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 Conditionally Increased Output (CIO) Enhanced Ultrasound System (NCT05792423), a na na study. The primary outcome is Mean Difference in Aspartate Transaminase (AST) Value in U/L Unit Between Pre-imaging and day7 Post-imaging.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05792423 |
| Phase | NA |
| Condition | Nonalcoholic Fatty Liver, Nonalcoholic Steatohepatitis, Fatty Liver |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 24 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Massachusetts General Hospital |
| Results posted | Yes |
2. Clinical Question
Population
The record lists 24 healthy adult volunteers. Its title and stated motivation concern ultrasound shear wave elastography in people with obese fatty liver disease, and the listed conditions include nonalcoholic fatty liver, nonalcoholic steatohepatitis, and fatty liver. The enrolled group is described as healthy volunteers, however, so the registry description does not establish that the participants had those conditions or were obese.
Intervention
Participants underwent imaging with a GE ultrasound system using increased acoustic output settings, described as conditionally increased output. The study aimed to monitor possible bioeffects after the ultrasound exposure using liver function tests. Its summary also describes a secondary aim of assessing whether shear wave elastography results improved with the increased-output approach.
Comparator
The record describes a single-group study, not a randomized comparison between separate groups. A listed secondary outcome compares the IQR-to-median ratio between standard and conditionally increased-output shear wave elastography. The record does not report the allocation method, sample size, or analysis details for that within-study comparison, and the healthy-volunteer group should not be interpreted as a separate control arm.
Primary question
The primary outcome is the mean difference in AST between the pre-imaging measurement and the measurement 7 days after imaging. It was intended to monitor a possible liver-injury effect associated with the increased-output imaging method. The registry record identifies a 95% confidence interval as the dispersion measure but does not report the estimated difference or its interval. Consequently, the recorded aim can be described, but the observed change and its precision cannot be evaluated from the registry record.
3. Trial Design
This is a completed, single-group device study sponsored by Massachusetts General Hospital. The registry lists an enrollment of 24 and describes the group as 24 healthy adult volunteers. The intervention is a GE ultrasound system with increased acoustic output settings. The study was not assigned a phase, and allocation is recorded as NA. Masking is listed as none. These features describe an open, single-group setup; they do not establish a randomized treatment comparison.
The registry gives a start date of 2023-06-30 and a primary completion date of 2024-05-31. The overall status is completed. Completion status indicates that the study record is marked completed, but it does not by itself provide the results of the planned measurements. The primary outcome is a pre-imaging to day-7 AST mean difference, with the timeframe described as within a 2-week period after ultrasound imaging.
The study summary says liver function tests were to be collected before imaging and up to 7 days afterward, with results graded according to the NCI scale for drug hepatotoxicity. It also describes a secondary aim of assessing shear wave elastography performance with conditionally increased output. Listed secondary outcomes include the IQR-to-median ratio comparison between standard and increased-output imaging, as well as pre-imaging to day-1 and day-2 differences for AST, ALT, and ALP.
The title and rationale refer to obese fatty liver disease, while the study group is identified as healthy adult volunteers. The registry record does not explain this difference or give additional eligibility details. It also does not report a separate control group, the imaging sequence, or the full analysis plan. The design can therefore be characterized from the stated group and intervention, but the extent to which the performance comparison was paired or otherwise structured is not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Evaluation of Liver Stiffness Using Conditionally Increased Output (CIO) Enhanced Ultrasound System |
|---|---|
| STARTED | 24 |
| COMPLETED | 22 |
| NOT COMPLETED | 2 |
Reasons for not completing this period:
| Reason | Evaluation of Liver Stiffness Using Conditionally Increased Output (CIO) Enhanced Ultrasound System |
|---|---|
| Withdrawal by Subject | 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.
