Tetra-NIRS Clinical Study: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Tetra-NIRS Clinical Study (NCT00871975), a na phase 4 study. The primary outcome is Number of Participants With Urodynamic Detrusor Overactivity Events or Prostatic Obstruction as Detected by Tetra-NIRS Compared to Urodynamics.

2. Clinical Question

3. Trial Design

The Tetra-NIRS Clinical Study is recorded as a Phase 4, single-group, terminated study. The registry lists an enrollment of 155. All participants were recruited to the same arm and received urodynamics testing as part of routine diagnostic work-up together with the Tetra-NIRS intervention. There was no separate control arm and the allocation is listed as not applicable. Masking is recorded as none.

The study's stated purpose was to evaluate Tetra-NIRS in comparison with conventional urodynamics and to validate previous clinical study results. Its hypothesis was that Tetra-NIRS could provide data to enhance analysis alongside standard urodynamics. These are stated aims, not findings. The registry record does not report why the study was terminated, and termination status alone does not establish why it ended or what its results were.

The recorded start was 2009-04 and primary completion was 2012-02. The primary outcome timeframe is listed as 1 Year. The record lists one outcome measure and two analyses, but does not report the analysis details or their relationship to the outcome. It also does not report a protocol-level sample-size justification, a statistical analysis plan, or whether interim analyses were planned or conducted.

Because this is a single-group diagnostic evaluation, its structure differs from a randomized comparison of treatments. Participants received both the device assessment and urodynamic testing; the question concerns how the device's patterns relate to the urodynamic findings. The record therefore does not support a treatment-effect comparison between independent arms.

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.

Before assignment: There were no group assignments.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Male and female patients were included, where the urodynamics tracings were compared against the Tetra NIRS tracings.

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: Includes both male patients suffering from LUTS, and female patients suffering from OAB.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Urodynamic Detrusor Overactivity Events or Prostatic Obstruction as Detected by Tetra-NIRS Compared to Urodynamics, measured over 1 Year.

The primary outcome is the number of participants with urodynamic detrusor overactivity events or prostatic obstruction detected by Tetra-NIRS in comparison with urodynamics. It is recorded as a participant count, with a timeframe of 1 Year. For detrusor overactivity, the registry says a qualified interpreter reviewed tracings for significant pattern changes of +/-2 Hb units. For male voiding, the stated intended use interprets a downward Tetra-NIRS trend as indicating urethral obstruction and an upward trend as indicating an unobstructed urethra.

The endpoint is intended to address whether changes in the device's signal correspond to findings observed during urodynamic testing. The registry describes the NIRS output as relative changes in oxygenated and deoxygenated hemoglobin; its numerical values do not represent actual concentrations and have no unit of measure. Instead, the output is used to track changes over time through trendline analysis.

A participant count can describe how many people met an outcome definition, but by itself does not show how often the device correctly identified findings among all participants with and without those findings. The record does not report the endpoint count, the number assessed, or a diagnostic accuracy estimate. The actual comparison therefore cannot be evaluated from the reported primary outcome information alone.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The statistical question is diagnostic rather than a comparison of assigned treatments. Each participant was to undergo routine urodynamics and Tetra-NIRS assessment. In general, a diagnostic evaluation examines how a test's classifications correspond with findings from a comparator assessment. The registry describes urodynamics as the conventional test for this comparison, but does not report detailed rules for forming paired classifications or for resolving ambiguous tracings.

What does a participant count convey?

The primary outcome is expressed as a number of participants meeting the stated detection outcome. In general, a count communicates how many people satisfy a definition, but interpretation depends on the denominator and on precisely who was eligible for assessment. A count alone does not establish the proportion of relevant cases detected, because the total number assessed and the number with the comparator finding are also needed. The registry record does not report the primary count or the corresponding denominators.

The combined outcome refers to detrusor overactivity events or prostatic obstruction detected by Tetra-NIRS compared with urodynamics. These are distinct types of findings, and the registry description gives different interpretive criteria for them. The record does not report separate results for each finding, so it is not possible to tell whether they were analyzed separately, combined into one count, or both. It also does not report how repeated events within a participant were treated in the participant-level outcome.

How should diagnostic performance be understood?

In general, sensitivity describes the fraction of people with a comparator-defined finding who are identified by the test, while specificity describes the fraction without that finding who are classified as negative. Predictive values describe the probability of a comparator finding given a positive or negative test result. Agreement measures summarize how often classifications match, and may account for agreement expected by chance. These quantities answer different questions and require the underlying paired classifications. They cannot be recovered from an outcome title or from the stated study hypothesis. No such diagnostic performance estimates are reported in the registry record.

