Adjuvant Therapy for Intrauterine Adhesions Between Two Groups: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Adjuvant Therapy for Intrauterine Adhesions Between Two Groups (NCT02867202), a randomized na study. The primary outcome is the AFS Score at Second-look Hysteroscopy.

2. Clinical Question

The trial is recorded as randomized, double-masked, and parallel-group. Its central comparison concerns two mechanical approaches used after surgical treatment of uterine adhesions. The primary outcome is an adhesion score assessed at a later hysteroscopy, not a direct measure of fertility, pregnancy, or another patient-centered outcome. Those outcomes are not reported in the registry record.

The posted medians were 6.5 for the intrauterine balloon group and 8.0 for the intrauterine device plus Foley catheter group. Because higher AFS scores indicate worse outcomes, the direction of these medians favors a lower score in the balloon group. The reported ranges overlap, and the registry record gives no confidence interval for the between-group contrast. The sponsor reports a two-sided t-test with p <0.05, but the record does not report a test statistic or an estimated difference.

3. Trial Design

The registry record describes a randomized, double-masked, parallel-group clinical trial comparing an intrauterine balloon with an intrauterine contraceptive device plus Foley catheter. The condition listed is Asherman syndrome. The interventions were used following hysteroscopic adhesiolysis, and the primary endpoint was assessed at second-look hysteroscopy after two or three months.

The record lists enrollment as 171 and status as completed. It gives the study start as 2015-06 and primary completion as 2017-12. The primary outcome results list 62 participants in the balloon group and 56 in the device-plus-catheter group. The registry record does not explain why the group counts reported for the outcome differ from the enrollment figure. It also does not describe how randomization was generated, how allocation was concealed, or what masking procedures were used.

The treatment descriptions specify different device schedules. The balloon was described as being removed on the 7th day after surgery. In the comparator group, the Foley catheter was removed after three days, while the intrauterine device was removed at the second hysteroscopy. The record says adhesions were judged again at that hysteroscopy. It does not report adherence, protocol deviations, or whether other aspects of care were standardized.

The registry record does not report a formal phase, a sample-size justification, or details of the planned statistical analysis beyond the reported two-sided t-test. It does not identify a primary analysis population or explain how missing outcome measurements were handled. These omissions make it difficult to assess the trial's prespecified analysis choices or to determine how closely the posted endpoint results reflect the originally intended analysis.

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: 1. not meeting inclusion criteria 2. declined to participate

Overall Study

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 AFS Score at Second-look Hysteroscopy, measured over 2 or 3 months after the surgery.

The primary endpoint is the AFS score at second-look hysteroscopy, assessed two or three months after surgery. The registry describes the score as based on the American Fertility Society classification of intrauterine adhesions, 1988 version. Its total scale runs from 0 to 12, with higher values indicating a worse outcome. The score therefore summarizes the severity of adhesions observed at follow-up, rather than measuring the experience of symptoms or a later reproductive outcome.

A follow-up hysteroscopy gives the study an opportunity to assess the uterine cavity after the initial adhesiolysis and after use of the assigned device. Using the same named score for both groups provides a common outcome for the randomized comparison. In general, a prespecified clinical score can make a complex finding easier to compare across groups, but interpretation depends on consistent assessment and on understanding what the score represents.

The registry reports medians and full ranges, rather than means and standard deviations, for the groups. The median is a measure of the middle of the observed score distribution; the range describes its lowest and highest reported values. The posted scores were 6.5, with a range from 1.0 to 10.0, in the balloon group and 8.0, with a range from 3.0 to 12.0, in the comparator group. These summaries do not show the full distribution or quantify uncertainty around the between-group difference.

The record does not report additional primary endpoints or patient-centered outcomes. It also does not describe who assessed hysteroscopy findings or whether outcome assessors remained masked. Those details matter when interpreting a scored visual assessment.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the reported p-value mean?

General: A p-value describes how compatible observed data are with a specified null hypothesis, under the assumptions of the statistical test. It is not the probability that the null hypothesis is true, and it does not state the probability that a result occurred by chance in a general sense. The registry reports p <0.05 from a two-sided t-test. This indicates that the reported test result crossed the threshold used in that report, but it does not convey the size or clinical importance of the group difference.

