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 Dissemination of Findings Fast Using Online-videos Trial (NCT02109159), a randomized na study. The primary outcome is Number of Participants Who Forwarded the Video.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02109159 |
| Phase | NA |
| Condition | Information Seeking Behavior |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 8353 |
| Arms in the primary outcome | n/a |
| Lead sponsor | London School of Hygiene and Tropical Medicine |
| Results posted | Yes |
2. Clinical Question
Population
Clinicians and researchers in obstetrics and gynecology were selected as participants. The registry record reports total enrollment of 8353, but does not describe the characteristics of participants who completed the study or contributed to each outcome.
Intervention
Participants assigned to the emotional-content arm received a short online video featuring an interview with a postpartum hemorrhage survivor and her husband describing their experience. The videos concerned the WOMAN trial.
Comparator
The control video presented the same information with less emotional content: the WOMAN trial coordinator discussed the survivor’s and her husband’s experience. The registry describes the two videos as otherwise identical.
Primary question
The trial asked whether emotional content affected the number of participants who forwarded the video. Participants were emailed a link, asked to watch the video, and invited to forward it to colleagues if they found it helpful. The primary endpoint was forwarding after 14 days of sending the videos. The registry also identifies the number of video accesses generated through sharing as a secondary outcome.
3. Trial Design
The registry describes a randomized, double-masked, parallel-group trial with two video arms. One arm received a short video with emotional content, featuring a survivor of postpartum hemorrhage and her husband. The control arm received a less emotional video in which the WOMAN trial coordinator talked about the same experience. Both videos concerned the WOMAN trial and were described as approximately 2.5 minutes long and otherwise identical.
Participants were selected from clinicians and researchers in obstetrics and gynecology. An email containing a link to one of the videos was to be sent to each participant. The email asked participants to watch the video and forward its link to colleagues if they found it helpful. A computer programme was used to track access to the videos and determine forwarding. The planned data-collection period was 14 days after the emails were sent.
The registry lists enrollment of 8353, a start date of 2014-12, primary completion in 2015-03, and a completed status. It identifies the London School of Hygiene and Tropical Medicine as sponsor. The masking description does not specify which people were masked or how masking was maintained. The method used to generate the random allocation sequence, conceal allocation, or handle departures from assigned video is not reported in the registry record. Details of participant flow and the number analyzed in each arm are also not reported in the registry record.
The primary outcome was the number of participants who forwarded the video. The secondary outcome concerned video access generated through sharing by each participant. Although the record describes these outcomes and the trial’s design, it does not report an arm-by-arm result for the primary endpoint.
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 | Emotional Video | Control Video |
|---|---|---|
| STARTED | 4178 | 4175 |
| COMPLETED | 4178 | 4175 |
| NOT COMPLETED | 0 | 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 | Emotional Video | Control Video | Total |
|---|---|---|---|---|
| Participants analysed | 4178 | 4175 | 8353 | |
| Age, Customized: Unknown | participants | 4178 | 4175 | 8353 |
| Sex/Gender, Customized: Unknown | participants | 4178 | 4175 | 8353 |
| Economic classification of countries: Low income countries | participants | 464 | 457 | 921 |
| Economic classification of countries: Lower-middle income countries | participants | 934 | 844 | 1778 |
| Economic classification of countries: Upper-middle income countries | participants | 507 | 543 | 1050 |
| Economic classification of countries: High income countries | participants | 2273 | 2331 | 4604 |
| Source of contact: WOMAN trial contact list | participants | 1308 | 1263 | 2571 |
| Source of contact: Journals | participants | 2870 | 2912 | 5782 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants Who Forwarded the Video, measured over After 14 days of sending the online videos.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint counts participants who forwarded the video. It is a binary participant-level outcome: each participant either forwarded the link or did not. The registry says a computer programme tracked access to the videos and that forwarding would be identified from data collected with that programme. The stated timeframe is after 14 days of sending the online videos.
Forwarding was chosen to represent dissemination. A forwarded link can extend a video’s reach beyond the people who received the original email, so the endpoint focuses on a sharing action rather than solely on whether the original recipient watched the video. The secondary outcome, access generated through sharing, captures a different aspect of reach: the number of accesses attributed to a participant’s sharing.
