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 SpO2 Validation of Noninvasive Red Diamond Disposable Pulse Oximeter Sensor (NCT03124602), a na na study. The primary outcome is Accuracy of Red Diamond Disposable Pulse Oximeter Sensor by Arms Calculation.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03124602 |
| Phase | NA |
| Condition | Healthy |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 35 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Masimo Corporation |
| Results posted | Yes |
2. Clinical Question
Population
Healthy volunteers; enrollment was 35.
Intervention
Each subject received the Red Diamond Disposable Pulse Oximeter Sensor.
Comparator
Sensor readings were to be compared with oxygen-saturation measurements from a laboratory blood gas analyzer.
Primary question
How accurately did the sensor measure oxygen saturation, as assessed by the ARMS error?
The clinical question concerns measurement accuracy, not whether one treatment improves a health outcome relative to another. The study description says oxygen levels would be reduced in a controlled manner by changing the oxygen concentration the volunteer breathed. During that procedure, noninvasive readings from the sensor were to be compared with measurements from a laboratory reference instrument. The stated primary measure, ARMS error, combines the average difference between the two methods with the variability of those differences.
All subjects were assigned to one test group and received the sensor. The registry record therefore describes a single-group measurement study, not a randomized comparison between separate treatment arms. The laboratory instrument is the measurement reference, rather than a control treatment given to another group. The record identifies healthy volunteers as the study population; other eligibility details are not reported in the registry record.
The registry record names the accuracy endpoint and explains how it was to be calculated, but the resulting ARMS value is not reported in the registry record. Consequently, the posted record does not state the observed degree of agreement between sensor and laboratory readings, or the precision with which that agreement was estimated.
3. Trial Design
This was a completed, single-group device study sponsored by Masimo Corporation. The registry record lists enrollment of 35 and identifies the condition as Healthy. All subjects were enrolled into the test group and received the Red Diamond Disposable Pulse Oximeter Sensor. Allocation is listed as NA, masking as NONE, and the model as SINGLE GROUP. The record does not describe a randomized assignment or a separate control group.
The study description states that oxygen levels would be lowered in a controlled manner by reducing the oxygen concentration breathed by the volunteer. The sensor's noninvasive oxygen-saturation measurements were to be assessed against measurements from a laboratory blood gas analyzer. The primary outcome description refers to a laboratory pulse Co-Oximeter as the source of the reference saturation measurement. Further procedural detail about how measurements were scheduled or paired is not reported in the registry record.
The registry dates are 2017-03-07 for study start and 2017-05-11 for primary completion. The study is marked COMPLETED. The primary measurement timeframe is described as 1-5 hours per subject. The record lists one outcome measure and zero analyses. Although the design description gives the intended measurement approach, it does not report the resulting ARMS value or other statistical results for that endpoint.
Because this is a one-group study, comparisons between treatment arms do not apply. Its central comparison is between two methods of measuring oxygen saturation in the same study context: the noninvasive device and a laboratory reference. The registry record does not report the sample-size justification, detailed protocol, analysis populations, or a prespecified statistical plan. Those omissions limit what can be inferred about the intended precision, handling of repeated readings, and analysis procedures.
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 | Noninvasive Red Diamond Disposable Pulse Oximeter Sensor |
|---|---|
| STARTED | 35 |
| COMPLETED | 25 |
| NOT COMPLETED | 10 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Red Diamond Disposable Pulse Oximeter Sensor: Noninvasive Puls |
|---|---|---|
| Participants analysed | 25 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 25 |
| Age, Categorical: >=65 years | Participants | 0 |
| Sex: Female, Male: Female | Participants | 12 |
| Sex: Female, Male: Male | Participants | 13 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 8 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 17 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
6. Primary Endpoint
The registry lists the primary outcome as Accuracy of Red Diamond Disposable Pulse Oximeter Sensor by Arms Calculation, measured over 1-5 hours per subject.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percent of oxygen saturated hemoglobin |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is titled “Accuracy of Red Diamond Disposable Pulse Oximeter Sensor by Arms Calculation.” Its stated unit is percent of oxygen saturated hemoglobin, and the timeframe is 1-5 hours per subject. The endpoint is intended to quantify how closely the noninvasive sensor readings correspond to readings from a laboratory reference instrument.
The registry describes the ARMS calculation using paired differences: the laboratory oxygen-saturation measurement is subtracted from the pulse oximeter measurement for a number of samples. The average difference is called bias, and the standard deviation of the differences is called precision. The square root of the sum of the squared bias and squared precision is the ARMS error. This combines systematic offset and variability into one accuracy summary.
