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 Effect of a Unique Web-based Behaviour Change Program on Weight Loss and Cardiovascular Risk Factors (NCT01472276), a randomized phase 2 study. The primary outcome is Weight Loss Kg.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01472276 |
| Phase | Phase 2 |
| Condition | Obesity |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 65 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Queen's University, Belfast |
| Results posted | Yes |
2. Clinical Question
Population
Adults who were overweight or obese and at high risk of cardiovascular disease. The registry lists obesity as the condition and describes the target group as people with excess weight and elevated cardiovascular risk.
Intervention
A web-based behaviour change program intended to address physical activity and weight management. The brief description characterizes it as interactive; further details of its content or delivery are not reported in the registry record.
Comparator
A control group. The control arm description is blank, so the nature of usual care or any other activities in that group is not reported in the registry record.
Primary question
What was the mean change in weight from baseline to the 3-month follow-up in each group, among participants included in the complete-case analysis? The registry describes the endpoint as a between-group change, but the posted estimates are arm-specific means with confidence intervals rather than a direct between-group estimate.
3. Trial Design
The registry identifies this as a randomized, parallel-group phase 2 trial with no masking. It enrolled 65 participants and is marked completed. The listed sponsor is Queen's University, Belfast. The study start is recorded as 2011-04, and primary completion as 2013-03.
The two arms are labelled Control and Web-based Program. The program is classified as a behavioural intervention; no further arm description is given for either group. In particular, the control group's activities and the program's specific components are not reported in the registry record. The brief summary describes an interactive web-based behaviour change program focused on physical activity and weight management for people at high cardiovascular risk.
The primary outcome is weight loss in kilograms at 3 months, described as the change from baseline. The outcome population is identified as complete-case, and the posted arm summaries include 32 participants in the control group and 25 in the web-based program group. These outcome counts are distinct from the enrollment figure; reasons for the difference and the handling of participants without complete outcome data are not reported in the registry record.
The registry also names secondary outcomes covering physical activity, seated systolic and diastolic blood pressure, biochemical markers of cardiovascular risk, dietary intake, pulse wave analysis, quality of life, and sleep quality. It lists 11 secondary outcomes as posted and 12 outcome measures overall. Their numerical results are not included in the registry record described for this analysis. The registry record reports no analysis records, so additional model specifications and analysis details are not reported.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Control | Web-based Program |
|---|---|---|
| STARTED | 33 | 32 |
| 3-month Follow-up | 32 | 25 |
| 6-month Follow-up | 31 | 21 |
| COMPLETED | 29 | 17 |
| NOT COMPLETED | 4 | 15 |
Analysis population for the primary outcome, as defined in the registry: Weight (kg) outcome differences within study groups from baseline to 3 months (complete-case analysis).
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 | Control | Web-based Program | Total |
|---|---|---|---|---|
| Participants analysed | 33 | 32 | 65 | |
| Age, Continuous | years | 52.9 (SD 7.27) | 51.4 (SD 7.59) | 52.1 (SD 7.4) |
| Sex: Female, Male: Female | Participants | 20 | 16 | 36 |
| Sex: Female, Male: Male | Participants | 13 | 16 | 29 |
6. Primary Endpoint
The registry lists the primary outcome as Weight Loss Kg, measured over 3 months.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | kg |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is weight change in kilograms from baseline to the 3-month follow-up. Weight is a continuous measure, and the registry reports the mean change within each group, together with a 95% confidence interval. A negative change represents a reduction in weight under the sign convention used in the posted estimates.
Weight is used as a direct measure of the weight-management outcome the program was intended to address. Reporting change from baseline focuses on how the measured value shifted during follow-up, rather than only comparing participants' final weights. The mean describes the average change among those included in the analysis; it does not show how much individual participants varied unless a measure of dispersion is also reported.
