The Effect of Surgeon Emotional Support on Treatment Choice for Low-risk Thyroid Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Effect of Surgeon Emotional Support on Treatment Choice for Low-risk Thyroid Cancer (NCT05132478), a randomized na study. The primary outcome is Treatment Choice.

2. Clinical Question

3. Trial Design

This was a randomized, double-masked, parallel-group study. Participants were assigned to one of two video conditions: a simulated patient-surgeon discussion with emotionally supportive statements, or a standard simulated discussion without those statements. The registry lists the phase as not applicable. It describes the study as a hypothetical choice experiment, which is important for interpreting the endpoint: participants stated what they would choose in a scenario rather than selecting or receiving a treatment as part of the trial.

The intended participants were adults with benign thyroid nodules who had been seen at a UW Health clinic for fine needle biopsy and did not need surgery. The brief summary describes a one-time study visit lasting up to 60 minutes. It says the treatment choice would be collected immediately after the video. The registry lists enrollment as 126, while the brief summary says 118 adults will be enrolled. The record does not explain this difference.

The study began on 2021-11-17, had a primary completion date of 2023-02-07, and is marked completed. The record lists the University of Wisconsin, Madison as sponsor. These status and design details do not substitute for outcome results: the treatment-choice counts by group, an effect estimate, and its uncertainty are not reported in the registry record. The record also does not specify who was masked or how masking was maintained. Random assignment describes how the study intended to allocate participants; without the group outcome data, it does not by itself show whether the video conditions were associated with different choices.

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.

Before assignment: 555 patients were screened, 221 were deemed eligible and invited to participate, 128 consented, 2 participants discontinued after consent prior to randomization, 126 were randomized to start, 2 participants did not complete the survey, and 6 participants who completed the survey greater than 30 days past biopsy, were excluded because they did not meet the eligibility criteria of needing to be within 30 days of their biopsy.

Overall Study

Reasons for not completing this period:

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: Baseline information provided for analysis population.

6. Primary Endpoint

The registry lists the primary outcome as Treatment Choice, measured over post video intervention (up to 60 minutes during the only study visit).

The primary endpoint was treatment choice, measured immediately after participants watched the video. The registry describes asking each participant which option they would choose if they were the patient with thyroid cancer in the scenario: total thyroidectomy or lobectomy. The unit is participants, and the stated timeframe is after the video intervention during the one-time study visit.

This endpoint was used to capture the decision participants expressed in response to the simulated discussion. In general, a stated-choice endpoint can address how people respond to a decision scenario, but it is not the same as observing a real treatment decision or clinical outcome. Here, participants were described as having benign nodules and not needing surgery; the thyroid-cancer treatment choice belonged to the video scenario.

The registry record does not report how many participants chose either option in either group. It also does not report a group comparison or its uncertainty. Although the options are named in the endpoint description, the record does not give enough outcome data to determine the distribution of choices or characterize a difference between conditions. The endpoint therefore identifies what the investigators intended to measure, but the posted results do not allow a conclusion about the observed treatment choices.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does randomization contribute?

In general, randomization assigns participants to study conditions by chance. When implemented as intended, it can reduce systematic differences between groups at the time of assignment and support a comparison of outcomes. It does not guarantee that every group characteristic will be identical, and it cannot replace reporting the observed outcomes. The registry identifies the study as randomized, but details of the sequence generation, allocation concealment, and implementation are not reported in the registry record.

What is the comparison?

The two conditions were videos simulating a patient-surgeon discussion about treatment options for low-risk thyroid cancer. One included emotionally supportive statements and the other did not. The comparison therefore concerns the video conditions. It is not a randomized comparison of thyroidectomy and lobectomy: those procedures were the choices participants were asked to consider in the scenario. The record does not report the group-specific response counts or an effect estimate for the comparison.

How should a choice outcome be analyzed?

In general, an outcome recorded as a choice among options can be described by counting how many participants select each option in each group. An analysis can then compare the distributions or a prespecified contrast. The interpretation depends on the outcome definition, the analysis population, and how missing responses are handled. The registry names total thyroidectomy and lobectomy as the choices, but it flags the primary outcome as having several categories or time points and does not reduce it to a single comparison. The precise outcome coding and statistical model are not reported in the registry record. Without counts and analysis details, no effect estimate can be reconstructed or interpreted.

What do estimates and confidence intervals convey?

