The Virtual Visit for Women With Gestational Diabetes: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Virtual Visit for Women With Gestational Diabetes (NCT02960295), a na na study. The primary outcome is Compliance With Requirements for Frequency of Glucose Measures.

2. Clinical Question

The study asks whether women with gestational diabetes can take part in a care model that combines virtual visits with self-monitoring at home. Its primary question concerns adherence to the requested frequency of blood-glucose checks, expressed as the mean number of checks per patient per day over the study timeframe. The registry describes this as a feasibility study, rather than a randomized test comparing virtual care with another care approach.

The care description says participants were trained to use glucose meters, scales, and blood-pressure monitors connected to a cellphone app. It also describes fetal well-being checks using Dopplers and kick counts, with care delivered through alternating in-office and telephone visits. These details define the approach being assessed; they do not establish how consistently each component was used or what the measured glucose-check compliance was.

Because there is no control group, the study cannot by itself estimate how the virtual-visit approach compares with another care model. The registry record also does not report a primary endpoint result. The posted information therefore allows readers to understand the feasibility question and the intended measure, but not to judge the observed level of compliance.

3. Trial Design

This is a completed, single-group study with an enrollment of 10. The registry lists the allocation as not applicable, masking as none, and the model as single group. Those features mean the record does not describe random assignment or a blinded comparison between treatment groups. The single group is identified as the Virtual Visit group.

The care model combined home monitoring with caregiver visits. Participants were to measure blood glucose four times daily, weigh themselves weekly, check blood pressure weekly, and check fetal heart rate weekly. The record also describes training in equipment use, including Bluetooth-connected devices and a cellphone app. Care was planned through alternating in-office and telephone visits. The registry does not report how much of this care each participant completed.

The study is identified as a feasibility study for women with gestational diabetes. The registry lists a start date of 2014-09, a primary completion date of 2016-09, and a completed status. These record dates describe the study timeline; they do not supply outcome results or explain how the study determined whether the approach was feasible.

The primary endpoint is a continuous measure: the mean number of glucose checks per patient per day over the stated one-year timeframe. Three secondary outcomes are named: compliance with self-weighing requirements, compliance with blood-pressure checking requirements, and glucose concentrations. The registry lists four outcome measures and four analyses overall, but does not provide further analysis details in the record.

With a single group, the study can describe measurements within participants, if those results are reported, but it has no concurrent control group for estimating a between-group effect. The registry does not report a protocol rationale for the enrollment, a sample-size justification, or additional details of the analysis plan.

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

Analysis population for the primary outcome, as defined in the registry: women with gestational diabetes

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: Pregnant women with gestational diabetes

6. Primary Endpoint

The registry lists the primary outcome as Compliance With Requirements for Frequency of Glucose Measures, measured over 1 year.

The primary endpoint is compliance with the requested frequency of glucose measurements. The registry says each patient was asked to check blood glucose four times a day: while fasting and one hour after the first bite of each meal. For each patient, the measure is defined by dividing the number of daily glucose checks actually performed by the number of days in the study. The endpoint is described in units of number of glucose checks per patient per day, and the registry specifies a mean and standard deviation.

This measure is used to describe whether the monitoring routine was followed over time. In general, a mean can summarize the typical level across participants, while a standard deviation describes how much participant-level values vary around that mean. These summaries answer different questions: the mean describes the group’s average measured frequency, whereas the standard deviation describes variation among participants. Neither one alone explains why checks were missed or whether a particular participant’s pattern changed.

The endpoint is directly connected to the feasibility question because it records actual monitoring behavior against a requested schedule. However, the registry record does not report the endpoint’s observed mean or standard deviation. It also does not report participant-level values, the amount of missing monitoring information, or additional details about the calculation beyond the stated definition. Consequently, readers can identify what the endpoint was intended to measure, but cannot assess the recorded level or spread of glucose-check compliance from this record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes the primary outcome as a continuous measure and specifies that it is summarized by a mean and standard deviation. The following explains those statistical ideas in general; it does not assert that an unreported analysis was performed.