The endpoint description refers to a between-group change, but the available results give a mean and confidence interval for each arm separately. A direct estimate of the difference between the groups, with its uncertainty, is not reported in the registry record. Arm-specific changes can describe what was observed within each group, but they do not by themselves quantify the treatment contrast. The registry specifies a 3-month timeframe; longer-term weight change is not reported in this primary endpoint description.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
For the control group, the posted mean weight change was -0.53 kg, with a 95% confidence interval from -1.6 to 0.54. For the web-based program group, the mean change was -4.37 kg, with a 95% confidence interval from -5.8 to -2.94. Both are arm-specific complete-case summaries at the 3-month follow-up.
The interval for the control-group mean includes zero. The interval for the web-based program group's mean lies below zero. These features describe the uncertainty around each group's mean change; they are not a test of whether the groups differ. A confidence interval around a within-group mean does not replace a confidence interval around a between-group contrast. The registry record does not report a direct contrast estimate, its confidence interval, or a p-value for the primary outcome.
The numerical estimates appear different in direction and size, but no subtraction or comparative test is reported. It would therefore be inappropriate to treat the arm-specific intervals as proof of a difference between groups. In particular, whether one interval includes zero and the other does not is not itself a valid statistical test of the difference between the arms. The posted data support describing the two observed group means and the precision of each estimate, not making a definitive comparative inference.
The confidence intervals also indicate that the estimates are not exact. General explanation: a confidence interval expresses the uncertainty associated with an estimated mean under the analysis assumptions; it is not a range containing every participant's change. The registry reports the interval limits but does not describe the method used to calculate them. The outcome analysis is identified as complete-case, so the estimates pertain to participants with the required outcome data rather than automatically representing all enrolled participants.
The result is limited to the stated endpoint and follow-up. Although the registry lists secondary outcomes relating to activity, cardiovascular risk markers, diet, quality of life, and sleep, numerical findings for those outcomes are not reported in the record. The posted primary outcome alone cannot establish what happened on those other measures or whether the program affected cardiovascular risk more broadly.
9. Statistical Methods Explained
The registry describes the primary measure as a mean of a continuous outcome. A continuous measure can take values across a scale rather than belonging to a set of categories. In this trial, the measure is weight change in kilograms. The reported mean summarizes the average change among the participants included in each arm's outcome analysis. It does not imply that every participant changed by the mean amount, and it does not describe the distribution of individual changes.
The estimates are accompanied by 95% confidence intervals. General explanation: a confidence interval communicates the precision of an estimate under the assumptions of the statistical method used. A narrower interval indicates greater precision than a wider interval, while the interval limits indicate values compatible with the estimate under that method. The interval does not describe the range of individual participant outcomes. The registry gives the intervals but does not report the calculation method or any adjustment model.
A key distinction is between a within-arm estimate and a between-arm comparison. The posted figures are means for the control and web-based program groups individually. A comparative analysis would estimate the difference between those groups and report uncertainty for that difference. The registry's primary outcome description refers to between-group change, but a numerical contrast and its uncertainty are not reported in the record. It is therefore not possible to infer a formal treatment comparison from the group means alone. General explanation: the uncertainty of a contrast depends on the uncertainty and relationship between the group estimates; comparing separate confidence intervals is not a substitute for estimating the contrast directly.
The outcome population is described as complete-case. General explanation: a complete-case analysis uses participants with the data needed for the outcome analysis and excludes cases with missing required measurements. Such an analysis can be affected if missingness is related to outcomes or differs systematically among participants. The registry does not report the number missing for the primary endpoint, reasons for missingness, or any imputation or sensitivity analysis. The reported outcome counts are 32 in the control group and 25 in the program group, while total enrollment was 65; the record does not explain the difference.
The trial is identified as randomized and parallel-group, which means participants were assigned to one of two groups and the groups were followed as separate arms. It is also identified as unmasked. General explanation: masking is intended to limit the influence of knowledge about group assignment on aspects of trial conduct or outcome assessment. For a weight measure, the registry does not state who collected or assessed the measurements, or whether any safeguards were used. Allocation concealment and the details of randomization are not reported in the registry record.
