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 User Performance of the CONTOUR NEXT and CONTOUR TV3 Blood Glucose Monitoring System (BGMS) (NCT03730480), a na na study. The primary outcome is Fingerstick Contour Next BGMS and Contour TV3 Results Compared to the Reference Analyzer.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03730480 |
| Phase | NA |
| Condition | Diabetes Mellitus |
| Allocation | Not applicable (single group) |
| Design model | Sequential |
| Masking | None (open label) |
| Enrollment | 372 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Ascensia Diabetes Care |
| Results posted | Yes |
2. Clinical Question
Population
People with and without diabetes were enrolled. The registry describes lay users and healthcare professionals contributing information about the meter systems. The study enrollment is 372.
Intervention
Participants used both the CONTOUR NEXT and CONTOUR TV3 blood glucose monitoring systems. They collected fingerstick samples at different times and in different order. A trained healthcare professional also drew an arm blood sample for testing on both systems.
Comparator
The primary accuracy assessment compared meter results with a reference analyzer. The registry explicitly says the two meter systems were not compared with each other for this endpoint. The study is not described as a randomized, like-for-like comparison between treatment arms.
Primary question
How many participants had self-collected fingerstick results from the meter systems that were within 15% of results from the reference analyzer? The registry names this as the primary outcome, with a timeframe of 1 day. It does not report the outcome count or an estimate of accuracy.
3. Trial Design
This completed device study evaluated user performance of the CONTOUR NEXT and CONTOUR TV3 blood glucose monitoring systems among people with and without diabetes. The registry records an enrollment of 372 and lists Diabetes Mellitus as the condition. The study began on 2018-09-06, and primary completion was recorded as 2018-10-31.
All participants are described as testing both systems. They used the meters at different times and in different order, with fingerstick samples collected for meter testing. The study also included an arm blood sample drawn by a trained healthcare professional and tested on both systems. Meter results were assessed against a standardized reference test system. The primary endpoint concerns agreement with that reference, not a head-to-head difference between the two meters.
The registry classifies the model as sequential, allocation as NA, and masking as none. It does not report the operational details behind the sequential classification or a randomized assignment procedure. The record states that allocation was not applicable and cautions that the arms are not a like-for-like control comparison. Thus, the study should not be read as a randomized trial comparing two separately assigned groups.
Participants completed a questionnaire about their experience using the meters and evaluating the Instructions for Use. After meter testing and the first questionnaire, study staff demonstrated selected meter features only to participants with diabetes; those participants then answered a second questionnaire. The listed secondary outcome concerns responses to eight statements about experience with both systems. The registry lists two outcome measures and one analysis, but does not provide detailed analysis procedures for these measures.
The registry lists the study status as completed and identifies Ascensia Diabetes Care as the sponsor. It does not report a phase, which is listed as NA. The study description gives the activities and endpoint but does not provide a full protocol or a detailed account of enrollment 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.
Before assignment: No pre assignment
Overall Study
| Stage | Contour Next and Contour TV3 -Subjects With and Without Diabetes |
|---|---|
| STARTED | 372 |
| COMPLETED | 371 |
| NOT COMPLETED | 1 |
Reasons for not completing this period:
| Reason | Contour Next and Contour TV3 -Subjects With and Without Diabetes |
|---|---|
| Meter displayed a HI result which is non evaluable. | 1 |
Analysis population for the primary outcome, as defined in the registry: Number of fingerstick self test results from Contour Next BGMS and Contour TV3 BGMS that are within 15% of reference analyzer results.
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 | Contour Next BGMS and Contour TV3 BGMS -Subjects With and Without Diabetes |
|---|---|---|
| Participants analysed | 372 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 295 |
| Age, Categorical: >=65 years | Participants | 76 |
| Age, Continuous: mean age | years | 53.1 (SD 14.86) |
| Sex: Female, Male: Female | Participants | 206 |
| Sex: Female, Male: Male | Participants | 166 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 49 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 323 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
6. Primary Endpoint
The registry lists the primary outcome as Fingerstick Contour Next BGMS and Contour TV3 Results Compared to the Reference Analyzer, measured over 1 day.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is a participant count: the number of participants with self-fingerstick results from the CONTOUR NEXT and CONTOUR TV3 systems that were within 15% of reference-analyzer results. Its timeframe is 1 day. The registry describes the outcome in terms of participants and specifies that the meter systems’ results will not be compared with one another.
