SIS Versus Office Hysteroscopy for Uterine Cavity Evaluation Prior to IVF: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for SIS Versus Office Hysteroscopy for Uterine Cavity Evaluation Prior to IVF (NCT04415489), a randomized na study. The primary outcome is Patient Satisfaction.

2. Clinical Question

3. Trial Design

The registry describes NCT04415489 as a completed randomized, parallel-group trial with no masking. The listed enrollment is 100. The comparison was between office hysteroscopy and SIS, with 50 participants recorded in each arm for the primary satisfaction outcome. The trial concerned uterine cavity evaluation before IVF among people with infertility. Its title identifies the comparison as SIS versus office hysteroscopy, while the outcome record lists office hysteroscopy as the control group for the mean difference.

The registry gives a study start date of 2019-12-06 and a primary completion date of 2020-12-01. The phase is listed as NA. The sponsor is the University of North Carolina, Chapel Hill. The brief summary explains that hysteroscopy was regarded by the investigators as the diagnostic gold standard for intra-uterine pathology, but that provider concerns about tolerability in the office, operating room costs, and anesthesia limited its use as an initial screening tool. Those statements describe the study rationale, not results establishing how the procedures compare on all relevant clinical outcomes.

The stated aims extended beyond satisfaction. Investigators also aimed to assess whether office hysteroscopy could manage intra-uterine pathology at diagnosis and reduce delays and additional procedures. The secondary outcomes include procedure completion time, participants requiring a secondary procedure, time to infertility treatment, positive predictive value of SIS, and ability to manage pathology with office hysteroscopy. The registry lists nine outcome measures and six analyses, but not every outcome’s results or analysis details are available in the record summarized by these results.

Masking is recorded as none. The registry record does not report details of the randomization sequence, allocation concealment, recruitment procedures, or analysis population. It also does not report the trial’s original sample-size justification or the original assumptions used to plan enrollment. Those omissions limit assessment of how closely the posted analysis follows the intended design.

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

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 Patient Satisfaction, measured over Immediately following imaging modality (less than 30 minutes).

The primary endpoint was patient satisfaction immediately following the assigned imaging modality, with assessment within less than 30 minutes. The measure was a survey using a Likert scale from 1 to 5: 1 corresponded to very unsatisfied and 5 to very satisfied. The registry reports the outcome as a mean and standard deviation for each arm. A mean provides a group-level description of the recorded scores; it does not show how every participant responded or whether participants differed in their preferences.

Satisfaction is relevant to the study’s question because the investigators were comparing two approaches that differ in how the uterine cavity is assessed. Patient experience may be important alongside diagnostic and procedural outcomes. In this trial, however, satisfaction is the primary endpoint, not a direct measure of diagnostic accuracy, treatment success, or time to infertility treatment. Those are separate questions, some of which appear among the listed secondary outcomes.

The posted mean was 4.92 for office hysteroscopy and 4.84 for SIS. The registry records standard deviations of 0.34 and 4.7, respectively. The SIS spread is unusually large relative to the stated scale, and the registry record does not explain it. Interpretation of the mean comparison therefore needs to account for uncertainty about the reported SIS variability as well as the interval around the recalculated difference.

7. Results Posted in the Registry

• Saline Infusion Sonography (SIS): mean 4.84 versus 4.92 on control; difference -0.08 (95% CI -1.39 to 1.23), standardized effect d = -0.02; z-test p = 0.904.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Time to Complete

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Saline Infusion Sonography (SIS): mean 3.98 versus 4.61 on control; difference -0.63 (95% CI -1.51 to 0.25), standardized effect d = -0.28; z-test p = 0.158.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Saline Infusion Sonography (SIS) and the control. The interval gives the range of effects that remain compatible with the data.

Number of Patients Requiring Secondary Procedure

• Endpoint type: Binary: the number of participants with the event, compared as proportions.
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Saline Infusion Sonography (SIS): 22.0% (11/50) versus 2.0% (1/50) on control; risk difference 20.0 percentage points (95% CI 7.9 to 32.1), risk ratio 11.00 (1.48–82.03); unadjusted two-proportion z-test p = 0.002.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the proportion with the event is statistically higher for Saline Infusion Sonography (SIS) than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The secondary outcomes extend the study beyond immediate satisfaction to procedure duration, need for another procedure, time to infertility treatment, SIS predictive value, and office hysteroscopy’s ability to manage pathology. The available posted results include procedure time and participants requiring a secondary procedure. Results for time to infertility treatment, positive predictive value of SIS, and ability to manage pathology with office hysteroscopy are not reported in the registry record summarized by these results. The registry lists five secondary outcomes, but the available results do not permit a complete assessment of all of them.