Population: Healthy adult volunteers who underwent CIO and were included in the analysis.
| Characteristic | Unit | Evaluation of Liver Stiffness Using Conditionally Increased Output (CIO) Enhanced Ultrasound System |
|---|---|---|
| Participants analysed | 22 | |
| Age, Continuous | years | 39.6 (SD 16.3) |
| Sex: Female, Male: Female | Participants | 15 |
| Sex: Female, Male: Male | Participants | 7 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 2 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 20 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 3 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 2 |
| Race (NIH/OMB): White | Participants | 13 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 4 |
| Region of Enrollment: United States | participants | 22 |
6. Primary Endpoint
The registry lists the primary outcome as Mean Difference in Aspartate Transaminase (AST) Value in U/L Unit Between Pre-imaging and day7 Post-imaging, measured over Pre-ultrasound imaging and 7 day after the ultrasound imaging (within 2 weeks timeframe).
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | international units per liter |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is the mean difference in aspartate transaminase (AST), measured in international units per liter, between before ultrasound imaging and 7 days after imaging. The stated timeframe allows measurement within a 2-week period. AST is one of the liver function tests named in the study summary, and the registry describes this endpoint as a way to monitor a possible liver-injury effect associated with conditionally increased-output liver stiffness imaging.
A mean difference expresses the average change between the specified measurement occasions for the participants included in the analysis. Its interpretation depends on the subtraction order and the analysis population; the registry record does not specify the direction convention or provide an estimate. The record names a 95% confidence interval as the dispersion measure. In general, a confidence interval conveys the uncertainty around an estimated effect under the assumptions of the analysis; it is not a guarantee that the true effect lies within the interval.
No primary endpoint estimate or confidence interval is reported in the registry record. The magnitude, direction, and precision of the AST change therefore cannot be described. The endpoint is a planned safety-monitoring measure, not by itself a complete characterization of all possible bioeffects or of the diagnostic performance of shear wave elastography.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record defines a safety question and a measurement schedule but does not report the primary AST mean difference or its 95% confidence interval. As a result, there is no posted estimate from which to describe the direction or magnitude of the pre-imaging to day-7 change, and no interval from which to assess its statistical precision. The study's completed status does not fill this results gap.
The absence of an outcome estimate should not be interpreted as evidence that AST did not change. It also does not establish that an increase or decrease occurred. Those conclusions require the actual participant measurements or a reported analysis, neither of which appears in the registry record. The same limitation applies to the listed secondary outcomes: the record names the IQR-to-median ratio and changes in AST, ALT, and ALP at earlier follow-up times, but does not give their numerical results.
The study is single-group. The primary AST endpoint compares measurements over time within the group, rather than comparing outcomes between independently assigned intervention and control groups. In general, within-person measurements can account for stable differences between participants when the analysis uses paired observations, but the registry does not report the analysis details needed to determine how those data were handled. Temporal changes in a single group also cannot, by themselves, separate an imaging-related effect from other changes over the follow-up period.
The stated rationale concerns performance of shear wave elastography in obese fatty liver disease patients, but the listed participants are healthy adult volunteers. This distinction matters for how broadly the findings could be interpreted even if numerical results were available. The record does not describe whether the group included people with fatty liver disease or obesity, nor does it explain the difference between the intended population in the title and the arm description.
The safety entries report no serious adverse events affecting the listed group, two other adverse events affecting participants, and no deaths. These counts describe recorded events, not the AST endpoint, and the record does not identify event types or their relationship to imaging. The small, single-group record and missing outcome estimates leave important uncertainty about both the safety measurements and the performance aim. No conclusion about the effect of increased output can be drawn from the registry outcomes as posted.
9. Statistical Methods Explained
Methods can be understood at two levels: what the registry says was measured, and what statistical procedures would generally mean. The record specifies a continuous primary endpoint summarized as a mean, with a 95% confidence interval. It does not report the estimate, interval limits, analysis population, or detailed statistical plan. General explanations below describe statistical concepts and should not be read as confirmation that a particular procedure was used in this study.
What does a mean difference represent?
