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 Pharmacogenomics of the Variability in the In Vivo Response to Glucocorticoids (NCT03023891), a na phase 1 study. The primary outcome is White Blood Cell Counts.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03023891 |
| Phase | Phase 1 |
| Condition | Glucocorticoids Toxicity, Glucose Intolerance |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 25 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Vanderbilt University Medical Center |
| Results posted | Yes |
2. Clinical Question
The study asks how white blood cell counts and glucose tolerance change after acute prednisone administration in healthy volunteers, and whether these measures are related to changes in gene expression. The primary outcome named in the registry is white blood cell count, measured at baseline and within 4 to 8 hours after drug administration. The registry summary also describes glucose tolerance and gene expression as study measures.
Population
Healthy volunteers enrolled in a Phase 1 study. The registry lists an enrollment of 25. It does not report further characteristics of the analyzed participants or describe a specific subgroup for the primary outcome.
Intervention
Each participant was to receive a single oral dose of 60 mg of prednisone. The arm description places administration at 7am and describes subsequent measurements at Visit 2.
Comparator
The study is recorded as a single-group design with allocation listed as NA and no masking. Baseline measurements precede prednisone, but the registry does not describe a separate placebo or untreated control group.
Primary question
What white blood cell counts were recorded at baseline and within 4 to 8 hours after prednisone, and how do the posted measurements describe the short-term change? Numerical results for this endpoint are not reported in the registry record.
This is therefore a before-and-after question within a treated group, not a randomized comparison between prednisone and a control treatment. The stated interest in associations with gene expression is part of the study summary, but the registry record does not report those analyses or their results.
3. Trial Design
The registry classifies this as a Phase 1, completed, single-group study with no masking. Allocation is listed as NA. Vanderbilt University Medical Center is identified as the sponsor. The record lists enrollment of 25 and a study start date of 2017-02-15, with primary completion on 2019-01-10.
The intervention is oral prednisone. The arm description specifies a single 60 mg dose at 7am. Visit 1 included a baseline oral glucose tolerance test and white blood cell count. Visit 2 included prednisone administration and describes glucose tolerance and white blood cell measurements at 4 to 8 hours after the drug. The primary endpoint timeframe is also described as baseline and within 4 and 8 hours after administration. The record does not clarify whether measurements were planned at both 4 and 8 hours for every participant or how timing varied within that interval.
Because this is a single-group study, baseline is a within-participant reference rather than a parallel control arm. That structure can describe changes following administration, but by itself does not separate a drug-related change from other time-related influences. The registry does not report a detailed protocol or a statistical analysis plan, so the intended approach to repeated measurements and any adjustment for covariates is not reported in the registry record.
The summary names white blood cell count, glucose tolerance, and gene expression as study measures. Four outcome measures are recorded, but the registry record does not provide the full definitions and results for all of them in the information available for this analysis. It reports no statistical analyses. Consequently, the design and measurement schedule can be described, but the actual analyzed sample, endpoint estimates, and inferential results cannot be reconstructed from 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.
Before assignment: 25 participants signed consent, 5 did not show up for screening and 2 failed screening. 18 participants started the study.
Overall Study
| Stage | Prednisone |
|---|---|
| STARTED | 18 |
| COMPLETED | 18 |
| NOT COMPLETED | 0 |
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.
| Characteristic | Unit | Prednisone |
|---|---|---|
| Participants analysed | 18 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 18 |
| Age, Categorical: >=65 years | Participants | 0 |
| Sex: Female, Male: Female | Participants | 9 |
| Sex: Female, Male: Male | Participants | 9 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 17 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 2 |
| Race (NIH/OMB): White | Participants | 14 |
| Race (NIH/OMB): More than one race | Participants | 2 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 18 |
6. Primary Endpoint
The registry lists the primary outcome as White Blood Cell Counts, measured over baseline and within 4 and 8 hours after drug administration.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | x10^3 cells/mL |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is white blood cell count, expressed in x10^3 cells/mL. The registry identifies the outcome as a continuous measure summarized by a mean and standard deviation. It describes measurement at baseline and within 4 to 8 hours after prednisone administration; the timeframe wording also refers to measurements within 4 and 8 hours.