Across the available secondary findings, the pattern is not simply a repetition of the primary satisfaction comparison. The outcomes address different constructs and have different data types, so their estimates should not be combined into a single claim about overall benefit. In particular, a result about procedural duration or a later procedure does not establish a difference in patient satisfaction, and the satisfaction result does not answer whether the approaches differ on those secondary questions.

Secondary findings generally carry less weight than a prespecified primary result when they are numerous or exploratory. Repeated testing creates more opportunities for apparently noteworthy results by chance. The registry record does not report a multiplicity adjustment or a hierarchy describing how the secondary questions were prioritized. The unadjusted secondary p-values therefore warrant cautious interpretation and should be treated as supporting or hypothesis-generating evidence rather than definitive confirmation.

The secondary outcomes also have distinct timeframes and measurement approaches. The procedure-time outcome covers the allotted procedure only; the secondary-procedure outcome is followed through study completion, up to 1 year. Those timeframes should not be conflated. The registry record does not report enough information about missing observations or analysis populations to determine whether all randomized participants contributed to every secondary endpoint.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Time to Complete
• Number of Patients Requiring Secondary Procedure
• Time to Infertility Treatment
• Positive Predictive Value of SIS
• Ability to Manage Pathology With Office Hysteroscopy

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is continuous in the registry’s statistical classification and is reported as a mean with a standard deviation. A mean summarizes the central level of the recorded satisfaction scores in an arm. A standard deviation describes variability among scores around that mean. Neither statistic describes the full distribution: different response patterns can produce similar means, and a mean does not reveal how many people selected each scale response.

What does the mean difference represent?

The recalculated comparison uses SIS minus office hysteroscopy. The estimate of -0.08 therefore points toward a lower average score in the SIS arm in the posted data, but its small size and uncertainty are important. The confidence interval runs from -1.386 to 1.226. Values below zero correspond to lower average satisfaction in SIS than in office hysteroscopy under this subtraction order; values above zero correspond to higher average satisfaction in SIS. The interval includes zero, which represents no mean difference under this comparison.

A confidence interval expresses the uncertainty associated with an estimate under the assumptions of the method used. It is not a range containing every participant’s score, nor does it show that every value inside it is equally likely. A narrow interval would indicate greater precision for the estimated group difference; a broad interval leaves more uncertainty about its magnitude and direction. In this result, the interval is broad enough that the posted data do not isolate a precise difference.

How should the p-values be read?

The recalculated unadjusted p-value is 0.904. A p-value measures how unusual data at least as incompatible with a specified null hypothesis would be under the statistical model, if that null hypothesis and model assumptions were true. It is not the probability that the null hypothesis is true, and it does not measure the size or practical importance of a difference. A large p-value is not proof of equivalence or absence of an effect.

The registry separately lists a Fisher Exact analysis with p = 0.57 for the primary outcome. The method label and p-value are reported, but the record does not describe the input or scoring procedure for this analysis, and it gives no effect estimate or confidence interval for it. The mean-based recalculation and the registry-listed analysis should be kept distinct because they are not presented as the same method. The record does not indicate a discrepancy flag.

Why does variability matter?

Greater variability makes it harder to estimate a group mean precisely when the number of observations is unchanged. It can also affect whether a model’s assumptions are reasonable. For a bounded scale, a reported spread that appears unusually large relative to the possible responses warrants careful checking. Here, the SIS standard deviation is recorded as 4.7 while the satisfaction scale ranges from 1 to 5. The record does not explain this value. As a result, the recalculated mean comparison should be understood as based on the posted summaries, not as a validation of the underlying score data.

Over-dispersion, in general, means that observed variability exceeds what a chosen statistical model expects. When that occurs, standard errors can be too small if the model does not account for the extra variation, making intervals too narrow and tests too favorable. This is a general statistical concern, not a finding that the trial’s analysis used an over-dispersed model. The record does not provide enough detail to diagnose the source of the SIS spread or establish whether it affected the registry-listed analysis.

What does randomization contribute?

Random assignment is intended to make treatment groups comparable, on average, with respect to measured and unmeasured factors at the time of assignment. A parallel design means the trial compares groups assigned to different approaches rather than describing a within-person crossover comparison. These design labels support interpreting the results as a randomized group comparison, but they do not guarantee that the groups were identical or that missing outcomes and post-assignment events cannot introduce bias.

