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 Novel Use of an Enhanced Fluoroscopic Imaging Device to Reduce Radiation Exposure and Operative Time During Intramedullary Nailing of Hip Fractures (NCT02856828), a randomized na study. The primary outcome is Radiation Exposure to Patient During Intramedullary Nail Placement for Treatment of Hip Fractures as Measured by Dosimeter Badge.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02856828 |
| Phase | NA |
| Condition | Radiation Exposure |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 5 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Duke University |
| Results posted | Yes |
2. Clinical Question
Population
People undergoing intramedullary nail placement for treatment of hip fractures. The registry record lists five participants enrolled overall. It does not provide further participant characteristics or describe the population included in the primary outcome analysis.
Intervention
Intraoperative use of a novel digital image enhancement (DIE) technology. The study aimed to evaluate whether this approach could reduce radiation exposure to the patient and surgical staff, and whether it could improve image quality, reproducibility of desired images, and total operative time.
Comparator
Standard intraoperative imaging, without the DIE technology described for the intervention group. The registry record describes this as a randomized, parallel-group comparison and lists no masking.
Primary question
What amount of radiation exposure to the patient occurs during intramedullary nail placement, as measured by a dosimeter badge intraoperatively, in the DIE group compared with the standard-imaging control group? The registry record does not report a single between-group result for this endpoint.
The clinical question is about a procedural imaging device and the radiation exposure associated with its use, rather than a medication or a comparison of longer-term clinical outcomes. The stated primary outcome concerns radiation exposure to the patient. The study description also identifies exposure to surgical staff as an aim, but the primary outcome specified in the record is patient exposure. Image quality, reproducibility of desired images, and operative time are listed as secondary outcomes.
The registry record does not report a single numerical estimate of the difference between groups for the primary outcome. It notes that the primary outcome has several categories or time points and was not reduced to one comparison. Consequently, the record does not establish how the observed radiation measurements compared between the groups, nor how precisely any such difference was estimated.
3. Trial Design
The registry describes a randomized, parallel-group study with no masking. Participants were assigned to a DIE group, in which the enhancement technology was used intraoperatively, or a control group, in which standard intraoperative imaging was used. Random allocation is intended, in general, to reduce systematic differences between groups at the point of assignment. With no masking, participants and clinical personnel were not described as blinded to the assigned imaging approach; the registry record does not state whether outcome assessors were masked.
The recorded enrollment was five. The record lists two participants at risk in the DIE group and three in the control group for the adverse-event reporting. These group counts describe the safety record and should not automatically be assumed to define the analysis population for every outcome. The number included in each efficacy analysis is not reported in the registry record.
The study start date is 2017-03-01, and the primary completion date is 2018-02-06. Its status is recorded as terminated. The reason for termination is not reported in the registry record. The phase is recorded as NA. The sponsor is Duke University.
The stated purpose was to evaluate whether DIE could reduce radiation exposure to the patient and surgical staff during standard intramedullary nail placement for hip fractures. The study also sought to assess image quality and reproducibility of desired images, and total operative time. The registry lists five outcome measures but reports zero analyses. A protocol-level description of the allocation procedure, planned enrollment rationale, follow-up procedures, or any interim analyses is not reported in the registry record.
The design identifies the intended comparison, but the small recorded enrollment and lack of a single reported primary-outcome comparison limit what can be learned from the registry entry. Randomization describes how assignment was intended to occur; it does not, by itself, ensure that the groups are balanced in a very small study or provide an estimate of treatment effect.