General statistical context: an error summary can be useful because an instrument may differ consistently from a reference, vary from reading to reading, or show both patterns. A single combined measure gives a compact description of those two features, but it does not by itself show the full distribution of errors or how performance varies across the measurement range. The record does not report the observed bias, precision, ARMS value, or uncertainty interval. The endpoint's result is therefore not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the intended accuracy question and the calculation used to address it, but it does not give a numerical result for the primary endpoint. There is no posted ARMS value, bias estimate, precision estimate, confidence interval, or test result for the sensor accuracy outcome. No conclusion about the observed agreement between the sensor and the laboratory reference can be drawn from the endpoint description alone.
The study is marked completed and reports enrollment of 35. Completion and enrollment describe study conduct; they do not reveal the size or precision of the measurement error. The record lists one outcome measure and zero analyses. This means the record contains no reported analysis result for the primary outcome, rather than evidence that the endpoint was measured with a particular level of accuracy.
The single-group design is appropriate to describing a measurement comparison, but it does not create a randomized treatment contrast. The reference instrument serves as a comparator for readings, while all subjects received the same sensor. Therefore, the record cannot be read as a comparison of clinical benefit or harm between two interventions. It also does not report a separate control group against which changes over time could be contrasted.
General statistical context: bias describes average directional difference, while precision describes the spread of paired differences. A combined error measure can conceal whether an overall value reflects a small average offset with substantial variability, or a larger offset with less variability. The registry's explanation says both components were intended to contribute to ARMS, but their observed values are not reported. Without those component estimates, readers cannot distinguish these patterns.
Likewise, without a confidence interval or other uncertainty estimate, the record does not show how precisely the accuracy measure was estimated. The number of enrolled subjects alone cannot establish that precision: it does not specify how many usable paired readings contributed, how readings were distributed across oxygen-saturation levels, or how within-subject dependence was handled. Those details are not reported in the registry record.
The primary outcome is described as a calculation from multiple samples, but the record does not state the number of samples, the analysis population, or the method for accounting for repeated observations from the same volunteer. The numerical outcome and its uncertainty are both needed to assess the reported accuracy quantitatively; neither is available in the registry record. Interpretation should therefore remain limited to the study's stated aim and measurement method.
The registry record also does not report a protocol-based acceptance threshold or a prespecified criterion for judging the ARMS result. Without such a criterion and the actual result, the record does not establish whether the observed accuracy met any intended performance target. The planned sample-size illustrations elsewhere are not observed power and cannot substitute for the missing outcome estimate.
9. Statistical Methods Explained
The primary measurement is described through paired readings from the test sensor and a laboratory reference. The registry specifies that the reference oxygen-saturation value is subtracted from the sensor value for a number of samples. Each paired difference therefore represents the signed discrepancy between those two measurements under the study conditions. The record does not report the individual readings or the resulting differences.
What do bias and precision describe?
The mean of the paired differences is called bias in the registry description. In general statistical terms, a nonzero average difference indicates that one method tends to read higher or lower than the other, according to the subtraction order. The standard deviation of the differences is called precision in the record. In general, it describes how much individual differences vary around their average; it is not the same as the uncertainty of the average difference. The observed bias and precision are not reported in the registry record.
How does ARMS combine them?
The registry defines the ARMS error as the square root of the sum of the squares of bias and precision. In general, squaring before combining prevents positive and negative components from canceling. The result reflects both average offset and variation among paired differences. It is a summary measure, not a description of every reading, and it does not indicate on its own whether errors are larger in a particular part of the measurement range. No ARMS estimate is reported in the registry record.
The endpoint is expressed in percent of oxygen saturated hemoglobin. Its timeframe is 1-5 hours per subject. The description says the oxygen concentration breathed by volunteers would be reduced in a controlled manner, allowing the sensor to be assessed while oxygen levels changed. The registry does not provide a detailed schedule of measurements, the exact range of observed values, or the number of paired samples collected.
Why does the reference method matter?
General statistical context: assessing a measurement device requires a reference against which its readings can be compared. The registry describes comparison with oxygen-saturation measurements from a laboratory blood gas analyzer, and the endpoint description refers to a laboratory pulse Co-Oximeter. The record does not provide further technical detail on the reference procedure or explain whether these terms refer to the same specific measurement arrangement. The reference is not a second treatment arm; it supplies the comparison measurements used in the accuracy calculation.
Agreement analysis is different from testing whether two group averages differ. General context: two methods could have similar averages while individual paired readings vary considerably, or could show a consistent offset despite little variation. The ARMS formula described in the registry incorporates average difference and spread, but a single combined summary does not display their separate contributions. Separate bias and precision estimates, individual differences, or an uncertainty interval would add information, but those results are not reported in the registry record.
What can a confidence interval add?
General statistical context: a confidence interval expresses uncertainty around an estimated quantity under the assumptions of the analysis. It helps distinguish a point estimate from the range of values compatible with the data and method. The registry record does not report a confidence interval for ARMS, bias, or precision. It also does not report a hypothesis test or p-value for the primary measurement outcome. A missing interval is not evidence that uncertainty is small; it means the record does not provide that estimate.