The registry records no masking. It does not report the sequence-generation method, concealment procedures, adherence details, participant flow, or whether the analysis followed an intention-to-treat principle. Those details matter because they help assess whether allocation was implemented as planned and which participants contributed to each outcome. They are not recoverable from the means and p-values alone.

Why are recalculations described as unadjusted?

The recalculated comparison uses the posted arm-level summaries and does not incorporate covariate adjustment or other modeling beyond the simple comparison indicated by the reported outcome. An adjusted analysis could give a different estimate if it accounts for prognostic characteristics or other design features, but the registry record does not report such an analysis for this comparison. The recalculation is therefore a supplementary reading of the summary statistics, not a replacement for any fully documented trial analysis.

Likewise, the planning illustrations are not a measure of the trial’s observed power. They show hypothetical participant requirements under specified assumptions and selected fractions of the observed effect. The original design assumptions are not reported in the registry record. Statistical power is a prospective design concept, not a retrospective probability that the trial detected an effect.

11. Confidence Intervals and Precision

The primary mean difference is -0.08 units for SIS relative to office hysteroscopy. The recalculated confidence interval, from -1.386 to 1.226, is the main guide to the precision of that estimate. It spans zero and includes values in both directions. The posted summary therefore does not identify a precise direction or magnitude of difference in satisfaction between the groups.

The point estimate is close to zero, but a small point estimate alone is not enough to establish that the groups are similar. Precision depends on the interval as well as the estimate. A broad interval can include both a negligible difference and more substantial differences, so the result should not be interpreted as a demonstration of equivalence. The registry does not report a prespecified equivalence or non-inferiority margin.

The reported standard deviations also affect how confidently the group means can be interpreted. The registry records 0.34 for office hysteroscopy and 4.7 for SIS. The SIS value is unusually large relative to the satisfaction scale from 1 to 5, and the registry record does not explain it. This limits confidence in interpreting the variability and cautions against treating the recalculated interval as a complete account of data quality.

A confidence interval is conditional on the calculation and its assumptions. It does not account automatically for possible missing responses, measurement problems, selective reporting, or multiplicity. The registry record does not report enough information to determine whether these concerns affected the primary analysis. The interval is consequently useful for describing uncertainty in the posted comparison, but it cannot resolve uncertainties that are not represented in the calculation.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The planning figures are participants per arm for 80% power and participants per arm for 90% power. The outcomes represented in these calculations are not time-to-event outcomes, so the relevant quantity is participants per arm, not a total number of events. The illustrations use a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. They use the observed effect as a starting point and also consider smaller fractions of that observed effect.

The 80% power column describes a hypothetical design intended to have an 80% chance of detecting the specified effect under the stated assumptions, if that effect and the model assumptions were true. The 90% power column uses a higher target chance of detecting the specified effect under the same general framework. These are planning concepts, not guarantees: actual study results can differ because outcomes vary and assumptions may not hold.

Smaller effects are harder to distinguish from random variation, so planning for a smaller effect requires more participants per arm to reach the same target power, all else equal. The displayed illustrations make that relationship explicit by considering planning for 100%, 75%, and 50% of the observed effect. The values are based on the observed results, not the trial’s own design justification. The original sample-size assumptions are not reported in the registry record.

This is not observed power. It is a planning illustration calculated from the observed effect and stated assumptions; it does not measure the probability that this completed trial detected an effect. The enrollment and outcome results should be interpreted from the estimates and their uncertainty, rather than by treating a retrospective power calculation as evidence for or against a finding.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = -0.080; pooled standard deviation σ = 3.332.
2. n = 2 × (1.96 + 0.842)² × 3.332² / -0.080² = 27,232.7, rounded up to 27,233 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- -0.0800000000000001                      # observed difference in means
sigma <- 3.33208643345277                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(4415489)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 27,233 (80% power), 36,457 (90% power)
 75% of observed effect: n per arm = 48,414 (80% power), 64,813 (90% power)
 50% of observed effect: n per arm = 108,931 (80% power), 145,828 (90% power)
power.t.test: 27233.6 
Simulated power at n = 27,233 per arm: 0.796 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Analyses Reported by the Sponsor

The registry lists a Fisher Exact analysis for the primary satisfaction comparison, with p = 0.57. It does not report an effect estimate, confidence interval, or additional details about how that method was applied to the satisfaction scores. The posted means and standard deviations support a separate simple, unadjusted recalculation of the mean difference. That recalculation gives a difference of -0.08, a confidence interval from -1.386 to 1.226, and p = 0.904.