Using a reference analyzer gives the assessment an external benchmark. The question is whether meter readings fall within the stated accuracy range relative to that benchmark. This differs from asking whether two meters produce similar readings: two devices could agree with each other without either matching the reference, or differ from each other while each is assessed against the same reference. The registry’s endpoint is designed around the latter reference-based assessment.
The count format is important for interpretation. A count alone would describe how many participants met the endpoint definition, but interpretation also depends on the denominator included in the analysis, how multiple readings per participant were handled, and how missing or unusable measurements were treated. Those details are not reported in the registry record. Nor is the primary outcome count reported, so the registry record does not establish the observed proportion meeting the criterion or the precision of that estimate.
The endpoint does not, by itself, describe questionnaire responses, usability across all possible settings, or performance beyond the described assessment. The registry lists the outcome timeframe as 1 day; broader duration or repeated-use performance is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies a clear primary measurement question: whether participants’ self-collected fingerstick results from the two blood glucose monitoring systems were within 15% of the reference-analyzer results. However, it does not report the numerical primary outcome. There is no reported count of participants meeting the criterion, denominator for that count, confidence interval, or test statistic. Consequently, the registry record does not allow the magnitude or statistical precision of the observed accuracy result to be described.
The endpoint is reference-based rather than a direct comparison between the CONTOUR NEXT and CONTOUR TV3 systems. This distinction matters. The design description says that participants used both systems, but the primary endpoint does not ask which system performed better, whether one had fewer out-of-range results, or whether the systems were equivalent. A conclusion about relative performance would require a defined comparative estimate and its uncertainty, neither of which is reported in the registry record.
The record describes 372 participants enrolled, but enrollment should not be treated as the denominator for the primary result. The analyzed population and number of evaluable participants are not reported in the registry record. The enrollment figure also does not indicate how many participants had diabetes or without diabetes, nor how many had valid measurements for either meter. No subgroup results are reported.
Because the numerical outcome is absent, readers cannot assess how close the observed performance was to the 15% criterion or whether estimates were precise. In general, a confidence interval expresses the range of values compatible with the data under the analysis assumptions; no such interval is reported for this primary outcome. The absence of a reported estimate is not evidence that the meter systems met or failed the criterion. It means the registry information does not establish the observed result.
The study also collected user-experience information, including questionnaire responses and, for participants with diabetes, responses after a demonstration of selected features. The registry lists a secondary outcome concerning responses to eight statements, but numerical questionnaire findings are not reported in the registry record. Those outcomes therefore cannot be interpreted alongside the accuracy endpoint.
The adverse-event listing reports 0 serious adverse events among 372 participants at risk, 2 other adverse events among 372 at risk, and 0 deaths. These figures are descriptive safety counts in the registry entry. They do not supply detail about the events or establish comparative safety, since the record does not present a randomized control comparison.
9. Statistical Methods Explained
The registry gives an endpoint definition and broad design labels, but it does not report a complete statistical analysis plan. The explanations below describe general statistical principles that help frame the endpoint; they are not claims about analyses that the study actually performed.
What does a reference-based accuracy endpoint ask?
The primary outcome is based on whether fingerstick meter results are within 15% of a reference-analyzer result. In general, defining a tolerance relative to a reference converts a measurement comparison into a criterion that can be counted: each assessed result can be classified according to whether it meets the specified range. The registry states the resulting endpoint as a number of participants, rather than reporting a continuous measure of meter-reference difference.
That distinction affects interpretation. A participant-level count needs rules for translating measurements into a participant-level outcome. For example, a protocol must specify how to classify a participant who has multiple readings and whether all readings, a selected reading, or another summary determines the classification. The registry record does not report those rules. It also does not provide the individual readings or a summary distribution of measurement differences.
Why distinguish participants from measurements?
