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 Early Anatomy Scan for Evaluation of Obese Pregnant Women (EASE-O) (NCT04639973), a randomized na study. The primary outcome is Completion Rate for First Trimester Scans.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04639973 |
| Phase | NA |
| Condition | Obesity |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 128 |
| Arms in the primary outcome | n/a |
| Lead sponsor | The University of Texas Health Science Center, Houston |
| Results posted | Yes |
2. Clinical Question
Population
The trial concerns obese pregnant women. The registry record does not report further eligibility details or describe the participants’ characteristics, such as age or other clinical features.
Intervention
Group 1 was assigned to a first trimester ultrasound. The stated aim included assessing whether ultrasound in the first trimester is feasible and whether fetal anatomy views can be completed at that time.
Comparator
Group 2 was assigned to a second trimester anatomy ultrasound. The registry summary also describes interest in a first trimester and second trimester scan combination, but arm descriptions do not provide further procedural details.
Primary question
The primary outcome is the completion rate for first trimester scans at 12-14 weeks of pregnancy. Completion is defined as the number of scans that see all the views divided by the total number of scans in that group. The trial’s broader stated purpose was to assess feasibility and compare completion rates across the scan timing approaches. The registry record does not report the completion result or an estimated difference between groups.
3. Trial Design
EASE-O is described as a randomized, single-masked, parallel trial. It enrolled 128 participants and is listed as completed. The recorded start date is 2021-02-01, and the primary completion date is 2022-04-30. The sponsor is The University of Texas Health Science Center, Houston. The phase is listed as NA.
The two registered groups were Group 1 (First trimester ultrasound) and Group 2 (Second trimester anatomy ultrasound). Both interventions are classified as diagnostic tests. The registry record does not describe how randomization was generated or concealed, who was masked, or whether masking was maintained throughout the study. It also does not provide detailed arm procedures or explain the allocation process.
The primary outcome is the completion rate for first trimester scans, with a timeframe of 12-14 weeks of pregnancy. Registered secondary outcomes include completion rates for first and second trimester scans, scan time in the first trimester group, anomalies identified or missed in each group, infant survival, and gestational age at delivery. There are 15 outcome measures listed, but the registry record does not report numerical outcome results. It also does not report statistical analysis results.
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 | Group 1 (First Trimester Ultrasound) | Group 2 (Second Trimester Anatomy Ultrasound) |
|---|---|---|
| STARTED | 65 | 63 |
| COMPLETED | 62 | 62 |
| NOT COMPLETED | 3 | 1 |
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: Data were not collected from one participant in the group 1 (first trimester ultrasound) arm.
| Characteristic | Unit | Group 1 (First Trimester Ultrasound) | Group 2 (Second Trimester Anatomy Ultrasound) | Total |
|---|---|---|---|---|
| Participants analysed | 64 | 63 | 127 | |
| Age, Continuous | years | 30.3 (26.3 to 36.6) | 30.9 (27.2 to 34.4) | 30.8 (26.5 to 35.6) |
| Sex: Female, Male: Female | Participants | 64 | 63 | 127 |
| Sex: Female, Male: Male | Participants | 0 | 0 | 0 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 25 | 26 | 51 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 35 | 35 | 70 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 4 | 2 | 6 |
| Race/Ethnicity, Customized: White | Participants | 21 | 30 | 51 |
| Race/Ethnicity, Customized: Black | Participants | 30 | 27 | 57 |
| Race/Ethnicity, Customized: Asian | Participants | 1 | 0 | 1 |
| Race/Ethnicity, Customized: Native Hawaiian or Pacific Islander | Participants | 10 | 6 | 16 |
| Race/Ethnicity, Customized: Other | Participants | 2 | 0 | 2 |
| Region of Enrollment: United States | participants | 64 | 63 | 127 |
| Insurance: private | Participants | 26 | 21 | 47 |
| Insurance: government assisted | Participants | 37 | 40 | 77 |
| Insurance: self pay | Participants | 1 | 1 | 2 |
| Insurance: no insurance | Participants | 0 | 1 | 1 |
| Marital Status: Single | Participants | 29 | 24 | 53 |
| Marital Status: Separated | Participants | 1 | 1 | 2 |
| Marital Status: Married | Participants | 32 | 34 | 66 |
| Marital Status: Not Reported | Participants | 2 | 4 | 6 |
| Education: less than highschool | Participants | 4 | 1 | 5 |
| Education: Highschool/GED | Participants | 14 | 16 | 30 |
| Education: some college | Participants | 19 | 17 | 36 |
| Education: college graduate | Participants | 12 | 14 | 26 |
| Education: post graduate | Participants | 2 | 5 | 7 |
| Education: unknown | Participants | 13 | 10 | 23 |
| Pre-pregnancy Body Mass Index | kg/m^2 | 40 (37 to 48) | 40 (38 to 47) | 40 (37.2 to 46.9) |
| Number of participants with Chronic Hypertension | Participants | 18 | 11 | 29 |
| Gestational age at enrollment | weeks | 10.14 (8.57 to 12.14) | 11.00 (8.57 to 12.43) | 10.7 (8.57 to 12.2) |
| Gestational age at anatomy scan | weeks | 13.3 (13 to 13.7) | 20.4 (20.1 to 21.4) | 18.8 (13.3 to 20.4) |
| Number of Participants with Type 2 Diabetes Mellitus | Participants | 14 | 4 | 18 |
| Parity | completed pregnancies | 1 (0 to 2) | 1 (.5 to 2) | 1 (0 to 2) |
6. Primary Endpoint
The registry lists the primary outcome as Completion Rate for First Trimester Scans, measured over 12-14 weeks of pregnancy.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percent |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the completion rate for first trimester scans at 12-14 weeks of pregnancy. The registry defines a completed scan as one that sees all the views; the rate is the number of scans meeting that definition divided by the total number of scans in that group. The registry record does not report the observed numerator, denominator, or completion rate.