These results are not identical because the listed analysis and the recalculation are not described as the same statistical procedure. The record does not explain the input used for the Fisher Exact test, so it is not possible to reconcile the two results further from the registry information. The record does not flag a discrepancy. The recalculation should be read as a supplementary analysis of the posted summary statistics, while the registry-listed result remains the trial’s reported analysis; neither should be silently substituted for the other.

The same distinction applies to the secondary outcomes: the registry lists its own tests, while the recalculated comparisons are simple unadjusted contrasts. The record does not provide fuller model specifications or adjusted analyses. Readers should use the registry’s reported analysis as the study’s stated result and use the recalculation to understand the posted group summaries and their estimated uncertainty, with particular caution about the SIS standard deviation.

15. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary satisfaction outcome along with multiple secondary outcomes and analyses. When many outcomes are tested, the chance of obtaining one or more small p-values by chance can increase. Statistical procedures can account for this multiplicity, or a protocol can specify a hierarchy of outcomes, but neither an adjustment nor a testing hierarchy is reported in the registry record. The available secondary p-values should therefore be interpreted as unadjusted results unless the record says otherwise.

The registry does not report how missing satisfaction scores or missing secondary outcome data were handled. It does not provide the number of missing observations for each outcome, reasons for missingness, or a comparison of participants with and without observed results. Missingness can affect interpretation if the availability of an outcome is related to the assigned procedure or to the outcome itself. Without those details, the potential impact cannot be assessed from the posted summaries.

The analysis population is also not described. The record does not say whether the primary comparison included all randomized participants, only participants who completed the assigned procedure, or another defined group. It does not report adherence, crossovers, exclusions after randomization, or whether the analysis followed an intention-to-treat approach. These details are important for understanding whether the comparison preserves the benefits of random assignment.

The record identifies the study as randomized and unmasked, but it does not report allocation concealment or enough operational information to assess implementation. Nor does it give a protocol-level statistical analysis plan, details of interim analyses, or the original sample-size justification. These items are not reported in the registry record and should not be inferred from the completed status or the posted p-values. Their absence limits independent evaluation of prespecification, selective reporting, and the handling of data quality concerns.

These are reporting limitations, not proof that the study failed to address the issues in its conduct. They mean that readers cannot verify the relevant procedures from the registry record alone. The results remain interpretable as posted group summaries, but their evidential strength depends in part on methodological details that are unavailable.

16. Safety Results

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

Deaths

Other (non-serious) adverse events

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

The registry reports zero serious adverse events affected and zero other adverse events affected in the office hysteroscopy group. It reports the same figures in the SIS group. Deaths are recorded as zero in both groups, and no top serious adverse event terms are listed.

These entries describe the adverse-event figures recorded in the registry; they should not be read as proof that no discomfort, minor symptoms, or unrecorded events occurred. The registry record does not report detailed adverse-event definitions, collection procedures, severity categories beyond the listed serious and other classifications, or the completeness of safety follow-up. The safety entries also do not replace the patient satisfaction outcome, which measures a different aspect of the experience.

Because the registry does not provide further event descriptions or methods, the figures support only a limited statement about what was posted: no affected participants are recorded in the listed serious or other adverse-event fields for either group, and deaths are recorded as zero. The available record does not support broader conclusions about comparative safety.

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

The posted primary data describe similar group means on the satisfaction scale, with an unadjusted recalculated difference close to zero. However, the confidence interval is broad and includes differences in either direction. The data therefore do not establish a clear difference in mean satisfaction, but they also do not demonstrate that the two approaches are equivalent. The unusually large SIS standard deviation recorded relative to the 1-to-5 scale is an additional reason to interpret the summary cautiously.

The result applies to patient-reported satisfaction measured immediately after the imaging modality, within less than 30 minutes. It does not determine whether the procedures differ in diagnostic performance, management of uterine pathology, time to infertility treatment, or other outcomes. Those questions require their own complete results and appropriate interpretation. Some of the listed secondary outcomes do not have results reported in the registry record.

The randomized design supports a comparative question, but important details about implementation, missing data, and analysis populations are not reported in the registry record. The reported analyses also include a registry-listed Fisher Exact result and a separate mean-based recalculation, without enough explanation to reconcile their methods. These limitations do not erase the posted results; they define what can be concluded from them.