In general, multiple readings from one participant are not statistically independent observations: readings from the same person may be more alike than readings from different people. Treating every reading as independent can make an analysis appear more precise than it is. Participant-level analysis, or an analysis that accounts for clustering of readings within people, can address this dependence, but the registry does not say which approach was used. The endpoint wording refers to participants, while the brief study description also refers to meter samples; the analysis details that connect those units are not reported in the registry record.
The record says every participant tested both systems. This means measurements from the same participant could be related. In general, paired data can be analyzed by accounting for within-person pairing when the question is a comparison between conditions. But the primary endpoint is explicitly not a comparison of the two meter systems with each other. The record does not report a paired comparative analysis, and it would be inappropriate to infer one from the fact that people used both devices.
What does an estimate and its uncertainty contribute?
A count is most informative when accompanied by its analysis denominator and an uncertainty measure. In general, a confidence interval describes a range of values reasonably compatible with the observed data and the statistical model. A narrow interval indicates greater precision than a wide interval, though precision does not itself establish practical importance. The registry record reports neither the primary count nor a confidence interval, so the degree of uncertainty cannot be evaluated.
Likewise, a hypothesis test or p-value would address a particular statistical question only if the tested hypothesis and analysis were specified. The registry record does not report a primary-outcome p-value, a target threshold for a formal test, or the statistical model. No significance conclusion can be drawn from the endpoint definition alone. The 15% criterion is part of the outcome definition; it is not, by itself, a reported statistical test result.
What do the design labels establish?
The study is classified as sequential, with allocation listed as NA and masking listed as none. Those labels describe the registry’s design classification, but they do not supply details of the sequence, enrollment process, measurement order, or safeguards against measurement or observer effects. The brief description says meters were used at different times and in different order, but does not report how those orders were generated or controlled. The record also cautions that the arms are not a like-for-like control comparison. Thus, the design labels do not justify treating this as a randomized two-arm efficacy comparison.
General statistical interpretation depends on how participants were selected and which participants contributed to each analysis. The registry gives an enrollment figure of 372 but does not report the analysis population, evaluable sample size, participant flow, or exclusions. It also does not report a statistical plan describing model selection, covariate adjustment, or handling of repeated measures.
How should the planning illustrations be read?
The registry’s sample-size assumptions describe planning illustrations based on the observed effect, not the trial’s own design. The stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is a stated fraction of the observed effect. General sample-size calculations illustrate what a hypothetical future design might require under chosen assumptions. They are not observed trial outcomes and should not be described as observed power. The registry record does not report the values of those illustrations in the registry record for this analysis, nor a trial-specific sample-size justification.
In general, an assumed effect size and target significance level influence a planning calculation, as do allocation and the chosen statistical model. If the underlying observed effect is uncertain, planning illustrations based on it inherit that uncertainty. Such calculations do not replace a prespecified design rationale or establish that a study was adequately powered. The registry does not report a protocol-level rationale, interim analysis plan, or a detailed statistical methods document.
What can be learned from a count endpoint?
A participant count can be straightforward to communicate, but it needs context: the criterion, eligible analysis population, denominator, missing-measurement rules, and uncertainty. In general, a count with no denominator cannot be converted into an observed rate, and no rate should be inferred from enrollment alone. A count that combines results from both systems also cannot identify whether one system contributed more qualifying results unless device-specific results are reported. Those device-specific counts and the primary endpoint result are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists two outcome measures and one analysis. It names the reference-analyzer accuracy endpoint as primary and lists a secondary outcome concerning participants’ responses to eight statements about experience with the two meter systems. The registry record does not report a multiplicity strategy, such as adjustment for multiple statistical tests or a hierarchy governing interpretation of secondary outcomes. It also does not report separate numerical results for the listed questionnaire outcome.
When a study examines multiple outcomes or many statements, general statistical practice distinguishes prespecified primary questions from additional exploratory questions. Testing many hypotheses can increase the chance of a nominally notable result arising by chance. Whether that concern applies to a particular result depends on the actual analysis plan and reporting; neither a detailed plan nor questionnaire results are reported in the registry record. The existence of eight statements does not establish that eight separate statistical tests were conducted.