White blood cell count is included as a short-term response measure in this study of acute glucocorticoid administration. Comparing a participant's post-dose measurement with their baseline measurement can describe how the measured count changes over the stated interval. The registry summary frames this measure alongside glucose tolerance and gene expression, but it does not state a more detailed rationale for selecting it as the primary endpoint. Any broader biological interpretation would require evidence beyond the endpoint definition.
The registry record does not report the baseline or post-dose means, standard deviations, sample sizes used for the endpoint, or an estimated change. It also does not report a confidence interval, p-value, or analysis method for the primary endpoint. Thus, the endpoint's measurement plan is described, but the magnitude and precision of any observed change are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a short-term, within-participant study of oral prednisone and names white blood cell count as the primary outcome. It does not include numerical endpoint results or any reported statistical analyses. There is therefore no posted mean at baseline or after treatment to interpret, and no reported estimate of change to describe as larger, smaller, or consistent with no change.
The registry lists 25 participants enrolled, but enrollment alone does not establish how many contributed data to the primary endpoint. The analyzed sample size and reasons for any difference between enrollment and analysis are not reported in the registry record. Likewise, the posted material available for this analysis does not include standard deviations, confidence intervals, or p-values for the endpoint. Without those quantities, the precision of an estimate and the compatibility of the data with alternative effect sizes cannot be assessed.
General statistical interpretation: a mean describes the central value of a continuous measure, while a standard deviation describes variation among individual measurements around that mean. A confidence interval, when reported, communicates uncertainty around an estimated quantity under the assumptions of the analysis. These summaries answer different questions; neither can be inferred from the enrollment count or the endpoint definition alone.
The single-group structure also matters. A comparison of measurements before and after dosing can characterize temporal change among participants, but it is not a randomized comparison with a concurrent placebo or untreated group. Changes over the same period could reflect influences other than the intervention. The registry record lists no allocation to a control group and does not report a method for accounting for such influences.
The study summary describes an interest in the relationship between white blood cell counts, glucose tolerance, and gene expression. The registry record does not report the results of those relationships, so no direction, strength, or statistical certainty can be stated. It also does not report whether the primary outcome was analyzed at a particular post-dose time or through a combined repeated-measures analysis. The appropriate reading is consequently limited to the stated design and outcome plan: numerical evidence of the size or precision of any response is not reported in the registry record.
9. Statistical Methods Explained
The registry specifies a continuous primary outcome, a mean as the summary parameter, and standard deviation as the dispersion measure. It does not report the statistical test, model, adjustment strategy, or estimate used to analyze white blood cell counts. Statistical concepts below are general explanations, not descriptions of analyses confirmed in the registry record.
What does a mean and standard deviation describe?
General: the mean gives a central summary of measured values. The standard deviation describes how spread out individual values are around that mean. A mean change and the spread of individual changes are not interchangeable: participants can have different responses even when the group average is modest. The registry names these summaries for the primary outcome but does not report their numerical values.
Why does the single-group structure affect interpretation?
General: when the same participants are measured before and after an intervention, the two measurements are related. A paired analysis accounts for this within-person relationship by focusing on each participant's change. Treating the observations as if they came from unrelated groups would ignore that pairing and can misrepresent uncertainty. The registry describes baseline and post-dose measurements, but it does not state whether the analysis used paired changes, a repeated-measures model, or another approach.
A within-person comparison also has a limited causal interpretation. It can describe how measurements differ over time among the enrolled participants, but without a concurrent comparison group it cannot by itself distinguish the intervention's contribution from other changes that occur over time. This is a general feature of before-and-after designs, not a finding about the participants in this study.
What would uncertainty measures add?
General: a confidence interval gives a range of values that are compatible with an estimate under the model and its assumptions. Its width reflects precision; a narrower interval generally indicates more precise estimation than a wider interval. A p-value addresses compatibility with a specified null hypothesis under a statistical model. It does not measure the size or clinical importance of an effect. Neither type of result is reported for the primary endpoint in the registry record, so no inferential conclusion can be drawn from them.
How should repeated timing be handled?
