Avoidance of Hyperglycaemia in People With Type 1 Diabetes: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Avoidance of Hyperglycaemia in People With Type 1 Diabetes (NCT04732780), a registered phase not stated study. The primary outcome is Hyperglycaemia Avoidance Scale.

2. Clinical Question

In practical terms, the study is intended to characterize questionnaire responses and explore participants’ experiences, rather than estimate the effect of an assigned treatment. The registry identifies a primary scale measure, but does not state a specific association, prediction, or group-difference question. The interview component is described as an opportunity to gain further understanding, not as a randomized or controlled comparison.

3. Trial Design

The registry record describes a completed study sponsored by Imperial College London. Its stated aim is to learn more about avoidance of hyperglycaemia in adults with type 1 diabetes. People attending a type 1 diabetes clinic were to be invited to complete self-report questionnaires and a survey. A subsection of people who experience avoidance of hyperglycaemia were to be invited to an interview. The record does not provide details of interview sampling, interview procedures, or how questionnaire and interview information would be combined.

No intervention is listed, and the registry describes a Questionnaire Group rather than treatment and control arms. Allocation is not stated. Accordingly, the record does not describe a randomized comparison or a like-for-like control comparison. The primary outcome is a continuous score on the Hyperglycaemia Avoidance Scale, recorded at baseline. The record lists 7 outcome measures, but it does not report the results of the primary measure or the other outcomes.

Enrollment is listed as 253. The study start date is 2021-03-02, the primary completion date is 2021-11-15, and the status is COMPLETED. These registry entries describe the study’s administrative record; they do not establish how many participants completed each questionnaire, contributed to each analysis, or took part in interviews. Those details are not reported in the registry record.

The record lists no analysis entries. It also does not report a statistical analysis plan, sample-size justification for the study itself, or details of data collection beyond the brief description. The separate planning illustrations use assumptions for a two-arm comparison and are not a description of the study’s design or an observed-power calculation.

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

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.

6. Primary Endpoint

The registry lists the primary outcome as Hyperglycaemia Avoidance Scale, measured over Baseline.

The primary endpoint is the Hyperglycaemia Avoidance Scale score at baseline. The registry describes it as a questionnaire measure scored 0-96, with higher scores suggesting greater hyperglycaemia avoidance. It is treated as a continuous measure, and the intended summary is a mean with a standard deviation.

A scale score gives a numerical summary of responses to questionnaire items. A mean describes the average score in the group being summarized, while a standard deviation describes how spread out individual scores are around that average. Together, these summaries can describe both the typical level of reported avoidance and the variation in responses. They do not, by themselves, show why people differ or whether one factor caused another.

The score is relevant to the study’s stated aim of learning about hyperglycaemia avoidance. Its direction is specified: higher scores suggest greater avoidance. The registry record does not report the observed mean or standard deviation, nor does it provide information about the scale’s measurement properties, interpretation thresholds, or the handling of incomplete responses. Those details are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry classifies the primary outcome as a continuous measure and names the mean and standard deviation as its summary. The outcome is the baseline Hyperglycaemia Avoidance Scale score, described as ranging from 0-96. No inferential analysis is listed in the record. The explanations below describe the statistical ideas relevant to this type of measure in general; they should not be read as a claim that these methods were used for this study.

What does a mean describe?

In general, a mean is the arithmetic average of the observed values. For a questionnaire score, it provides a concise description of the group’s central score. Its interpretation depends on what the scale measures and how score direction is defined. In this study, the registry says higher scores suggest greater hyperglycaemia avoidance. A mean does not describe every participant’s response, and it does not explain the reasons for differences between participants.

What does a standard deviation add?

In general, the standard deviation describes the spread of observations around the mean. A smaller spread indicates that scores tend to be closer to the average; a larger spread indicates more variation. It is a description of variability among observed scores, not a measure of uncertainty in the mean. The registry names standard deviation as the primary outcome’s dispersion measure, but the value itself is not reported in the registry record.

How is uncertainty different from variability?

In general, an estimate of the mean has sampling uncertainty because the observed participants are not necessarily identical to the wider population of interest. A confidence interval expresses uncertainty around an estimate under a statistical model and its assumptions. It is not a range containing every participant’s score, and it does not remove possible selection or measurement biases. No confidence interval for the primary score is reported in the registry record, so the precision of the mean cannot be assessed from this information.

Why does the study design matter?

