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 LSFG-SKIN, Laser Speckle Flowgraphy (NCT03660618), a na na study. The primary outcome is Imaging Blood Flow.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03660618 |
| Phase | NA |
| Condition | Hypertension, Heart Failure, Vascular Ischemia |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 1 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Randy Kardon |
| Results posted | Yes |
2. Clinical Question
Population
The record describes “Clinic Subjects” from cardiology, dermatology, endocrine, neurology, psychiatry, surgery and ophthalmology. The primary-outcome description says one subject was tested.
Intervention
Laser speckle flowgraphy, listed as a device intervention, was used to image blood flow in tissue.
Comparator
No separate comparator group is reported. The study is listed as single-group, and allocation is recorded as NA.
Primary question
The project aimed to quantify regional skin blood flow, including normal and abnormal flow, at baseline and over time in response to treatment or environmental changes. The primary outcome is titled “Imaging Blood Flow.”
The broad project description refers to skin at different body regions, including the face, extremities, burns and wounds. It also names temperature, light and pressure as environmental changes of interest. These are aims in the brief summary, not evidence that each region or condition was assessed in the completed record.
The record lists a wide range of conditions, including hypertension, heart failure, vascular ischemia, burns, chemotherapy effect, radiation injuries, uveitis, scleritis, multiple sclerosis, autonomic neuropathy, stroke, intracranial hemorrhages, TIA, migraine, headache and pain. The record does not report condition-specific results or establish that people with each listed condition were studied.
The primary-outcome description states that the device had to be returned after the company went out of business, that the data were not measurable, and that repeat testing was not possible. Consequently, the registry record does not provide an analyzable estimate answering the question about skin blood flow.
3. Trial Design
NCT03660618 is recorded as a single-group study, with allocation listed as NA and masking listed as none. The phase is recorded as NA. The registry record does not describe a randomized comparison or a separate control arm. The arm is titled “Clinic Subjects” and its description lists subjects from several clinical specialties.
Enrollment is recorded as 1. The study start date is 2017-05-23, the primary completion date is 2019-03-02, and the status is terminated. These registry entries describe the study record; they do not establish that the planned observations were completed. The primary-outcome text specifically says that one subject was tested, that the data were not measurable, and that repeat testing was not possible after the device was returned.
The listed intervention is laser speckle flowgraphy, classified as a device. The primary outcome is “Imaging Blood Flow,” with a timeframe of one visit. The record does not report a formal comparator or a between-group treatment contrast. A single-group design can describe measurements made within the group, but without a stated comparator it cannot by itself provide a like-for-like comparison between treatment groups.
The registry record does not report a detailed protocol, recruitment process, eligibility criteria, or a statistical analysis plan. It also does not report a sample-size justification. These details should not be inferred from the broad list of conditions, the specialty descriptions or the project summary. The sponsor is recorded as Randy Kardon.
Because the planned blood-flow data were not measurable and repeat testing could not be done, the study record does not yield a usable primary-outcome result. Its terminated status and single-group structure are important context when interpreting the enrollment and the absence of 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 | Clinic Subjects |
|---|---|
| STARTED | 1 |
| COMPLETED | 1 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: One subject tested before device had to be returned due to company going out of business. Data was not measurable and no repeat testing was possible as device was returned.
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: female
| Characteristic | Unit | Clinic Subjects |
|---|---|---|
| Participants analysed | 1 | |
| Age, Continuous | years | 55 |
| Sex: Female, Male: Female | Participants | 1 |
| Sex: Female, Male: Male | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 1 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
6. Primary Endpoint
The registry lists the primary outcome as Imaging Blood Flow, measured over One visit.
| 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 “Imaging Blood Flow,” with a timeframe of one visit. The project description frames imaging as a way to quantify skin blood flow regionally, and to examine normal and abnormal flow at baseline and over time in response to treatment or environmental changes. In general, an imaging endpoint is intended to turn a physiological feature into an observation that can be compared across regions or occasions. Such measurements can be useful for describing patterns, provided that the acquisition and measurement produce interpretable data.
The registry record does not report a measurement unit, a parameter definition or a dispersion measure for this endpoint. Those details are not reported in the registry record, so the precise numerical scale and the intended summary of the imaging measurement cannot be characterized. The one-visit timeframe is the timeframe attached to the primary outcome; it does not establish that repeated measurements were successfully obtained.
Most importantly, the outcome description says that the one subject tested had data that were not measurable. The device was returned and repeat testing was not possible. This means the record does not provide an analyzable blood-flow value or a usable estimate of change. An outcome that could not be measured should not be interpreted as a measured value of zero, nor as evidence that blood flow did not change.
