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 Feasibility Study of New Method of Diagnostic and Prediction of Painful CIPN (NCT03206216), a non-randomized na study. The primary outcome is A-delta:C Pain Threshold Ratio.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03206216 |
| Phase | NA |
| Condition | Burning Pain, Impaired Balance, Malignant Ovarian Neoplasm |
| Allocation | Non-Randomized |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 1 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Stanford University |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned patients with ovarian cancer receiving standard of care chemotherapy, in whom chemotherapy-induced peripheral neuropathy (CIPN) could be painful or painless. The registry reports an enrollment of 1. The only participant withdrew before the 21-week assessment, and no primary outcome assessment was possible.
Intervention
The diagnostic test was the Diode Laser fiber type Selective Stimulator (DLss). The study description says the test stimulates pain nerve fibers in the skin with laser light. The planned assessments were over 30 minutes at 9 and 21 weeks after the first day of standard of care chemotherapy. A questionnaire assessed pain after stimulation.
Comparator
The planned groups were participants with painful CIPN and participants with painless CIPN. This was a non-randomized, single-group study, not a randomized comparison. The group labels therefore describe clinical categories, not treatment assignments or a like-for-like control comparison.
Primary question
The primary endpoint was the A-delta:C pain threshold ratio, based on A-delta-fiber and C-fiber pain thresholds. The planned outcome was the difference in that ratio between the 9-week and 21-week assessments, reported as a mean with standard deviation separately for participants with painful and painless CIPN. The registry also lists a secondary outcome concerning correlation between the ratio and pain development. With no primary outcome assessment possible, the record cannot answer whether the ratio tracked or predicted pain development.
3. Trial Design
This was a feasibility study of a diagnostic test, rather than a randomized treatment trial. The registry describes the allocation as non-randomized, the model as single-group, and masking as none. It lists the phase as NA. These design features matter when interpreting the planned comparison: the study was not structured to estimate a randomized causal effect of one treatment relative to another.
The intervention was DLss testing. The planned schedule described a 30-minute test at 9 and 21 weeks after the first day of standard of care chemotherapy, with a questionnaire used to assess pain after stimulation. The record describes separate groups for participants with painful CIPN and painless CIPN. The outcome description intended to compare each participant’s A-delta:C pain threshold ratio between the two assessments and then report results by group.
The registry lists an enrollment of 1 and a status of terminated. The only participant withdrew before the 21-week assessment. The record says no outcome assessment was possible. It does not report why the study was terminated or why the participant withdrew. The study start date is 2017-08-04, and the primary completion date is 2017-10-30; those dates do not establish why enrollment or follow-up ended.
Because the group categories were not assigned randomly, any planned differences between them would not, by themselves, establish that the test or a clinical characteristic caused pain development. Moreover, the record contains no completed primary outcome to describe. The design and enrollment information therefore support an account of what the study intended to examine, but not an estimate of diagnostic performance or a comparison of pain trajectories.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Group A - Painful CIPN | Group B - Painless CIPN |
|---|---|---|
| STARTED | 0 | 1 |
| COMPLETED | 0 | 0 |
| NOT COMPLETED | 0 | 1 |
Reasons for not completing this period:
| Reason | Group A - Painful CIPN | Group B - Painless CIPN |
|---|---|---|
| Withdrawal by Subject | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: The only participant withdrew before the 21-week assessment. No outcome assessment is possible.
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: No participants accrued to Group A Painful CIPN prior to study termination.
| Characteristic | Unit | Group A - Painful CIPN | Group B - Painless CIPN | Total |
|---|---|---|---|---|
| Participants analysed | 0 | 1 | 1 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 0 | 0 | 0 |
| Age, Categorical: >=65 years | Participants | 0 | 1 | 1 |
| Sex: Female, Male: Female | Participants | 0 | 1 | 1 |
| Sex: Female, Male: Male | Participants | 0 | 0 | 0 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 | 0 | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 0 | 1 | 1 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): White | Participants | 0 | 1 | 1 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | participants | — | 1 | 1 |
6. Primary Endpoint
The registry lists the primary outcome as A-delta:C Pain Threshold Ratio, measured over Up to 24 weeks.
| 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 endpoint was the A-delta:C pain threshold ratio. The registry describes it as calculated from A-delta-fiber and C-fiber pain thresholds. The intended outcome was the difference in this ratio between the assessment at 9 weeks and the assessment at 21 weeks, with a mean and standard deviation reported separately for participants with painful CIPN and those with painless CIPN.