Completion is a feasibility measure: it indicates whether the scan was able to obtain the required views under the study conditions. In general, such an endpoint can help distinguish whether an assessment was technically completed from whether an abnormality was detected. It does not, by itself, establish the accuracy of a scan or describe clinical consequences.
The trial’s stated purpose includes assessing completion at different pregnancy stages. However, the registered primary outcome is specifically the completion rate for first trimester scans, while the broader description refers to comparison with second trimester completion and the combination of scans. The registry record does not report how the primary endpoint was analyzed, whether the comparison was prespecified as a primary contrast, or the corresponding estimate and uncertainty.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes the design question but does not provide the primary completion result. Without a reported count of completed scans, total scans, or an estimated completion rate, the observed feasibility of the first trimester approach cannot be quantified from the record. Nor can the size or precision of a difference between scan timing groups be assessed.
For a completion-rate outcome, the estimate would ordinarily be interpreted as the proportion of scans meeting the all-views criterion in the relevant group. A comparison would need to specify which groups and scan opportunities form the contrast. The trial description refers to first trimester scans, second trimester scans, and a combination of scans, but the registry record does not report a numerical result for any of these completion outcomes. The primary outcome’s stated definition alone is not evidence that completion was high or low.
In general, a confidence interval describes the range of values reasonably compatible with the observed data under the analysis assumptions. It helps convey precision as well as the direction and size of an estimate. No confidence interval for the primary outcome is reported in the registry record. A p-value, adjusted or unadjusted effect estimate, or model-based analysis result is also not reported. The record lists zero analyses.
The trial registered secondary outcomes concerning scan duration, anomalies identified or missed, infant survival, and gestational age at delivery. Their inclusion indicates the outcomes of interest, not what the study found. The registry record does not report their results, definitions beyond the listed titles, or statistical comparisons. In particular, no conclusions about anomaly detection or delivery outcomes can be drawn from their registration alone.
Because numerical primary results and uncertainty measures are unavailable, the posted record does not support judging how strongly the observed data favor one scan timing approach over another. This is a limitation of the available result reporting, not evidence that the approaches had similar outcomes or that no difference was present.
9. Statistical Methods Explained
The registry identifies a randomized, parallel design, but it does not report the statistical methods used to analyze the outcomes. The following concepts are general explanations of how such outcomes can be analyzed; they are not claims about methods used in EASE-O.
How can a completion rate be analyzed?
In general, a completion rate is a proportion: scans meeting the stated completion criterion form the numerator, and the eligible scans form the denominator. The registry defines completion as seeing all the views. A clear analysis should specify whether the unit is a participant, a scan, or a scan opportunity, and how repeated scans from the same participant are handled. Those details are not reported in the registry record.
A proportion can be reported for each group, with an uncertainty interval reflecting the amount of information in the observed data. A group contrast can be expressed in different ways, such as a difference in proportions or a relative measure. Each expression answers a somewhat different question, and an interpretation depends on its definition and interval. The registry record does not report an estimate, interval, or method for the primary outcome.
Why does the comparison need a clear definition?
The summary describes several questions: feasibility of first trimester ultrasound, completion in the first trimester compared with the second trimester, and completion for a combination of scans compared with individual evaluations. The primary outcome title specifies completion for first trimester scans. These descriptions do not identify a reported numerical contrast. General statistical practice is to define the target comparison and outcome population before interpreting an estimate. The registry record does not report an analysis specification that resolves how the broader questions relate to the primary endpoint.
What does randomization contribute?