Statistical comparisons require a clearly defined contrast. A randomized treatment comparison can estimate differences between assigned groups under its design assumptions. Here, the registry lists no intervention, identifies a Questionnaire Group, and does not state an allocation process or comparator. The record explicitly indicates that the arms are not a like-for-like control comparison. It would therefore be inappropriate to interpret the study as a randomized treatment-effect analysis. The registry description supports a focus on questionnaire and survey responses, with interviews intended to add depth to understanding.

What can planning calculations tell us?

In general, a sample-size calculation asks what amount of information a proposed design would need to detect a specified effect under chosen assumptions. The registry describes planning illustrations based on the observed effect, a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is described as a stated fraction of the observed effect. These are planning illustrations, not the study’s own design justification and not observed power. The registry record does not report a sample-size justification for the study itself. Because the listed study has no intervention or comparator group, the two-arm assumptions do not describe its stated questionnaire design.

Why can over-dispersion matter?

In general, over-dispersion means that data vary more than a statistical model expects. If a model assumes less variation than the data contain, its uncertainty estimates may be too small and its tests may appear more decisive than warranted. This concern is especially relevant to some count-data models. The primary endpoint is described as a continuous scale score, and no fitted model or over-dispersion assessment is reported in the registry record. It would not be appropriate to claim that over-dispersion was present or assessed in this study.

What is known about the analysis?

The record lists 7 outcome measures and 0 analyses. The primary outcome is identified, but the statistical methods used to summarize or compare the outcomes are not reported in the registry record. There is no stated adjustment strategy, model specification, confidence-interval method, or account of how incomplete scale responses would be handled. These omissions limit what can be inferred about the analytic process, independently of the study’s enrollment and completion status.

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("Questionnaire Group")
n   <- c(253)
m   <- c(44.6)
sp  <- c(12.6)
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  Questionnaire Group  253  44.600  12.600  43.040  46.160

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 7 outcome measures and identifies the baseline Hyperglycaemia Avoidance Scale score as primary. Considering multiple outcomes can raise a multiplicity issue when several statistical tests are used: the chance of at least one apparently notable result can increase as more tests are considered. In general, analysis plans may address this through a prespecified hierarchy, adjustment, or a clear distinction between confirmatory and exploratory findings. The registry record does not report such a plan, and it lists 0 analyses. It is therefore not possible to determine whether multiplicity was addressed or how the other outcomes were interpreted.

Information about missing data is also not reported in the registry record. The record does not state how many participants completed the primary questionnaire, whether responses were incomplete, what rules were used to calculate a score when items were missing, or whether any missingness was handled statistically. Enrollment alone does not establish the analysis population for the primary endpoint.

The analysis populations are not described. In particular, the record does not say whether analyses were based on everyone enrolled, participants who completed questionnaires, or another defined group. Details about interview participation and how interviewees were selected are also not reported in the registry record. These gaps prevent assessment of whether the analyzed participants represent the intended clinic population or whether exclusions could have affected the results.

In general, missingness can affect interpretation when the people with observed data differ from those without observed data. Appropriate handling depends on the amount, pattern, and possible causes of missing data; none of those details is reported.

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 record lists the Questionnaire Group with 253 at risk for serious adverse events and 0 affected. It also lists 253 at risk for other adverse events and 0 affected, with 0 deaths. No top serious-event terms are listed.

These are the adverse event counts recorded for the group; they are not a comparison between treatment and control groups. The study lists no intervention, and the record does not describe a comparator. The figures therefore do not estimate a relative safety difference between treatments. They also do not establish that no events occurred outside the categories or reporting scope represented in the registry entry.

The registry record does not provide further details about adverse-event collection, the observation period for these figures, event definitions, or the completeness of safety reporting. A count of 0 affected is a reported count, not proof that the underlying risk is absent. These figures should be read as the registry’s recorded serious and other adverse event counts for the Questionnaire Group, with those reporting limitations in mind.

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

The record establishes that the study was completed and describes an effort to learn about hyperglycaemia avoidance among adults with type 1 diabetes attending a clinic. Questionnaires and a survey were planned, with interviews offered to a subsection of people experiencing avoidance. The registry identifies a baseline Hyperglycaemia Avoidance Scale score as the primary endpoint and states how its direction should be interpreted.

That information does not reveal the participants’ actual scale scores. The mean and standard deviation are not reported in the registry record, and no analysis is listed. There is no reported estimate, confidence interval, or statistical test for the primary measure. It is therefore not possible to characterize the observed score distribution or its precision from the registry information.