Repeated observations from one person are generally not independent in the same way as measurements from different people. General statistical context: when multiple readings per subject are analyzed, the method may need to account for within-subject correlation, depending on the estimand and analysis. The registry says the calculation uses a number of samples but does not state how many samples each subject contributed or how repeated readings were incorporated. The statistical analysis plan and further modeling details are not reported in the registry record.
The sample-size assumptions associated with planning illustrations are two-sided significance level 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 are planning assumptions, not the registry's reported design justification; the sample-size justification is not reported in the registry record. Since this study is single-group, an equal-allocation two-arm illustration does not describe its observed design. Any displayed sample-size values are planning illustrations, not observed power, and should not be treated as an analysis of the 35 enrolled subjects.
The record lists one outcome measure and zero analyses. The named endpoint and its method therefore describe what was intended to be measured, not a posted result. The statistical plan, missing-reading rules, analysis population, handling of outliers, and any prespecified performance criterion are not reported in the registry record. These omissions prevent a fuller assessment of how the planned ARMS calculation was implemented.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists one outcome measure and zero analyses. It names a primary accuracy outcome but does not report a statistical analysis result. The record does not describe a broader set of outcomes or hypotheses, nor does it state whether any multiplicity procedure was planned. The multiplicity strategy is not reported in the registry record.
General statistical context: multiplicity can arise when several outcomes, subgroups, time points, or statistical tests are examined. Repeated testing can increase the chance of findings that appear notable by chance, depending on the testing plan. A registry entry naming one outcome does not establish that only one analysis was conducted; in this record, the number of analyses is listed as zero, and further analysis details are not reported. It is not possible to assess adjustment or selective reporting from the stated information.
The registry record does not describe missing-data handling, exclusions, or the number of participants with usable paired measurements. Although enrollment is 35 and all subjects were assigned to the test group, these registry entries do not establish that every participant contributed measurements to the primary calculation. The analysis population and missing-reading rules are not reported in the registry record.
General statistical context: missing measurement pairs can matter when the availability of data relates to subject characteristics or measurement conditions. An analysis may also need to account for repeated observations within a participant. The record does not say whether incomplete pairs were excluded, imputed, or handled by another method, or how observations from the same subject were treated. No inference about these procedures should be made from the endpoint formula alone.
The protocol, prespecified analysis plan, and any interim analysis procedures are not reported in the registry record. The record also does not identify subgroups or describe how any subgroup analyses would be handled. Thus, the posted information is insufficient to assess multiplicity control, missingness assumptions, or whether the reported analysis, if any, followed a prespecified plan.
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 |
|---|---|---|---|
| Red Diamond Disposable Pulse Oximeter Sensor: Noninvasive Puls | 0 | 35 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Red Diamond Disposable Pulse Oximeter Sensor: Noninvasive Puls | 0 of 35 |
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 |
|---|---|
| Red Diamond Disposable Pulse Oximeter Sensor: Noninvasive Puls | 3 of 35 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Red Diamond Disposable Pulse Oximeter Sensor: Noninvasive Puls |
|---|---|---|
| Dizzy/Lightheaded, Vasovagal | Injury, poisoning and procedural complications | 3 of 35 |
The registry lists 35 subjects at risk in the study group, zero subjects affected by serious adverse events, three subjects affected in the other adverse events category, and zero deaths. These are the safety counts recorded for the group. The record does not provide serious-event terms, and the list of top serious terms is empty.
These counts should be read as registry safety entries, not as a comparison between treatment groups. All subjects received the same sensor, and there is no separate control arm. The record does not state the nature or severity of the other adverse events, whether they were considered related to the sensor, or how events were collected and coded. Those details are not reported in the registry record.
General statistical context: a count of affected subjects is a descriptive safety summary. It does not, by itself, establish the cause of an event or quantify comparative risk. The observation period and detailed adverse-event definitions are also not reported in the registry record. The zero serious-event count and zero deaths are the posted counts for this study group; they do not establish that the possibility of such events is absent beyond the observations recorded.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a completed, single-group study was intended to assess the Red Diamond Disposable Pulse Oximeter Sensor's oxygen-saturation accuracy against a laboratory reference in healthy volunteers. It specifies an ARMS calculation based on the average and variability of paired differences. It also records enrollment of 35, a primary measurement timeframe of 1-5 hours per subject, and zero analyses.
The posted record does not report the ARMS result, bias, precision, confidence interval, or a statistical test for the primary endpoint. As a result, it does not show how closely the sensor readings agreed with the laboratory values in the observed data, or how precisely any accuracy estimate was determined. The method description is not a substitute for the numerical result.