The ratio was relevant to the study’s stated question because the study aimed to explore whether laser stimulation of skin pain fibers could help predict painful CIPN, relate to neuropathy severity during and after chemotherapy, or help explain mechanisms of chemotherapy-induced neuropathic pain. The registry also lists a secondary outcome concerning correlation between the ratio and pain development. These aims describe the motivation for collecting the measure; they do not establish that the measure predicts pain or reflects severity.
For a change-based endpoint, observations at both planned assessments are needed to calculate the within-participant difference. The record states that the only participant withdrew before the 21-week assessment and that no outcome assessment was possible. Consequently, it reports no endpoint value, group mean, standard deviation, or estimated change. The endpoint is specified, but it cannot be evaluated from the posted results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central result is the absence of an assessable primary endpoint. The registry reports an enrollment of 1 and states that the only participant withdrew before the 21-week assessment. It explicitly notes that no outcome assessment was possible. Thus, the posted results do not give an A-delta:C pain threshold ratio change, a mean, a standard deviation, or a comparison between painful and painless CIPN.
This is not evidence that the ratio did or did not change, nor does it show whether the test predicted pain development. It means the planned endpoint could not be estimated from the recorded study. Without an observed endpoint, there is no effect estimate to interpret, no precision interval for that endpoint, and no basis for judging how closely the measure tracked pain development in this study.
The design further limits what a completed comparison could have established. The record describes non-randomized allocation and painful and painless CIPN groups. These are not like-for-like randomized controls. In general, non-randomized group differences may reflect factors other than the measure being studied, and a small feasibility study is not automatically a validation study. Here, those considerations are secondary to the fact that there is no primary outcome result at all.
The adverse-event record lists 0 serious events, 0 other events, and 0 deaths among the Group A participants at risk count of 0; for Group B, it lists 0 serious events, 0 other events, and 0 deaths among the participants at risk count of 1. These figures describe the registry’s safety entries. They do not supply a primary endpoint result, and the different at-risk counts do not support a comparative safety estimate.
The record lists a secondary outcome about correlation between the ratio and pain development, but it reports no analyses. The correlation result is therefore not available. No diagnostic accuracy estimates, predictive performance measures, or inferential statistics are reported. Statistical interpretation should remain bounded by that absence rather than treating the study’s aims as findings.
The study status is terminated. The reason for termination and the reason for withdrawal are not reported in the registry record. The dates and enrollment entry provide context for the record, but they do not explain the reasons for stopping or establish whether the planned schedule was completed by any participant. Overall, the posted information documents an intended feasibility investigation that yielded no evaluable primary endpoint.
9. Statistical Methods Explained
What was the planned endpoint? The primary endpoint was a change in the A-delta:C pain threshold ratio, calculated from A-delta-fiber and C-fiber pain thresholds. The outcome description specifies the difference between the 9-week and 21-week assessments and a planned summary as the mean with standard deviation for painful and painless CIPN groups. This defines the quantity the investigators intended to summarize; it is not an observed result.
Why does a change endpoint need both assessments? In general, a within-participant change compares measurements from the same person at different assessments. The later value is needed to calculate the difference. The registry states that the only participant withdrew before the 21-week assessment and that no outcome assessment was possible. It therefore gives no change value to summarize. A planned calculation cannot replace a missing observation.
What would a mean and standard deviation describe? In general, a mean describes the center of a set of measurements, while a standard deviation describes how dispersed those measurements are around that center. Both require observed endpoint values. Since the record reports no primary outcome assessment, neither summary is available for this endpoint. The registry record does not report an alternative summary or analysis for the missing endpoint.
What can a correlation answer? In general, correlation describes how two measured quantities vary together; it does not, by itself, establish that one causes or predicts the other. The registry lists a secondary outcome concerning correlation between the A-delta:C pain threshold ratio and pain development. It reports 0 analyses, and the primary endpoint could not be assessed. No correlation estimate or inferential result is reported. The intended secondary question should not be mistaken for evidence of an association.
How should the design affect interpretation? The record identifies the allocation as non-randomized and the model as single-group, with no masking. It describes groups by whether CIPN was painful or painless, rather than by randomized intervention assignment. In general, randomization can help balance measured and unmeasured characteristics between treatment groups; a non-randomized comparison does not provide that protection. Group differences, if they had been reported, would require cautious interpretation and would not alone demonstrate a causal effect. In this record, no primary group comparison is available in any case.
What does a confidence interval ordinarily add? In general, a confidence interval expresses uncertainty around an estimated quantity under the assumptions of the analysis. A narrow interval is more precise than a wide one, while an interval can remain compatible with a range of values. The registry record does not report a primary endpoint estimate or confidence interval. With no endpoint estimate, there is no reported interval from which to assess precision. This is distinct from a result showing a precise absence of change.
