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 Tofacitinib for the Treatment of Alopecia Areata and Its Variants (NCT02312882), a na na study. The primary outcome is Percent Change in Severity of Alopecia Tool (SALT) Score.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02312882 |
| Phase | NA |
| Condition | Alopecia Areata, Alopecia Totalis, Alopecia Universalis |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 40 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Stanford University |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned patients with moderate to severe alopecia areata and its variants. The conditions listed in the registry record are alopecia areata, alopecia totalis and alopecia universalis. Enrollment was 40. The record does not provide further participant characteristics or a more detailed description of the population included in the primary analysis.
Intervention
Participants received tofacitinib, described in the study summary as tofacitinib citrate and a Janus kinase inhibitor. The arm description says participants would receive tofacitinib for 3 months. The registry record does not report a dose or additional treatment details.
Comparator
There was no separate comparator group. The study model is listed as single group, and the record does not identify a control intervention. The baseline measurement in the primary outcome timeframe is not a concurrent control group: it is a reference point for describing change within participants.
Primary question
The registered primary endpoint was percent change in the Severity of Alopecia Tool (SALT) score from 0 to 3 months. The stated purpose was to investigate whether tofacitinib could generate hair regrowth in the study population. The registry record gives the endpoint and its planned summary format, but does not report the observed median percent change or its full range. Thus, the posted record does not show the primary outcome result needed to describe the amount or distribution of change.
3. Trial Design
This was a completed, single-group study sponsored by Stanford University. Enrollment was 40. The registry record lists the phase as NA, the allocation as NA, and masking as none. Its study model is single group, with tofacitinib as the only listed intervention. Participants were described as receiving treatment for 3 months.
The primary outcome timeframe was 0 and 3 months, which frames the endpoint as a change from the baseline assessment to the later assessment. The outcome was intended to summarize change in SALT score, rather than compare outcomes between separately assigned treatment groups. The registry record does not report a randomized allocation or a like-for-like control arm. Without such a comparison, changes over time cannot by themselves distinguish a treatment effect from other influences, including the natural course of the condition, differences in measurement, or events occurring during follow-up.
The study is marked completed, and its listed primary completion date is 2015-08. These registry entries describe the study’s recorded status and design; they do not establish that all enrolled participants completed follow-up or contributed to the primary analysis. The analysis population and the number with endpoint data are not reported in the registry record.
The primary outcome is listed as a median with full range. That choice can describe the central value and spread of participant-level changes without assuming that the distribution is symmetric. However, the posted results contain no primary outcome value or range, so the planned summary format cannot be used to assess the observed result. Information about protocol details, recruitment flow, treatment adherence and other design features is 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
| Stage | Tofacitinib |
|---|---|
| STARTED | 40 |
| COMPLETED | 36 |
| NOT COMPLETED | 4 |
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: Participants who completed the protocol are included in the analysis.
| Characteristic | Unit | Treatment Arm |
|---|---|---|
| Participants analysed | 36 | |
| Age, Continuous | years | 37 (19 to 65) |
| Sex: Female, Male: Female | Participants | 17 |
| Sex: Female, Male: Male | Participants | 19 |
6. Primary Endpoint
The registry lists the primary outcome as Percent Change in Severity of Alopecia Tool (SALT) Score, measured over 0 and 3 months.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Full Range |
| Unit | Percent change |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is percent change in the Severity of Alopecia Tool (SALT) score from 0 to 3 months. The registry record describes SALT as a scale ranging from 0, meaning no hair loss, to 100, meaning 100% hair loss. It also states that a positive percent change from baseline corresponds to a reduction in SALT score. That direction is important when reading the endpoint: a positive change is defined in relation to a lower score, not a higher one.
SALT provides a structured way to describe the extent of scalp hair loss. Summarizing change from baseline is useful because participants may begin with different levels of hair loss, and the endpoint focuses on movement relative to each participant’s starting assessment. The registry specifies the median and full range as the summary format. The median describes the middle of the observed values, while the full range describes the lowest and highest values; neither alone shows the detailed shape of the distribution.
