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 A Pilot Trial of Sonoelastography for Planning Tumor-targeted Prostate Biopsy (NCT01748890), a na na study. The primary outcome is The Number of Core Biopsies in These Targeted Regions.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01748890 |
| Phase | NA |
| Condition | Prostate Cancer |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 4 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Massachusetts General Hospital |
| Results posted | Yes |
2. Clinical Question
Population
Men with prostate cancer were the intended population, as indicated by the condition and study description. The primary outcome population is described as having insufficient recruitment for analysis. The eligibility criteria and further participant characteristics are not reported in the registry record.
Intervention
Sonoelastography was the study intervention. It uses differences in ultrasound signals produced by compression of tissues with varying stiffness; those measurements can be displayed as a color overlay on an anatomic ultrasound image. The proposed use was to guide biopsy planning toward regions identified by imaging.
Comparator
The study rationale discusses targeted biopsies in relation to random prostate biopsies. However, the registry describes a single-group study and does not report a separate randomized comparator arm. Random biopsy is therefore part of the stated clinical question, not a like-for-like trial arm in the record.
Primary question
The study aimed to assess whether planned core biopsies directed by sonoelastography would intersect prostate carcinoma foci and whether the biopsy histopathology would represent the final Gleason Score from the resected prostate. The primary outcome is titled as the number of core biopsies in targeted regions, while its description also refers to biopsy intersection with carcinoma and Gleason Score. A result for these questions is not reported in the registry record.
This is a pilot question about the relationship between an imaging-guided plan and prostatectomy pathology. It asks whether locations selected before surgery correspond to carcinoma found in the resected gland, and whether the Gleason Score inferred from targeted biopsy would match the score from the prostatectomy assessment. Those are related but distinct aspects: one concerns spatial targeting, and the other concerns pathology representation.
The registry does not provide a completed comparison of targeted and random biopsy results. Its stated aim cannot be read as evidence that one approach yielded a higher detection rate or more representative pathology. The record instead indicates that recruitment was insufficient for analysis.
3. Trial Design
This was a pilot study of sonoelastography for planning tumor-targeted prostate biopsy, registered as NCT01748890. It was listed as a single-group study, with no allocation scheme and no masking. The intervention was sonoelastography, described as a device-based imaging technology. The registry lists enrollment of 4 and status as terminated. It gives a primary completion date of 2012-12 and a study start date of 2009-12.
The study description links planned elastography-targeted biopsy locations to pathology from prostatectomy. The intended assessment was to identify planned core biopsies that would intersect carcinoma foci and to consider the Gleason Score that would be obtained if biopsies sampled the targeted region. Participants were to be followed until prostatectomy pathology was available; the stated timeframe was an average 1 week. This timeframe describes the registry's planned follow-up, not a reported duration observed for each participant.
Although the rationale mentions random prostate biopsies as a comparison, the recorded design is not a randomized comparison. No separate control arm or allocation between targeted and random biopsy strategies is reported. Consequently, the study cannot be interpreted as a head-to-head randomized estimate of the difference between those approaches.
The registry identifies the primary outcome population as having insufficient recruitment for analysis. It reports one outcome measure and no analysis entries. No numerical primary outcome, participant-level pathology result, or completed analysis is reported in the registry record. The protocol details, including eligibility criteria, the planned number of participants, and the reason for termination beyond the stated recruitment shortfall, are not reported in the registry record.
In a pilot setting, the purpose may include assessing whether procedures and measurements can be carried out, but the registry does not state a specific feasibility objective or a formal progression criterion. Such details should not be inferred from the word “pilot.” The available design information supports a description of the intended imaging-pathology assessment, but not a conclusion about how well the procedure performed.
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 | Sonoelastography |
|---|---|
| STARTED | 4 |
| COMPLETED | 0 |
| NOT COMPLETED | 4 |
Reasons for not completing this period:
| Reason | Sonoelastography |
|---|---|
| Insufficient recruitment for analysis | 4 |
Analysis population for the primary outcome, as defined in the registry: insufficient recruitment for analysis
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Sonoelastography |
|---|---|---|
| Participants analysed | 0 | |
| Age, Categorical: <=18 years | — | |
| Age, Categorical: Between 18 and 65 years | — | |
| Age, Categorical: >=65 years | — | |
| Sex: Female, Male: Female | — | |
| Sex: Female, Male: Male | — | |
| Region of Enrollment: United States | participants | — |
6. Primary Endpoint
The registry lists the primary outcome as The Number of Core Biopsies in These Targeted Regions, measured over Participants will be followed until prostatectomy pathology is available (average 1 week).
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary outcome is titled “The Number of Core Biopsies in These Targeted Regions.” Its description says that correlation between elastography and prostatectomy pathology would be used to obtain the number of planned core biopsies that would intersect foci of prostate carcinoma. It also refers to the Gleason Score that would be obtained if elastographically targeted biopsies sampled the target region. The timeframe is until prostatectomy pathology is available, with an average 1 week stated in the record.
