Effect of Emotion Mindsets on Emotion Processing: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effect of Emotion Mindsets on Emotion Processing (NCT03978871), a randomized na study. The primary outcome is Mean Change From Pre to Post Mindset Manipulation on Emotion Mindset Scale (Measures Beliefs About Whether Emotions Are Fixed or Malleable).

2. Clinical Question

The study was designed to examine whether inducing a growth mindset about emotion, compared with a control lesson, was associated with emotion processing at neural, behavioral, and psychological levels. The registry description also sets out a second question: whether neural processing of emotion accounts for an effect of the mindset manipulation on behavioral and psychological processing. These are distinct questions. A difference in a mindset score would address the stated primary endpoint; it would not, by itself, answer the broader questions about neural activity or later emotional functioning.

Participants were to complete a social stressor and functional magnetic resonance imaging session after the lesson. The registry also lists follow-up outcomes concerning emotion mindsets, emotional self-efficacy, and self-reported emotion regulation strategies. However, the posted record does not report numerical results for these outcomes. It therefore does not establish whether the groups differed on the primary measure or any of the broader emotion-processing questions.

3. Trial Design

This was a randomized, double-masked, parallel-group behavioral experiment. The registry lists an enrollment of 163 and a completed study. The study began on 2018-08-27, and primary completion was recorded as 2022-06-27. The phase is listed as NA. The sponsor was the University of Illinois at Urbana-Champaign.

Participants were assigned to one of two conditions: Growth Mindset or Brain Education. The growth mindset arm used persuasive education about emotions, brain development, and teenagers' capacity to learn emotion management. The Brain Education control used neutral education about functions of different parts of the brain. Both groups were described as completing a 25-minute computer-based lesson, followed by a social stressor and a functional magnetic resonance imaging session. The record identifies random allocation and a double-masked design, but does not explain who was masked or how masking was maintained.

The registered primary outcome was mean change from pre- to post-mindset manipulation on an emotion mindset scale. Participants completed a six-item measure of fixed emotion mindset before and after the lessons. The analysis description says that mean change scores were compared across the mindset and control conditions. Other registered measures include emotion mindset and emotional self-efficacy assessments, as well as self-reported emotion regulation strategies at later follow-up points.

The registry record does not report the allocation ratio, the details of the randomization procedure, or the statistical analysis plan. It also does not give a participant flow account or analysis-population definitions. Those details cannot be inferred from the parallel design or the enrollment figure. The study description communicates the intended experimental contrast and the broad sequence of activities, but it is not a substitute for a full protocol or a report of the analyses conducted.

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: One additional participant consented, but then declined participation due to concerns about claustrophobia while in the fMRI machine.

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.

6. Primary Endpoint

The registry lists the primary outcome as Mean Change From Pre to Post Mindset Manipulation on Emotion Mindset Scale (Measures Beliefs About Whether Emotions Are Fixed or Malleable), measured over Pre vs. Post Mindset Manipulation: baseline.

The primary endpoint is mean change in fixed emotion mindset scores from before to after the mindset manipulation. The measure contains six items drawn from the Implicit Theories of Emotion Scale and the Emotion Mindset Scale. Participants rated each item on a 6-point scale, with response options ranging from Strongly Disagree to Strongly Agree. The item means form a score for which higher values represent a more fixed view of emotion. The registry describes a higher score as a worse outcome.

This endpoint is used to assess whether the lesson altered participants' stated beliefs about whether emotions are fixed or malleable. Comparing change between the growth mindset and brain education conditions is more directly relevant to the experimental contrast than looking at post-lesson scores alone, because it accounts for the pre-lesson measurement in the stated outcome definition. The endpoint is a self-report measure of beliefs; it is not a direct measurement of neural activity, behavior during a stressor, or clinical functioning.

