Evaluation of a Daily Brief Exercise Intervention on Resident Physician Personal Resiliency and Burnout: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Evaluation of a Daily Brief Exercise Intervention on Resident Physician Personal Resiliency and Burnout (NCT03489720), a randomized na study. The primary outcome is The Change in the Emotional Exhaustion (EE) Burnout Score(as Measured by the Maslach Burnout Inventory (MBI)From Baseline to End of Each Exercise Phase..

2. Clinical Question

The registry also describes broader aims: characterizing burnout and its predictors, and evaluating exercise in relation to burnout and personal resiliency. The primary outcome is specifically emotional exhaustion, not a direct measure of every aspect of burnout or resiliency.

The registry record does not report the numerical outcome results needed to judge the size or direction of any difference between exercise phases. It therefore does not establish from the posted results whether the primary question was answered in favor of either program, or how precisely any estimated difference was measured.

3. Trial Design

This was a randomized crossover study with no masking. The registry lists an enrollment of 46 and a completed study status. The study was sponsored by Vanderbilt University Medical Center. Its recorded start date is 2018-06-01, and its primary completion date is 2018-12-26. The phase is listed as not applicable.

Participants were assigned to one of two sequences. Arm A received 8 weeks of the exercise intervention followed by 8 weeks of the usual exercise program. Arm B received 8 weeks of the usual exercise program followed by 8 weeks of the exercise intervention. Thus, each sequence included both programs, with their order reversed. This arrangement can allow comparisons within participants, rather than relying only on comparisons between separate groups.

In a crossover study, the sequence and timing matter. Outcomes may change over time for reasons unrelated to the intervention, and an earlier phase could potentially influence a later phase. Random assignment of sequence can help balance order effects, but it does not by itself show how such effects were handled in the analysis. A washout period, if any, is not reported in the registry record. Nor is a statistical method for accounting for treatment period, sequence, or possible carryover reported.

The lack of masking means participants and study personnel were not masked to the assigned exercise program. That is relevant when interpreting a self-reported measure, because expectations or awareness of the program could influence reported responses. The record does not describe additional procedures intended to address this possibility. Although study completion is recorded, that status alone does not indicate whether the primary outcome was analyzed or what it showed.

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: Two participants were randomized to intervention arm followed by control arm. These participants withdrew from the study after the start of the intervention arm and never started the control arm.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Data was not available for analysis of baseline data for 1 participant in each exercise phase. Data was not available for analysis of change in MBI-EE for 2 participants in each exercise phase.

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 The Change in the Emotional Exhaustion (EE) Burnout Score(as Measured by the Maslach Burnout Inventory (MBI)From Baseline to End of Each Exercise Phase., measured over Baseline to 8 weeks.

The primary endpoint is the change in the Emotional Exhaustion score, or EE, on the Maslach Burnout Inventory Human Services Survey (MBI-HSS), from baseline to the end of each exercise phase. The registry gives a timeframe of baseline to 8 weeks and describes the outcome as a mean with standard deviation, measured in units on a scale.

The MBI-HSS EE component contains 9 items, each scored on a Likert scale from 0 to 6; the total EE score ranges from 0 to 54. The registry describes an EE score of at least 27 as a high degree of burnout and a score of 18 or lower as a low level. Emotional exhaustion is one dimension of professional burnout, so this endpoint captures a particular aspect of the broader construct rather than burnout in its entirety.

Change scores can describe how the measured score differs from baseline over a study phase. Their interpretation depends on the direction used to calculate change and on the size and uncertainty of the estimate. The registry record does not provide the numerical mean changes, standard deviations, or a between-program comparison. It is therefore not possible to describe the observed direction or magnitude of the primary endpoint from the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary endpoint is continuous: it is a score and its change, rather than a count of events or a time until an event. The registry describes the summary as a mean with standard deviation. A mean gives the average score or change in a group of observations. A standard deviation describes how spread out individual observations are around that average. Neither statistic is reported numerically for the primary outcome in the registry record.

What would a comparison estimate?

For this crossover question, the relevant estimate would compare emotional-exhaustion changes under prescribed exercise with changes under usual exercise. The comparison should be distinguished from describing change within either phase alone. A mean change in one condition indicates what happened between baseline and that phase’s end for the analyzed observations; it does not, on its own, identify how that change differs from the other condition.

In general, a crossover analysis may use the fact that participants experience both conditions, allowing a within-participant comparison. Such an approach can account for stable differences between participants. It still needs to consider whether responses vary by period or sequence, and whether an earlier condition might affect a later one. The registry record does not report the model or other method used for this primary comparison, so it is not possible to determine whether or how these features were addressed.