The posted results do not report the median percent change or the full range. The endpoint definition therefore explains what the study intended to measure, but does not establish what changes were observed. No conclusion about the magnitude or consistency of change can be drawn from the endpoint description alone.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a clinically oriented question and a defined primary measure, but it does not provide the primary outcome result. Although the endpoint is specified as median percent change in SALT score over 0 and 3 months, the posted record contains no median value or full range. Consequently, the amount of change, its direction in the observed data, and the spread of participant responses are not available for interpretation.
This absence matters because a measurement definition is not a result. The description that positive percent change corresponds to a reduction in SALT score tells readers how to interpret the sign if a value is reported. It does not tell readers whether the observed median was positive, negative, or close to no change. Nor does the endpoint label itself show how many participants contributed data or whether changes varied substantially across participants.
The study has no separate comparator group. A change from baseline in a single group can describe what happened during the study period, but it does not isolate the effect of the intervention. General statistical interpretation: an uncontrolled before-and-after comparison is vulnerable to time-related changes and other influences that could coincide with treatment. Without a concurrent control group, the registry record cannot support a direct treatment-versus-control estimate.
The safety summary records 0 serious adverse events among 40 at risk in the treatment arm, and 18 participants affected in the other-adverse-event category among 40 at risk. These are distinct registry categories and should not be treated as a measure of efficacy. The deaths entry is not populated, so deaths are not reported in the registry record. The posted safety counts do not supply details about event types, timing, severity within the other category, or how events were collected.
The study is marked completed, but completion status does not fill the gap in outcome reporting. The registry record does not report an analysis population, participant-level endpoint availability, or reasons for missing measurements. It also does not report a protocol-level statistical plan, sample-size justification, interim analyses, or multiplicity strategy. Readers should therefore distinguish the known design and endpoint definitions from the unreported primary outcome and analysis details.
Overall, the posted record supports a description of what was planned and how some safety categories were tabulated. It does not support a numerical assessment of the primary outcome, a comparison with an alternative, or a causal conclusion about treatment. The most informative reading is that the primary result is unavailable in this registry record, rather than that the result was either favorable or unfavorable.
9. Statistical Methods Explained
The registry record describes a single-group study with a primary endpoint based on change from baseline. The outcome is reported in principle as a median and full range, but the observed summary values are absent. The following explanations are general statistical context for understanding this kind of design and summary; they do not fill in unreported analyses.
What does a single-group design estimate?
In a single-group study, outcome observations come from participants receiving the intervention, rather than from separately assigned intervention and control groups. A baseline assessment can provide a within-participant reference. The resulting change describes how measurements differ over time in the observed group. It is not the same as an estimate of how outcomes would differ between treatment and control under comparable conditions.
General statistical explanation: a causal treatment effect requires a basis for separating the intervention’s influence from other reasons outcomes might change. In a nonrandomized single-group design, factors such as natural history, concurrent events, participant expectations and measurement variation can contribute to observed change. Without a control group, those explanations cannot be separated using a direct between-group comparison.
Why summarize with a median and full range?
The median is a measure of the center of a distribution. It is less influenced by extreme values than the mean, which can make it useful when participant responses are skewed or include unusually large changes. The full range shows the smallest and largest observed values. It gives a sense of the overall span, but it is sensitive to the most extreme observations and does not describe how values are distributed between the endpoints.
General statistical explanation: a median and range provide only a compact description. They do not show every participant’s result, the frequency of particular response patterns, or the precision of the estimated center. A confidence interval, if reported, would describe uncertainty around an estimate under its statistical assumptions. The registry record does not report a confidence interval for the primary endpoint.
How should the endpoint direction be read?
The registry says that positive percent change from baseline corresponds to a reduction in SALT score. Since the score is described as ranging from 0 for no hair loss to 100 for 100% hair loss, the direction specified by the record is essential when interpreting a numerical change. This directional definition does not reveal the observed value. Because no primary result is posted, readers cannot use it to determine the actual direction or size of change in this study.
What can the safety counts tell us?
The safety table records participants at risk and participants affected in separate categories. General statistical explanation: a count gives the number recorded in a category, while the number at risk provides context for that count. A count does not describe event timing, duration, severity, recurrence or causal attribution. Those details require event-level information or additional summaries, which are not reported. The serious and other-adverse-event counts should remain distinct because the registry presents them as different categories.
What do the sample-size illustrations mean?