In general, an effect estimate describes the observed contrast between groups on a specified scale. A confidence interval describes the range of values compatible with the data and the assumptions of the analysis at its stated confidence level. A narrow interval indicates greater precision than a wide interval, but neither the estimate nor its interval can be assessed without reported values. The registry record does not report a primary effect estimate, confidence interval, or p-value. No claim about statistical significance or precision is therefore supported by the posted results.

What is over-dispersion, and does it apply?

In general, over-dispersion occurs when observed variability in data is greater than a statistical model assumes. It can make uncertainty estimates too small if the model does not account for the extra variation. It is a consideration in some count-data settings, but it cannot be assessed automatically from the fact that an outcome is recorded as participant counts. The registry does not describe an over-dispersion assessment or a model for the primary outcome, and the choice data needed to evaluate such a model are not reported.

What do the planning illustrations mean?

The sample-size assumptions describe planning illustrations, not the trial’s own design rationale. They specify a two-sided significance level of 0.05, equal allocation between arms, a normal approximation, and effects expressed as fractions of the observed effect. In general, such calculations illustrate the number of participants per arm associated with chosen planning assumptions. They are not observed power, do not demonstrate that the study was adequately powered, and are not a substitute for the observed treatment-choice estimate. The registry record does not report a protocol sample-size justification or the planned effect used to design the trial.

The registry identifies eight analyses, but the analysis methods, model specifications, covariate adjustments, and handling of deviations from the assigned video are not reported in the registry record. Therefore, a statistical method should not be inferred from the randomized design alone.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists six outcome measures: the primary treatment-choice outcome and five secondary measures concerning decisional confidence, anxiety, fear, perceived physician empathy, and trust in a physician. It also lists eight analyses. The specific analysis-to-outcome mapping, which outcomes were designated as primary or secondary for testing, and any multiplicity procedure are not reported in the registry record.

Multiplicity is a general issue that arises when several statistical hypotheses are tested. As the number of tests grows, the chance of at least one apparently unusual result can increase if each test is interpreted separately without accounting for the set of tests. Whether and how that concern was addressed in this study cannot be determined from the record. No correction, hierarchy, or other testing strategy should be assumed.

Missing-data methods are also not reported in the registry record. There is no account of incomplete video exposure, unanswered treatment-choice questions, missing secondary scores, or how any such observations were handled. The enrollment field lists 126, while the brief summary describes enrolling 118 adults; the record does not explain that difference or give a participant flow. The safety denominators are not a substitute for endpoint-specific analysis counts.

The record does not define the analysis population, such as whether the primary comparison included all randomized participants or only those with a recorded response. It also does not report exclusions, protocol deviations, or sensitivity analyses. These omissions limit assessment of how robust any outcome estimate would be, even if a result were available. No estimate can be adjusted for these uncertainties using the registry information alone.

11. 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 entries list 60 participants at risk in the emotionally supportive video group and 58 in the standard video group. In each group, the serious adverse-event count is 0, the other adverse-event count is 0, and the death count is 0. The record lists no serious adverse-event terms.

These are recorded counts for the groups and categories listed. They do not mean that the trial established that no adverse events of any kind occurred, nor do they quantify the uncertainty around the event rates. A zero recorded count is not proof of zero underlying risk; in general, the interpretation of adverse-event counts depends on how events were defined, collected, and followed over time.

The study is described as a one-time visit of up to 60 minutes, but the registry does not provide further detail about safety monitoring or event ascertainment. The safety figures also do not provide information about treatment-choice responses. They should be read as the adverse-event counts recorded in the registry, not as evidence about the primary endpoint or a broader safety conclusion.

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

The study addresses a communication question in a hypothetical setting: whether participants’ stated treatment choices after a simulated surgeon discussion were associated with whether the video included emotionally supportive statements. The randomized, parallel-group design gives a framework for comparing the two video conditions. The intended choice was between total thyroidectomy and lobectomy for a patient portrayed as having low-risk thyroid cancer.

The registry record does not report the choice counts or statistical comparison. It therefore does not show whether the groups’ stated choices differed, which choice was more frequent, or how precise any difference was. It would be inappropriate to interpret the lack of posted results as showing no effect, or as showing that emotional support changed treatment choices.