How should uncertainty be assessed?

A confidence interval is a range of values compatible with the observed data under the assumptions of the analysis. Its width conveys precision: a narrower interval indicates more precise estimation, while a wider interval indicates greater uncertainty. An interval for the between-condition contrast would help readers assess which effect sizes are consistent with the results. No such interval is reported for the primary outcome in the registry record.

A p-value, when reported, describes how compatible the observed data are with a specified null hypothesis under the analysis assumptions. It does not quantify the size or clinical importance of an effect. A p-value cannot substitute for the estimated contrast and its uncertainty. The registry record does not report a primary-outcome p-value or a stated significance threshold.

What does randomization contribute?

Random assignment of the two sequences can help reduce systematic differences in which order participants receive the exercise programs. It does not guarantee that all relevant features are balanced, and it does not eliminate missing outcome data, period effects, or measurement influences. Because masking was none, participants and study personnel knew the assigned program. The outcome is self-reported, so awareness could be relevant when considering possible measurement bias; the record does not describe how this was evaluated.

The study has two 8-week phases, but the registry does not report a washout period or a statistical plan for period, sequence, or carryover effects. Those details matter because an effect measured in a later phase could reflect more than the current program. This is a general consideration for crossover designs, not a claim that such an effect occurred in this study.

What can planning calculations tell readers?

Sample-size calculations are planning illustrations about the number of participants that might be needed under specified assumptions. They are not observed trial results and are not a measure of the study’s observed power. The assumptions described for planning include a two-sided significance level of 0.05, equal allocation between arms, a normal approximation, and a target effect expressed as a fraction of an observed effect. The registry record does not report numerical primary-outcome estimates from which to judge that observed effect, and no planning sample-size values are stated in the record. Such calculations cannot replace an effect estimate and its uncertainty.

Overall, the design and endpoint can be described, but the analysis cannot be independently interpreted from the registry record: the numerical estimates, uncertainty measures, and analysis method are not reported.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 9 outcome measures and no analysis entries. The primary endpoint is emotional exhaustion, but the record does not report a statistical plan describing which comparisons were primary, how secondary outcomes were handled, or whether any adjustment for multiple testing was intended. When many outcomes or comparisons are considered, the chance of at least one apparently notable result can increase. Adjustments and prespecified outcome hierarchies are possible ways to address that general issue, but the record does not say whether either was used.

Missingness is documented for the primary outcome. Baseline data were unavailable for analysis for 1 participant in each exercise phase. Data for change in MBI-EE were unavailable for 2 participants in each exercise phase. The record does not give reasons for these unavailable data or describe whether missingness was related to participant characteristics, study sequence, or observed scores.

The analysis population is not reported. The record does not say whether the primary analysis included all randomized participants, only participants with observed outcome data, or another defined group. It also does not specify an imputation method, a sensitivity analysis, or how observations from the crossover phases were paired or otherwise handled. These omissions limit assessment of whether missing outcome data could have influenced the estimated comparison. The participant counts described as unavailable apply to each phase; they should not be interpreted as a count of distinct individuals across phases.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry reports serious adverse events, other adverse events, and deaths separately for the two exercise conditions. For the Exercise Intervention group, 46 were listed as at risk, with 0 affected by serious adverse events, 0 affected by other adverse events, and 0 deaths. For the Usual Exercise Program group, 44 were listed as at risk, with 0 affected by serious adverse events, 0 affected by other adverse events, and 0 deaths. No top serious-event terms are listed.

These figures describe what was recorded in the registry. A zero count means no affected participants were reported for that category; it does not establish that the risk is absent or that no events occurred outside the registry’s reporting definitions or collection period. The record does not describe the event definitions, the safety observation windows, or whether events were collected in the same way across the crossover phases.

The at-risk figures are reported by condition and should be read as registry entries, not added together. Because this was a crossover study, the same participant may have contributed information under both conditions. The registry record does not provide enough detail to interpret these counts as independent group comparisons or to calculate comparative risks.

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

This record documents a randomized crossover evaluation of prescribed exercise and usual exercise, with emotional exhaustion measured at baseline and at the end of each 8-week phase. It establishes what the study set out to measure and how the two exercise sequences were arranged. It does not report numerical primary-outcome results, so it cannot establish the magnitude, direction, or precision of the primary comparison.

