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 Tranexamic Acid in Adolescents With Heavy Menstrual Bleeding (NCT01846507), a na phase 4 study. The primary outcome is Change From Baseline Menses for Participant Perceived Blood Loss.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01846507 |
| Phase | Phase 4 |
| Condition | Heavy Menstrual Bleeding |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 32 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Nationwide Children's Hospital |
| Results posted | Yes |
2. Clinical Question
Population
Adolescent females with heavy menstrual bleeding were the intended population. The registry record does not report an age range or further eligibility details, such as how bleeding disorders were defined or whether they were required for enrollment.
Intervention
Participants received oral tranexamic acid, also called TA or Lysteda. The study description says it was taken during the first 5 days of menstrual bleeding. The treatment sequence began with a baseline menses without treatment, followed by 3 menses treated with tranexamic acid.
Comparator
The comparison was within one group: the untreated baseline menses was followed by treated menstrual cycles. There was no separate control arm or randomized comparison. A baseline-to-treatment comparison can describe changes over time, but it cannot separate treatment effects from other changes as directly as a concurrent control group can.
Primary question
The primary outcome asked whether participant-perceived blood loss changed from the untreated baseline menses across 3 menstrual cycles treated with tranexamic acid. It used Question 1 of the Menorrhagia Impact Questionnaire, scored from 1 for light blood loss to 4 for very heavy blood loss. Lower scores indicate less perceived blood loss. Numerical results for this outcome are not reported in the registry record.
3. Trial Design
NCT01846507, titled “Tranexamic Acid in Adolescents With Heavy Menstrual Bleeding,” is recorded as a completed Phase 4 study sponsored by Nationwide Children's Hospital. The registry lists 32 participants enrolled, with a start date of 2013-04 and primary completion in 2016-11. The condition is heavy menstrual bleeding.
This was a single-group study, not a randomized controlled trial. The registry records allocation as not applicable and masking as none. The treatment sequence consisted of a baseline menses without treatment followed by 3 menses using tranexamic acid. The study description says the drug was taken orally during the first 5 days of menstrual bleeding. Thus, the main comparison was between measurements from the same study group at baseline and during treated cycles, rather than between separately assigned treatment and control groups.
The study's stated aims included assessing safety and efficacy, learning how well tranexamic acid reduced menstrual blood loss, and asking whether participants and parents thought quality of life improved. The primary outcome was participant-perceived blood loss. Other listed outcomes covered perceived limitations in school attendance, physical activity, and social or leisure activities; menstrual blood loss measured by PBAC scores; hemoglobin; and ferritin. These additional measures broaden the clinical domains considered, but the registry record does not give numerical findings for them.
The design description establishes the order of the untreated baseline and treated menses, but does not report details such as the timing of outcome assessments within each cycle, adherence, or how incomplete observations were handled. Numerical primary-outcome results and analysis entries are not reported in the registry record. The design therefore supports describing the study question and its within-group comparison, but the available registry information does not support judging the size or precision of a measured change.
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: Baseline menses (no treatment) followed by 3 menses using tranexamic acid.
Overall Study
| Stage | Tranexamic Acid |
|---|---|
| STARTED | 32 |
| COMPLETED | 25 |
| NOT COMPLETED | 7 |
Reasons for not completing this period:
| Reason | Tranexamic Acid |
|---|---|
| Lost to Follow-up | 4 |
| Protocol Violation | 1 |
| Missing data | 2 |
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 | Tranexamic Acid |
|---|---|---|
| Participants analysed | 25 | |
| Age, Continuous | years | 14.7 (11 to 18) |
| Sex: Female, Male: Female | Participants | 25 |
| Sex: Female, Male: Male | Participants | 0 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 24 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 1 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 7 |
| Race (NIH/OMB): White | Participants | 14 |
| Race (NIH/OMB): More than one race | Participants | 3 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | Participants | 25 |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline Menses for Participant Perceived Blood Loss, measured over Baseline menses (no treatment) and 3 menstrual cycles treated with tranexamic acid.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Full Range |
| Unit | score on a scale |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was change from the baseline menses in participant-perceived blood loss. It was assessed using Question 1 of the Menorrhagia Impact Questionnaire, which asks about perceived blood loss during the most recent menses. The registry describes a score on a scale from 1 to 4: 1 represents light blood loss and 4 represents very heavy blood loss. Lower values indicate a more favorable outcome in the sense of less perceived blood loss.
