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 Continuous Glucose Monitoring System (CGM)-Informed Bolus Calculator Study (NCT04320069), a na na study. The primary outcome is Percentage of Time <70 mg/dL.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04320069 |
| Phase | NA |
| Condition | Type 1 Diabetes |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 25 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Insulet Corporation |
| Results posted | Yes |
2. Clinical Question
Population
People with Type 1 Diabetes. The registry lists an enrollment of 25. It does not report further eligibility details or describe the characteristics of participants who entered the outcome analyses.
Intervention
Use of the Omnipod Horizon™ Automated Glucose Control System in Manual Mode. The study summary describes training in the Manual Mode feature and in bolus calculation using manually entered blood glucose values or a CGM-informed bolus calculator.
Comparator
The comparison is between periods of use without a connected CGM and with a connected CGM in the same study group. The arm description specifies 7 days without a connected CGM and 7 days with one. This is not a randomized comparison between separate treatment groups.
Primary question
The primary endpoint is the mean percentage of time below 70 mg/dL in the 4-hour post-bolus period, comparing Phase 2 with Phase 1. The registry frames the measure as a CGM glucose metric. It does not report the phase-specific means, their difference, a confidence interval, or a test result. Therefore, the registry record identifies the question being examined but does not establish the direction, size, or precision of the observed difference.
3. Trial Design
This completed study enrolled 25 participants with Type 1 Diabetes and evaluated a device-based approach to bolus calculation. Its registry title identifies the Omnipod Horizon™ CGM-informed Bolus Calculator. The intervention is listed as the Omnipod Horizon™ Automated Glucose Control System, and the study summary describes participants using the system in Manual Mode in an outpatient setting.
The registry describes a single-group model and lists allocation as NA and masking as NONE. The arm description says all subjects used the system without a connected CGM for 7 days and with a connected CGM for 7 days. The primary endpoint timeframe specifies a comparison of Phase 2 with Phase 1 during the 4-hour post-bolus period. These features make the primary contrast a within-group comparison across use periods, rather than a comparison of independent randomized groups. The registry does not explain the phase labels in further detail or report whether the sequence was counterbalanced.
The study began on 2020-06-09, reached primary completion on 2020-09-29, and is marked COMPLETED. The summary describes training on manual blood glucose entry and use of the CGM-informed bolus calculator. It does not report details such as the training procedure, the number of boluses observed, adherence, or participant-level exposure to the device.
The registry lists 17 outcome measures, including glucose measures such as mean glucose, time below specified glucose thresholds, time at or above specified thresholds, and time in the 70-180 mg/dL range. Mean glucose and some time-below-threshold outcomes appear more than once in the listed outcome names. The record lists no analyses. It does not report the analysis population, participant flow through the study, or the number of observations included in each endpoint analysis.
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.
Phase 1: Omnipod Horizon™ Without CGM
| Stage | Omnipod Horizon™ Automated Glucose Control System |
|---|---|
| STARTED | 25 |
| COMPLETED | 25 |
| NOT COMPLETED | 0 |
Phase 2: Omnipod Horizon™ With CGM
| Stage | Omnipod Horizon™ Automated Glucose Control System |
|---|---|
| STARTED | 25 |
| COMPLETED | 25 |
| NOT COMPLETED | 0 |
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 | Omnipod Horizon™ Automated Glucose Control System |
|---|---|---|
| Participants analysed | 25 | |
| Age, Continuous | years | 26.9 (SD 15.4) |
| Sex: Female, Male: Female | Participants | 16 |
| Sex: Female, Male: Male | Participants | 9 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 2 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 23 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 1 |
| Race (NIH/OMB): White | Participants | 24 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| BMI | kg/m^2 | 23.8 (SD 6.2) |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Time <70 mg/dL, measured over Phase 2 compared to Phase 1 (comparing the 4-hour post bolus period).
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | Percent Time in Range |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is the percentage of time below 70 mg/dL, expressed as a mean, for the 4-hour post-bolus period. It is described as a glucose metric from continuous glucose monitoring. In general, a percentage-of-time measure expresses how much of a monitoring interval falls within a defined glucose range or threshold. Here, the endpoint focuses on time below the specified threshold after a bolus, rather than on a single glucose reading.
Continuous monitoring can describe glucose patterns over an interval that occasional measurements may not capture. A post-bolus window focuses the assessment on the period after bolus delivery, when the study asks whether the glucose measure differs between the two phases. These are general reasons such endpoints are used; they do not establish that a particular result is clinically important.
