person or setting.

A zero count is most useful when considered alongside the number observed, the duration of observation, and how events were collected and classified. The at-risk counts are recorded as 12 for each category, but the registry does not report the event-surveillance period, completeness of reporting, or detailed definitions and procedures for identifying events. It also does not provide information about exposure or follow-up for participants who may not have completed the study.

The record’s zero-event figures are descriptive and do not estimate a comparative safety difference, because there is no separate control group. They also do not establish that rare events are absent. The registry identifies safety as an aim, but the available adverse-event counts alone cannot characterize all aspects of tolerability or participant acceptability.

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

This study addresses a practical research question: whether a time-restricted eating pattern can be examined in a pilot study of adults with relapsing-remitting multiple sclerosis, with walking speed and other health measures among the outcomes of interest. The registry describes an 8:16 daily eating pattern planned for 8 weeks and identifies timed 25-foot walk speed as the primary endpoint. It also records safety and acceptability as aims.

The registry information does not include the numerical primary endpoint result. It therefore does not show the size, direction, or precision of change in walking speed. The endpoint definition alone cannot establish whether participants’ speed improved, worsened, or remained similar. Results for the other listed measures are also not reported in the registry record. The recorded adverse-event counts are zero in the categories listed, but those descriptive counts do not prove the absence of risk.

Even if a within-group change estimate were available, this design would describe change over time rather than isolate a causal effect. A single-group study has no concurrent control group to distinguish intervention-related change from other explanations. The study’s pilot purpose is consistent with preliminary investigation, but no trial-specific sample-size justification is reported. The enrollment count should not be interpreted as the number analyzed for the primary endpoint, because the registry states that only completers were included and does not report their number.

Accordingly, the record is useful for understanding the intervention format, the planned duration, the principal measure, and the analysis-population description. It does not support a quantitative claim about efficacy, a causal claim about the eating pattern, or a broad conclusion about safety. Those conclusions would require outcome estimates, uncertainty measures, fuller information on participants and missing data, and a design that can address alternative explanations for change.

14. Why This Trial Matters Statistically

This trial matters statistically because it illustrates the distinction between a measured change and an intervention effect. The primary endpoint compares walking speed at baseline and 8 weeks within a single group. Such a comparison can describe what happened over time in the analyzed participants, but without a concurrent comparator it cannot show how much of that change was caused by the intervention rather than by other influences.

It also highlights how a change-score definition can affect interpretation. The registry subtracts 8-week speed from baseline speed, while describing higher speed itself as better. Readers must track the subtraction order rather than infer the meaning of a positive change from the underlying scale. This is a general lesson for clinical outcome reporting: state both the measurement direction and the change-score convention clearly.

The pilot context also makes precision and feasibility important. A small study can generate preliminary information, but estimates may be imprecise and sensitive to individual observations. The numerical estimate and uncertainty for the primary endpoint are not reported in the registry record, so the precision of any observed change cannot be evaluated. Nor does the record identify the number of completers, despite specifying a completer-only primary analysis.

Finally, the trial illustrates why planned comparisons and actual design should not be conflated. The registry lists assumptions for a hypothetical two-arm sample-size planning illustration, while the study itself is single-group. Planning calculations are conditional on assumptions and are not observed power. Distinguishing those concepts helps readers avoid treating a planning exercise as evidence about the results or adequacy of the completed study.

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.

Several limitations are specific to the information recorded for this study. First, the design is single-group, with allocation listed as NA and no separate comparator. A before-and-after contrast cannot rule out changes over time that are unrelated to the eating pattern. This limits causal interpretation even if numerical outcome results are available elsewhere.

Second, the primary outcome is analyzed among study completers, but the registry does not report the number who completed the study or the number contributing endpoint data. It also does not describe missing-data handling, reasons for missingness, or sensitivity analyses. This makes it difficult to assess how representative the analyzed group may be of those enrolled.

Third, numerical primary and secondary outcome results are not reported in the registry record. Without estimates and uncertainty measures, the magnitude, direction, and precision of change cannot be assessed. The record also does not report a detailed statistical analysis plan, trial-specific sample-size justification, interim analyses, or any approach to multiplicity across outcomes.

Fourth, the registry’s change-score definition requires careful interpretation: baseline speed minus 8-week speed. This should not be confused with the direction of the speed scale, where higher speed is described as better. Finally, safety reporting is limited to recorded event counts. Surveillance duration and detailed collection procedures are not reported, so zero recorded events should be read descriptively rather than as comprehensive evidence about risk or acceptability.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Time Restricted Eating Outcomes in Multiple Sclerosis — NCT04389970.
• Registry record last updated 2024-03-27; status last verified 2024-03.
• Results first posted 2024-03-27.
• 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

NCT04389970 is a completed, single-group pilot study sponsored by the University of Alabama at Birmingham. It enrolled 12 participants and examined a behavioral time-restricted-feeding pattern described as eating within an 8-hour daily window and not eating for the remaining 16 hours, for 8 weeks. The primary endpoint was change in timed 25-foot walk speed from baseline to 8 weeks, with the primary analysis restricted to study completers.

The registry lists additional outcomes concerning pain, fatigue, sleep, body composition, and performance, and identifies preliminary efficacy, safety, and acceptability as aims. It records zero serious adverse events, zero other adverse events, and zero deaths in the intervention group. Numerical results for the primary and other outcomes, the number of completers, and detailed analysis procedures are not reported in the registry record.