For the primary endpoint, the target quantity is the average difference in AST between the pre-imaging measurement and the day-7 measurement. A mean summarizes the central value of a continuous measurement by averaging observations. A difference describes change between two occasions, but interpretation requires knowing which occasion was subtracted from which. That direction convention is not reported in the registry record. Without the estimate, it is not possible to say whether the reported mean change was positive, negative, or close to zero.
In general, an analysis of repeated measurements may use each participant's pair of measurements, or may model the measurements in another way. A paired analysis focuses on within-participant changes and can account for the fact that observations from the same person are related. A model-based analysis may handle repeated measurements through an explicit correlation structure. The registry identifies the before-imaging and follow-up occasions but does not report which approach was used, how incomplete pairs were treated, or whether the primary estimate was adjusted for any other variables.
How should a confidence interval be read?
A confidence interval communicates uncertainty around an estimate. In general, a narrower interval indicates greater precision under the assumptions of the method, while a wider interval indicates less precision. The interval is not a measure of the range of individual participants' changes, and it does not show how many participants experienced a particular change. The registry names a 95% confidence interval for the primary mean difference but does not report its limits. Its precision therefore cannot be judged.
Statistical significance and clinical or practical importance are distinct ideas. In general, a test result addresses compatibility with a specified statistical null hypothesis, while the estimated magnitude and its uncertainty help describe the range of effects consistent with the data. Neither a p-value nor a confidence interval is listed for the primary endpoint in the registry record. No inference about statistical significance or importance can be made from the outcome description alone.
What does the performance measure capture?
The listed performance outcome is the mean difference in the IQR-to-median ratio between standard and conditionally increased-output shear wave elastography. The interquartile range describes the spread of the middle portion of measurements; dividing it by the median expresses that spread relative to the central measurement. In general, a ratio of this kind can be used to describe measurement variability relative to the typical value. It does not by itself establish diagnostic accuracy or prove that one imaging setting is preferable. The record does not provide the ratio values, difference estimate, uncertainty interval, or direction convention.
The registry also lists changes in AST, ALT, and ALP between baseline and day 1 or day 2 as secondary outcomes. These are continuous laboratory measurements at specified time points. In general, repeated measurements can be summarized as changes from baseline, but conclusions depend on the method of calculating change, the data available at each time, and how the analysis handles repeated observations. Those details and the numerical results are not reported in the registry record.
What are the sample-size illustrations?
The stated assumptions for planning illustrations describe a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and effects set as fractions of an observed effect. They are described as illustrations based on an observed effect, not as the trial's own design or as observed power. That distinction is important: a planning illustration asks what sample size might be needed under stated assumptions, whereas observed power is not a substitute for reporting an effect estimate and its uncertainty.
The registry describes this study as single-group, while the planning assumptions refer to equal allocation between two arms. Those assumptions therefore should not be mistaken for a description of the enrolled design. The actual sample-size rationale, any formal justification, and the numerical planning results are not reported in the registry record. Without reported estimates and their uncertainty, the planning illustrations cannot be independently interpreted as evidence about the trial's observed effect.
Why can variability matter?
In general, variability affects the precision of a mean estimate. Greater variability among participant measurements tends to make a mean less precise when other aspects of the analysis are unchanged. For imaging measures, variability may also be an outcome of interest, which is consistent with the listed IQR-to-median ratio comparison. Over-dispersion is a general statistical concern when observed variability exceeds what a chosen model assumes; if present, standard errors and confidence intervals based on an unsuitable model may be misleading. The registry record does not report a dispersion assessment or a model check, so no claim about over-dispersion in this study is warranted.
Overall, the registry identifies the endpoint types, time points, and confidence-interval convention, but not the estimates or the statistical procedures used to produce them. The statistical concepts explain how such results are usually read; they cannot replace the missing analysis details or numerical results.