A confidence interval, in general, describes the range of estimates compatible with the observed data under a statistical model and its assumptions. It helps convey precision; a point estimate alone does not. No confidence interval or other uncertainty estimate for the primary comparison is reported. Therefore, the precision of the diagnostic findings cannot be assessed from the registry record.

Why do signal interpretation and measurement matter?

The registry states that NIRS numerical output represents relative change in hemoglobin concentrations rather than the concentrations themselves. It has no unit of measure and is interpreted through trends over time. That makes the interpretation of the signal pattern central to the outcome definition. The record describes a +/-2 Hb-unit change criterion for detrusor overactivity assessment and trend direction during male voiding, but does not report further details such as reader agreement, reproducibility, or how borderline patterns were handled.

In general, consistent and clearly defined interpretation rules help limit variation between readers and make a diagnostic result more reproducible. If judgments depend on reviewing tracings, the analysis can also be affected by whether readers know the comparator findings. Masking is listed as none, but the record does not clarify which people were unmasked to which information or how this applied to tracing interpretation. It is not possible to infer the effect of masking on the results.

What can the sample-size illustrations establish?

Planning illustrations based on an observed effect are not the trial's own design justification and are not observed power. The stated illustration assumptions use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect expressed as a fraction of the observed effect. Those assumptions do not describe this registered single-group design. Any sample-size illustrations should therefore be read as planning scenarios, not as evidence about how many participants were actually needed or the probability that the study detected an effect. The registry record does not report a protocol sample-size justification.

For diagnostic research, planning generally depends on the precision needed for the performance measures and on the expected distribution of comparator findings. The registry record does not report such a justification or the assumptions behind the study's enrollment. The enrollment of 155 is a recorded study characteristic, not proof that the study had adequate precision for its diagnostic question.

What analysis details remain unknown?

The record lists two analyses, but their methods, analysis populations, and results are not reported. It does not say whether the primary comparison used participant-level summaries, event-level summaries, or another approach. The record also does not specify how missing or uninterpretable tracings were handled. These details matter because exclusions or incomplete paired assessments can change both the analysis denominator and the interpretation of a diagnostic estimate.

Multiplicity refers, in general, to the problem of making multiple statistical tests or comparisons and the increased chance of at least one apparently notable result. The registry record does not report whether the two analyses involved multiple hypotheses, whether they were prespecified, or whether any multiplicity adjustment was planned. No correction or interpretation should be presumed. Taken together, the available information supports a description of the intended diagnostic comparison, but does not permit a reconstruction of the statistical analysis or its precision.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists two analyses and one outcome measure. It does not describe the analyses, identify their hypotheses, or state whether they were prespecified. It also does not report whether the analyses involved multiple tests or comparisons, or whether any approach to multiplicity was planned. In general, multiplicity can affect interpretation when several statistical claims are tested, but the record does not provide enough information to judge whether that issue arose in this study.

The number of participants enrolled is 155. The record does not report how many participants contributed data to the primary outcome, how many had interpretable tracings, or whether any participants were excluded from the analysis. It does not describe missing-data methods, imputation, or sensitivity analyses. Reasons for incomplete data, if any, are not reported in the registry record.

The analysis population is also not defined beyond the enrollment and shared study arm. It is not reported whether all enrolled participants were included in each analysis or whether inclusion depended on having both urodynamic and Tetra-NIRS readings. The registry does not specify how incomplete, indeterminate, or discordant assessments were treated. These omissions limit assessment of selection and missing-data effects.

Because outcome counts and analysis details are absent, there is no basis in the registry record for evaluating the impact of missing observations or multiplicity on the primary conclusion. The status of the study as terminated does not answer these questions.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

The registry reports 0 serious adverse events among 155 participants at risk in the Urodynamics + Tetra-NIRS group. It also reports 0 other adverse events among 155 participants at risk. These are the recorded event counts for the group, not estimates of comparative safety: the study has no separate control arm.

The death count is not reported in the registry record. The record also does not provide details on adverse-event definitions, collection procedures, follow-up completeness, or whether events were judged related to either procedure. A recorded count of zero means no events were entered in that category in the registry results; it does not establish that no events occurred outside the reported data or that a procedure carries no risk.

These figures should be interpreted as registry-reported counts within the stated group and at-risk denominator. They do not permit a treatment comparison or a broad safety conclusion.

12. What the Result Does, and Does Not, Mean

The registry record describes a diagnostic evaluation of Tetra-NIRS used alongside urodynamics, with the aim of comparing signal patterns and urodynamic findings. It identifies the population broadly as male and female patients and states how the device output was intended to be interpreted for detrusor overactivity and male voiding. It also records enrollment, study status, and adverse-event counts.