The endpoint addresses whether imaging-selected biopsy locations correspond to cancer found in the resected prostate. This is relevant to the study's stated purpose because a biopsy plan is useful only insofar as its sampled locations capture the tissue of interest. The Gleason Score component asks a related question about whether targeted biopsy pathology would represent the score assessed in the prostatectomy specimen.
The record does not fully specify how the count is defined or how the Gleason Score comparison would be summarized. It gives no actual endpoint value or analysis. The primary outcome population is marked as having insufficient recruitment for analysis, so the registry does not establish how many planned cores intersected carcinoma or whether the biopsy score represented the prostatectomy score.
The endpoint should therefore be read as a planned pathology-correlation measure, not as a demonstrated diagnostic performance result. It does not, by itself, provide a sensitivity, specificity, detection rate, or estimate of agreement; these quantities are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive fact is that the registry reports insufficient recruitment for analysis. Enrollment was 4, and the study status is terminated. The record lists a primary outcome measure but gives no numerical result and no analysis entries. Accordingly, there is no reported estimate from which to judge the degree of correspondence between sonoelastography-targeted biopsy locations and carcinoma foci, or between targeted biopsy Gleason Score and prostatectomy Gleason Score.
The study rationale describes a comparison of targeted biopsy planning with random biopsy, but the registry classifies the design as single group and does not report a randomized control arm. This matters because the stated comparison does not become a controlled treatment-effect estimate merely because two strategies appear in the study rationale. The record does not establish a between-group contrast, and no comparative effect estimate is reported.
In general, estimates from a small study tend to be imprecise because each observation can have substantial influence on the result. That general concern is especially relevant when the record itself says recruitment was insufficient for analysis. However, no confidence interval or other precision measure is reported, so the actual uncertainty around any endpoint estimate cannot be quantified from the registry record. No effect estimate is available to assess.
The lack of a reported analysis also means that statistical significance cannot be interpreted. The record contains no p-value, model estimate, or reported hypothesis test for the primary outcome. There is no basis for describing the findings as statistically significant or non-significant. More fundamentally, there is no analyzable primary result reported to support either description.
The study's imaging-pathology rationale remains a research question rather than a conclusion. The registry describes the intended use of elastography and the pathology correlation to be examined, but it does not report whether the planned targeted regions corresponded to cancer in the prostatectomy specimen. Nor does it report whether the targeted-biopsy Gleason Score matched, or otherwise represented, the final score.
These omissions should not be replaced with assumptions about what happened among enrolled participants. The registry does not provide individual observations, reasons for missing endpoint information, or a participant flow account. It also does not report whether any exploratory or interim analyses occurred; the analysis count is zero. The appropriate reading is therefore descriptive and limited: a small, terminated pilot is recorded, but the primary outcome is not available for statistical interpretation.
9. Statistical Methods Explained
Statistical methods are difficult to evaluate when the record contains no analysis result. The registry describes a single-group pilot with enrollment of 4, an intended pathology-correlation outcome, and insufficient recruitment for analysis. It lists no analysis entries. The statistical concepts below explain what would ordinarily be needed to interpret a study of this kind; they do not describe analyses documented as having been completed for this trial.
What would the estimand represent?
In general, an estimand is the precisely defined quantity a study seeks to estimate. For this study, the broad scientific aim concerns the correspondence between locations planned by sonoelastography and carcinoma identified in prostatectomy pathology, as well as the relationship between biopsy Gleason Score and the final score. A usable estimand would need to specify the analysis population, the unit of observation, the definition of a targeted region or core, and how correspondence or score representation is summarized. The registry does not report these operational details. It names a count of core biopsies in targeted regions and describes pathology correlation, but the exact statistical summary is not stated.
How should a count endpoint be understood?
In general, a count records how many events or items meet a defined criterion. Count analyses depend on a clear definition of what is counted and on how observations are grouped. For this outcome, the record refers to planned core biopsies that would intersect carcinoma foci. It does not state whether the intended result is a raw count for each participant, a count across the study, or another summary. Those are different quantities and should not be treated as interchangeable.
Counts can also vary more than a simple probability model expects, a feature called over-dispersion. General methods for count data may account for that extra variability when suitable data and a defined analysis are available. The registry does not identify a count model or report data with which to assess over-dispersion. It would therefore be inappropriate to attribute a particular model to this study.
What does pathology correlation require?
In general, a correlation or agreement question needs paired measurements and a prespecified way to compare them. A location-based assessment would need a rule for determining whether a planned core intersects a carcinoma focus in the resected gland. A score-based assessment would need a rule for comparing the biopsy Gleason Score with the prostatectomy assessment, including how differences would be treated. Correlation and agreement are not identical: two measures may move together without yielding the same values. The registry describes the intended relationship but does not report the scoring rules, paired observations, or a statistical measure of agreement.