In general, an endpoint is useful only when its observations can be interpreted in relation to the question it is intended to answer. Here, the stated endpoint and rationale describe the intended measurement, while the registry record documents that the intended measurement did not yield usable data.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record documents a study intended to image regional skin blood flow with laser speckle flowgraphy. Its central statistical limitation is not uncertainty around an observed effect, but the absence of a measurable primary-outcome result. The primary-outcome description says one subject was tested and that the data were not measurable. It also says repeat testing was not possible after the device was returned. Therefore, no numerical blood-flow estimate, treatment-related change or comparison can be interpreted from this record.
This distinction matters. A value of zero would be a measurement with a numerical result; unmeasurable data are not such a result. Likewise, a lack of an estimated change is not evidence that the true change was absent. The record does not offer an effect estimate with a confidence interval, a test statistic or a p-value for the primary outcome. These are not reported in the registry record.
The single-group design also limits the kinds of conclusions the study could support. A single group can be used to describe observations in that group, but it does not create a concurrent control comparison. The record lists allocation as NA and masking as none, and it does not report a separate comparator group. Accordingly, the record does not support a randomized, like-for-like comparison between groups.
The enrollment is recorded as 1, while the primary-outcome description explicitly reports one subject tested. With no measurable endpoint data, the record cannot establish the distribution of blood-flow values or the variability of the measurement. It also cannot show whether the imaging could distinguish among body regions, clinical conditions or responses to treatment or environmental changes. Those aims appear in the project description, but corresponding analyzed results are not reported in the registry record.
The study status is terminated. The reason described for the inability to obtain a usable endpoint is that the device had to be returned after the company went out of business, preventing repeat testing. That information explains why the endpoint could not be completed as described; it does not provide evidence about the performance of the device or the underlying biological question.
No analyses are listed in the registry record. Therefore, the interpretation should remain descriptive: the study was registered to image blood flow, but the posted primary-outcome account says the data were not measurable. There is no inferential result to use for judging the size, direction or precision of a blood-flow effect.
Any sample-size values presented as planning illustrations should be distinguished from observations in this study. The stated assumptions describe hypothetical planning calculations, not an analysis of measured participants and not observed power. Because the record says the observed endpoint data were not measurable, those planning calculations cannot turn the study into an estimate of an effect. The registry record does not report a sample-size justification for the study’s own design.
9. Statistical Methods Explained
What does a single-group design estimate?
In general, a single-group study collects observations from one group rather than comparing outcomes between separately assigned groups. It may describe measured values or changes within the group, if measurements are available and the analysis is specified. It does not, by itself, provide a concurrent control group against which to separate a treatment effect from other influences.
This registry record is classified as single-group, with allocation listed as NA and masking listed as none. No separate comparator is reported. The record therefore does not describe a randomized treatment contrast. The broad project aims include measurements at baseline and over time, but the primary outcome is assigned a one-visit timeframe and the record says repeat testing was not possible. The registry record does not report a completed within-person change analysis.
What would an estimate and confidence interval mean?
In general, an estimate is a numerical summary of the data, while a confidence interval describes the uncertainty associated with that estimate under the statistical method used. A narrow interval can indicate greater precision under the model; a wide interval indicates that a range of values remains compatible with the data and method. A confidence interval does not correct for a poorly defined measurement, missing observations or a design that does not address the question of interest.
No numerical primary-outcome estimate or confidence interval is reported in the registry record. The outcome description says the tested data were not measurable. Without an interpretable endpoint value, there is no reported estimate around which to assess precision. The absence of an interval is not an interval centered on no effect; it means the record does not report a quantifiable result.
Why do measurement and missingness matter?
In general, missing outcome data and unmeasurable outcome data require careful distinction from observed values. A recorded measurement represents an observation on the endpoint scale. An unavailable measurement does not have an endpoint value and should not be coded as zero unless the endpoint definition explicitly makes zero the correct value. Treating an unavailable result as zero can distort summaries and comparisons.
The registry account identifies a specific obstacle: one subject was tested, the data were not measurable, and repeat testing was not possible because the device was returned. The record does not report a method for handling missing or unmeasurable endpoint data. It also does not report whether any alternative measurement or analysis was used. The primary outcome therefore has no analyzable result in the posted record.
What can a p-value establish?
In general, a p-value measures how incompatible the observed data are with a specified null model, under the assumptions of the test. It does not measure the probability that the null hypothesis is true, and it does not show whether an effect is clinically important. Interpretation depends on the outcome, design, analysis plan and data quality.