The primary timeframe refers to baseline and measurements within 4 and 8 hours after administration, while the arm description gives a post-dose window of 4 to 8 hours. General: if measurements are taken at multiple post-dose times, an analysis can estimate time-specific changes or model the pattern over time. Such an analysis should account for the fact that measurements from the same participant are correlated. The registry does not report how the timing descriptions were operationalized, whether every participant had measurements at both stated times, or how the repeated observations were modeled.
What can be said about planning calculations?
The registry's stated planning framework describes a normal approximation, two-sided significance level of 0.05, and equal allocation between two arms, with planning based on fractions of an observed effect. That framework does not match the recorded single-group, before-and-after design as described. No numerical planning results are reported in the registry record for this analysis, and no observed endpoint effect is reported from which to assess such calculations. General: a sample-size illustration is a planning calculation under assumptions, not evidence that a study had a particular probability of detecting an effect after the data were observed. The registry does not report its original sample-size justification.
The registry lists four outcome measures and zero reported analyses. It does not specify an analysis population, a missing-data method, or an approach to multiplicity. These omissions prevent assessment of how the planned endpoint and other measurements were incorporated into statistical inference.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies four outcome measures and names white blood cell count as the primary outcome. It does not report the full analysis plan for the other measures, the number of hypotheses tested, a hierarchy among outcomes, or any adjustment for multiple comparisons. The registry record lists zero analyses. Accordingly, multiplicity handling is not reported in the registry record.
General: when several outcomes, time points, or relationships are examined, the chance of at least one apparently unusual result can increase if each is assessed separately without accounting for the number of analyses. A prespecified primary endpoint and a defined testing strategy can help readers distinguish confirmatory analyses from exploratory ones. The registry's designation of a primary endpoint does not, on its own, show how other comparisons were handled.
The analyzed population is also not described. Enrollment is 25, but the number contributing to each outcome, exclusions after enrollment, and analysis-set definitions are not reported in the registry record. Missing-data procedures, including whether incomplete repeated measurements were retained or excluded, are not reported. No imputation method or sensitivity analysis is described.
These gaps do not establish that data were missing or that multiple testing occurred; they mean the registry record does not give enough information to assess either issue. Without analysis populations, missing-data handling, and a multiplicity strategy, readers cannot determine how those choices may have affected estimates or uncertainty.
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 |
|---|---|---|---|
| Prednisone | 0 | 18 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Prednisone | 0 of 18 |
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 |
|---|---|
| Prednisone | 4 of 18 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Prednisone |
|---|---|---|
| Diarrhea | Gastrointestinal disorders | 1 of 18 |
| Mild Dizziness | General disorders | 1 of 18 |
| Mild anxiety and hyperactivity | General disorders | 1 of 18 |
| Tiredness, Fatigue | General disorders | 1 of 18 |
| Dehydration | General disorders | 1 of 18 |
The registry reports safety figures for the Prednisone group with 18 participants listed as at risk for serious adverse events and 18 listed as at risk for other adverse events. It records zero serious adverse events, four participants affected by other adverse events, and zero deaths. No specific serious adverse event terms are listed in the registry record.
These counts should be read with their reported denominators rather than assumed to represent all 25 enrolled participants. The registry does not explain the difference between the enrollment count and the 18 participants listed as at risk, or provide further details about the safety population. It also does not report the types, severity, timing, or relatedness of the four other adverse events in the registry record for this analysis.
General: adverse-event counts describe recorded events or affected participants under the registry's reporting categories; they do not, by themselves, establish causation. The zero serious adverse events and zero deaths are the posted counts for the listed safety group, not proof that no such events could occur. These figures are descriptive and should not be used to make treatment decisions.
12. What the Result Does, and Does Not, Mean
The registry record documents a completed Phase 1 study designed to measure white blood cell count and glucose tolerance before and after a single oral prednisone dose in healthy volunteers, with gene expression also named in the study summary. It establishes the study's broad question and measurement schedule, but it does not report numerical primary outcome results or statistical analyses.