The registry states that the endpoint parameter is a mean and that dispersion is to be described by a standard deviation. A mean summarizes the central level across observations, while a standard deviation describes how variable those observations are around the mean. The registry record does not report the actual phase-specific means or standard deviations, nor a between-phase estimate of the difference. It therefore gives the endpoint definition and comparison timeframe but not the result needed to quantify the observed contrast.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry establishes a planned primary comparison: mean percentage of time below 70 mg/dL in the 4-hour post-bolus period, comparing Phase 2 with Phase 1. It does not report the numerical endpoint results. In particular, the registry record does not report either phase mean, the difference between phases, a confidence interval, a p-value, or an analysis of the primary endpoint. The direction and magnitude of any observed change are therefore unknown from this record.
This absence matters for interpretation. Naming an endpoint does not show whether its value increased, decreased, or stayed similar across phases. Without an estimate of the difference and a measure of its uncertainty, readers cannot assess how precisely the study characterized the contrast. The record also does not show whether the observed difference, if any, was consistent across participants or driven by a small number of observations.
The design is a single-group comparison across periods of device use without and with a connected CGM. Such a comparison can describe changes observed in the same study group, but it does not have a separate randomized control group. In general, a within-group contrast can be influenced by factors that change over time as well as by the feature being compared. The registry does not report enough information to determine the extent to which such factors were addressed, and it does not report a statistical analysis that would clarify this issue.
The registry lists 17 outcome measures and no analyses. The number of outcomes alone does not reveal which results were tested, how tests were handled, or whether any adjustment for multiple comparisons was planned or used. Such information is not reported in the registry record. Results for secondary glucose measures are also not included in the record details, so they cannot be used to corroborate or qualify the primary endpoint.
Enrollment was 25, but this is not necessarily the number of participants contributing usable data to every endpoint. The registry does not report analysis-specific sample sizes, missing CGM data, exclusions, or the handling of incomplete periods. It is therefore not possible to judge whether the available observations represented all enrolled participants or whether missingness may have affected the estimate.
For these reasons, the statistical reading is limited to the study structure and endpoint definition. The registry supports describing what was compared, over what period, and in what study group. It does not support a claim about the direction or size of the primary result, the strength of statistical evidence, or the precision of an effect estimate. These are absences of reported outcome information, not evidence that the comparison showed no difference.
9. Statistical Methods Explained
The registry describes a continuous primary measure summarized by a mean and standard deviation. The endpoint is percentage of time below 70 mg/dL during the 4-hour post-bolus period. The stated contrast is Phase 2 compared with Phase 1. The record identifies these elements of the analysis question but does not report the actual estimates or statistical test.
What does a mean describe?
In general, a mean provides a summary of the average value across observations. For this endpoint, it would summarize the average percentage of the defined monitoring period spent below the glucose threshold. A mean is useful for describing the central level, but it does not show the distribution of individual participant values. Two groups or periods can have similar means while differing in variability or in the pattern of individual changes.
The registry names standard deviation as the measure of dispersion. In general, standard deviation describes how spread out observations are around their mean. It is not the same as a confidence interval: a standard deviation describes variability among observations, whereas a confidence interval describes uncertainty around an estimated quantity. The registry record does not report either phase's standard deviation or a confidence interval for the comparison.
Why does the comparison structure matter?
The study is listed as single group, with a period without a connected CGM and a period with a connected CGM. Because the same study group is described across the periods, a natural analysis might account for the fact that observations from the same participant are related. This is a general statistical consideration, not a claim about the analysis used in this study. The registry does not report the statistical model, whether participant-level pairing was used, or how repeated observations were handled.
In general, paired analyses can use within-participant information to compare periods, while analyses treating observations as independent may not reflect the dependence between measurements from the same person. The appropriate method depends on the data structure and analysis plan. Since the registry lists no analyses, it is not possible to determine which method was applied or whether any assumptions were checked.
The periods also occur over time. In general, temporal changes unrelated to the comparison feature can influence a before-and-after contrast. Participant familiarity, day-to-day variation, changes in behavior, and other time-varying influences are examples of general considerations, not documented events in this study. The registry record does not report whether these factors were measured, controlled, or included in an analysis.
What does a confidence interval add?
In general, a confidence interval gives a range of values compatible with the data and the method used, and communicates uncertainty around an estimate. A narrow interval indicates greater precision than a wide interval, though precision does not by itself establish importance. For a comparison of means, an interval around the estimated difference would help readers understand which sizes and directions of change remain compatible with the data. No such interval is reported in the registry record, so precision cannot be assessed.