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 | Digital Image Enhancement (DIE) Group | Control Group |
|---|---|---|
| STARTED | 2 | 3 |
| COMPLETED | 2 | 3 |
| NOT COMPLETED | 0 | 0 |
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: Hip fracture patients only, not surgeons
| Characteristic | Unit | Digital Image Enhancement (DIE) Group | Control Group | Total |
|---|---|---|---|---|
| Participants analysed | 2 | 3 | 5 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 0 | 1 | 1 |
| Age, Categorical: >=65 years | Participants | 2 | 2 | 4 |
| Sex: Female, Male: Female | Participants | 2 | 2 | 4 |
| Sex: Female, Male: Male | Participants | 0 | 1 | 1 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: United States | participants | 2 | 3 | 5 |
6. Primary Endpoint
The registry lists the primary outcome as Radiation Exposure to Patient During Intramedullary Nail Placement for Treatment of Hip Fractures as Measured by Dosimeter Badge, measured over intraoperatively.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | mGy |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is radiation exposure to the patient during intramedullary nail placement for treatment of hip fractures. It is measured with a dosimeter badge, with the unit recorded as mGy, and the timeframe is intraoperative. A dosimeter is used to measure radiation exposure rather than relying on a subjective rating or recollection.
In general, an endpoint should correspond to the question a study is designed to address. Radiation exposure is directly relevant to the stated aim of assessing whether an imaging technology changes exposure during the procedure. The endpoint’s meaning depends on how the badge was positioned, how readings were recorded, and how multiple readings or time points were combined. Those details are not reported in the registry record.
The registry record does not provide a single numerical outcome or between-group estimate for this endpoint. It notes that the primary outcome includes several categories or time points and was not reduced to one comparison. Therefore, the endpoint is defined, but its comparative result and precision cannot be interpreted from the posted registry results. The registry also does not report a patient-exposure result that can be used to judge the size or direction of a difference between the imaging approaches.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical limitation is that the registry record does not provide a single interpretable comparison for the primary radiation endpoint. It identifies the measurement as patient exposure recorded by dosimeter badge during the procedure, in mGy, but the outcome has several categories or time points and is not reduced to one comparison. The numerical measurements, a summary estimate, and an uncertainty interval are not reported in the registry record. No conclusion about the direction or magnitude of a group difference can therefore be drawn from this entry.
The record lists five participants enrolled and identifies two participants in the DIE group and three in the control group in its adverse-event information. The efficacy analysis populations are not reported in the registry record. Even if outcome values were available, results from such a small enrolled group would generally be sensitive to the measurements of individual participants. This is a general statistical consideration, not an estimate of the precision of this study’s result.
The registry lists five outcome measures and zero analyses. That means the record, as posted, does not provide inferential results such as a reported test or model-based estimate. It also does not report a confidence interval or p-value for the primary comparison. A confidence interval, in general, describes a range of values compatible with the data and analysis under specified assumptions; without a reported estimate and interval, the precision of any effect cannot be assessed.
The terminated status is important context, but the reason for termination is not reported in the registry record. It would be inappropriate to infer that the study stopped for a particular reason, or that the termination itself indicates a favorable or unfavorable finding. The record also does not state whether recruitment ended as planned, whether outcome collection was complete, or whether results were analyzed before termination.
The study’s stated objectives include staff exposure, image quality, reproducibility, and operative time in addition to patient radiation exposure. The registry record does not provide a single comparative result for these objectives either. Thus, the posted information describes the research question and design more clearly than it describes the findings. It does not allow a reader to quantify an effect, judge its uncertainty, or compare the primary outcome with the secondary outcomes.
Any planning illustrations based on an observed effect should be interpreted cautiously in this setting. Such illustrations describe hypothetical sample sizes under specified assumptions; they are not observed power and do not replace a reported outcome estimate. Because a single observed effect is not available for the primary comparison, the registry record does not support a substantive interpretation of a planning calculation as evidence about the device’s performance.
9. Statistical Methods Explained
What does randomization contribute?
In general, randomization assigns participants to study groups using a chance-based process. Its purpose is to reduce the likelihood that group assignment is systematically related to participant characteristics that might also affect outcomes. Randomization does not guarantee that groups will be similar on every characteristic, especially when enrollment is small. The registry identifies this study as randomized and parallel-group, but the precise sequence-generation and allocation-concealment procedures are not reported in the registry record.