What does the mean describe?

In general, the mean is the arithmetic average of the values included in an analysis. Here, the intended participant-level value is the number of glucose checks per day, calculated over the study days according to the endpoint description. A group mean would summarize those participant-level values. It would not show whether every participant had a similar monitoring pattern, and it could conceal meaningful differences among participants.

What does the standard deviation describe?

In general, the standard deviation describes how dispersed individual values are around their mean. A smaller standard deviation indicates values are more closely grouped; a larger one indicates greater spread. It is not the same as the standard error or a confidence interval. The standard deviation describes variation among measured values, while a confidence interval is used to express uncertainty about an estimated quantity. The registry specifies a standard deviation for the primary outcome but does not report its value.

How should the endpoint definition be read?

The registry defines each patient’s measure using the number of daily glucose checks actually performed divided by the number of days in the study. This makes the intended measure an average daily frequency rather than a simple count of all checks across the group. The requested schedule is described as four checks daily, with fasting and post-meal timing specified. That schedule is the target participants were asked to follow; it is not itself an observed result.

The record names a one-year timeframe. It does not provide further detail about the exact observation window for each participant, how partial days were handled, or how missing monitoring records were treated. Those choices can matter for interpreting an average rate, but the registry record does not report them.

What can a single-group analysis show?

In general, a single-group study can summarize outcomes observed in the enrolled participants. It does not create a contemporaneous control condition. Without a comparator, a group’s observed value cannot be interpreted as the difference that would have occurred under another care model. This is a design limitation, separate from the question of whether a group mean is calculated correctly. The registry describes a single-group model and does not report a randomized or like-for-like comparison.

The registry identifies four outcome measures and four analyses, but does not report the analysis procedures beyond the primary outcome’s mean and standard deviation. The record does not describe adjustment for baseline values, covariates, repeated measurements, or clustering of observations. These details should not be inferred from the endpoint definition alone.

What does a confidence interval add?

In general, a confidence interval gives a range of values compatible with an estimate under a specified statistical procedure. It helps readers assess precision in a way that a point estimate alone cannot. A narrow interval indicates greater precision than a wide interval, under the assumptions used to form it. The registry record does not report a confidence interval for the primary endpoint, so the precision of the outcome estimate cannot be assessed from the information.

Statistical significance testing also cannot be reconstructed from the outcome definition. The registry record does not report a primary hypothesis test, a test statistic, or a p-value for the compliance measure. A test would not solve the design limitation of having no comparison group; it would address a different statistical question.

How should planning calculations be separated from results?

In general, sample-size calculations are planning tools. They describe how many participants might be needed for a specified analysis under stated assumptions; they are not observed outcomes and are not a measure of the study’s actual power after completion. The planning framework described for this page uses a two-sided significance level of 0.05, equal allocation between two hypothetical arms, a normal approximation, and effects expressed as fractions of the observed effect. That hypothetical two-arm framework is distinct from this registry record’s single-group design. Any resulting sample-size illustrations should therefore be read as planning examples, not as the design actually used in this trial or as evidence of observed power. The registry record does not report the trial’s own sample-size justification.

The endpoint results needed to anchor an observed-effect planning illustration are not reported in the registry record. No numerical planning counts are included in the information available for this explanation. As a result, the assumptions can be described, but neither a calculated participant requirement nor a detectable effect should be inferred from them.

Finally, the registry’s label of a continuous outcome describes the form of the measure; it does not establish that a particular statistical model was appropriate or used. In general, a model should reflect the data structure and the question being asked. The registry does not report enough analysis detail to assess model choice, assumptions, or sensitivity analyses. Readers should distinguish the documented outcome definition from statistical procedures that are not described.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Virtual Visit")
n   <- c(10)
m   <- c(3.1)
sp  <- c(1.26)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Virtual Visit  10  3.100  1.260  2.199  4.001

11. Multiplicity, Missing Data and Analysis Populations

The registry lists four outcome measures and four analyses. The primary outcome concerns compliance with the frequency of glucose measurements. The named secondary outcomes concern compliance with self-weighing requirements, compliance with blood-pressure-checking requirements, and glucose concentrations. The record does not report whether these outcomes were arranged in a testing hierarchy or whether any adjustment for multiple statistical tests was planned or used.