The sample-size section uses planning assumptions stated in the registry-derived details: a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. The stated method distinguishes total events for time-to-event tables from participants per arm for other illustrations. These are planning illustrations based on an observed effect, not the trial’s own design justification and not observed power.
General statistical explanation: a planning sample size is conditional on assumptions about the target effect, variability, allocation and statistical procedure. It describes a hypothetical design scenario, not what happened in this single-group study. The trial itself has no comparator arm, so a two-arm planning illustration should not be read as a description of its actual allocation or as evidence that its design had a particular probability of detecting an effect. The registry record does not report the study’s own sample-size justification.
No inferential test, adjusted estimate or confidence interval for the primary endpoint is reported in the registry record. Without those results, there is no basis to evaluate statistical uncertainty around the primary outcome estimate. More importantly, statistical precision would not resolve the design’s lack of a concurrent comparator: uncertainty around a within-group change and causal attribution are separate issues.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists one primary outcome measure and one analysis. It does not report a statistical analysis plan that would clarify which analyses were prespecified, how the primary endpoint was modeled, or whether any secondary or exploratory analyses were conducted. Details of interim analyses are not reported in the registry record.
Multiplicity concerns arise when several outcomes, time points, subgroups or analyses are tested or emphasized. General statistical explanation: examining many results can increase the chance that an apparently notable finding arises by chance, so an analysis plan may specify how to account for multiple comparisons. The registry information does not establish whether multiplicity adjustments were planned or used. The fact that one primary outcome measure is listed does not answer how other analyses, if any, were handled.
Missing-data information is also limited. The record does not state how many participants contributed SALT measurements at baseline or follow-up, how missing measurements were handled, or whether the primary analysis used all enrolled participants or a subset. Reasons for missing data and sensitivity analyses are not reported in the registry record. These details matter because an observed-case summary may represent a different participant set from the original enrollment.
The analysis population is not reported in the registry record. There is no basis to identify an intention-to-treat population, a per-protocol population or another defined group. The registry’s completed status does not establish complete follow-up or complete outcome data. These omissions limit assessment of selection and missing-data risks, independently of the absent primary outcome value.
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 |
|---|---|---|---|
| Treatment Arm | 0 | 40 | 0.0% |
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 |
|---|---|
| Treatment Arm | 18 of 40 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Treatment Arm |
|---|---|---|
| Upper respiratory tract infection | Respiratory, thoracic and mediastinal disorders | 4 of 40 |
| Abdominal pain | Gastrointestinal disorders | 2 of 40 |
| Acne | Skin and subcutaneous tissue disorders | 2 of 40 |
| Diarrhoea | Gastrointestinal disorders | 2 of 40 |
| Fatigue | General disorders | 2 of 40 |
| Headache | Nervous system disorders | 2 of 40 |
| Pruritus | Skin and subcutaneous tissue disorders | 2 of 40 |
| Conjunctivitis | Eye disorders | 1 of 40 |
| Cough | Respiratory, thoracic and mediastinal disorders | 1 of 40 |
| Dry eyes | Eye disorders | 1 of 40 |
The safety summary lists 40 participants at risk for serious adverse events and records 0 affected in that category. It also lists 40 participants at risk for other adverse events, with 18 affected. These are the counts shown for the treatment arm in the registry record. The record does not provide the names of the events in the other category, their timing, or their severity details. No serious adverse-event terms are listed.
The figures should be read as registry counts, not as a complete account of all possible safety information. A zero recorded count in the serious category does not establish that no event could occur, and the record does not describe the method or duration of safety surveillance. The deaths field is null; deaths are not reported in the registry record.
The other-adverse-event count is separate from the serious-adverse-event count. The record does not indicate whether an individual could have had more than one event, how events were attributed, or whether the count represents a particular event threshold. These data do not establish a comparison with another treatment because there is no separate comparator group.
12. What the Result Does, and Does Not, Mean
This study asks a relevant measurement question: how SALT scores changed from baseline during a 3-month course of tofacitinib in participants with moderate to severe alopecia areata and its variants. The registry record specifies the direction of the endpoint and the planned summary as median and full range. It also records safety counts for serious and other adverse events.
What the record does not show is the primary outcome result. There is no posted median percent change or full range, so readers cannot describe the amount, direction or variability of observed SALT change from this record. The endpoint definition alone cannot be taken as evidence that hair regrowth occurred or did not occur. The safety figures likewise do not establish whether the intervention caused or prevented any event.