What does over-dispersion mean in general? For count outcomes, over-dispersion means that variability exceeds what a chosen count model expects. It can make standard errors and confidence intervals too small if the model does not account for the extra variability. This is a general statistical consideration, not a method reported for this trial. The primary outcome was a threshold ratio change, and the registry does not describe an analysis model for it.
Was a statistical analysis plan reported? The record lists 0 analyses. It does not report an inferential model, adjustment variables, a method for handling repeated measurements, or a multiplicity procedure. The endpoint description gives the planned summary form, but does not provide a full statistical analysis plan. The registry record does not report whether interim analyses were planned or conducted, or a sample-size justification.
How should planning illustrations be read? Any sample-size illustrations associated with the record are described as planning calculations based on an observed effect, with a stated significance level of 0.05, equal allocation between two arms, and a normal approximation. The record says the effect to detect is a stated fraction of the observed effect, and that time-to-event calculations would give total events while other calculations would give participants per arm. These are planning assumptions, not observed trial results or observed power. Since the primary outcome was not assessed, no trial-specific observed effect is available in the registry record to support an empirical interpretation of such planning calculations.
The methods information therefore identifies the intended measure and descriptive summary, while leaving the analysis procedures largely unspecified. Most importantly, the absence of an assessable endpoint prevents application of the planned summary to participant data.
10. Multiplicity, Missing Data and Analysis Populations
The record lists a primary endpoint and a secondary outcome concerning correlation between the A-delta:C pain threshold ratio and pain development. It reports 0 analyses. A multiplicity plan describing how to handle inference across outcomes or other analyses is not reported in the registry record. Since no inferential results are posted, there are no reported p-values or confidence intervals whose interpretation would depend on a stated multiplicity adjustment. The absence of a reported adjustment should not be treated as evidence that none was considered outside the registry record.
Missing outcome information is decisive for the primary endpoint. The record states that the only participant withdrew before the 21-week assessment and that no outcome assessment was possible. The change endpoint required the 9-week and 21-week assessments; without an assessable endpoint, the registry reports no mean or standard deviation. It does not report an imputation method, a sensitivity analysis, or a missing-data assumption. The reason for withdrawal is not reported in the registry record.
The analysis population is also not described beyond the enrollment and withdrawal information. The record does not specify an intention-to-treat, per-protocol, or other analysis population, nor does it report how participants would have been assigned to such populations. No completed primary endpoint means there is no reported population-level endpoint analysis to interpret.
These omissions are not evidence about what investigators may have planned beyond the registry. They define what a reader can assess from the posted record: the endpoint was specified, but analysis details, missing-data methods, and multiplicity handling are not reported, and no outcome analysis is available.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Group B - Painless CIPN | 0 | 1 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Group A - Painful CIPN | 0 of 0 |
| Group B - Painless CIPN | 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 |
|---|---|
| Group A - Painful CIPN | 0 of 0 |
| Group B - Painless CIPN | 0 of 1 |
The adverse-event record distinguishes serious events, other events, and deaths. For Group A - Painful CIPN, it reports 0 participants at risk for serious events and 0 at risk for other events; the corresponding affected counts are 0, and deaths are 0. For Group B - Painless CIPN, it reports 1 participant at risk for serious events and 1 at risk for other events; the affected counts are 0, and deaths are 0. No serious adverse-event terms are listed.
These entries should be read as registry counts, not as evidence of a comparative safety profile. The at-risk counts differ between the groups, and the record describes a non-randomized feasibility study with enrollment of 1. Counts from such limited exposure cannot establish that events could not occur, quantify comparative risk, or support a reliable safety comparison. The zero affected counts mean that no events are recorded in these fields, not that a broader safety question has been settled.
The record does not give further detail about event ascertainment or follow-up for adverse events. It also does not explain why the Group A at-risk count is 0. These safety entries are separate from the missing primary endpoint: they do not provide information about the A-delta:C pain threshold ratio or prediction of painful CIPN.
12. What the Result Does, and Does Not, Mean
The study’s stated aim was to examine whether DLss stimulation could help predict painful CIPN in patients with ovarian cancer receiving chemotherapy. The planned primary measure was the A-delta:C pain threshold ratio, compared between 9 and 21 weeks and summarized by painful and painless CIPN group. The registry also lists a correlation outcome related to pain development.