A p-value, when reported, summarizes how compatible the data are with a specified null hypothesis under the assumptions of a statistical test. It does not measure the size or practical importance of a difference. The registry record does not report a p-value for the primary endpoint. Thus, statistical significance cannot be evaluated from this record, and the absence of a reported p-value should not be interpreted as a nonsignificant result.
Why can over-dispersion matter?
In general, over-dispersion occurs when observed variability is greater than a statistical model expects. If variability is underestimated, standard errors may be too small and confidence intervals too narrow. The primary endpoint is a continuous percentage measure, and its distribution can depend on the data and how observations are collected. The registry does not report a model, distributional checks, or evidence of over-dispersion; no conclusion about those features can be made for this study. This general issue is distinct from the standard deviation, which is simply the stated descriptive measure of spread.
How should planning illustrations be read?
In general, sample-size calculations estimate how many participants would be needed under specified assumptions to detect a defined effect with a chosen significance level and power. They are planning illustrations, not observed results and not evidence that a trial had a particular probability of finding an effect. The stated planning approach uses a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a fraction of the observed effect. The record does not report the study's own sample-size justification. Because this study is described as single group, assumptions about equal allocation between two arms do not describe its actual study design; any such calculation should be understood only in the context of the stated planning illustration.
Time-to-event calculations are not relevant to interpreting the stated continuous primary endpoint. In general, different outcome types require different calculation approaches, and assumptions should match both the design and the measure. No sample-size justification or analysis plan is reported in the registry record. Consequently, the enrollment of 25 should be treated as the reported enrollment, not as proof that the study was adequately powered for the primary comparison.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 17 outcome measures, including multiple glucose measures. A collection of endpoints raises a general issue of multiplicity: when many outcomes or tests are examined, the chance of at least one apparently unusual result can increase if no adjustment or prespecified hierarchy is used. Whether that concern applies in a particular way depends on the analysis plan, which is not reported in the registry record. The registry also lists no analyses, so it does not identify which outcomes were analyzed, which tests were used, or whether multiplicity was addressed.
The record does not report missing-data counts, reasons for missing CGM observations, rules for excluding incomplete monitoring periods, or methods for handling missing values. These details matter because a mean based on incomplete data can differ from the intended estimate, especially if missingness is related to glucose patterns or participant experience. This is a general concern, not evidence that missing data occurred or affected this study.
The registry reports enrollment of 25 but does not report the number analyzed for the primary endpoint or for each secondary outcome. Enrollment and analysis population are not interchangeable: participants may contribute different amounts of usable data, and records may use endpoint-specific populations. No intention-to-treat, per-protocol, or other analysis population is specified. The registry also does not report whether all enrolled participants completed both use periods. These gaps limit assessment of selection, attrition, and the completeness of the endpoint summaries.
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 |
|---|---|---|---|
| Single | 1 | 25 | 4.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Single | 0 of 25 |
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 |
|---|---|
| Single | 0 of 25 |
Most frequent serious adverse event terms
| Event term | Organ system | Single |
|---|---|---|
| Pyelonephritis | Renal and urinary disorders | 1 of 25 |
Serious events with the highest arm-level rate: pyelonephritis (4.0%).
The registry's serious-adverse-event figures list 25 at risk and 1 affected in the group titled Single. The other-adverse-event figures list 25 at risk and 0 affected; deaths are listed as 0. The most frequently listed serious term is Pyelonephritis, reported as 4.0%. These figures describe the registry entries; they do not establish a causal relationship between an event and the device or study procedures.
In general, an at-risk count is the number of participants in the group for whom the registry reports event surveillance, while an affected count indicates how many were recorded with an event in that category. Counts of affected participants are not necessarily counts of all event episodes, because a participant can potentially have more than one event. The registry record does not provide event-level timing, duration, severity details beyond the serious classification, or an assessment of relatedness. The term-level entry should therefore be read as a description of a reported event category, not as a complete account of clinical context.
The enrollment count and safety at-risk count are both 25, but the record does not provide further participant-level reconciliation or additional safety analysis. The absence of reported other adverse events in this entry should not be interpreted as proof that no events occurred outside the registry's reporting categories or observation period.
12. What the Result Does, and Does Not, Mean
The study addresses a focused statistical question: whether the mean percentage of time below 70 mg/dL in the 4-hour post-bolus period differed between Phase 2 and Phase 1 during use of the Omnipod Horizon™ system in Manual Mode. It examines periods without and with a connected CGM in one study group. This setup can describe a within-group contrast under the study conditions.