Missing-data handling is also not reported in the registry record. The registry does not provide participant flow, the number with usable meter readings, reasons for missing or invalid measurements, or rules for including participants in the primary analysis. Enrollment is not necessarily the same as the denominator for an outcome. No imputation method, sensitivity analysis, or missing-data assumption is described.
The analysis populations are not reported in the registry record. It is therefore unknown whether the primary outcome used all enrolled participants, only participants with complete measurements, or another defined population. Results by diabetes status are also not reported. These omissions limit assessment of selection effects, completeness, and whether any subgroup findings are consistent with the overall endpoint.
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 |
|---|---|---|---|
| Contour Next BGMS and Contour TV3 BGMS -Subjects With and Without Diabetes | 0 | 372 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Contour Next BGMS and Contour TV3 BGMS -Subjects With and Without Diabetes | 0 of 372 |
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 |
|---|---|
| Contour Next BGMS and Contour TV3 BGMS -Subjects With and Without Diabetes | 2 of 372 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Contour Next BGMS and Contour TV3 BGMS -Subjects With and Without Diabetes |
|---|---|---|
| Vasovagal Reaction | General disorders | 1 of 372 |
| Fainting | General disorders | 1 of 372 |
The registry lists one combined group titled for participants with and without diabetes. It reports 372 participants at risk for serious adverse events and 0 affected, 372 at risk for other adverse events and 2 affected, and 0 deaths. These are event-category counts as recorded in the registry, not comparative estimates between separately assigned groups.
The serious-event count should be read as a descriptive report for this study record. It does not show that the probability of a serious event is zero, nor does it establish a safety comparison with another device or a control group. General interpretation of safety counts depends on event definitions, how events were collected, observation duration, and completeness of reporting. The registry gives no detailed event descriptions or serious-event terms; those details are not reported in the registry record.
The two other adverse events are not described further in the available record, so their nature, timing, relationship to device use, and outcomes cannot be characterized. The 0 deaths figure is the recorded death count, but does not supply a broader risk estimate. No medical conclusion should be inferred from these counts alone.
12. What the Result Does, and Does Not, Mean
The study addresses whether self-collected fingerstick results from two blood glucose monitoring systems fall within 15% of results from a reference analyzer. It also collected user feedback through questionnaires. These are distinct questions: one concerns measurement agreement with a reference, while the other concerns users’ experiences and views of the meters and their Instructions for Use.
The registry record does not report the primary accuracy count, its denominator, or a measure of uncertainty. It therefore does not show the observed level or precision of accuracy. The record also does not report the numerical questionnaire findings. Without those results, the study’s named outcomes cannot be characterized as favorable, unfavorable, or inconclusive based on the posted registry information.
The endpoint is not a direct test of whether the CONTOUR NEXT system performs better than the CONTOUR TV3 system. Although participants used both, the registry explicitly states that the results of the two systems will not be compared with each other for the primary outcome. A claim of superiority, equivalence, or noninferiority between the devices would require an appropriate comparative analysis and results; those are not reported in the registry record.
The study’s described assessment is also limited to its specified measurement procedures and timeframe. It does not establish performance in all populations, settings, patterns of use, or durations. The registry does not report detailed participant characteristics, subgroup findings, or results beyond the stated endpoint and questionnaire outcome. In general, evidence from a study is interpreted in light of its population, measurement process, and analysis, and those details are not fully available in this record.
The adverse-event counts are descriptive and do not establish comparative safety. The record reports 0 serious adverse events and 0 deaths, alongside 2 other adverse events, but does not describe the latter events or provide a control comparison. These counts should not be expanded into conclusions about risks beyond the recorded study.
The most defensible conclusion is therefore about the question the study set out to address, not an unreported result: the registry documents a reference-based meter assessment and user questionnaires, but does not report numerical outcome findings needed to judge the observed accuracy or user-experience results.