10. Multiplicity, Missing Data and Analysis Populations
The record lists a primary AST outcome and several secondary outcomes, including a shear wave elastography IQR-to-median ratio comparison and changes in AST, ALT, and ALP at day 1 and day 2. It does not report whether the analyses were organized into a prespecified testing hierarchy, whether multiplicity adjustments were planned, or how the interpretation of multiple comparisons was handled. These details are not reported in the registry record.
In general, evaluating multiple outcomes or time points can increase the chance of observing at least one apparently unusual result by chance if each is tested separately without an appropriate strategy. Multiplicity procedures can address that issue, while a prespecified distinction between primary and secondary outcomes can help clarify which result carries the main confirmatory role. The listed primary outcome is AST at day 7, but the record does not state how other results were intended to support or qualify it.
The registry does not report outcome-level missingness, participant flow by analysis, or the number of observations available at each time point. It also does not state whether missing values were imputed, excluded, or handled using a model. The number enrolled is recorded as 24, but this does not establish how many participants contributed to each endpoint analysis.
The analysis population is not described beyond the group of healthy adult volunteers. The registry record does not report whether all enrolled participants were included, whether exclusions occurred, or whether any sensitivity analyses were planned. Without these details, the potential effect of missing measurements and analysis-population choices cannot be assessed. No statistical plan or interim-analysis approach is 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 |
|---|---|---|---|
| 24 Healthy Adult Volunteers | 0 | 24 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| 24 Healthy Adult Volunteers | 0 of 24 |
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 |
|---|---|
| 24 Healthy Adult Volunteers | 2 of 24 |
Most frequent non-serious adverse event terms
| Event term | Organ system | 24 Healthy Adult Volunteers |
|---|---|---|
| Tingling Sensation | Investigations | 1 of 24 |
| Awareness of Pulse | Investigations | 1 of 24 |
The serious-adverse-event figures describe 24 participants at risk, with 0 affected by a serious adverse event and 0 deaths recorded. The registry also reports 24 participants at risk for other adverse events, with 2 affected. These are participant counts, not event rates calculated here, and the record does not provide the event terms in the serious category.
The distinction between serious and other adverse events is important when reading the entries. A count of 0 participants affected by serious events means that none were recorded in that category for this group in the registry entry; it does not establish that no symptoms or other events occurred. The two participants with other adverse events are reported separately from the serious-event count. The specific events, their timing, severity, duration, and relationship to the ultrasound exposure are not reported in the registry record.
These figures are descriptive. They do not provide a comparison with an unexposed or standard-output group, and the record describes a single-group study. The counts alone cannot establish whether an event was caused by the imaging procedure or characterize the frequency of events in a broader population. They should be read alongside the fact that the planned primary safety measure was a change in AST, for which no numerical result is reported.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a completed, single-group study was intended to assess liver enzyme measurements after shear wave elastography with conditionally increased acoustic output. It identifies a primary pre-imaging to day-7 AST mean difference and lists additional laboratory and imaging-performance outcomes. The recorded adverse-event summary includes no serious adverse events or deaths and reports two participants affected by other adverse events.
What the record does not establish is the observed AST change, the uncertainty around that change, or the results of the secondary outcomes. Those numerical results are not reported in the registry record. It is therefore not possible to determine from this entry whether measured values increased, decreased, or remained similar, or how precisely any such pattern was estimated. Missing outcome results must not be interpreted as a finding of no effect.
The study also does not provide a randomized standard-output control group. The listed comparison of standard and increased-output imaging concerns an outcome measure, but the registry description does not state enough about its analysis structure to treat it as a controlled comparison between separate groups. Without a suitable concurrent comparison and fuller analysis details, changes over time cannot automatically be attributed to the imaging setting.
The population description further limits interpretation. The title focuses on obese fatty liver disease patients, whereas the study group is described as healthy adult volunteers. The registry record does not clarify whether participants had fatty liver disease or obesity. Even a reported result in the listed group would not, without additional evidence, directly establish what would occur in the population named in the title.