In general, when several hypotheses are tested, the chance of finding at least one apparently notable result by chance can increase unless the testing strategy accounts for multiplicity. The relevance of that issue depends on the questions and analysis plan. Because the registry record does not describe a multiplicity procedure or provide outcome test results, readers cannot determine how multiple testing was handled. This does not establish that an adjustment was needed or that one was omitted; the approach is not reported in the registry record.

The registry record also does not report how missing outcome information was handled. For the primary measure, this matters because the stated calculation uses daily checks and the number of study days. The record does not describe whether monitoring gaps were treated as days with no checks, excluded days, or missing observations, nor does it describe any imputation procedure. No such method should be assumed.

Analysis populations are not described beyond the enrolled single group. The record does not state whether all enrolled participants were included in each analysis, how withdrawals or incomplete records were handled, or whether analysis eligibility differed by outcome. These omissions make it difficult to assess how the analysis sample might relate to the enrolled group.

In general, transparent reporting of multiplicity, missing-data handling, and analysis populations helps readers understand which observations informed each result. Here, those methods and the outcome results themselves are not reported in the registry record.

12. Safety Results

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

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry’s adverse-event figures for the Virtual Visit group report zero serious adverse events, zero other adverse events, and zero deaths. The number at risk is listed as 10 for each category. These figures should be read as the counts recorded for this group, not as a comparison with another group.

In general, observing no events in a study does not demonstrate that an event is impossible or that the risk is zero. A safety summary is limited by the number of participants observed, the period and manner of follow-up, and how events were collected and classified. The registry record does not provide further details about event definitions, collection procedures, or follow-up for adverse events. It also does not list serious-event terms.

The absence of a comparator means the posted counts cannot quantify a difference in adverse-event frequency between virtual visits and another care model. The record’s zero counts are descriptive and should not be converted into a broader safety conclusion. They also do not replace consideration of the study’s small enrollment and the limited detail reported about safety monitoring.

Accordingly, the careful reading is that no serious adverse events, other adverse events, or deaths were recorded in the listed Virtual Visit group in this registry summary. The figures do not establish that adverse events could not occur or that the approach has a particular safety profile relative to an alternative.

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

This record describes a study designed to assess the feasibility of virtual-visit care for women with gestational diabetes. It specifies a primary measure tied to the requested glucose-monitoring schedule, outlines other home-monitoring activities, and identifies the study as single group. Those details explain what the study set out to observe and the general structure in which it was conducted.

The registry record does not report the primary endpoint result. It therefore does not show the average number of glucose checks per patient per day, the variation in that measure, or how the observed monitoring frequency related to the requested schedule. The named secondary outcomes are also not accompanied by results in the information. The study’s feasibility aim cannot be treated as a reported finding: an aim is not an outcome.

The single-group design also sets a boundary on interpretation. In general, without a comparator, it is not possible to estimate how the outcome would differ under another care model using this study alone. An observed result, even if available, would describe this enrolled group and would not establish that the virtual-visit approach caused a particular level of monitoring or any change in glucose concentrations.

The adverse-event summary records zero events in the listed categories, including zero deaths, among the 10 participants at risk. These counts describe the registry entry; they do not establish that the risk of an event is absent or compare safety with another approach.

The record can therefore support a description of the planned care model, the participant group, the endpoint definition, and the reported adverse-event counts. It cannot support a quantitative conclusion about compliance, secondary outcomes, comparative effectiveness, or comparative safety. Important information about missing data, analysis populations, and statistical methods is also not reported in the registry record.