13. Why This Trial Matters Statistically
This study illustrates an important distinction in device evaluation: agreement with a reference standard is not the same question as agreement between two devices. The primary outcome is defined against a reference analyzer, while the registry explicitly excludes a direct comparison between the meter systems from that endpoint. Keeping those questions separate prevents a reader from interpreting shared use of both meters as evidence of a comparative trial.
The endpoint also highlights the value of stating the analysis unit clearly. It is described as a count of participants, even though the study involves fingerstick samples and testing with both devices. General statistical interpretation depends on how readings are summarized at the participant level, how multiple observations from a person are handled, and which participants have evaluable data. Those details are not reported in the registry record. The omission makes it difficult to assess how the endpoint operationalizes the measurement process.
Reporting an endpoint definition without its observed result leaves a substantial gap. Readers need the outcome count, denominator, and uncertainty to understand both the estimated performance and its precision. Enrollment alone cannot fill that gap, because the registry does not state that every enrolled participant contributed complete data to the primary analysis.
The study also combines measurement assessment with user questionnaires. Separating those outcome domains is statistically useful: a reference-based accuracy result cannot stand in for usability feedback, and questionnaire responses cannot substitute for measurement agreement. The registry identifies both types of outcomes but does not report their numerical findings.
Finally, the safety listing shows why event counts need context. Counts without event descriptions, observation details, and a suitable comparator remain descriptive. The record gives limited safety information, while its design classification does not support treating the study as a randomized control comparison. This case underscores that clear outcome definitions are valuable, but complete reporting of analysis populations, methods, estimates, and uncertainty is essential for interpretation.
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 primary limitation of interpreting this registry entry is that the numerical primary outcome is not reported. The endpoint definition is available, but there is no reported count of participants meeting it, analysis denominator, confidence interval, or test result. Accordingly, the observed accuracy and its precision cannot be assessed from the registry record.
The record does not describe the analysis population or participant flow. Although enrollment is 372, the number contributing usable measurements is not reported. Missing-data rules, exclusions, invalid readings, and the handling of participants with multiple measurements are also not reported. These details are important for understanding whether the analyzed participants represent the enrolled group and how the participant-level endpoint was derived.
Details of the measurement protocol are limited. The description says participants used both meters at different times and in different order and that an arm blood sample was tested on both systems. The specific order-generation process, reference-analyzer procedures, quality-control details, and statistical treatment of repeated measurements are not reported in the registry record. The registry also does not describe blinding beyond listing masking as none.
The study is not presented as a randomized, like-for-like control comparison. The registry lists allocation as NA and cautions that the arms are not a like-for-like comparison. Consequently, the record does not provide a basis for interpreting the primary endpoint as a causal comparison between the two meter systems.
Participant characteristics and results by diabetes status are not reported. Questionnaire results, detailed adverse-event descriptions, and a multiplicity strategy are also not reported in the registry record. These gaps restrict interpretation of generalizability, user experience, and safety. The sample-size assumptions describe planning illustrations, not a reported trial-specific design justification or observed power.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: User Performance of the CONTOUR NEXT and CONTOUR TV3 Blood Glucose Monitoring System (BGMS) — NCT03730480.
- Registry record last updated 2022-01-18; status last verified 2022-01.
- Results first posted 2022-01-05.
- 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
NCT03730480 is a completed device study sponsored by Ascensia Diabetes Care. It enrolled 372 people with and without diabetes and evaluated user performance of the CONTOUR NEXT and CONTOUR TV3 blood glucose monitoring systems. The registry records a sequential model, allocation listed as NA, and no masking. Participants used both systems, with meter readings assessed against a reference analyzer.
The primary outcome is the number of participants whose self-fingerstick results were within 15% of reference-analyzer results, with a stated timeframe of 1 day. The endpoint is not a comparison of the two meter systems with one another. The registry also lists a questionnaire outcome about experience with both systems.
The record reports 0 serious adverse events among 372 at risk, 2 other adverse events among 372 at risk, and 0 deaths. It does not report the numerical primary outcome, denominator for that outcome, questionnaire findings, detailed analysis populations, or statistical methods sufficient to evaluate the result. Therefore, the registry describes the study question and procedures but does not provide the numerical findings needed to characterize measured accuracy or user experience.