The study description also does not support conclusions about treatment effects. No intervention or comparator is listed, and allocation is not stated. The record is not a like-for-like control comparison. A questionnaire score can describe responses, but without a suitable design and analysis it cannot establish that a particular treatment or other factor caused a difference.

In general, statistical results address only the data collected and the questions analyzed. They do not automatically establish clinical importance, explain participants’ experiences, or apply to people unlike those who took part. The registry record does not report scale interpretation thresholds, participant characteristics beyond the stated population, or analysis results that would allow those broader questions to be evaluated.

The most defensible conclusion is about the record itself: it documents the intended measurement and data collection approach, enrollment of 253, a completed status, and the recorded adverse event counts. It does not report the primary endpoint result or an inferential analysis. Claims about the amount of avoidance, factors associated with it, or effects of a treatment are not reported in the registry record.

14. Why This Trial Matters Statistically

This study is statistically interesting because its primary measure is a continuous questionnaire score, while its stated aim is to understand a behavioral experience in adults with type 1 diabetes. Descriptive summaries such as a mean and standard deviation can communicate the center and spread of responses. The record specifies that higher Hyperglycaemia Avoidance Scale scores suggest greater avoidance, giving the score a stated direction.

The design description also matters. The registry lists no intervention and no comparator, and it does not state allocation. This makes the distinction between describing a group and estimating a treatment effect especially important. Enrollment and completion status are not substitutes for outcome estimates, uncertainty measures, or a documented analysis.

The record lists 7 outcome measures, but does not report analysis entries or multiplicity methods. This illustrates why a prespecified primary outcome and transparent reporting of analyses are useful: readers need to know which outcomes were examined and how findings were interpreted. Information on missing responses and analysis populations is also essential for understanding whether a reported summary represents the intended group. Those details are not reported in the registry record.

The planned interviews could add context to questionnaire responses, according to the study description. The registry does not report the interview findings or how they were analyzed, so their contribution cannot be assessed. Overall, the record highlights the value of reporting not only a study’s aim and measure, but also the observed results, uncertainty, analysis approach, and limitations needed for statistical interpretation.

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 main limitation for interpreting this record is that it does not report the primary outcome result. Although the endpoint and its intended summary are identified, the observed mean and standard deviation are not reported in the registry record. No confidence interval, statistical test, or analysis entry is listed. As a result, the distribution and precision of the scale scores cannot be assessed.

The registry description does not provide details on participant selection beyond clinic attendance and invitation, or on eligibility criteria. It does not report the characteristics of those who enrolled, questionnaire completion, interview participation, or how participants were included in analyses. Enrollment of 253 does not establish the number with usable primary endpoint data. The extent and handling of missing data are not reported in the registry record.

The design does not include a stated intervention or comparator, and allocation is not stated. The record indicates that the arms are not a like-for-like control comparison. This limits causal interpretation and does not support a randomized treatment-effect conclusion. The registry also does not report the statistical analysis plan, multiplicity strategy, or a sample-size justification for the study itself.

The scale is described by its range and direction, but information about its measurement properties, score interpretation thresholds, and scoring with incomplete item responses is not reported in the registry record. Interview methods and findings are also not reported. Finally, the adverse event counts lack further context about collection and observation. These limitations concern what can be established from the registry entry and should not be mistaken for evidence that a method or procedure was absent from the study itself.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Avoidance of Hyperglycaemia in People With Type 1 Diabetes — NCT04732780.
• Registry record last updated 2023-08-25; status last verified 2023-08.
• Results first posted 2023-08-25.
• 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 record describes a completed study sponsored by Imperial College London, with enrollment of 253 and a stated population of adults with type 1 diabetes. People attending a type 1 diabetes clinic were to be invited to complete self-report questionnaires and a survey, and a subsection experiencing hyperglycaemia avoidance were to be invited to interview.

No intervention is listed, allocation is not stated, and the record does not describe a like-for-like control comparison. The primary endpoint is the baseline Hyperglycaemia Avoidance Scale score, described as ranging from 0-96, with higher scores suggesting greater avoidance. The intended summary is a mean and standard deviation.

The registry lists 7 outcome measures and 0 analyses. The primary outcome results, analysis methods, missing-data handling, and analysis populations are not reported in the registry record. The adverse event entry lists 0 serious events, 0 other events, and 0 deaths in the Questionnaire Group.