14. Why This Trial Matters Statistically

This study is statistically useful to examine because its main measure translates a practical care task into a participant-level quantity: average glucose checks per day. That makes the intended outcome easy to connect to the monitoring schedule and highlights how a behavioral process can be summarized as a continuous measure. The registry also specifies that the mean and standard deviation were the intended summaries, which distinguishes the average level from variability across participants.

The record illustrates why study design and outcome definition need to be read together. A clearly stated measure does not create a comparison group. Because this is a single-group study, the central statistical task is descriptive within the Virtual Visit group, rather than a randomized estimate of a difference between care strategies. This distinction helps prevent readers from interpreting the study as a controlled trial when the registry does not describe one.

It also illustrates the importance of complete results reporting. The registry provides a detailed definition of the primary endpoint and lists secondary outcomes, but the observed values are not reported. Without results, readers cannot evaluate the level or spread of glucose-check compliance. Without reported analysis details, they also cannot judge how missing monitoring records or multiple outcomes were handled.

The study’s small enrollment makes transparent reporting especially relevant. In general, individual observations can have a substantial influence on descriptive summaries in a small group, so participant-level context and uncertainty can help readers understand how stable a result may be. The registry does not report the primary estimate or its uncertainty, so this assessment cannot be made from the record.

Finally, the planning assumptions described for sample-size illustrations should not be mistaken for the trial’s actual design. They use a hypothetical two-arm framework, whereas the registry describes a single group. Keeping those roles distinct is important: planning calculations do not substitute for observed results, and they do not turn a feasibility study into a comparative trial.

15. 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 most immediate limitation for interpreting this registry entry is that the primary endpoint’s observed mean and standard deviation are not reported. The endpoint definition is available, but its measured result is not. The named secondary outcomes likewise appear without reported values in the information. Thus, the registry record does not permit a quantitative assessment of the monitoring outcomes.

The single-group design provides no concurrent control comparison. It cannot estimate how outcomes would differ under another model of care, and any observed within-group pattern would not by itself identify the cause of that pattern. The record lists allocation as not applicable and masking as none.

The enrollment is 10, limiting the scale of the group described. The registry record does not report a sample-size justification, so it is not possible to assess the enrollment against a stated precision goal or planned hypothesis test. The record also does not report confidence intervals for the primary endpoint.

Several operational details that could affect interpretation are not reported in the registry record. These include the treatment of missed monitoring records, the handling of incomplete observation periods, the analysis population for each outcome, and the approach to multiplicity across the listed outcomes. The record does not give further detail about adherence to the non-glucose monitoring tasks or actual use of the devices and app.

Safety interpretation is also limited to the registry’s event counts. No serious adverse events, other adverse events, or deaths are listed, but event definitions, ascertainment methods, and follow-up details are not reported. Finally, the planning framework described for sample-size illustrations uses hypothetical two-arm assumptions, unlike the single-group study design. Those illustrations should not be treated as results or as a design justification.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: The Virtual Visit for Women With Gestational Diabetes — NCT02960295.
• Registry record last updated 2019-02-26; status last verified 2019-02.
• Results first posted 2019-02-26.
• 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.

19. Record Summary

The registry describes a completed feasibility study, NCT02960295, titled The Virtual Visit for Women With Gestational Diabetes. It lists 10 participants, a single-group Virtual Visit model, no masking, and no randomized allocation. The study focused on women with gestational diabetes and combined home monitoring with caregiver visits.

The primary endpoint was compliance with the requested frequency of glucose measurements, summarized as the mean number of checks per patient per day, with a standard deviation. The registry also names three secondary outcomes covering self-weighing compliance, blood-pressure-checking compliance, and glucose concentrations. The primary endpoint result and secondary outcome results are not reported in the registry record.

The adverse-event summary lists zero serious adverse events, zero other adverse events, and zero deaths in the Virtual Visit group, with 10 at risk in each category. The record does not describe a comparator group, report the analysis methods in detail, or explain missing-data handling or multiplicity.