These measures should not be treated as interchangeable. A forwarding count concerns people who shared a link; an access count concerns video visits generated through sharing. The registry record does not report definitions for repeat accesses, how forwarding was distinguished from other link distribution, or how access was attributed to individual participants. Most importantly, it does not report the primary endpoint’s observed counts by group or a statistical comparison. The endpoint is clearly described, but its result cannot be interpreted from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes the question and the randomized comparison: whether an emotional interview format was associated with more forwarding than a less emotional presentation of the same information. It reports total enrollment of 8353 and describes forwarding after 14 days as the primary outcome. It does not report the number of participants who forwarded the video in either arm, an effect estimate, a confidence interval, or a p-value. The primary outcome therefore cannot be quantified or compared between groups using the registry record.
The posted adverse-event figures are not a substitute for the primary result. They list zero serious adverse events and zero other adverse events for the emotional-video group, with 4178 at risk, and for the control-video group, with 4175 at risk. These are safety figures, not forwarding results. They do not indicate how often videos were shared or accessed.
In general, a randomized comparison is intended to estimate the effect of assignment to one intervention rather than another. For this trial, the relevant contrast would concern assignment to the emotional video versus assignment to the less emotional video. A complete interpretation would need the observed forwarding outcomes in each group, the statistical contrast between them, and an indication of uncertainty. Those results are not reported in the registry record. Without them, it is not possible to tell from this record whether forwarding differed, how large any difference was, or how precise an estimate might be.
The registry describes an additional outcome based on access generated through sharing, but does not report its result either. Even if access data were available, they would answer a related but distinct question: the amount of video traffic attributed to sharing rather than the proportion of participants who forwarded a link. Neither outcome is presented with a reported statistical comparison in this record.
Accordingly, the appropriate reading is limited. The registry provides a trial design and endpoint description, not a numerical efficacy result. Absence of a result in the registry record should not be interpreted as evidence that the two video formats produced the same forwarding behavior, nor as evidence that one produced more. A result with an estimate and uncertainty, alongside clear analysis details, would be needed to assess the strength and precision of the comparison.
9. Statistical Methods Explained
What kind of outcome is forwarding?
Forwarding is a binary participant-level outcome because a participant either forwarded the link or did not. For a binary outcome, a group result is usually expressed as the number of participants with the event and the number assessed, with an effect measure comparing the randomized groups. Common effect measures include a difference in event proportions and a relative measure. These measures answer different questions: an absolute contrast describes the change in event frequency, while a relative contrast compares frequencies proportionally. The registry record does not report group-specific forwarding counts or an effect estimate, so no such contrast can be interpreted for this trial.
The secondary access outcome is a count, not the same binary outcome. Counts may vary substantially between participants, and a small number of participants can account for many accesses. In general, count-data analyses need to reflect how the counts vary. Over-dispersion occurs when the observed variability is greater than a model assumes; if it is ignored, uncertainty may be understated. The record does not report the distribution of access counts or the statistical model used for that endpoint.
What does randomization contribute?
Random allocation is intended to make the groups comparable, on average, with respect to both measured and unmeasured participant characteristics. It supports a comparison of assignment to the emotional video with assignment to the less emotional video. Randomization does not guarantee that the groups will be identical, nor does the word “randomized” alone describe the method used to generate or conceal allocation. Those procedural details are not reported in the registry record.
In general, an analysis based on participants’ assigned groups estimates the effect of assignment, even if some participants do not follow their assignment. An analysis based on the video actually viewed or another subset may answer a different question and can lose the protection offered by randomization. The registry record does not state which analysis population was used, how non-viewing or non-forwarding was handled, or whether any participants were excluded from analysis.
How should uncertainty be assessed?
A confidence interval describes a range of effect estimates compatible with the data and the assumptions of the analysis. Its width conveys precision: a wider interval indicates less precision, while a narrower interval indicates more. A p-value addresses how compatible the observed data are with a specified null hypothesis under the model; it does not measure the size or practical importance of an effect. Neither a confidence interval nor a p-value for the primary outcome is reported in the registry record. Without an estimate and its uncertainty, the direction, magnitude, and precision of a forwarding comparison cannot be assessed.
What can a planning illustration tell readers?