This measure focuses on the participant's experience, rather than a laboratory estimate alone. Heavy menstrual bleeding can affect daily life, and a participant-reported measure can capture how bleeding is perceived. The registry also lists PBAC scores as a separate measure of menstrual blood loss, alongside hemoglobin and ferritin laboratory values and reported activity limitations. Those outcomes address related but distinct aspects of bleeding and its impact; they should not be treated as interchangeable with the primary questionnaire score.
The planned comparison was between the untreated baseline menses and 3 menses treated with tranexamic acid. The registry identifies the outcome and its scale but does not report the observed baseline or treated scores, the change estimate, a measure of uncertainty, or an analysis of the primary endpoint. As a result, the direction, magnitude, and precision of any change cannot be assessed from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a study intended to examine participant-perceived menstrual blood loss before and during tranexamic acid use. Its primary measure is understandable in direction: a lower Menorrhagia Impact Questionnaire score represents less perceived blood loss. However, the record does not report numerical primary-outcome findings. It gives no baseline score, treated-cycle score, change estimate, confidence interval, or test result. Consequently, the record does not establish whether the score changed, how large a change might have been, or how uncertain an estimate would be.
This is an important distinction between a registered research question and a reported result. The study's objective and planned outcome explain what investigators intended to evaluate; they do not themselves show an outcome. The listed secondary measures likewise identify domains of interest, including activity limitations, PBAC scores, hemoglobin, and ferritin, but their numerical results are not reported in the registry record. No conclusions about changes in those measures can be drawn from their names alone.
The single-group sequence also affects interpretation. Comparing an untreated baseline menses with later treated menses allows a within-group description, but the lack of a concurrent control group limits causal interpretation. Changes over time could reflect the intervention, natural variation between menstrual cycles, changes in other care or circumstances, or measurement variation. The registry does not report information that would allow those influences to be distinguished. This does not negate the value of recording change over time; it means the design offers less protection against alternative explanations than a randomized comparison with a control group.
The enrollment entry is 32, while the adverse-event record lists 30 at risk for its reported safety categories. Those are different registry entries and should not be silently treated as the same denominator. The record does not explain the difference. Nor does it provide outcome-specific analysis populations or details about missing observations. Without those details, readers cannot determine whether all enrolled participants contributed to each outcome or whether incomplete follow-up could affect estimates.
The registry lists zero analysis entries. This is not a numerical estimate of treatment effect, and it should not be read as evidence of no change. Rather, it means the registry record does not contain a posted analysis for the primary or secondary outcome measures in the information summarized. Any sample-size figures elsewhere are planning illustrations based on an observed effect, not the trial's original design or observed power. Since no numerical observed effect is reported in the registry record, those planning illustrations cannot substitute for a primary-outcome result.
9. Statistical Methods Explained
Statistical interpretation depends on what was measured, how observations were compared, and how much uncertainty surrounds an estimate. The registry identifies a within-group sequence: an untreated baseline menses followed by 3 treated menses. It does not report the statistical analysis used for the primary outcome, and no analysis entries are listed. The explanations below describe general statistical concepts, not methods confirmed to have been used in this study.
What does a within-group comparison show?
In a within-group design, observations from the same participants can be compared across time or conditions. This can be useful because each participant serves as a reference for their own earlier measurement. A change score can describe how measurements differ between baseline and follow-up. But without a separate concurrent control group, a change cannot by itself show that treatment caused the difference. Time trends, natural cycle-to-cycle variation, other changes in care, and measurement variability may also contribute.