The registry reports a planning illustration based on the observed effect, using a two-sided significance level of 0.05, equal allocation, and a normal approximation. The illustration considers detecting a stated fraction of the observed effect. General explanation: such values are planning scenarios, not evidence that a trial had a particular probability of finding a result, and not a measure of observed power. The registry does not report its original sample-size justification, so the planning illustration should not be taken as the trial's own design calculation.
General explanation: over-dispersion matters when outcome variation is greater than assumed by a statistical model, because standard errors and confidence intervals may then be too optimistic. The primary endpoint is continuous, but the registry does not report a variance estimate or model details that would allow an assessment of this issue. Likewise, the record does not state whether covariates were included, whether baseline weight was incorporated through a model, or whether the estimate was adjusted for other factors. No such methods should be assumed from the arm summaries alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 12 outcome measures overall and 11 secondary outcomes as posted. The named secondary outcomes cover physical activity, seated systolic and diastolic blood pressure, biochemical markers of cardiovascular risk, dietary intake, pulse wave analysis, quality of life, and sleep quality. Multiple outcomes can create a multiplicity issue: when many hypotheses are assessed, the chance of at least one apparently unusual result may increase. General explanation: methods such as a prespecified hierarchy or an adjustment for multiple comparisons can address this concern, but the registry does not report whether either was used.
The posted primary outcome is identified as a complete-case analysis. The registry does not report missing-data counts or reasons, the amount of missingness by arm beyond the outcome analysis counts, or any imputation, sensitivity analysis, or other strategy for handling missing values. It also does not report whether the analysis followed an intention-to-treat population, whether participants were analyzed according to randomized assignment, or whether a per-protocol population was defined. The complete-case description should not be taken as evidence of any unreported analysis population.
The registry record reports zero analysis records. It does not describe interim analyses, stopping rules, a statistical analysis plan, or multiplicity procedures. Those details are therefore not reported in the registry record. Their absence means the posted arm summaries cannot be used to determine how analyses of other outcomes were selected or interpreted.
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 |
|---|---|---|---|
| Control | 0 | 33 | 0.0% |
| Web-based Program | 0 | 32 | 0.0% |
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 |
|---|---|
| Control | 0 of 33 |
| Web-based Program | 0 of 32 |
The registry lists no serious adverse events in the control group among 33 participants at risk and none in the web-based program group among 32 participants at risk. It also lists no other adverse events in the control group among 33 participants at risk and none in the program group among 32 participants at risk. No serious adverse-event terms are listed.
These figures describe what was recorded in the registry, not proof that no adverse events occurred outside the reported collection or reporting process. The safety denominators differ from the primary-outcome counts, and the record does not explain the relationship between those populations. Deaths are not reported in the registry record; a blank or unavailable death value should not be read as a reported count of zero. The adverse-event information should be interpreted as registry reporting, with no further detail about event definitions, collection methods, or follow-up provided.
12. What the Result Does, and Does Not, Mean
The posted primary outcome describes mean weight change over the 3-month follow-up among complete cases in each group. The control-group mean was -0.53 kg, and the web-based program group's mean was -4.37 kg. The respective 95% confidence intervals were -1.6 to 0.54 and -5.8 to -2.94. These estimates and intervals describe the observed arm-level changes and their reported precision.
They do not, by themselves, establish the size or statistical uncertainty of the difference between groups. The record does not post a direct comparative estimate or p-value for the primary endpoint. Nor does the arm-level result establish that the web-based program caused the observed change: the registry entries available for interpretation do not include sufficient comparative analysis details to support that conclusion. The study is randomized, but the posted estimates remain separate group summaries.
The endpoint is limited to weight change at 3 months. The registry lists other outcomes, but their numerical results are not reported in the record. No conclusion about physical activity, blood pressure, biochemical markers, diet, pulse wave analysis, quality of life, or sleep quality follows from the primary weight outcome alone. The safety listings likewise contain no reported adverse events for the stated groups and denominators, but deaths are not reported and event-collection details are absent.