The record does not report the primary outcome count or a quantitative comparison of Tetra-NIRS with urodynamics. It therefore does not establish how often the device identified the specified findings, how often it missed them, or how closely its classifications agreed with urodynamic findings. No diagnostic accuracy estimate or confidence interval is reported. The stated hypothesis is not evidence that the hypothesis was supported.

The design also does not compare separate treatment groups. All participants were in one arm and received both assessments. The study is therefore relevant to a diagnostic comparison, not to estimating the effect of assigning one treatment rather than another. The registry record does not report why the study was terminated, and termination alone should not be treated as evidence for or against the device's performance.

In general, a diagnostic test result is best interpreted using paired findings, a clearly defined comparator, complete denominators, and uncertainty estimates. The record does not provide these outcome details. The reported enrollment and absence of recorded adverse events do not substitute for diagnostic results or establish the precision of the comparison.

The defensible conclusion is limited: the registry documents the study's intended diagnostic question and its single-group design, but the posted outcome information is insufficient to quantify the result. It does not support a conclusion that Tetra-NIRS is accurate or inaccurate, or that it changes clinical decisions or outcomes.

13. Why This Trial Matters Statistically

This study raises a practical statistical question about how a changing physiological signal should be compared with findings from an established diagnostic procedure. Tetra-NIRS output is described as a relative trend in hemoglobin concentrations rather than an absolute concentration measurement. Its interpretation depends on patterns over time and on specified signal changes. That makes the definition and reproducibility of the reading process important parts of the statistical question, not merely technical details.

The shared-arm design can support a paired diagnostic comparison when both assessments are available for the same participants. Such a design differs from a randomized treatment comparison: the central information is whether paired classifications agree and how often the device detects comparator-defined findings. Counts of participants, denominators, diagnostic estimates, and their uncertainty are needed to understand that performance. The registry record does not report those outcome results.

The study also illustrates why a trial's aim and hypothesis must be distinguished from its findings. The registry states that Tetra-NIRS was intended to enhance analysis alongside standard urodynamics, but does not report whether the primary comparison supported that proposition. Enrollment alone cannot resolve that question, and adverse-event counts do not measure diagnostic accuracy.

For statistical interpretation, the record's missing result and analysis details are consequential. Without an outcome count, paired classifications, and an analysis description, readers cannot assess diagnostic performance, precision, or the role of missing data. The record remains informative about the planned diagnostic setting and signal interpretation, while leaving the central empirical comparison unquantified.

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 principal trial-specific limitation in the registry record is that the primary endpoint result is not reported. The record gives the outcome definition and timeframe, but no participant count for the outcome and no quantitative comparison between Tetra-NIRS and urodynamics. Diagnostic performance and its precision therefore cannot be assessed.

The design has a single arm, with all participants receiving both urodynamics and Tetra-NIRS. This is not a randomized comparison between independent groups. Although a within-participant comparison is relevant to the stated diagnostic question, the record does not provide the paired classifications or enough analysis detail to determine how the comparison was conducted.

The participant information is limited. Male and female patients are described, and lower urinary tract symptoms and overactive bladder are listed, but further characteristics and condition-specific counts are not reported. The record does not state how many participants had evaluable paired tracings or whether the outcome was reported separately for detrusor overactivity and prostatic obstruction.

The registry does not report the statistical analysis plan, the rationale for enrollment, the analysis population, missing-data handling, or the reason for termination. It also does not give details of reader masking or agreement. These omissions restrict assessment of potential sources of bias and uncertainty; they do not, by themselves, establish that a particular bias occurred.

The safety results are limited to recorded counts, with deaths not reported in the registry record. Event definitions and collection details are also absent. These constraints mean that both diagnostic and safety interpretation must remain limited to what the registry actually reports.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Tetra-NIRS Clinical Study — NCT00871975.
• Registry record last updated 2016-07-19; status last verified 2016-06.
• Results first posted 2016-07-19.
• 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.

18. Record Summary

The Tetra-NIRS Clinical Study (NCT00871975) is recorded as a Phase 4, single-group study with an enrollment of 155 and a terminated status. All participants received urodynamics testing together with Tetra-NIRS. The stated objective was to compare Tetra-NIRS findings with conventional urodynamics; the primary outcome concerned participants with detrusor overactivity events or prostatic obstruction detected by the device compared with urodynamics.

The primary outcome timeframe is 1 Year. The registry record does not report the primary outcome result, diagnostic performance estimates, or their precision. It lists 0 serious adverse events and 0 other adverse events among 155 participants at risk; deaths are not reported in the registry record. The reason for termination and key analysis details are also not reported.