The registry does not provide the test statistic, degrees of freedom, exact p-value, or confidence interval. It also does not explain whether the t-test was applied to individual score values, transformed values, or another representation of the outcome. These details are not reported in the registry record, so the reported test cannot be fully evaluated from the posted summary.

Why distinguish medians from means?

General: A median identifies the middle of an ordered set of observations and is less affected by extreme values than a mean. A t-test is conventionally framed around a difference in means. The choice of descriptive summary and the choice of inferential test are not necessarily identical, but the record should ideally explain the estimand and analysis so readers can understand how they relate. Here, the outcome is reported using medians and full ranges, while the stated test is a t-test. The registry does not give enough detail to determine the precise relationship between these summaries and the test.

The group medians are 6.5 and 8.0, and the corresponding full ranges are 1.0 to 10.0 and 3.0 to 12.0. A range reports only the observed endpoints; it does not show how scores are distributed between those endpoints. It cannot, by itself, recover a standard deviation, standard error, or confidence interval. No such reconstruction is reported for this comparison.

What does randomization contribute?

General: Random assignment is intended to make treatment groups comparable, on average, with respect to both measured and unmeasured characteristics. It supports a causal comparison when the allocation process is implemented appropriately and participants are analyzed in a way consistent with the randomization. A registry label of randomized does not reveal the sequence-generation method, allocation concealment, adherence, crossover, or exclusions after assignment. Those implementation details are not reported in the registry record.

The study is also described as double-masked. General: Masking can reduce the influence of expectations on care, reporting, and outcome assessment. Its practical meaning depends on who was masked and whether the devices could be distinguished. The registry record does not identify the masked parties or describe how masking was maintained. This is particularly relevant for an outcome based on hysteroscopic assessment, because the record does not state whether the assessor was masked.

Why do confidence intervals matter?

General: A confidence interval gives a range of estimates compatible with the data and the method used, and communicates precision as well as direction. A narrow interval indicates greater precision than a wide interval, though interpretation also depends on the outcome and analysis. The registry does not report a confidence interval for the primary comparison. Without one, readers cannot assess the reported effect's precision from the inferential result.

The posted medians and ranges are useful descriptive statistics, but they do not substitute for an interval estimate of a group contrast. The registry also does not provide enough information to calculate such an interval independently. Any recalculated contrast from only these summary statistics would not be a valid substitute for the reported analysis.

What can be inferred from the reported test?

General: A statistically significant test result does not establish that an effect is large, important to patients, robust to different analytic choices, or free from bias. Interpretation requires the effect estimate, its uncertainty, the endpoint's clinical meaning, and knowledge of how the trial handled its participants and data. In this record, the reported p-value is accompanied by the endpoint summaries, but not by an effect estimate or confidence interval.

The registry does not report whether the test was adjusted for other variables, whether there were interim analyses, or whether multiple outcomes or comparisons were considered in the planned analysis. It also does not report a statistical analysis plan. Those aspects should not be inferred from the existence of a p-value or from the label of a test.

How should planning illustrations be read?

General: A sample-size calculation is a planning exercise that estimates how much information a future study may need under stated assumptions about the effect, variability, allocation, and error rates. It is not an observed trial result and does not establish the probability that this completed trial detected an effect. The registry's planning assumptions describe a two-sided significance level of 0.05, equal allocation, a normal approximation, and an effect defined as a stated fraction of the observed effect. The record does not report that these assumptions were the basis of the original trial design. A sample-size illustration based on an observed effect is retrospective planning context, not observed power.

10. Analyses Reported by the Sponsor

The registry reports the sponsor's comparison as a two-sided t-test with p <0.05. The posted endpoint summaries are medians and full ranges, but the record does not include the test statistic, a confidence interval, or sufficient information to reconstruct the test from those summaries. No recalculated estimate or p-value is therefore reported for this comparison.