In general, random assignment aims to make groups comparable at the start of a study, on average, so that outcome contrasts can be interpreted in light of assigned strategy. Randomization does not ensure that every group characteristic is identical, and it does not remove the need to report participant flow, outcome availability, and the analysis population. The registry confirms randomized allocation but does not report the sequence-generation or concealment methods, baseline characteristics, participant flow, or analysis population.
How should uncertainty be read?
In general, a confidence interval communicates the precision of an estimate. A narrow interval indicates greater statistical precision than a wide interval, given the model and data; it does not establish that an outcome is clinically important. A p-value addresses compatibility between data and a specified statistical model under a null hypothesis, but it does not measure effect size or the probability that a hypothesis is true. Neither a confidence interval nor a p-value for the primary outcome is reported in the registry record.
What do the registered secondary outcomes add?
The listed secondary outcomes include scan completion, time to complete the first trimester scan, anomaly counts, infant survival, and gestational age at delivery. In general, multiple outcomes can lead to multiple statistical comparisons. If many comparisons are made, chance findings become more likely unless the analysis plan addresses multiplicity or the results are interpreted as exploratory. The registry record does not report an analysis plan, multiplicity procedure, or outcome-specific results. It is therefore not possible to establish which comparisons were conducted or how they were interpreted.
What is the role of sample-size planning?
In general, a sample-size calculation describes the number of participants needed under stated assumptions about the effect to detect, variability, significance level, power, and allocation. It is a planning exercise, not a measure of what the completed study observed. Any sample-size illustration based on an observed effect is not the trial’s original design justification and is not observed power. The registry record does not report the trial’s own sample-size justification, design assumptions, or analysis plan. Without reported outcome estimates, no study-specific interpretation of precision or detectable effects can be made.
10. Multiplicity, Missing Data and Analysis Populations
The registered outcomes cover more than the primary completion endpoint. The secondary outcomes include completion at both pregnancy stages, scan time, anomalies identified or missed, infant survival, and gestational age at delivery. When multiple outcomes or contrasts are analyzed, general statistical practice is to state which analyses are primary and how the possibility of chance findings across comparisons will be handled. The registry record does not report a multiplicity plan or identify which secondary analyses, if any, were performed.
Missing outcome data can affect a completion rate if scans or participants lack an evaluable result. A transparent analysis would ordinarily report how many observations were available, why data were missing, and how the analysis treated them. The registry record does not report missing-data counts, reasons, or methods.
The analysis population is also not reported. The record does not say whether the primary analysis followed randomized assignment, included only participants who received their assigned scan, or used another population definition. No participant flow or outcome-specific denominators are reported. These omissions prevent assessment of whether the analyzed groups corresponded to the randomized groups and how incomplete observations may have affected the results.
The registry lists zero analyses, so no analysis results or analysis population definitions are available for interpretation. It is not possible to infer that analyses were not conducted; only that they are not reported in the registry record.
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 |
|---|---|---|---|
| Group 1 (First Trimester Ultrasound) | 5 | 64 | 7.8% |
| Group 2 (Second Trimester Anatomy Ultrasound) | 1 | 63 | 1.6% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Group 1 (First Trimester Ultrasound) | 0 of 64 |
| Group 2 (Second Trimester Anatomy Ultrasound) | 0 of 63 |
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 |
|---|---|
| Group 1 (First Trimester Ultrasound) | 0 of 64 |
| Group 2 (Second Trimester Anatomy Ultrasound) | 0 of 63 |
Most frequent serious adverse event terms
| Event term | Organ system | Group 1 (First Trimester Ultrasound) | Group 2 (Second Trimester Anatomy Ultrasound) |
|---|---|---|---|
| Miscarriage | Pregnancy, puerperium and perinatal conditions | 3 of 64 | 0 of 63 |
| Fetal death | Pregnancy, puerperium and perinatal conditions | 1 of 64 | 1 of 63 |
| Neonatal death | Pregnancy, puerperium and perinatal conditions | 1 of 64 | 0 of 63 |
Serious events with the highest arm-level rate: miscarriage (4.7%), fetal death (1.6%), neonatal death (1.6%).
The registry lists serious adverse event counts for each group. For Group 1 (First Trimester Ultrasound), the serious adverse event fields list 5 affected among 64 at risk. For Group 2 (Second Trimester Anatomy Ultrasound), they list 1 affected among 63 at risk. The listed death counts are 0 in each group. The other adverse event fields list 0 affected among 64 at risk in Group 1 and 0 affected among 63 at risk in Group 2.
The serious-event terms listed are Miscarriage at 4.7%, Fetal death at 1.6%, and Neonatal death at 1.6%. The registry record does not report how these terms are distributed by group, whether events could overlap within participants, or the definitions and attribution rules used. The term list should therefore not be treated as a group-specific comparison or as a causal assessment of the ultrasound strategies.