No p-value or inferential analysis is reported in the registry record, and the analysis count is recorded as 0. In the absence of a measurable endpoint result, a p-value would not supply the missing blood-flow measurement. The registry record does not report a planned test, a null hypothesis or an analysis model.
How should planning calculations be read?
In general, a sample-size calculation asks how many participants or events might be needed under stated assumptions to detect a specified effect with a chosen error rate and power. Its output depends on the assumed effect, outcome variability, design, allocation and analysis. Changing those assumptions can change the planning result. A planning calculation is not a result observed in the trial.
The record’s planning assumptions describe a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. Time-to-event planning is described as total events, while other planning is described as participants per arm. These are planning assumptions, not the registered study design: the study is listed as single-group and no comparator is reported. The record says the blood-flow data were not measurable, so a planning calculation based on an observed effect cannot be read as a measured effect from this study. Any such figures are illustrations, not observed power. The registry record does not report the study’s own sample-size justification.
Why does over-dispersion matter in general?
For outcomes analyzed with count models, over-dispersion means the observed variability exceeds what a simple model assumes. If it is ignored, standard errors can be too small and intervals or tests can appear more precise than warranted. Analysts may use a model that accounts for extra variability, but the choice depends on the outcome and design. This is a general statistical consideration; the registry record does not report a count outcome, a dispersion estimate or an analysis model for the primary endpoint.
What is the role of an analysis plan?
In general, a prespecified analysis plan helps define which outcomes, comparisons and statistical methods will be used, reducing ambiguity after results are known. It can specify how repeated measures, missing data, multiplicity and deviations from planned procedures will be handled. The registry record does not report a statistical analysis plan or methods for these issues. That absence means the intended analytic decisions cannot be reconstructed from the registry record; they should not be guessed from the study’s broad aims.
10. Multiplicity, Missing Data and Analysis Populations
Multiplicity arises when several outcomes, comparisons, time points or subgroups are analyzed. In general, testing many hypotheses can increase the chance of at least one apparently notable result by chance. Prespecified priorities and appropriate adjustment or interpretation strategies can help address that issue. The registry record identifies one primary outcome measure, “Imaging Blood Flow,” but it does not report a multiplicity strategy or a detailed list of secondary analyses. Such a strategy is not reported in the registry record.
The primary-outcome description says that one subject was tested, the data were not measurable, and repeat testing was not possible after the device was returned. The record does not report an imputation method, a missing-data model, or an alternative analysis for the unavailable endpoint. The reason given for the inability to repeat testing is documented, but no statistical handling of the unmeasurable data is described. An unmeasurable outcome should not be interpreted as a zero value.
The record does not report an analysis population definition, such as rules for including participants in a particular analysis. It lists one subject tested in the primary-outcome description and enrollment of 1, but does not describe a broader analysis population or a protocol for departures from planned testing. The analysis count is recorded as 0, and no primary-outcome estimate or inferential result is reported.
These omissions limit reconstruction of the intended analysis. They do not imply that a particular method was or was not used outside what the registry record reports. The available registry entries support a narrow conclusion: no analyzable primary blood-flow result is reported, and methods for multiplicity, missing outcomes and analysis populations 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 |
|---|---|---|---|
| Clinic Subjects | 0 | 1 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Clinic Subjects | 0 of 1 |
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 |
|---|---|
| Clinic Subjects | 0 of 1 |
The adverse-event figures list the “Clinic Subjects” group with 1 at risk for serious adverse events and 0 affected. The record also lists 1 at risk for other adverse events and 0 affected, with 0 deaths. These are the posted counts; they should be read as counts within the recorded group, not as estimates of the frequency of events in a broader population.
In general, a count of zero observed events in a small group does not establish that an event cannot occur. It also does not provide a precise estimate of risk. Interpretation depends on the number observed, the period and completeness of safety follow-up, and how events were collected and classified. The registry record does not report the duration or detailed methods of safety surveillance.
The group is recorded as having 1 at risk, and the primary-outcome description says one subject was tested. The available safety counts do not change the fact that the primary blood-flow data were not measurable. No serious adverse-event terms are listed. The posted figures are descriptive safety counts; they should not be treated as evidence of comparative safety, since no separate comparator is reported.
12. What the Result Does, and Does Not, Mean
The record describes an attempt to use laser speckle flowgraphy to image regional skin blood flow. The broad project aim includes assessing normal and abnormal flow and examining changes over time in relation to treatment or environmental conditions. The registered primary outcome is “Imaging Blood Flow,” with a one-visit timeframe.