The absence of a reported estimate should not be read as evidence that the two programs had the same effect. It also does not support a conclusion that one program produced a better outcome. Those judgments require the condition-specific results and a comparison with an appropriate measure of uncertainty. The registry’s completed status is not a substitute for those results.

The endpoint measures emotional exhaustion through the MBI-HSS EE score. It does not by itself measure every aspect of professional burnout or personal resiliency. The broader aims described in the registry include burnout prevalence, predictors, and resiliency, but the primary endpoint cannot answer all of those questions. The record does not provide numerical findings for those broader aims either.

The safety entries report no affected participants for the listed serious-event, other-event, and death categories in either condition. These are registry counts, not proof that risk is absent. Interpretation is also constrained by the lack of reported details on safety definitions and observation periods.

Overall, the study record is informative about the randomized crossover design, the outcome scale, and some data availability and safety reporting. It is not sufficient to determine whether the exercise conditions differed on emotional exhaustion, whether any difference was statistically precise, or whether it was meaningful to participants. Such conclusions would require results and analysis details not reported in the registry record.

13. Why This Trial Matters Statistically

This trial raises several statistical issues that are important in clinical research. First, the crossover design gives each participant experience with both exercise conditions, but it makes timing and order central to interpretation. A treatment comparison must distinguish condition effects from changes associated with study period or sequence. The registry describes the sequence structure but does not report the analysis method used to handle it.

Second, the primary measure is continuous and based on self-report. Reporting only a conclusion, without the mean changes, variability, and between-condition estimate, would leave readers unable to judge the size and precision of the result. In this record, those numerical primary-outcome results are not reported at all. That makes the distinction between a planned question and an answer supported by posted data especially important.

Third, outcome availability is not complete in each phase. The record notes unavailable baseline data for 1 participant in each exercise phase and unavailable change data for 2 participants in each exercise phase. Without reasons for missingness or a description of the analysis population, readers cannot assess the potential influence of those unavailable observations.

Finally, the registry lists 9 outcome measures but no analysis entries. Without a reported analysis plan, readers cannot determine how multiple outcomes were prioritized or whether the primary comparison was prespecified in the form ultimately analyzed. These are not merely technical details: they affect how confidently results can be interpreted and compared with other studies. In this case, the registry record supports a description of the question and design, but not a statistical conclusion about the primary effect.

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 registry record leaves key details of this trial’s conduct and analysis unreported. It specifies randomized sequence assignment, no masking, and the two 8-week exercise phases, but does not describe a washout period or how potential period, sequence, or carryover effects were handled. These are specific interpretive concerns for a crossover design, particularly when outcomes are collected in successive phases.

The primary endpoint results are not reported numerically. Means, standard deviations, a between-condition estimate, uncertainty intervals, and p-values are absent from the record. Without these, the effect’s direction, size, and precision cannot be assessed. The record also does not describe the statistical model, analysis population, or treatment of missing outcomes.

Some baseline and change data were unavailable in each exercise phase, but reasons for unavailable data are not given. The self-reported emotional-exhaustion scale may also be affected by participants’ awareness of the exercise program, since masking was none; the record does not report methods for evaluating that possibility.

The record identifies the anesthesia residency at Vanderbilt University Medical Center as the study setting, but does not provide further details about participant characteristics that would help readers assess how broadly findings might apply. It lists broader aims concerning burnout and resiliency, yet the numerical results for those aims are not described. Finally, safety counts are reported without event definitions or observation-window details. These limitations concern what can be concluded from the registry record and do not establish that any particular bias or adverse effect occurred.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Evaluation of a Daily Brief Exercise Intervention on Resident Physician Personal Resiliency and Burnout — NCT03489720.
• Registry record last updated 2020-04-14; status last verified 2020-02.
• Results first posted 2020-04-14.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

The registry describes a completed, randomized crossover study of prescribed exercise and usual exercise among resident physicians in the anesthesia residency at Vanderbilt University Medical Center. One sequence received the prescribed program followed by usual exercise; the other received the programs in reverse order. Each phase lasted 8 weeks. Masking was none, and enrollment was listed as 46.

The primary outcome was change in the MBI-HSS Emotional Exhaustion score from baseline to the end of each phase. Baseline data were unavailable for analysis for 1 participant in each exercise phase, and change data were unavailable for 2 participants in each phase. The registry record does not report numerical primary-outcome results or the analysis method.

For safety, the registry lists 0 serious adverse events, 0 other adverse events, and 0 deaths for each condition. These counts should be interpreted within the limits of the safety details reported in the record.