Sample-size planning asks how many participants would be needed under chosen assumptions to detect a specified effect with a specified probability, using a chosen significance level and allocation. Such calculations depend on assumptions about the event frequency and effect size. A planning illustration based on an observed effect is conditional on that effect and should not be mistaken for observed power or as a substitute for the trial’s actual result. The record describes a planning approach based on a stated fraction of an observed effect, two-sided significance level 0.05, equal allocation, and a normal approximation. It does not report the trial’s own sample-size justification in the registry record. A planning calculation cannot establish whether a treatment or communication format had an effect.
What statistical analysis was specified?
The registry record describes the primary outcome and how video access was tracked, but it does not report the statistical test or model for the primary outcome, any adjustment variables, or how missing observations were handled. It does not report a confidence level for intervals, a primary analysis population, or details of interim analyses. These items should not be inferred from the randomized design or from the fact that the endpoint is binary. Without the analysis specification and arm-level results, readers cannot verify how the primary comparison was conducted or reproduce it from the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists two outcome measures and four analyses, but does not explain how the analyses relate to the outcomes, whether any were prespecified as primary analyses, or how multiple comparisons were handled. When several outcomes, time points, or analyses are examined, the chance of obtaining an apparently notable result by chance can increase. In general, a statistical plan may address this through a hierarchy of outcomes, adjustment procedures, or a clear distinction between confirmatory and exploratory analyses. Such details are not reported in the registry record. The record’s designation of forwarding as the primary outcome identifies its stated priority, but does not by itself describe multiplicity control.
The registry does not report participant flow for the primary outcome, the number with missing forwarding status, or the way any missing data were treated. The video-tracking programme is described, but this does not establish that tracking data were complete or that every participant’s status could be classified. In general, missingness can affect interpretation if the probability of an unavailable outcome differs between groups or is related to forwarding behavior. The record does not provide enough information to assess that possibility.
Analysis populations are also not described. The registry record does not state whether participants were analyzed according to assigned group, whether only participants who watched a video were included, or how deviations from assignment were treated. Those choices affect what comparison an analysis estimates. No participant-level data or analysis population counts are reported for the primary endpoint, so the impact of exclusions or incomplete follow-up cannot be assessed.
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 |
|---|---|---|---|
| Emotional Video | 0 | 4178 | 0.0% |
| Control Video | 0 | 4175 | 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 |
|---|---|
| Emotional Video | 0 of 4178 |
| Control Video | 0 of 4175 |
The registry lists zero serious adverse events and zero other adverse events in the emotional-video group, among 4178 participants at risk. It also lists zero serious adverse events and zero other adverse events in the control-video group, among 4175 participants at risk. These figures are recorded separately from the video-forwarding endpoint and do not supply evidence about dissemination.
Zero reported events means that the registry record lists no events in those categories for the stated groups. It does not establish that every possible adverse experience was actively sought, that all events were captured, or that the categories were defined in a particular way. The adverse-event terms and details of ascertainment are not reported in the registry record. The record also does not describe how these safety counts were analyzed or whether any participants lacked safety follow-up.
These figures should therefore be read as registry-reported counts, not as a comprehensive assessment of safety or as proof that no adverse experience occurred. They also do not affect interpretation of the primary outcome: the record still lacks a reported comparison of forwarding between the video groups.
12. What the Result Does, and Does Not, Mean
The record describes a randomized comparison of two ways of presenting information about the WOMAN trial: an emotional interview with a postpartum hemorrhage survivor and her husband, and a less emotional presentation by the trial coordinator. Its central statistical question is whether the emotional content changed video forwarding among participating clinicians and researchers in obstetrics and gynecology. This is a question about communication and dissemination behavior, not a direct comparison of medical treatments.
The registry identifies forwarding as the primary endpoint and access generated through sharing as a secondary outcome. It also gives an enrollment total and a data-collection timeframe. Those details make the intended outcome and setting understandable. However, the registry record does not report the group-specific forwarding results, a treatment-effect estimate, or its uncertainty. It therefore does not show whether forwarding differed between groups, how large a difference might have been, or how precisely it was estimated. The secondary access result is also not reported.