As a result, the record does not establish the size or direction of a change in white blood cell count, how much individual responses varied, or how precise an estimated change might be. It also does not report findings on glucose tolerance or the relationship of any measure to gene expression. None of those results can be inferred from the study design, enrollment count, or completion status.
The single-group, before-and-after design can be used to describe changes over the measurement period among participants who were studied. Without a separate control group, such a change would not by itself isolate the contribution of prednisone from other time-related influences. This is a design limitation, not evidence that a particular alternative explanation occurred.
The safety record lists zero serious adverse events and zero deaths among 18 participants at risk, with four listed as affected by other adverse events. These are descriptive registry counts; details about the other adverse events and the safety population are not reported in the registry record.
The results therefore support a narrow reading: the registry documents the planned and completed study framework, while the outcome evidence needed to quantify a response is not reported. The record does not support a conclusion about the magnitude, precision, or broader applicability of any effect.
13. Why This Trial Matters Statistically
This study is statistically informative as an example of how a research question and an analysis result are different kinds of evidence. The registry gives a specific short-term measurement plan and identifies white blood cell count as the primary outcome. Yet it reports zero analyses and no numerical outcome estimates in the record. A defined endpoint is not a substitute for posted data.
The design also highlights the distinction between within-person change and a controlled treatment comparison. Baseline measurements can provide a reference for post-dose measurements in the same participants. That structure is suited to describing observed temporal change, but it does not supply the same protection against time-related influences as a concurrent randomized comparison. The interpretation must follow the design rather than imply a stronger comparison than was conducted.
The registry's planning framework is described in terms of two equal-allocation arms, whereas the trial is recorded as a single group. This mismatch illustrates why planning assumptions should be checked against the study design before interpreting sample-size calculations. No numerical planning output or observed effect is reported in the record available for this analysis.
Finally, the enrollment and safety counts use different reported totals, and the registry does not explain the analysis populations or missing-data handling. Such details matter because estimates depend on which participants and measurements contribute. The record is useful for understanding the intended question and broad design, but its statistical conclusions remain limited by the absence of reported endpoint analyses.
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 primary limitation for interpretation is that numerical results for white blood cell count are not reported in the registry record. Baseline and post-dose means, standard deviations, estimated changes, confidence intervals, and p-values are not available in the registry record for this analysis. The registry lists zero analyses, so the magnitude and precision of any observed response cannot be assessed.
The study is recorded as single-group, with allocation listed as NA and no masking. There is no described concurrent control group, so a before-and-after difference would not by itself separate intervention-related change from other influences over time. The registry does not report a detailed protocol or the statistical method used for repeated measurements.
Although the registry lists enrollment of 25, it lists 18 participants at risk in each safety category. The record does not explain the difference, identify the number analyzed for the primary endpoint, or describe exclusions, withdrawals, or missing observations. Those details are not reported in the registry record.
The endpoint timing is described both as within 4 to 8 hours and as within 4 and 8 hours. The record does not clarify the exact measurement schedule or how variation in timing was handled. It also names glucose tolerance and gene expression in the study summary without reporting the corresponding analyses or results.
Finally, the statistical analysis plan, sample-size justification, multiplicity strategy, and missing-data approach are not reported. These limits constrain interpretation of both the intended analyses and the reported safety figures; they do not establish that any specific analysis or data problem occurred.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Pharmacogenomics of the Variability in the In Vivo Response to Glucocorticoids — NCT03023891.
- Registry record last updated 2020-06-04; status last verified 2020-05.
- Results first posted 2020-01-06.
- 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
NCT03023891 is a completed Phase 1, single-group study sponsored by Vanderbilt University Medical Center. The registry lists enrollment of 25, a start date of 2017-02-15, and primary completion on 2019-01-10. The study summary describes acute oral prednisone administration in healthy volunteers and examines white blood cell counts, glucose tolerance, and gene expression.
The primary outcome is white blood cell count, measured at baseline and within 4 to 8 hours after a single oral 60 mg prednisone dose. The registry reports no statistical analyses and does not report numerical primary outcome results. Safety figures list 18 participants at risk, zero serious adverse events, four affected by other adverse events, and zero deaths; details about the safety population and other adverse events are not reported in the registry record.