The registry says the primary outcome covered the baseline menses and 3 treated menstrual cycles. Repeated measurements from one participant are generally related rather than independent. A statistical analysis should account for that relationship if it uses observations across multiple cycles. The registry does not report whether the analysis used individual cycle scores, an average across treated cycles, a change from baseline for each participant, or another summary. It also does not report how within-participant correlation was handled.
What does the scale mean for analysis?
The primary outcome is a questionnaire score on a 1-to-4 scale, with lower values indicating less perceived blood loss. A score on a bounded scale has a limited set of possible values, so its distribution may not behave like an unrestricted, normally distributed measurement. General approaches to such outcomes can include summaries of score distributions, methods for paired or repeated observations, or models suited to ordered categories. The appropriate choice depends on the data and analysis objective. The registry does not report which approach was selected.
A mean can provide a compact summary of a scale, but it does not reveal how scores are distributed across participants or whether changes were similar for everyone. A full range describes the lowest and highest observed values, but it does not, by itself, show where most observations lie. The endpoint description says the outcome parameter was a mean and dispersion was a full range; numerical values for those summaries are not reported. General statistical interpretation would benefit from both a clear estimate of change and information about its uncertainty and distribution.
How should uncertainty be understood?
General explanation: a confidence interval gives a range of values compatible with the data and the statistical model at a stated confidence level. It is not a guarantee that the true value lies in that particular interval, nor does it address bias from an unsuitable design or incomplete data. A narrow interval indicates greater statistical precision than a wide interval, but precision is not the same as clinical importance. The registry does not report a confidence interval for the primary outcome, so its precision cannot be assessed.
A p-value, when reported, describes how unusual the observed data would be under a specified null model and its assumptions. It does not measure the probability that the treatment works, and it does not quantify the size or importance of a change. No p-value or primary-outcome test result is reported in the registry record. Therefore, there is no basis in the record for describing the primary finding as statistically significant or not statistically significant.
What do the planning assumptions mean?
The sample-size planning illustration is described as using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It uses a stated fraction of the observed effect as the effect to detect. Those are planning assumptions for a hypothetical two-arm calculation; they do not describe the actual single-group study design, which had no randomized two-arm comparison. Such calculations illustrate how a future study's size could depend on the effect one wants to detect and the assumptions used. They are not observed power and do not show that this study had a particular probability of detecting an effect.
General explanation: over-dispersion occurs when the variability in outcome data is greater than a statistical model assumes. If ignored, uncertainty estimates may be too small and tests may appear more conclusive than warranted. Whether over-dispersion is relevant depends on the outcome and model. The registry does not report a fitted model or diagnostic checks, so no claim can be made about over-dispersion in this study.
For a clinical interpretation, an estimate of change, its uncertainty, the analysis population, and the handling of repeated and missing observations would all matter. Those details are not reported in the registry record. The posted information defines the endpoint and study sequence, but it does not provide the analysis needed to quantify the primary outcome.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary outcome and several additional outcomes, covering perceived limitations in school, physical, and social or leisure activities; PBAC scores; hemoglobin; and ferritin. Examining multiple outcomes can raise a multiplicity issue: when many hypotheses are tested, the chance of at least one apparently unusual result can increase. Statistical plans may address this through a prespecified hierarchy, adjustment procedures, or a clear distinction between primary and exploratory findings. The registry record does not report a multiplicity strategy, so it is not possible to tell whether or how testing across outcomes was controlled.
Missing data are also relevant to a study with repeated menstrual-cycle assessments. If participants lack one or more measurements, the analysis can depend on how those missing observations arose and how they were handled. For example, an analysis limited to participants with complete measurements may differ from one using a model that includes available repeated observations. These are general possibilities, not descriptions of this study's analysis. The registry does not report the amount or pattern of missing outcome data, the reasons for missingness, or any method used to address it.