The sponsor's reported test is the inferential result available in the registry record. Its interpretation should remain tied to the analysis as reported: the test crossed the stated significance threshold, while the size and precision of the contrast are not quantified in the record. The lower posted median in the balloon group describes the direction of the group summaries; it is not an independent reanalysis and should not be substituted for the sponsor's test.

The record does not explain the analysis population, assumptions, or exact implementation of the t-test. It also does not report an estimated between-group difference or interval around that estimate. Readers therefore cannot use the posted summaries alone to verify the sponsor's inferential result or to judge its precision. The registry does not report a discrepancy between the sponsor analysis and a recalculation; a recalculation is not available from the information recorded.

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists one primary outcome measure and one reported analysis. It does not report secondary outcomes. However, the record does not describe the prespecified statistical analysis plan, whether other outcomes or comparisons were planned, or whether the reported test was selected before examining the data. It is therefore not possible to determine from the registry whether multiplicity was considered or whether any adjustment was planned.

General: When several outcomes, time points, or comparisons are tested, the chance of at least one apparently significant result can increase. Methods for handling multiple tests depend on the study's objectives and the planned family of comparisons. The absence of a reported adjustment does not show that an adjustment was required or omitted; it means the registry record does not provide that information.

The primary outcome group summaries list 62 participants for the balloon group and 56 for the device-plus-catheter group. The enrollment figure is 171. The registry does not explain why these figures differ, identify the number randomized to each group, or state whether the outcome counts represent everyone randomized, everyone treated, or only participants with an observed second-look score. Reasons for any unreported endpoint results are not given.

Missing-data handling is not reported in the registry record. There is no description of imputation, complete-case analysis, sensitivity analysis, or how participants without a second-look hysteroscopy were handled. The registry also does not identify an intention-to-treat or per-protocol analysis population. These omissions limit assessment of possible bias from incomplete follow-up and prevent a clear account of which participants contribute to the reported comparison.

The sample-size justification and original statistical plan are not reported. A planning illustration based on a fraction of the observed effect, even when presented with stated assumptions, cannot establish what the trial was designed to detect or how its original enrollment target was chosen.

12. Safety Results

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

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 2.3% reporting threshold.

Most frequent non-serious adverse event terms

The registry reports zero serious adverse events in the intrauterine balloon group, with 83 participants at risk, and zero in the intrauterine device plus Foley catheter group, with 88 participants at risk. It also reports zero deaths in each group. These figures are the serious-event and death counts recorded for the listed safety groups.

The registry lists other adverse events separately: 21 among 83 at risk in the balloon group and 32 among 88 at risk in the device-plus-catheter group. These are not identified as serious adverse events in the record. The outcome group counts for the primary AFS analysis differ from the safety-group counts, and the registry does not explain the difference or describe the safety observation period.

Zero recorded serious events should be interpreted as a statement about the events reported in this record, not as proof that no serious events occurred outside the recorded safety assessment. The record does not provide event definitions, severity criteria, event timing, or a detailed account of collection and follow-up. It also does not report serious-event terms beyond the zero counts. The available figures therefore describe what was posted, but do not support a comprehensive comparison of safety across all possible outcomes or follow-up periods.

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

The registry reports lower median AFS scores for the intrauterine balloon group than for the intrauterine device plus Foley catheter group at second-look hysteroscopy. Because higher scores represent worse adhesion outcomes, the direction of the medians is consistent with lower recorded adhesion severity in the balloon group. The sponsor's reported two-sided test has p <0.05. The record does not provide an effect estimate or confidence interval, so the magnitude and precision of the group contrast are not established by the posted inferential results.

This result concerns a score assessed at the follow-up hysteroscopy described in the registry. It does not show whether the groups differed in fertility, pregnancy, symptoms, quality of life, later procedures, or other outcomes, none of which are reported as results in this record. Nor does the reported test, by itself, establish that any score difference is clinically important.

The record identifies the trial as randomized and double-masked, but does not describe key implementation details, the masked parties, or outcome-assessor masking. The analysis population and missing-data methods are also not reported. These uncertainties affect how confidently the posted group comparison can be interpreted as an unbiased estimate of the effect of assignment.