The design also shapes what any within-group change could mean. Because the study is single group and has no concurrent control, change between baseline and follow-up would not by itself establish that the intervention caused the change. General statistical explanation: a comparator helps account for changes that might have happened over the same period without the intervention. Its absence leaves alternative explanations unresolved.
The findings that can be stated from the record are therefore limited to design, intended measurement, completion status and the reported safety counts. The study was marked completed, enrolled 40 participants, and listed treatment for 3 months. The registry record does not report the primary result, the analysis population, endpoint completeness or detailed statistical methods. These gaps prevent a full assessment of the outcome evidence.
This page should be read as an account of the registered study and the information posted for it, not as a clinical recommendation. It does not establish an effect estimate, a treatment comparison, or a complete profile of benefits and harms. Those questions require results and design details that are not reported in the registry record.
13. Why This Trial Matters Statistically
Statistically, this trial illustrates the difference between specifying an outcome and reporting its result. The registry record clearly identifies percent change in SALT score, the assessment timeframe, the score’s direction and the intended summary format. Yet the primary numerical result is not present. A precise endpoint definition helps readers know what was meant to be measured, but it cannot substitute for the observed estimate and its distribution.
The single-group design is also important. It can describe change within participants, but it does not offer a like-for-like control comparison. General statistical explanation: this distinction is central when moving from description to causal interpretation. A before-and-after pattern may be informative about what happened in the enrolled group, while leaving open what would have happened over the same period without the intervention.
The posted safety counts provide a separate example of why statistical summaries need context. The serious-event category records 0 affected among 40 at risk, while the other-event category records 18 affected among 40 at risk. Those counts are interpretable as registry entries, but the record does not give event terms or timing, and the deaths field is not reported. Counts do not independently explain event severity or attribution.
Finally, the absence of analysis-population and missing-data details limits assessment of who contributed to the outcome summary. Since the outcome summary itself is also absent, the record does not permit readers to assess either the result or its precision. Recognizing these boundaries is part of sound statistical reading: design, measurement, outcome reporting and uncertainty must all be considered, and none should be inferred from another.
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 principal limitation for interpreting this registry record is that the primary outcome result is not reported. Although the endpoint is defined as median percent change in SALT score with a full range, neither statistic appears in the posted results. The direction and magnitude of observed change therefore cannot be assessed.
The study has a single-group design with no concurrent comparator. Any within-group change would be unable, on its own, to separate intervention-related change from other influences over time. The registry record also lists no masking. It does not describe how outcome assessors were selected or whether measurement procedures included protections against assessment bias.
Participant flow and outcome availability are unclear. Enrollment was 40, but the number included in the primary analysis and the number with follow-up SALT measurements are not reported in the registry record. Reasons for missing measurements, methods for handling missing data, and sensitivity analyses are also not reported. As a result, the completeness and representativeness of any primary analysis cannot be evaluated from this record.
The registry does not report dose details, adherence, participant characteristics beyond the listed conditions, or a detailed statistical analysis plan. The sample-size justification, interim analyses and multiplicity approach are not reported in the registry record. Safety details are limited to category counts; event descriptions, timing and attribution are not given, and deaths are not reported in the registry record. These limitations are specific to the information and should not be mistaken for evidence that unreported procedures or analyses did or did not occur.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Tofacitinib for the Treatment of Alopecia Areata and Its Variants — NCT02312882.
- Registry record last updated 2017-11-06; status last verified 2017-10.
- Results first posted 2017-11-06.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
The registry record describes a completed, single-group study sponsored by Stanford University, with enrollment of 40. The listed conditions are alopecia areata, alopecia totalis and alopecia universalis. Participants received tofacitinib for 3 months; masking is listed as none, and allocation and phase are listed as NA.
The primary endpoint was percent change in SALT score from 0 to 3 months, summarized as median and full range. The record explains that positive percent change corresponds to a reduction in SALT score. The posted results do not report the primary outcome values or the analysis population.
Safety entries record 0 serious adverse events among 40 at risk and 18 affected in the other-adverse-event category among 40 at risk. Deaths are not reported in the registry record. No separate comparator group is listed, limiting the interpretation of within-group change as a treatment effect.