In statistical terms, a non-small p-value is not evidence that the null hypothesis is true, and a confidence interval crossing zero is not proof of no effect. The appropriate conclusion is narrower: the posted satisfaction summaries do not precisely establish a difference between the assigned approaches. No medical recommendation follows from this statistical comparison alone. Clinical choices require consideration of the broader evidence, context, and individual circumstances, none of which are fully evaluated by this endpoint.

18. Why This Trial Matters Statistically

This trial is statistically relevant because it compares two approaches that the investigators described as serving a similar evaluation purpose but differing in how assessment is performed. A randomized parallel design makes a direct group comparison possible, and the primary endpoint captures patient-reported experience rather than relying only on procedural or diagnostic measures. Including several distinct secondary outcomes also reflects that satisfaction, procedure duration, later procedures, treatment timing, and pathology management are separate dimensions of the question.

The results illustrate why a point estimate and a p-value are not enough. The mean difference is close to zero, but the interval is broad and includes both directions. That combination supports a cautious interpretation rather than a claim of equivalence. The SIS standard deviation recorded on the satisfaction scale further illustrates how an unusual summary value can affect confidence in an otherwise straightforward comparison.

The record also demonstrates the importance of clear statistical reporting. A registry-listed Fisher Exact p-value accompanies a continuous satisfaction outcome reported by means and standard deviations, while a simple recalculation gives a different p-value. Without additional method details, readers cannot fully reconcile those analyses. Reporting the estimand, analysis population, treatment of missing data, multiplicity approach, and interval for the primary reported analysis would make the evidence easier to evaluate.

Finally, the study’s rationale raises questions about procedure tolerability, resource use, and the possibility of managing pathology during diagnosis. The posted primary satisfaction result addresses only one part of that rationale. A complete statistical assessment also depends on results for the other outcomes and transparent methods, which are not fully reported in the registry record.

19. 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.

A central limitation is the SIS standard deviation of 4.7 recorded for a satisfaction scale ranging from 1 to 5. This value is unusually large in relation to the scale, and the registry record does not explain it. The concern affects interpretation of variability and the mean-based recalculation. It should be recognized without assuming whether the cause is a transcription issue, an unusual scoring convention, or the underlying data.

The registry reports a Fisher Exact test for the primary outcome but does not describe how that test was applied to satisfaction scores. It provides no effect estimate or interval for that analysis. The unadjusted recalculation from the arm summaries is therefore informative but cannot resolve the missing methodological detail or substitute for a fully documented primary analysis.

The record does not report participant characteristics, detailed eligibility criteria, allocation concealment, participant flow, missing outcome counts, analysis populations, adherence, crossovers, or reasons for exclusions. It also does not report the original sample-size justification, interim analyses, or a statistical analysis plan. These omissions limit assessment of trial conduct, precision planning, and the possibility of selection or reporting bias.

Results for some listed secondary outcomes are not reported in the registry record summarized by these results. Without complete outcome reporting and a stated approach to multiplicity, secondary findings require restraint. The registry also records no masking, which may matter for a subjective satisfaction outcome; the record does not provide further details about who administered or scored the survey.

These limitations do not determine the direction of any treatment effect. They qualify how confidently the posted estimates can be interpreted and identify questions that cannot be answered from the registry information alone.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: SIS Versus Office Hysteroscopy for Uterine Cavity Evaluation Prior to IVF — NCT04415489.
• Registry record last updated 2021-05-19; status last verified 2021-03.
• Results first posted 2021-04-14.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

23. Record Summary

NCT04415489 is a completed randomized parallel-group trial sponsored by the University of North Carolina, Chapel Hill. It compared office hysteroscopy with SIS for uterine cavity evaluation before IVF among participants with infertility. The registry lists enrollment of 100 and no masking.

The primary endpoint was patient satisfaction immediately after the procedure, measured on a Likert scale from 1 to 5. The posted group means were 4.92 for office hysteroscopy and 4.84 for SIS. The unadjusted recalculated difference was -0.08, with a confidence interval from -1.386 to 1.226 and p = 0.904. The registry separately reports a Fisher Exact analysis with p = 0.57; details reconciling that analysis with the continuous outcome are not reported.

The registry lists secondary outcomes and reports selected results, but results for some listed outcomes are not reported in the registry record. The SIS standard deviation of 4.7 is unusually large relative to the stated scale and is unexplained. Missing-data methods, analysis populations, multiplicity handling, and the original sample-size justification are not reported in the registry record.