Accordingly, the record supports a description of the study's aims, measurements, design, and adverse-event counts. It does not support a conclusion about the magnitude or practical importance of any AST change, the performance improvement of the imaging method, or the occurrence of a causal safety effect. Such conclusions would require the outcome estimates, their uncertainty, and fuller methods and population information.
13. Why This Trial Matters Statistically
This study is statistically notable because it places a measurement question and a safety-monitoring question within one imaging investigation. The planned outcomes include both the IQR-to-median ratio, which describes relative spread in shear wave elastography measurements, and laboratory changes intended to monitor possible bioeffects. These outcomes address different properties: measurement variability and biological change should not be treated as interchangeable evidence.
The single-group structure also makes interpretation especially dependent on clear reporting of repeated measurements and the comparison method. A pre-imaging and post-imaging difference can describe change within participants, but, in general, a single-group before-and-after comparison cannot by itself distinguish the intervention's contribution from other influences over time. The registry does not report enough analysis detail to assess that issue for the posted outcomes.
The contrast between the title's target population and the listed healthy-volunteer group is relevant to statistical generalizability. Statistical precision in one group does not automatically imply that the same estimates apply to a different population. Because the registry does not clarify the participants' liver-disease or obesity status, that population question remains unresolved.
Finally, the registry record identifies the planned primary measure and a confidence-interval convention but does not report the estimate or interval. This illustrates why endpoint names and study completion status are not substitutes for results. Effect estimates and uncertainty are necessary to assess both the scale of a change and how precisely it was measured. The adverse-event counts add descriptive context, but they cannot substitute for the missing laboratory outcomes or establish causation.
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 most immediate limitation for interpreting this record is that numerical results for the primary and listed secondary outcomes are not reported in the registry record. Without estimates and uncertainty intervals, the direction, magnitude, and precision of the laboratory changes and imaging comparison cannot be assessed. The completed status does not resolve this limitation.
The study is described as single-group, with allocation recorded as NA and no masking. No like-for-like separate control group is described. Consequently, a before-and-after change alone would not isolate the effect of increased acoustic output from other influences over time. The registry does not give enough detail to assess how the standard-versus-increased-output IQR-to-median comparison was structured.
The population description is another limitation. The title refers to obese fatty liver disease patients, while the arm description identifies healthy adult volunteers. The record does not explain the difference or report further eligibility characteristics. This makes it difficult to determine how closely the enrolled group corresponds to the population motivating the study.
The analysis plan, analysis population, missing-data approach, multiplicity strategy, and detailed measurement procedures are not reported in the registry record. The listed primary outcome specifies a mean and a 95% confidence interval, but the subtraction direction and statistical model are not described. The listed planning assumptions describe a hypothetical two-arm illustration, which should not be confused with the single-group trial design; the trial's own sample-size justification is not reported in the registry record.
The safety summary gives participant counts but does not identify the other adverse-event terms, their timing, severity, or relationship to imaging. These limitations restrict both the statistical interpretation and the scope of conclusions that can be drawn from the record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Conditionally Increased Output (CIO) Enhanced Ultrasound System — NCT05792423.
- Registry record last updated 2025-05-23; status last verified 2025-05.
- Results first posted 2025-02-14.
- 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.
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18. Record Summary
NCT05792423 is a completed, single-group device study sponsored by Massachusetts General Hospital, with 24 healthy adult volunteers listed. It evaluated a GE ultrasound system using increased acoustic output settings. The registry lists a primary endpoint of mean AST difference between before imaging and 7 days afterward, with a 95% confidence interval, and secondary outcomes involving the IQR-to-median ratio and AST, ALT, and ALP measurements at earlier follow-up times.
The registry record does not report numerical results for the primary or listed secondary outcomes, or the detailed statistical plan and analysis populations. It reports 0 participants affected by serious adverse events, 2 affected by other adverse events, and 0 deaths among 24 at risk. The title's focus on obese fatty liver disease patients differs from the arm description of healthy adult volunteers, and the record does not explain that difference.