What the posted results do establish is limited. Enrollment is recorded as 1, and the outcome description says one subject was tested. It further states that the data were not measurable, the device had to be returned after the company went out of business, and repeat testing was not possible. The registry record therefore does not provide a numerical result for blood flow.
This does not show that blood flow was unchanged, that imaging failed under all circumstances, or that the device could not measure flow in other settings. Those conclusions would require analyzable data and an appropriate design. The record also does not report an estimate of measurement reliability, a comparison with another method, or results by body region or clinical condition. These details are not reported in the registry record.
The single-group design and absence of a reported comparator mean the record does not support a like-for-like treatment comparison. The planned ideas of observing changes over time or in response to environmental changes do not substitute for completed measurements. Nor can the listed conditions be treated as evidence that each condition was represented in analyzed data.
Statistically, the central finding is the lack of an interpretable primary endpoint result. There is no reported effect estimate, interval or inferential analysis from which to judge magnitude or precision. The planning assumptions do not fill this gap: planning illustrations are not observed results or observed power. The record is informative about the study’s intended measurement and why repeat testing was not possible, but it does not answer whether regional skin blood flow changed or how accurately the device measured it.
13. Why This Trial Matters Statistically
This record is statistically important because it illustrates the difference between a study’s scientific aim and an analyzable result. The project aimed to quantify regional skin blood flow, including possible changes over time and in response to treatment or environmental conditions. But the primary-outcome account says the data from the tested subject were not measurable and repeat testing could not be performed. A clearly stated aim does not yield an estimate when the endpoint cannot be interpreted.
It also shows why measurement feasibility is part of statistical evidence. Statistical summaries, confidence intervals and tests all depend on usable observations. When the intended measurement is unavailable, statistical methods cannot recover the missing endpoint value without additional information and assumptions. The record does not report an alternative measurement or missing-data analysis.
The design context matters as well. A single-group study without a reported comparator can describe observations if they are available, but it does not provide a randomized group contrast. This distinction helps prevent a study aim from being mistaken for a treatment-effect estimate. The record’s termination and lack of an analyzable primary outcome further limit what can be inferred.
Finally, planning illustrations should be separated from observed evidence. A calculation based on stated assumptions is useful for exploring a future design, but it is not an effect observed in this study and cannot replace measurement. The registry record does not report the study’s own sample-size justification. The statistical lesson is straightforward: design, measurement success and transparent analysis all determine what conclusions data can support.
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 direct limitation is that the primary-outcome description reports unmeasurable data. Although one subject was tested, the record does not provide a blood-flow value that can be summarized or analyzed. Repeat testing was not possible because the device was returned after the company went out of business. This prevents estimation of the primary outcome from the posted record.
The study is listed as single-group, with allocation recorded as NA and masking as none. No separate comparator is reported, so a like-for-like group comparison is not available. The listed enrollment is 1, and the record does not provide analyzed results across regions, conditions or time points. The broad list of conditions and specialty categories should not be taken as evidence that each was assessed.
The registry record does not report the endpoint unit, a numerical parameter definition, or a dispersion measure. It also does not report a detailed analysis plan, missing-data method, analysis population definition, multiplicity strategy, or sample-size justification. These omissions prevent reconstruction of how a completed dataset would have been analyzed.
The primary outcome has a one-visit timeframe, while the project summary describes interest in measurements at baseline and over time. The record does not report successful repeated measurements or an analyzed response to treatment or environmental conditions. The termination status and stated equipment-related obstacle further constrain interpretation. Taken together, these limitations mean the record documents the intended measurement and its failure to yield usable data, rather than an estimate of skin blood flow or its change.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: LSFG-SKIN, Laser Speckle Flowgraphy — NCT03660618.
- Registry record last updated 2023-05-10; status last verified 2023-05.
- Results first posted 2023-05-10.
- 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
NCT03660618, titled “LSFG-SKIN, Laser Speckle Flowgraphy,” is recorded as a terminated, single-group study of laser speckle flowgraphy for imaging blood flow. Allocation is listed as NA, masking as none, and the phase as NA. Enrollment is recorded as 1. The recorded study dates are 2017-05-23 for start and 2019-03-02 for primary completion.
The primary outcome is “Imaging Blood Flow,” with a one-visit timeframe. The outcome description says one subject was tested, the data were not measurable, and repeat testing was not possible after the device was returned. No analyses are listed, and no analyzable primary blood-flow result is reported.
The safety record lists 0 serious adverse events, 0 other adverse events and 0 deaths in the group, with 1 at risk for each adverse-event category. The registry record does not report a comparator or a detailed statistical analysis plan.