Even a complete result would need to be interpreted in light of what was measured. Forwarding a link is a specific action prompted by an email that asked participants to share the video if they found it helpful. It is not the same as watching the video, understanding or remembering its content, changing clinical practice, or improving a health outcome. Access generated through sharing is another measure of reach, not a measure of clinical benefit.
In general, randomized assignment can strengthen a causal comparison of the assigned formats, provided the analysis and follow-up are appropriate. It cannot, on its own, resolve questions about missing tracking data, the completeness of outcome ascertainment, or applicability to people outside the recruited group. Those details are not reported in the registry record. The defensible conclusion is that the record describes a trial designed to assess video forwarding but does not provide results that establish the observed effect or its precision.
13. Why This Trial Matters Statistically
This trial illustrates how a clinical trial can study behavior surrounding research communication rather than a clinical treatment outcome. Its primary endpoint was whether a participant forwarded an online video. That distinction matters statistically: a well-defined behavior can be measured at the participant level, but it remains a proxy for broader dissemination and does not automatically represent what happened to viewers who received a forwarded link.
The contrast also raises the importance of isolating the feature under study. The record describes two videos with the same information, one using a first-hand interview and one using a coordinator’s account, and says they were otherwise identical. The intended comparison is therefore framed around emotional content. In general, any difference in forwarding would be interpreted as a difference associated with assignment to these video formats, within the trial’s setting and measurement approach.
For statistical interpretation, a clear endpoint is only one part of the evidence. Readers also need observed group results, an effect estimate, uncertainty, and analysis details. The registry record describes the endpoint and design but does not report the primary comparison. This makes the trial a useful example of the difference between a research question and a reported result: knowing that a randomized study was conducted does not reveal the direction, magnitude, or precision of its findings.
The trial also shows why dissemination measures should not be conflated. A participant forwarding a link, and accesses attributed to sharing, are related but distinct outcomes. Their meaning depends on how sharing and access were tracked. The record states that a computer programme tracked access, while leaving details about attribution and analysis unreported. Statistical conclusions should remain aligned with the outcome actually measured and the information actually reported.
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 trial’s setting and outcome constrain what can be inferred. Participants were selected from clinicians and researchers in obstetrics and gynecology, so the registry description does not establish how the same videos would be shared by other audiences. The email asked participants to forward the link if they found the video helpful. Forwarding therefore reflects behavior within that invitation and context; it should not be treated as a general measure of spontaneous sharing without qualification.
The primary outcome was forwarding during the period after the emails were sent, with the stated timeframe after 14 days. This is a bounded measure of sharing behavior, not a measure of longer-term circulation, viewing, retention, or clinical impact. The secondary outcome of access generated through sharing may capture reach, but its interpretation depends on how repeat access and attribution were handled. Those details are not reported in the registry record.
The registry does not provide the primary outcome counts by group, the number of participants included in each analysis, or information about missing tracking data. It also does not report the allocation procedure, the identities of people who were masked, the statistical model, or the analysis population. These omissions prevent assessment of whether the reported design was implemented as intended and how any incomplete data were addressed.
Finally, the registry record does not report the primary effect estimate or uncertainty. The absence of those results prevents assessment of the direction, size, and precision of the comparison. The listed adverse-event counts do not resolve this limitation because they concern different outcomes.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Dissemination of Findings Fast Using Online-videos Trial — NCT02109159.
- Registry record last updated 2016-12-28; status last verified 2016-06.
- Results first posted 2016-12-28.
- 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
The registry describes a completed, randomized, double-masked, parallel-group trial sponsored by the London School of Hygiene and Tropical Medicine. Enrollment was 8353. The record lists a start date of 2014-12 and primary completion in 2015-03.
Participants selected from clinicians and researchers in obstetrics and gynecology were assigned to receive a short emotional or less emotional online video concerning the WOMAN trial. The primary endpoint was the number of participants who forwarded the video after 14 days of sending the emails. Video access generated through sharing was listed as a secondary outcome.
The record does not report the primary outcome comparison, group-specific forwarding counts, an effect estimate, or its uncertainty. It lists zero serious and zero other adverse events in each group, with 4178 at risk in the emotional-video group and 4175 at risk in the control-video group. Analysis populations, missing-data handling, and the statistical method for the primary comparison are not reported in the registry record.