A parallel design compares groups assigned to different approaches over the study period, rather than having each participant receive both approaches in sequence. Here, the named groups are DIE and standard intraoperative imaging. The record does not provide further detail about how procedures, operators, or measurement conditions were standardized.
How should the endpoint measurement be understood?
The primary outcome is a count-type measure of radiation exposure to the patient, recorded by dosimeter badge in mGy during the operation. The registry classifies its result as a number, but does not report a single value or comparison. General statistical practice requires the analysis to match the form and distribution of the measured outcome. Radiation readings may have different distributions from outcomes such as a yes-or-no event, but the registry does not report enough measurement detail or outcome data to determine what model would be suitable.
For any continuous or count-like measurement, a useful comparison usually includes a group summary and an estimate of the between-group difference or another clearly defined contrast. An uncertainty interval can then convey the range of values compatible with the data under the analysis assumptions. Those estimates are not reported for the primary endpoint in the registry record. It is therefore not possible to assess the observed variability, the estimated contrast, or the precision of that contrast.
Why does the outcome structure matter?
The registry record says the primary outcome has several categories or time points and was not reduced to one comparison. In general, repeated readings or multiple categories require a clear rule for defining the outcome and the comparison of interest. Possible analysis choices can target different questions, such as a particular time point, an overall pattern, or a summary across measurements. These are general examples, not descriptions of the analysis used in this study. The registry record does not specify which approach was planned or used.
When observations are taken repeatedly from the same participant, they may be related rather than independent. General statistical methods account for that dependence where necessary; treating related observations as independent can make uncertainty estimates unreliable. The registry does not report the structure of the readings or an analysis that addresses repeated measures, so no claim can be made about how this issue was handled.
What does the missing analysis information imply?
The registry lists zero analyses. It does not report a statistical test, model, estimate, p-value, confidence interval, or analysis population for the primary outcome. The statistical analysis plan, handling of missing outcome measurements, and any adjustment for baseline variables are not reported in the registry record. These absences do not show that no analysis occurred; they mean that a specific analysis cannot be evaluated from the registry entry.
In general, a p-value addresses how compatible data are with a specified null model and assumptions; it does not measure the size or clinical importance of an effect. An interval estimate adds information about uncertainty around an estimate. Neither statistic can be reconstructed responsibly when the needed outcome summaries and analysis details are absent.
How should sample-size illustrations be read?
General sample-size planning asks how many participants would be needed to detect a prespecified effect with a chosen error rate and power, given assumptions about variability and allocation. The registry record describes planning illustrations based on fractions of an observed effect, a two-sided significance level of 0.05, equal allocation, and a normal approximation. For non-time-to-event outcomes, such planning is expressed as participants per arm; for time-to-event outcomes, it is expressed as total events. These are planning conventions, not observed results.
The stated illustrations are not the trial’s own design justification and must not be read as observed power. The trial’s sample-size justification is not reported in the registry record. A planning estimate based on an observed effect can also be unstable when the observed effect comes from very little data. Since no single primary effect is reported, the registry record does not permit an independent assessment of the assumptions or meaning of a primary-outcome planning illustration.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists five outcome measures, including patient radiation exposure as the primary outcome and image quality, reproducibility of desired images, and operative time as secondary outcomes. It does not report an analysis plan specifying which secondary outcomes were tested, how many comparisons were made, or whether any adjustment for multiple comparisons was planned. Multiplicity handling is therefore not reported in the registry record.
In general, testing several outcomes or time points creates more opportunities for apparently notable findings to occur by chance. Methods that control or describe this issue can help readers distinguish a prespecified primary comparison from exploratory findings. Without the planned testing hierarchy or analysis details, it is not possible to assess how multiplicity was addressed. The record’s note that the primary endpoint has multiple categories or time points makes a clearly defined comparison especially important, but the registry does not identify one.