The observed summaries should not be treated as proof that one device is superior in every setting or for every outcome. The registry record does not report enough information to assess the reproducibility of the result, its longer-term implications, or its applicability to populations beyond those studied. It supports a focused description of the AFS scores and the sponsor's test, with important limits on conclusions about effect size, precision, and broader clinical consequences.

14. Why This Trial Matters Statistically

This trial is statistically notable because its primary outcome is reported as medians and ranges, while the registry identifies a two-sided t-test as the analysis. Both kinds of information can be useful, but they answer different descriptive and inferential questions. Without the test statistic, an effect estimate, a confidence interval, or details about the analysis, readers cannot connect the reported test fully to the summarized score distributions.

The endpoint also illustrates the distinction between a clinical measure and a broader clinical outcome. The AFS score provides a structured assessment of adhesions at a later hysteroscopy, and the record defines the direction of the scale. That makes the posted medians interpretable in direction. It does not establish whether a given score difference predicts outcomes that matter beyond the assessed adhesion score.

The record contains a randomized, double-masked design description, but it does not report how randomization or masking was implemented. It does not identify the primary analysis population or explain the difference between enrollment and the outcome counts. These are central details for evaluating whether randomization was preserved in the analysis and whether missing outcome data could influence the comparison.

Finally, the sponsor's reported p-value is not accompanied by an estimate of uncertainty or an account of the analysis plan. This illustrates why a threshold-crossing p-value should not stand alone: interpretation also depends on effect size, precision, endpoint meaning, and trial conduct. The registry record offers a limited but useful snapshot of a specific randomized comparison, while leaving those important statistical questions unresolved.

15. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The registry record does not report a numerical estimate of the between-group effect or a confidence interval for the AFS comparison. The posted medians and full ranges summarize the outcome but do not show the complete score distributions. The reported t-test cannot be independently reconstructed from those summaries, and the exact application of the test is not described.

Enrollment is listed as 171, while the primary outcome groups list 62 and 56 participants. The record does not explain this difference, state how many participants were assigned to each group, or describe whether outcome data were missing. It does not report the analysis population, reasons for missing second-look scores, or methods for handling missing results. This limits assessment of follow-up completeness and potential bias.

The record describes the study as randomized and double-masked but does not give details of sequence generation, allocation concealment, masking procedures, or who assessed the hysteroscopy outcome. It does not report protocol adherence, crossovers, or other deviations from assigned treatment. Such information would help readers evaluate implementation of the design.

The statistical analysis plan, sample-size justification, and any interim analyses are not reported. The record does not explain whether adjustment for multiple testing was considered. It also reports no secondary outcomes, so the comparison cannot be placed alongside other clinical outcomes in this trial.

Safety reporting is limited to the listed counts. Event definitions, timing, severity criteria, and duration of safety follow-up are not reported. The outcome is an AFS score at second-look hysteroscopy after two or three months; longer-term adhesion outcomes and reproductive outcomes are not reported. These limitations constrain conclusions about both the statistical reliability and the broader clinical meaning of the result.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Adjuvant Therapy for Intrauterine Adhesions Between Two Groups — NCT02867202.
• Registry record last updated 2020-01-02; status last verified 2019-12.
• Results first posted 2020-01-02.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

19. Record Summary

NCT02867202 is a completed randomized, double-masked, parallel-group trial of an intrauterine balloon versus an intrauterine contraceptive device plus Foley catheter after hysteroscopic adhesiolysis for intrauterine adhesions. The registry lists enrollment as 171, a study start of 2015-06, and primary completion of 2017-12.

The primary outcome was the AFS score at second-look hysteroscopy, two or three months after surgery. Median scores were 6.5, range 1.0 to 10.0, for the balloon group and 8.0, range 3.0 to 12.0, for the device-plus-catheter group. Higher scores indicate worse outcomes. The reported two-sided t-test has p <0.05.

The registry does not report a confidence interval, effect estimate, analysis population, missing-data method, or detailed statistical plan. Safety results list zero serious adverse events and zero deaths in both groups.