The posted results do not answer those questions. The registry reports an enrollment of 1, states that the participant withdrew before the 21-week assessment, and says no outcome assessment was possible. There is no observed primary endpoint, no group-specific mean or standard deviation, and no reported correlation analysis. As a result, the record does not show whether the ratio changed, whether it was associated with pain development, or whether it had predictive value.
This absence should not be recast as a finding that the test failed, had no association, or was ineffective. Nor should the study’s rationale be treated as proof that the test works. The appropriate interpretation is that the intended endpoint could not be evaluated in this record.
The non-randomized design and group definitions also matter. The painful and painless CIPN categories were not randomized treatment arms, so they were not a like-for-like control comparison. Even if group-specific results had been available, a difference would not automatically show that DLss caused or prevented pain. The record does not report diagnostic accuracy measures or a validated prediction model.
The safety entries record no serious events, other events, or deaths among the listed at-risk participants, but the limited exposure does not settle the safety profile. More broadly, the registry record documents the intended feasibility question and the reason the primary outcome is unavailable, while leaving efficacy, prediction, association, and broader safety conclusions unsupported.
13. Why This Trial Matters Statistically
This trial is statistically important as an example of the difference between a clearly stated endpoint and an estimable result. The registry identifies a biologically motivated measure, specifies the assessments at 9 and 21 weeks, and describes a group-specific summary. Yet the endpoint depends on follow-up that was not completed by the enrolled participant. Without the later assessment, the planned change cannot be calculated.
That distinction is fundamental in clinical research. A protocol can define a meaningful question, but the answer depends on collecting usable observations and reporting an analysis. When follow-up is incomplete, the missing value is not equivalent to a measured value of no change. Treating it as such would turn lack of information into a false result.
The record also illustrates why feasibility, prediction, and causal inference should be kept distinct. The study aimed to assess a diagnostic approach and its relationship to pain development. A non-randomized design may be suitable for exploratory questions, but group differences would not automatically demonstrate causation. Prediction also requires reported performance evidence, which is not available.
Finally, transparent reporting of withdrawal and endpoint availability helps readers understand why a result cannot be interpreted. The registry states that the participant withdrew before the primary assessment and that no outcome assessment was possible, while leaving the reasons for withdrawal and termination unreported. That information supports a restrained conclusion: the study established an intended method of assessment, but the posted record does not provide an evaluable primary outcome.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation is the absence of any assessable primary endpoint. The registry reports an enrollment of 1 and says the participant withdrew before the 21-week assessment. Because the primary outcome was defined as a difference between the 9-week and 21-week assessments, the record reports no result for that outcome. No mean, standard deviation, or group comparison is available.
The study status is terminated, but the reason for termination is not reported in the registry record. The reason for participant withdrawal is also not reported. The record does not establish whether the planned assessments were completed at an earlier visit, so no assumption about an observed 9-week measure is warranted.
The planned groups were participants with painful CIPN and painless CIPN, but the design was non-randomized and single-group. The registry does not report a like-for-like control comparison, and the enrollment does not support meaningful estimation of between-group variation. The study’s aims concerning prediction, severity, and mechanisms are not accompanied by reported diagnostic performance or association results.
Further limitations in interpretation arise from the analysis information. The registry reports 0 analyses and does not describe an inferential model, missing-data method, multiplicity handling, or analysis population. A sample-size justification is not reported in the registry record. The safety entries are also limited: the at-risk counts differ between groups, and no detailed event-ascertainment information is reported. Taken together, these constraints mean the posted information is descriptive of study intent and completion, not evidence about the endpoint’s performance.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Feasibility Study of New Method of Diagnostic and Prediction of Painful CIPN — NCT03206216.
- Registry record last updated 2018-12-19; status last verified 2018-12.
- Results first posted 2018-12-19.
- 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
The registry describes a terminated feasibility study of the Diode Laser fiber type Selective Stimulator for examining painful chemotherapy-induced peripheral neuropathy in patients with ovarian cancer receiving chemotherapy. The design was non-randomized, single-group, and unmasked. The planned test schedule was at 9 and 21 weeks after the first day of standard of care chemotherapy, with a questionnaire assessing pain after stimulation.
The primary endpoint was the change in the A-delta:C pain threshold ratio between assessments, summarized by painful and painless CIPN group. The registry reports an enrollment of 1 and states that the only participant withdrew before the 21-week assessment. No outcome assessment was possible, and the record reports 0 analyses. A secondary correlation outcome is listed but has no reported result.
The safety entries list no serious events, other events, or deaths. The reasons for withdrawal and termination, the statistical analysis plan, and missing-data procedures are not reported in the registry record. The posted results therefore do not provide an estimate of the primary endpoint or evidence about prediction of pain development.