The record lists 32 participants enrolled, but does not report analysis populations for the primary or secondary outcomes. It therefore does not establish which participants contributed to each outcome analysis. The adverse-event entries separately list 30 at risk; the record does not explain how that safety population relates to enrollment or to any efficacy population. The registry lists zero analysis entries, and numerical outcome analyses are not reported. Without a stated analysis population, missing-data approach, and multiplicity plan, readers cannot assess whether the posted record's outcome reporting reflects all planned analyses or how robust any estimate would be to alternative analytic choices.
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 |
|---|---|---|---|
| Tranexamic Acid | 1 | 30 | 3.3% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Tranexamic Acid | 0 of 30 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Tranexamic Acid | 23 of 30 |
Most frequent serious adverse event terms
| Event term | Organ system | Tranexamic Acid |
|---|---|---|
| Suicidal Ideation | Psychiatric disorders | 1 of 30 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Tranexamic Acid |
|---|---|---|
| Upper respiratory infection sypmtoms | Infections and infestations | 14 of 30 |
| Musculoskeletal pain | Musculoskeletal and connective tissue disorders | 9 of 30 |
| Fatigue | Reproductive system and breast disorders | 6 of 30 |
| Abdominal pain | Gastrointestinal disorders | 6 of 30 |
| Headache | General disorders | 5 of 30 |
| Dysmenorrhea | Reproductive system and breast disorders | 4 of 30 |
| Nausea | Gastrointestinal disorders | 3 of 30 |
| Heavy menses | Reproductive system and breast disorders | 2 of 30 |
| Anxiety | Psychiatric disorders | 2 of 30 |
| Fever | Infections and infestations | 2 of 30 |
Serious events with the highest arm-level rate: suicidal ideation (3.3%).
The safety record lists the Tranexamic Acid group with 30 at risk for serious adverse events and 30 at risk for other adverse events. It reports 1 serious adverse-event count and 23 other adverse-event counts, and lists 0 deaths. Suicidal ideation is named among the serious adverse-event terms, with a reported percentage of 3.3%. The registry does not provide further detail about timing, duration, severity beyond the serious classification, or the relationship of the event to treatment.
These entries should be read as descriptive safety reporting, not as a comparison with an untreated group. There was no separate control arm, so the record cannot establish whether the reported events occurred more or less often than they would have without treatment. The adverse-event at-risk entries also should not be assumed to equal the enrollment entry: the registry lists 32 enrolled, and the reason for the different safety denominator is not reported.
Counts alone do not establish causation. An event recorded during a study is not necessarily caused by the intervention. Conversely, a small number of reported events does not by itself establish that an intervention is free of risk. The registry record does not report a comparative safety analysis or enough context to evaluate event attribution. The figures describe what the record reports for the listed safety categories.
12. What the Result Does, and Does Not, Mean
This registry record is useful for understanding the study question, the treatment sequence, and the outcomes investigators intended to measure. It describes a single-group study in which an untreated baseline menses was followed by 3 treated menses, with participant-perceived blood loss as the primary outcome. The outcome scale has a clear direction: lower scores mean less perceived blood loss. These details help readers understand what a reported result would represent.
The record does not report numerical results for that primary outcome. Without observed scores or a change estimate, it cannot show whether participant-perceived blood loss changed, in which direction, or by how much. Without a confidence interval or other measure of uncertainty, precision cannot be assessed. The same caution applies to the listed secondary outcomes: their presence in the registry is not a report of their findings.
The study's single-group structure also limits what a change from baseline could mean. A difference between untreated and treated menses could be consistent with an intervention effect, but other explanations remain possible when there is no concurrent control group. The registry record does not provide enough information about other factors or analysis methods to separate those explanations.
The safety entries document reported adverse-event counts and identify suicidal ideation as a serious adverse-event term. They do not, by themselves, establish that the events were caused by tranexamic acid or permit comparison with an untreated group. The record also does not explain the difference between the enrollment entry and the safety at-risk counts.