Counts alone do not establish whether an event was caused by an intervention. General safety interpretation also depends on event definitions, timing, follow-up, and completeness of reporting. Those details are not reported in the registry record.
12. What the Result Does, and Does Not, Mean
The registry record describes a randomized study of first and second trimester ultrasound strategies in obese pregnant women, with a primary outcome focused on completion of first trimester scans. It also lists broader interests in scan feasibility, completion across pregnancy stages, and several secondary outcomes. These details clarify the questions the study was designed to address.
They do not show whether first trimester scans were completed, how completion compared between groups, how many anomalies were identified or missed, or what the delivery outcomes were. Those results are not reported in the registry record. The record also does not provide effect estimates, uncertainty intervals, p-values, or analysis methods. Accordingly, it is not possible to characterize the direction, size, or precision of any treatment-group contrast from the posted results.
In general, a randomized design can support a causal comparison when the assigned groups, outcome measurement, follow-up, and analysis are sufficiently reported and the analysis respects the design. Randomization alone does not supply the missing outcome results or establish that all relevant sources of bias were addressed. The record does not provide enough information to evaluate those features in detail.
The event counts and listed adverse-event terms are descriptive registry entries. They do not, on their own, establish a causal relationship between a scan strategy and an event. The record’s lack of a reported primary result should not be interpreted as evidence of equal outcomes, absence of an effect, or failure of either strategy. It means that the available registry information does not permit those conclusions.
13. Why This Trial Matters Statistically
This trial raises a statistical question about feasibility rather than only about whether an imaging assessment can identify an abnormality. The primary endpoint asks whether all required views were obtained during first trimester scans. This kind of completion measure can be informative about whether an assessment is technically achievable under the conditions studied, while remaining distinct from diagnostic accuracy or clinical benefit.
The timing comparison also makes clear why outcome definitions and denominators matter. Completion could be counted per scan, participant, or opportunity to scan; the registry defines the numerator and denominator in terms of scans, but does not give observed counts or further denominator details. A clear report of those elements is necessary for readers to interpret the rate and compare groups.
Randomization offers a framework for comparing assigned approaches, but a useful statistical interpretation requires outcome estimates and their precision, along with participant flow, missing-data handling, and a defined analysis population. The registry record confirms randomization and lists the outcomes, yet does not report those analysis details or results. This leaves the central statistical question unresolved in the record.
More generally, this study illustrates that registering outcomes and completing a trial are not substitutes for reporting results. Registered outcome definitions explain what was intended to be measured. Numerical results and analysis methods are needed to judge what the observed data say and how uncertain those findings are.
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 main limitation for interpreting EASE-O from the registry record is that the primary outcome result is not reported. There are no reported completion counts, rates, group contrasts, or uncertainty estimates. Secondary outcome results are also not reported, so the broader questions about scan duration, anomalies, infant survival, and gestational age at delivery cannot be assessed.
Several details needed to evaluate the design are absent. The record does not report the eligibility criteria beyond the focus on obese pregnant women, baseline characteristics, randomization procedures, allocation concealment, or who was masked. The group descriptions do not provide further scan procedures. The analysis population, missing-data methods, and statistical analysis plan are not reported.
The record lists serious and other adverse event counts, but does not provide event definitions, group-specific detail for the listed serious-event terms, or information about attribution and follow-up. These limits prevent a detailed interpretation of safety reporting or a causal comparison of events.
The record is marked completed, but completion status does not supply outcome evidence. It also lists 15 outcome measures and zero analyses; this does not establish whether analyses were conducted outside the registry, only that analysis results are not reported there. These limitations concern what can be interpreted from the registry record, rather than proof that the underlying study did not collect additional information.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Early Anatomy Scan for Evaluation of Obese Pregnant Women (EASE-O) — NCT04639973.
- Registry record last updated 2024-05-21; status last verified 2024-04.
- Results first posted 2023-07-13.
- 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
EASE-O is a completed, randomized, single-masked, parallel trial sponsored by The University of Texas Health Science Center, Houston. The registry lists enrollment of 128, a start date of 2021-02-01, and a primary completion date of 2022-04-30. The two groups were assigned to first trimester ultrasound or second trimester anatomy ultrasound.
The primary outcome is completion of first trimester scans at 12-14 weeks of pregnancy, defined by whether all views were seen. Secondary outcomes include scan completion, scan time, anomalies identified or missed, infant survival, and gestational age at delivery. Although the record lists 15 outcome measures, it reports no analysis results. The primary completion result, statistical methods, missing-data handling, and analysis population are not reported in the registry record.