General explanation: statistical evidence and practical importance are distinct. A confidence interval helps show uncertainty in an estimate, while judgments about meaningful change require relevant clinical context and thresholds. Those thresholds are not reported in the registry record. Accordingly, the result is best read as a set of short-term, complete-case group summaries, with a direct between-group inference and broader clinical interpretation not established by the posted primary estimates.
13. Why This Trial Matters Statistically
This trial illustrates why outcome summaries and treatment comparisons should not be confused. The registry presents a mean change and confidence interval for each randomized arm, while its primary outcome description refers to a between-group change. Without a direct contrast estimate and its uncertainty, the arm summaries cannot answer the comparative question with the same clarity as an explicitly reported between-group analysis.
It also highlights the importance of stating the analysis population. The primary outcome is complete-case, and its arm counts differ from total enrollment. Without missing-data details, readers cannot assess whether the analyzed participants are representative of everyone enrolled or how missing outcomes may affect the estimates. This is a general concern for trial interpretation, not evidence that the complete-case estimates are necessarily biased.
The record further illustrates the need to distinguish outcome scope from outcome availability. Several secondary domains are listed, but numerical results for them are not reported in the record. A list of planned or registered outcomes is not equivalent to a set of analyzed findings. Likewise, the absence of reported adverse events is not the same as a comprehensive account of safety when collection details and death counts are not available.
Finally, the planning illustration should be kept separate from the trial's original design rationale and from observed power. It is based on the observed effect under stated assumptions, while the registry does not report the trial's own sample-size justification. These distinctions help readers focus on what is actually estimated, how uncertain it is, and which questions remain unanswered by the registry record.
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 the primary result is that the registry reports arm-specific means and confidence intervals but no direct between-group estimate, confidence interval, or p-value. Although the outcome description characterizes the endpoint as a between-group change, the available figures do not quantify that contrast. The posted estimates should therefore be treated as descriptive arm summaries rather than a complete comparative analysis.
The analysis is described as complete-case, but missing-data information is sparse. The registry does not report why the primary-outcome counts differ from enrollment, how many participants lacked follow-up weight data, whether missingness differed by group, or whether sensitivity analyses were conducted. The method used to construct the confidence intervals and any adjustment for baseline values or other covariates are also not reported.
Further trial details that could affect interpretation are absent. The registry does not describe the control condition, the program's components, the randomization procedure, allocation concealment, or the weight measurement process. It identifies the trial as unmasked but does not report who assessed the outcome. The original sample-size justification, interim analyses, and statistical analysis plan are not reported in the registry record.
The primary endpoint covers a 3-month follow-up, so the posted result does not establish longer-term weight change. Although secondary outcomes are listed, numerical results for them are not described in the record used for this analysis. Safety reporting also has limits: event definitions and collection methods are not reported, and deaths are not reported in the registry record. These gaps constrain the conclusions that can be drawn from the posted information.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Effect of a Unique Web-based Behaviour Change Program on Weight Loss and Cardiovascular Risk Factors — NCT01472276.
- Registry record last updated 2023-05-01; status last verified 2022-06.
- Results first posted 2023-05-01.
- 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
NCT01472276 is a completed, randomized, unmasked, parallel-group phase 2 trial sponsored by Queen's University, Belfast. The registry records enrollment of 65 and a primary completion date of 2013-03. The study concerned a web-based behaviour change program for weight management and cardiovascular risk factors in adults who were overweight or obese and at high cardiovascular risk.
The primary endpoint was mean weight change from baseline to 3 months, analyzed among complete cases. The control mean was -0.53 kg, with a 95% confidence interval from -1.6 to 0.54; the web-based program mean was -4.37 kg, with a 95% confidence interval from -5.8 to -2.94. A direct between-group estimate is not reported in the registry record. The registry lists secondary outcomes across several health domains, but their numerical findings are not reported in the record.