What can a confidence interval add?
In general, a confidence interval expresses the uncertainty around an estimated quantity under the assumptions of the statistical procedure used. Its width reflects both the observed information and the method. A confidence interval could help show whether an estimate is precise enough to be informative, but it cannot compensate for an undefined endpoint or an unsuitable design. No estimate or confidence interval for the primary outcome is reported in the registry record, so precision cannot be assessed numerically.
Why does the design matter?
In general, a randomized comparison can help separate the effect of an intervention strategy from differences between groups, provided the trial is properly conducted and analyzed. Here, the registry lists a single-group model, no allocation, and no masking. The mention of random biopsy in the study rationale does not establish a randomized comparison arm. The record therefore does not support a randomized estimate comparing strategies. The pathology-correlation aim can still be described, but it is distinct from a controlled estimate of comparative effectiveness.
How should planning calculations be read?
In general, sample-size calculations are planning exercises based on assumptions about the effect to detect, variability, significance level, allocation, and statistical method. They are not evidence that an effect was observed, and they are not “observed power.” The registry's planning assumptions describe a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the target effect expressed as a fraction of an observed effect. The record explicitly characterizes this as a planning illustration rather than the trial's own design. It does not provide a reported primary effect estimate or numerical planning results in the information recorded for this trial. These assumptions should not be mistaken for a completed two-arm design, particularly given the recorded single-group model.
Because no primary analysis is reported, there is no basis to assess model fit, assumptions, missing-data handling, or multiplicity adjustments. A statistical plan, including any interim analyses or prespecified inferential procedures, is not reported in the registry record. Those absences limit methods appraisal; they do not establish that a particular method was or was not used outside the registry entry.
10. Multiplicity, Missing Data and Analysis Populations
Multiplicity arises when a study evaluates more than one outcome, comparison, or analysis and makes several inferential claims. In general, testing multiple hypotheses can increase the chance of a false-positive finding unless the analysis plan addresses that issue. The registry lists one outcome measure, but its description encompasses both the number of planned cores intersecting carcinoma and the Gleason Score expected from targeted sampling. It does not explain whether these are separate endpoint components, how they would be prioritized, or whether any multiplicity procedure was planned.
No analysis entries are reported, and the registry does not provide a statistical analysis plan or results. Whether any interim analyses, subgroup analyses, or additional exploratory analyses occurred is not reported in the registry record. No adjustment for multiplicity is described, but the absence of a description does not establish what may have been done outside the record.
The primary outcome population is identified as having insufficient recruitment for analysis. The record does not give participant-level outcome availability or explain the status of the endpoint for each enrolled participant. It therefore does not establish whether endpoint data were missing, whether pathology was unavailable, or whether any observations were excluded. Missing-data assumptions and methods are not reported in the registry record.
The analysis population is also not described beyond the statement that recruitment was insufficient for analysis. There is no reported intention-to-treat or per-protocol analysis set, nor a definition of inclusion for any endpoint analysis. These gaps prevent an assessment of whether the population used for analysis matched the intended population or whether missingness could have affected the result. Since no primary estimate is reported, the impact of multiplicity or missing data cannot be quantified.
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 |
|---|---|---|---|
| Sonoelastography | 0 | 4 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Sonoelastography | 0 of 4 |
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 |
|---|---|
| Sonoelastography | 0 of 4 |
The registry records adverse-event figures for the Sonoelastography group. It lists 4 at risk for serious adverse events and 0 affected; for other adverse events, it lists 4 at risk and 0 affected. Deaths are recorded as 0. No serious adverse-event terms are listed.
These figures are counts in the registry record, not evidence that risk was absent. In general, zero recorded events in a small study cannot rule out uncommon events, and the ability to characterize safety depends on the amount and completeness of follow-up. The record does not provide event definitions, collection procedures, severity details, or participant-level follow-up for safety. It also does not report how adverse events were attributed or whether any events led to discontinuation.
The listed figures should therefore be read narrowly: no serious or other adverse events, and no deaths, are recorded among those listed as at risk. They do not establish that the procedure has no safety concerns, and they do not support a comparative safety assessment because a separate comparator arm is not reported.
12. What the Result Does, and Does Not, Mean
The registry record documents a pilot study of sonoelastography as a method for planning tumor-targeted prostate biopsy. Its scientific question was whether planned targeted cores would intersect carcinoma found in prostatectomy pathology and whether targeted biopsy Gleason Score would represent the final score from the resected prostate. The entry indicates that recruitment was insufficient for analysis and does not report a primary outcome result.