Missing-data procedures and analysis populations are also not reported in the registry record. The posted entry does not say whether all enrolled participants had complete measurements, how unavailable readings were treated, or whether the analysis followed assigned groups. It does not describe exclusions or reasons for missingness. These details matter because missingness can affect both the estimated group comparison and its uncertainty.
General analysis principles distinguish the group to which participants were assigned from the group whose observations are included in a particular analysis. The registry’s adverse-event counts do not establish the analysis population for the primary or secondary outcomes. No conclusion about intention-to-treat analysis, per-protocol analysis, or another population can be made from the record.
Interim analyses and stopping criteria are not reported in the registry record. Given the terminated status, that absence prevents an assessment of whether stopping was related to a planned rule, recruitment, logistics, or another circumstance. The reason for termination is not reported, so no explanation should be inferred.
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 |
|---|---|---|---|
| Digital Image Enhancement (DIE) Group | 0 | 2 | 0.0% |
| Control Group | 0 | 3 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Digital Image Enhancement (DIE) Group | 0 of 2 |
| Control Group | 0 of 3 |
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 |
|---|---|
| Digital Image Enhancement (DIE) Group | 0 of 2 |
| Control Group | 0 of 3 |
The registry reports zero serious adverse events and zero deaths in both groups. The DIE group lists two participants at risk, and the control group lists three participants at risk. The record also lists zero other adverse events in each group. These are the event counts recorded in the registry; they do not establish that no unrecorded or unreported events occurred.
With only the listed participants at risk, the safety counts are descriptive and provide limited information about uncommon events. In general, observing no events in a small group does not demonstrate that an event cannot occur or precisely estimate its frequency. The registry does not provide event definitions, the duration or completeness of safety follow-up, or details of how events were collected and classified. The serious adverse-event terms list is empty.
These figures should be kept separate from the radiation endpoint. They describe reported adverse-event counts, not dosimeter measurements or an analysis of radiation exposure. They also should not be interpreted as a comparison demonstrating that one imaging approach is safer. The registry record does not report a statistical analysis of the safety data, and the small numbers make a comparative safety interpretation especially uncertain.
12. What the Result Does, and Does Not, Mean
The registry entry establishes that a randomized, parallel-group study was registered to compare intraoperative DIE with standard imaging during intramedullary nail placement for hip fractures. It identifies patient radiation exposure measured by dosimeter badge during the procedure as the primary outcome. It also records secondary interests in image quality, reproducibility of desired images, and operative time.
What the record does not establish is the size or direction of a difference in radiation exposure between the groups. It reports no single primary-outcome comparison, numerical estimate, uncertainty interval, or p-value. The recorded outcome structure includes several categories or time points, and the registry does not reduce these to one comparison. The posted results therefore cannot show whether measured exposure was higher, lower, or similar between the groups, or how precisely any difference was estimated.
In general, evidence about an intervention depends not only on the direction of an observed estimate but also on its uncertainty, the quality of measurement, and the design and completeness of the analysis. None of those considerations can be fully evaluated for the primary endpoint from the registry results. The small recorded enrollment further means that any available observations would need careful interpretation, but the registry does not provide the underlying measurements or analysis needed to judge them.
The terminated status does not, on its own, explain what happened or imply anything about the results. The reason for termination, the completeness of outcome collection, and the analysis populations are not reported in the registry record. Nor does the absence of reported analyses prove that no analysis was conducted; it means the record does not provide results that can be assessed statistically.
The appropriate reading is therefore narrow: the registry describes a study question and a randomized comparison, but does not provide enough outcome information to support a quantitative conclusion about the primary endpoint or the listed secondary objectives. It neither demonstrates an effect nor demonstrates its absence.