The registry record does not report the primary endpoint values or an estimate of the phase difference. As a result, it does not show whether the measure was higher or lower in either phase, how large any change was, or how precisely it was estimated. The endpoint's name and the trial's completion status do not substitute for numerical results. Nor does a missing result indicate that the measured values were identical.
The single-group period comparison is not a randomized comparison against a separate control group. In general, observed changes across periods can reflect the feature under study, temporal variation, or other influences. Without a reported analysis plan and results, it is not possible to determine how those possibilities were considered. The registry also does not report missing-data handling, participant-level results, or the number analyzed for the primary endpoint.
The registry lists several secondary glucose outcomes and safety information, but those entries do not supply the missing primary estimate. The adverse-event counts are descriptive and do not establish causality. No conclusion about the clinical importance of the primary comparison can be drawn without the numerical endpoint results and relevant context.
Accordingly, the record supports a description of the population, intervention, period structure, primary measure, and listed safety counts. It does not support a conclusion that the CGM-informed approach improved or worsened the endpoint, nor does it establish absence of an effect. Those conclusions require reported outcome estimates and an account of their uncertainty and analysis.
13. Why This Trial Matters Statistically
This study is statistically interesting because it poses a within-group question about a continuous glucose measure during a defined post-bolus interval. Such an endpoint can represent a pattern over time rather than an isolated measurement. Comparing periods with and without a connected CGM also highlights the importance of specifying when measurements were collected and what conditions define each phase.
The design makes the relationship between observations important. When measurements come from the same participant across periods, they are generally not independent. A statistical analysis can account for this structure, but the registry does not report which approach was used. The study is therefore a useful example of why a result cannot be interpreted from endpoint labels alone: design, data structure, analysis, and uncertainty all contribute to its meaning.
The registry's outcome list also raises questions about multiplicity and reporting completeness. Several glucose outcomes are listed, but the record does not describe a testing hierarchy or adjustments for multiple comparisons, and it lists no analyses. Readers need that context to distinguish a primary confirmatory question from additional descriptive or exploratory outcomes.
Finally, the record illustrates the difference between a completed study and a fully interpretable statistical result. Completion status, enrollment, and a clearly defined primary endpoint describe important aspects of a trial, but they do not provide an effect estimate. With no phase-specific primary values or uncertainty measure reported, readers cannot evaluate the magnitude or precision of the comparison. That distinction matters when deciding what evidence a registry entry can and cannot support.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation for interpreting this study from the registry is the absence of reported primary outcome results. The registry record defines the primary measure and comparison timeframe, but does not report phase-specific means, standard deviations, an estimated difference, a confidence interval, or a p-value. It also lists no analyses. As a result, the primary contrast cannot be quantified or assessed for precision.
The record describes a single-group comparison across periods without and with a connected CGM, rather than a randomized parallel-group control. This structure limits causal interpretation in general because changes across periods may have explanations other than the feature being compared. The registry does not report whether period effects, participant-level dependence, or other sources of temporal variation were addressed.
The registry does not report participant characteristics, detailed eligibility criteria, adherence, endpoint-specific sample sizes, participant flow, or the handling of incomplete monitoring data. It is therefore not possible to assess representativeness, completeness of follow-up, or whether all enrolled participants contributed to the primary analysis. The record also does not report a statistical analysis plan, sample-size justification, multiplicity strategy, or analysis populations.
The secondary outcome list includes repeated names, and no analysis results are reported in the registry record described for this record. Safety information is limited to the listed event counts and term entry, without detailed timing or relatedness. These limitations do not demonstrate that the study had a particular result; they restrict what can be concluded from the registry information.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Continuous Glucose Monitoring System (CGM)-Informed Bolus Calculator Study — NCT04320069.
- Registry record last updated 2023-11-13; status last verified 2023-11.
- Results first posted 2023-11-13.
- 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
NCT04320069 is a completed, single-group study of the Omnipod Horizon™ Automated Glucose Control System in Manual Mode among participants with Type 1 Diabetes. Enrollment was 25. The arm description specifies 7 days without a connected CGM and 7 days with a connected CGM. The primary endpoint is mean percentage of time below 70 mg/dL during the 4-hour post-bolus period, comparing Phase 2 with Phase 1.
The registry lists 17 outcome measures and no analyses. It does not report the primary endpoint results, analysis population, missing-data approach, or statistical plan. Safety entries list 1 serious-event-affected participant among 25 at risk, 0 affected by other adverse events among 25 at risk, 0 deaths, and Pyelonephritis at 4.0% among the top serious terms. The record supports describing the design and endpoint, but not estimating the size, direction, or precision of the primary comparison.