Accordingly, the posted registry information supports a description of the clinical question and design, but not a conclusion about the size, reliability, or cause of a primary-outcome change. It also does not support a conclusion that the treatment is effective, ineffective, safe, or unsafe. Those judgments would require interpretable outcome estimates and suitable analysis, which are not reported in the registry record.
13. Why This Trial Matters Statistically
This study raises a useful statistical distinction between measuring change and establishing its cause. Repeating an outcome measure in the same group can show how participants' scores vary from an untreated baseline to later treated cycles. That structure can make participant-level change relevant to the research question. Yet, without a concurrent comparison group, it is difficult to separate treatment-related change from other influences over time. Recognizing this distinction helps prevent a within-group observation from being read as definitive evidence of a causal effect.
The primary endpoint also illustrates why outcome definitions matter. Participant-perceived blood loss is not the same measure as PBAC-assessed blood loss or laboratory values such as hemoglobin and ferritin. These measures can complement one another, but each captures a different aspect of the clinical question. Clear reporting of how each outcome was measured, summarized, and analyzed is essential for understanding what a result does and does not represent.
Repeated cycle measurements raise further methodological questions. Observations from the same participant may be related, and incomplete follow-up can affect which data contribute to an estimate. The registry record does not report the methods used to address these issues. It also does not report a multiplicity plan despite listing several outcomes. These omissions matter because analysis choices influence uncertainty and the interpretation of findings.
Finally, registry transparency is part of statistical interpretation. A stated endpoint and completed status are not substitutes for a posted estimate. Here, the record specifies what the investigators sought to assess but does not report numerical primary-outcome analyses. That boundary is important: readers can evaluate the design and identify the intended measure, while remaining appropriately cautious about conclusions that require results not reported in the registry record.
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 in interpreting this specific record is the absence of numerical results for the primary endpoint. Although the registry defines participant-perceived blood loss and its scale, it does not report the observed values, change estimate, or uncertainty. It also lists zero analysis entries. Without these results, the primary question cannot be answered from the registry record.
The single-group design has no concurrent untreated or alternative-treatment control arm. Comparing baseline and later cycles can describe within-group change, but it cannot reliably distinguish an intervention effect from cycle-to-cycle variation, changes over time, or other influences. The registry records no masking, so participants and investigators were not masked according to the entry. The record does not report whether this affected measurement or reporting of the participant-perceived outcome.
Other limitations include unreported eligibility details, analysis populations, adherence, missing-data patterns, and methods for repeated observations. The registry does not report how multiple outcomes were handled statistically, whether a prespecified analysis hierarchy existed, or whether any sensitivity analyses were conducted. These details are important for judging the reliability and interpretation of estimates, but cannot be inferred from the outcome list or study objective.
The safety record lists 30 at risk in each reported category, while enrollment is recorded as 32; the reason for that difference is not reported in the registry record. The safety entries are descriptive and have no control group for comparison. These limitations restrict what can be concluded about both efficacy and safety from the available registry information.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Tranexamic Acid in Adolescents With Heavy Menstrual Bleeding — NCT01846507.
- Registry record last updated 2018-10-24; status last verified 2018-09.
- Results first posted 2018-07-12.
- 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
NCT01846507 is a completed Phase 4, single-group study sponsored by Nationwide Children's Hospital, with 32 participants enrolled. The registry records a start date of 2013-04 and primary completion in 2016-11. Participants had an untreated baseline menses followed by 3 menses using tranexamic acid; the study description says the drug was taken orally during the first 5 days of menstrual bleeding.
The primary outcome was change in participant-perceived blood loss, measured with Question 1 of the Menorrhagia Impact Questionnaire on a scale from 1 to 4, where lower values indicate less perceived blood loss. The registry also lists activity, PBAC, hemoglobin, and ferritin outcomes. Numerical findings and analysis entries are not reported in the registry record. The safety record lists 30 at risk, 1 serious adverse-event count, 23 other adverse-event counts, and 0 deaths. The single-group design and absence of posted outcome estimates limit conclusions about treatment effects.