The study design also defines the scope of the question. Since everyone received the sensor and there was no separate randomized control group, the record describes a measurement comparison rather than a trial of competing treatments. The reference instrument supplies a benchmark for readings; it does not represent an alternative intervention. The record therefore does not estimate a treatment effect or compare clinical outcomes between arms.
General statistical context: a device's performance in a particular controlled study setting does not, by itself, establish performance in every population or circumstance. The registry identifies healthy volunteers and a controlled reduction in breathed oxygen concentration, but the observed measurement range, participant characteristics beyond health status, and other testing conditions are not reported in the registry record. The record cannot establish generalizability beyond the described study setting.
The safety entries report zero subjects affected by serious adverse events, three in the other adverse events category, and zero deaths among 35 at risk. These are descriptive counts, not causal conclusions or a comparison with another group. Taken together, the record describes the study's purpose, design, endpoint method, and safety counts, while leaving the main accuracy result unreported.
13. Why This Trial Matters Statistically
This study illustrates a statistical distinction between evaluating a measurement method and comparing treatments. The central comparison is between paired sensor and laboratory readings, not between groups assigned to different therapies. That distinction matters when interpreting what the design can estimate: the intended target is measurement accuracy summarized by ARMS, rather than a clinical treatment effect.
The registry's ARMS definition also highlights why one average difference is not enough to describe an instrument. The method combines bias, the average paired difference, with precision, the standard deviation of those differences. General statistical context: a measure that incorporates both offset and spread can summarize two different sources of error, although the combined value does not show their separate patterns. Reporting both components and their uncertainty would help readers understand the accuracy estimate in more detail.
At the same time, the record demonstrates the limits of a method description without results. It identifies a primary endpoint and explains how it was intended to be calculated, yet gives no numerical endpoint result and lists zero analyses. Without the observed value and its uncertainty, readers cannot quantify agreement or assess the precision of an estimate. Enrollment alone cannot fill that gap.
The single-group structure is another important interpretive feature. Each subject received the sensor, and the laboratory measurement served as a reference. There is no like-for-like control-arm comparison. Consequently, treatment-comparison language or claims about relative clinical effects would not match the design recorded.
The safety summary provides descriptive counts, but not event details or comparative information. More broadly, the record does not state the analysis population, missing-data handling, or how multiple readings from the same subject were handled. These are relevant to understanding a measurement analysis, particularly where a number of samples may contribute to a subject-level or pooled summary. Their absence leaves implementation details unresolved, rather than proving that any particular method was or was not used.
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 limitation for statistical interpretation is that the registry record does not report the primary ARMS result. It also omits the observed bias and precision and any uncertainty estimate. The intended endpoint can therefore be described, but the magnitude and precision of observed measurement error cannot be assessed.
The record lists enrollment of 35 but does not state how many subjects or paired readings contributed to the accuracy calculation. It does not report the analysis population, missing-reading rules, exclusions, or the number of samples per subject. These omissions leave uncertainty about the data underlying the intended summary.
The study has a single-group design in which all subjects received the sensor. Its laboratory reference is a measurement comparator, not a separate randomized control arm. This structure does not support a treatment-arm contrast. The record also does not provide a prespecified performance threshold, detailed protocol, sample-size justification, or statistical analysis plan.
The outcome description refers to a laboratory blood gas analyzer in the study summary and a laboratory pulse Co-Oximeter in the primary measure description. Additional detail clarifying the reference procedure is not reported in the registry record. The record does not provide the observed range of oxygen-saturation values or enough information about measurement timing and repeated readings to assess those features.
General statistical context: conclusions about agreement can depend on the range and distribution of measurements, the pairing procedure, and the handling of repeated observations. Those details are not reported in the registry record. The healthy-volunteer population and controlled oxygen-reduction setting define the described study context, but further population and setting details are not listed. The record therefore does not establish how results would extend beyond this study context, especially when the primary result itself is unavailable.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: SpO2 Validation of Noninvasive Red Diamond Disposable Pulse Oximeter Sensor — NCT03124602.
- Registry record last updated 2019-08-22; status last verified 2019-08.
- Results first posted 2019-08-22.
- 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 identifies NCT03124602 as a completed study of the Red Diamond Disposable Pulse Oximeter Sensor, sponsored by Masimo Corporation. It lists enrollment of 35 healthy volunteers, a single-group design, allocation as NA, and masking as NONE. All subjects were assigned to the test group and received the sensor.
The study began on 2017-03-07 and reached primary completion on 2017-05-11. The primary endpoint was an ARMS accuracy calculation comparing noninvasive oxygen-saturation readings with laboratory measurements; the timeframe was 1-5 hours per subject. The record lists one outcome measure and zero analyses. The numerical primary result is not reported in the registry record.
Safety entries list 35 at risk, zero subjects affected by serious adverse events, three affected in the other adverse events category, and zero deaths. The record does not provide details for the other adverse events or serious-event terms.