The hypothetical format also defines the scope of what the endpoint can mean. Participants with benign thyroid nodules who did not need surgery were asked to imagine being the patient in the scenario. A stated choice in that setting is not an observed decision about participants’ own care, a measure of which treatment they ultimately received, or evidence about clinical outcomes. The registry does not report whether responses in a scenario predict choices in clinical practice.

The secondary outcomes could have described participants’ reported confidence, anxiety, fear, perceptions of empathy, and trust, but their results are not reported in the registry record. Thus, no conclusion about those measures is supported either. The most defensible interpretation is limited to the study question and design: the trial was intended to compare responses to two versions of a simulated discussion, but the posted record does not provide the outcome evidence needed to characterize the results.

13. Why This Trial Matters Statistically

This trial is statistically interesting because it turns a communication feature into a randomized comparison. The two groups viewed simulated discussions that differed in whether emotionally supportive statements were included, while the central measure was the participant’s stated treatment choice. Such a design can isolate a specific feature of a communication scenario more directly than an observational comparison, provided the allocation and outcome measurement are implemented and reported clearly.

Its hypothetical choice format is also important. It makes the endpoint a response to a scenario, rather than a record of treatment selected or received. That distinction helps define the estimand—the quantity a study aims to estimate—and prevents a stated preference from being treated as a clinical outcome. The setting and participants further delimit what the result would describe: adults with benign nodules who did not need surgery were asked to imagine a low-risk cancer scenario.

At the same time, statistical interpretation depends on reporting the data and analysis. The registry identifies the randomized design, the two video conditions, and the intended primary measure, but it does not report the choice counts, effect estimate, uncertainty, or detailed analysis plan. The completed status alone cannot answer the comparative question. This illustrates why design information and outcome reporting serve different roles: design explains how a comparison was intended, while results are needed to estimate and assess that comparison.

The registry also lists several secondary outcomes and analyses, making clear why transparent reporting of outcome definitions, analysis populations, missing data, and multiplicity methods matters. Those details are not reported in the registry record, so the strength and precision of any outcome findings cannot be evaluated from it.

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.

A central limitation for interpretation is that the registry record does not report the primary treatment-choice results. No group counts, effect estimate, confidence interval, or p-value are available in the record, so the magnitude and precision of the comparison cannot be assessed. Secondary outcome results are also not reported.

The endpoint is hypothetical: participants were asked to imagine being a patient with low-risk thyroid cancer in a video scenario. The described participants had benign thyroid nodules and did not need surgery. Responses in this setting do not establish what participants would choose for their own care or how an actual clinical consultation would affect treatment decisions. The registry does not report whether the scenario was validated as a representation of real-world decision making.

The enrollment information is not fully reconciled. The registry lists enrollment as 126, whereas the brief summary describes 118 adults to be enrolled. The record does not provide a flow of participants through assignment, video viewing, and endpoint response, so endpoint-specific denominators and any attrition cannot be determined. It also does not report who was masked, how masking was maintained, or the details of allocation procedures.

Finally, the registry lists six outcome measures and eight analyses without detailing the statistical methods, analysis populations, missing-data handling, or multiplicity approach. These reporting gaps prevent a full assessment of the analysis. The record does not describe a protocol sample-size justification; planning illustrations are not evidence of observed power or of a prespecified design rationale.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: The Effect of Surgeon Emotional Support on Treatment Choice for Low-risk Thyroid Cancer — NCT05132478.
• Registry record last updated 2024-04-03; status last verified 2024-04.
• Results first posted 2024-04-03.
• 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.

18. Record Summary

The registry describes a completed, randomized, double-masked, parallel-group hypothetical choice experiment sponsored by the University of Wisconsin, Madison. It compared a simulated surgeon discussion with emotionally supportive statements against a standard simulated discussion without them. Participants were adults with benign thyroid nodules who did not need surgery and were asked to imagine being the patient in a low-risk thyroid cancer scenario.

The primary measure was the treatment choice stated immediately after the video: total thyroidectomy or lobectomy. The registry lists enrollment as 126, while the brief summary describes 118 adults. It lists five secondary outcomes and eight analyses. Serious adverse events, other adverse events, and deaths are recorded as 0 in both groups, with 60 participants at risk in the emotionally supportive group and 58 in the standard group.

The treatment-choice results, secondary results, and detailed statistical methods are not reported in the registry record. The study’s completed status therefore does not permit assessment of the primary comparison.