13. Why This Trial Matters Statistically
This study raises a statistical question that often arises in procedural research: how should an objective measurement be compared when it may be collected at several categories or time points? A clearly defined endpoint and contrast are essential. If a registry identifies a primary measurement but does not specify one summary comparison, readers cannot connect the study question to a single effect estimate.
The issue matters because a measurement alone is not a comparative result. To understand a randomized study, readers need group-specific outcome summaries, a defined contrast, and information about uncertainty. Those elements allow an assessment of whether the estimate is precise, whether it is compatible with a range of effects, and how it relates to the study’s stated question. The registry record does not report them for the primary radiation endpoint.
Small studies can be informative in some contexts, including feasibility or measurement development, but their estimates may be imprecise. General statistical reasoning cautions against treating a sparse record of events or a single unstable estimate as definitive. Here, the recorded enrollment is five, and the reason for termination is not reported. Without the analysis and outcome details, the intended role of the study cannot be established from the registry record.
The entry also illustrates why registration details and posted results serve different purposes. The record describes randomization, intervention groups, endpoints, and study status, while its results do not provide a usable primary comparison. A complete, transparent account would allow readers to distinguish prespecified outcomes from additional analyses and to evaluate missing data, multiplicity, and uncertainty. Those details are not reported in the registry record.
Statistically, the study is relevant as an example of a defined clinical question without an interpretable reported estimate. The central lesson is not about the performance of either imaging approach; it is that design labels and endpoint names alone cannot establish an effect. The comparison must be accompanied by results and enough analysis detail to assess their meaning.
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 foremost limitation of the registry record is that it does not provide a single numerical comparison for the primary endpoint. It states that the outcome involves several categories or time points but does not report how those were summarized or analyzed. The underlying radiation measurements, group summaries, effect estimate, and uncertainty are not reported in the registry record.
Enrollment was five, and the study is recorded as terminated. The reason for termination is not reported. The entry does not state whether enrollment reached its intended target, whether all planned measurements were obtained, or whether termination affected data collection. The planned enrollment and its justification are also not reported in the registry record.
Important measurement details are unavailable, including how the dosimeter badge was positioned, how readings were handled across time points, and what rules defined usable measurements. The record does not report the analysis population, missing-data procedures, statistical model, or any adjustments. It also does not explain whether outcome assessors were masked, although the study is listed as having no masking.
There is no reported inferential analysis for the primary or secondary outcomes. The registry lists five outcome measures and zero analyses, and does not provide p-values or confidence intervals. As a result, neither effect magnitude nor precision can be evaluated. Multiple outcomes and time points may complicate interpretation, but any multiplicity strategy is not reported in the registry record.
The safety information consists of small group counts with no reported adverse events or deaths. Definitions and follow-up details are absent, limiting what those counts can establish. Finally, the record’s stated aim includes radiation exposure to surgical staff, but the primary endpoint described is patient exposure; a separate comparative staff-exposure result is not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Novel Use of an Enhanced Fluoroscopic Imaging Device to Reduce Radiation Exposure and Operative Time During Intramedullary Nailing of Hip Fractures — NCT02856828.
- Registry record last updated 2019-10-15; status last verified 2019-10.
- Results first posted 2019-10-01.
- 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
The registry record describes a randomized, parallel-group study with no masking, comparing intraoperative digital image enhancement with standard imaging during intramedullary nail placement for hip fractures. Duke University is listed as sponsor. The recorded enrollment is five, and the study status is terminated. The start date is 2017-03-01, and the primary completion date is 2018-02-06.
The primary outcome is patient radiation exposure measured by dosimeter badge intraoperatively, with mGy as the unit. Secondary outcomes include image quality, reproducibility of desired images, and operative time. The record lists five outcome measures and zero analyses. It does not report a single primary-outcome comparison, statistical estimate, or uncertainty interval. The reason for termination, analysis populations, missing-data handling, and statistical analysis plan are not reported in the registry record. The posted entry therefore describes the intended study question and design but does not support a quantitative interpretation of the primary result.