That means the record does not show how often planned cores corresponded to carcinoma, how the biopsy score compared with prostatectomy pathology, or how precisely either quantity was estimated. No result should be inferred from the study rationale, the existence of an outcome measure, or the enrollment entry. The registry also does not provide a completed randomized comparison against random biopsy. Its single-group design cannot be treated as a head-to-head trial simply because random biopsy appears in the stated aim.
In general, a pilot can help identify whether a research approach is practicable and can inform later study planning. However, the registry does not state specific feasibility criteria or report a formal feasibility outcome. It records termination and insufficient recruitment for analysis, but does not provide further detail about why recruitment fell short or what was learned operationally.
The safety record lists no serious adverse events, other adverse events, or deaths among the group reported at risk. Those counts describe what is recorded; they do not rule out events that a small study would be unable to characterize reliably, and they do not establish comparative safety.
Overall, the trial record documents an intended imaging-to-pathology assessment rather than an interpretable estimate of diagnostic performance. It does not show that sonoelastography-guided planning improved biopsy targeting, nor does it show that it failed to do so. The primary result is not reported in the registry record, so neither conclusion is supported.
13. Why This Trial Matters Statistically
This study illustrates an important distinction between a biologically plausible measurement and a statistically interpretable result. Sonoelastography is described as measuring tissue elasticity and displaying tissue stiffness over conventional ultrasound anatomy. The clinical question is whether regions selected by that imaging information correspond to carcinoma in the resected prostate. Establishing that link requires clear definitions of the target, the biopsy core, and the pathology match, followed by a reported analysis of paired observations.
The registry also highlights why design labels matter. The rationale refers to random biopsy, but the recorded model is single group and no allocation is listed. A study question may name a comparator without actually including a randomized comparator arm. Recognizing that distinction prevents a pathology-correlation study from being read as a controlled comparison of strategies.
The record further shows the limits of an uncompleted or unanalyzable pilot for estimating effects. Enrollment was 4, and the primary outcome population is marked as insufficient for analysis. Without a reported estimate and its precision, readers cannot determine the size or reliability of any relationship between imaging targets and pathology. In general, a small pilot may be useful for developing procedures, but it cannot substitute for an adequately described analysis when the aim is to estimate performance.
Finally, the registry entry demonstrates why outcome titles and descriptions should align. The primary outcome title refers to a count of core biopsies in targeted regions, while its description includes both intersection with carcinoma and the Gleason Score obtained under targeted sampling. Clear endpoint definitions help determine what is counted, what constitutes a match, and what statistical summary answers the scientific question. These details are not fully reported in the record.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The most consequential limitation is recorded directly: recruitment was insufficient for analysis. Enrollment was 4, the study is marked terminated, and no primary result or analysis entry is reported. The planned pathology-correlation question therefore has no interpretable numerical answer in the registry record.
The design also limits comparative interpretation. Although the stated rationale refers to random prostate biopsies, the study is listed as single group with no allocation. The record does not describe a randomized control arm or a direct comparison. Any claim about superiority or inferiority relative to random biopsy would go beyond the recorded design and results.
Endpoint definition is another limitation. The title refers to the number of core biopsies in targeted regions, while the description includes the number of planned cores intersecting carcinoma and the Gleason Score that would be obtained from targeted sampling. The record does not state a precise analysis unit, method for defining a successful intersection, or summary for score representation. It also gives no actual pathology observations.
Participant eligibility criteria and baseline characteristics are not reported in the registry record. Nor are participant flow, outcome availability, missing-data methods, or the statistical analysis plan described. The stated average follow-up timeframe does not provide individual follow-up information. The reason for termination beyond the recruitment shortfall is not reported in the registry record.
These limitations mean that the record cannot establish diagnostic performance, precision, comparative effect, or the generalizability of findings. The absence of a reported result should not be interpreted as a negative finding; it leaves the primary question unanswered in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Pilot Trial of Sonoelastography for Planning Tumor-targeted Prostate Biopsy — NCT01748890.
- Registry record last updated 2017-10-20; status last verified 2017-10.
- Results first posted 2014-05-20.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT01748890 records a pilot trial of sonoelastography for planning tumor-targeted prostate biopsy. The study was listed as single group, with no allocation and no masking. It enrolled 4 and is marked terminated. The stated primary completion date is 2012-12.
The study aimed to relate planned elastography-targeted core locations to prostatectomy pathology, including whether cores would intersect carcinoma and what Gleason Score targeted sampling would yield. Participants were to be followed until prostatectomy pathology was available, with an average 1 week stated as the timeframe.
The registry identifies the primary outcome population as having insufficient recruitment for analysis. It lists no analysis entries and reports no numerical primary outcome result. The rationale mentions random biopsy, but no randomized comparator arm is recorded. Safety figures list 0 serious adverse events, 0 other adverse events, and 0 deaths. These entries describe the registry record, not a completed comparative estimate of biopsy performance or safety.