The record identifies pre- and post-lesson assessments and says the comparison is between mean change scores in the two conditions. It does not report the group means, standard deviations, between-group estimate, confidence interval, or a test result for this endpoint. The registry's primary outcome is described as involving several categories or time points and is not reduced to a single comparison in the posted results. Consequently, the numerical size and precision of the primary contrast are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a randomized parallel-group experiment comparing two behavioral lessons. In a randomized study, assignment is intended to create groups that differ by the intervention they receive rather than by a systematic selection process. Randomization can support a causal interpretation of a between-group contrast when the study is conducted and analyzed appropriately. It does not guarantee that groups are identical in every characteristic, and the registry record does not describe the randomization sequence, concealment procedures, or analysis details.

What does a change-score comparison mean?

The primary outcome is defined as the mean change from before to after the lesson in a score measuring fixed emotion mindset. A change score represents how an individual measurement changes across the two assessments. The registered comparison is between the mean changes in the Growth Mindset and Brain Education conditions. In general, this contrast asks whether the average pre-to-post movement differs between the randomized groups. It is not the same as asking whether either group changed on its own, and a within-group change alone would not establish a difference attributable to the lesson.

The scale ranges from 1 to 6, and higher scores indicate a more fixed emotion mindset. This direction matters when interpreting a numerical estimate: the meaning of a higher or lower value depends on the stated scale definition. The registry labels a higher score as a worse outcome. No numerical group changes or between-group estimate are reported, so the direction of the observed contrast cannot be interpreted from this record.

Why report variability?

A mean describes the center of a set of measurements, while a standard deviation describes how dispersed individual measurements are around that mean. The primary outcome specifies standard deviation as its dispersion measure. Variability helps readers understand whether participants' scores were relatively alike or spread out. It also contributes to the uncertainty of an estimated group contrast. The registry record does not provide the group means or standard deviations for the primary endpoint.

What would an uncertainty interval add?

In general, a confidence interval gives a range of effect values compatible with the observed data under the chosen statistical model and its assumptions. It communicates precision as well as direction and magnitude. An interval spanning values on both sides of no difference can indicate that the data are compatible with a range of possible contrasts; it should not be read as proof that there is no effect. The posted record does not report a confidence interval for the primary contrast, so its precision cannot be evaluated.

What does the masking description establish?

The design is labeled double-masked. Masking can reduce the influence of expectations on study conduct or outcome assessment, depending on who is masked and how. The registry does not identify the masked parties or describe the masking procedure. The label alone therefore does not show how masking operated in practice or whether it was maintained.

What analysis details are absent?

The record says the primary comparison concerns mean change scores across conditions, but it does not report the statistical test, model specification, adjustment variables, treatment of repeated measures, or method for handling missing observations. It also does not report whether analyses followed randomized assignment or used another analysis population. These details are important because they affect how an estimate is produced and interpreted. They are not recoverable from the outcome title alone.

The record lists 31 outcome measures and 56 analyses. Those counts indicate a broad set of registered measurement and analysis activity, but do not specify the full family of hypotheses, the order of testing, or whether any multiplicity adjustment was used. In general, testing multiple outcomes can increase the chance of finding apparently notable results by chance if the analysis does not account for that multiplicity. No adjustment method or prespecified hierarchy is reported in the registry record.

Planning sample sizes and observed outcomes answer different questions. A planning illustration can show how many participants per arm would be needed under stated assumptions to detect a chosen effect at a chosen power level. It is not an observed result and is not evidence that a trial had a particular probability of finding an effect after completion. No numerical planning illustration is stated in the registry material summarized for this analysis, and the registry does not report a sample-size justification or the assumptions used for the trial's original design.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists a substantial set of outcomes and analyses, including follow-up measures of emotion mindset, emotional self-efficacy, and self-reported emotion regulation strategies. It reports 31 outcome measures and 56 analyses. Such breadth makes it important to know which comparisons were primary, how secondary comparisons were prioritized, and whether any adjustment for multiple testing was used. In general, when many hypotheses are tested, the chance of obtaining at least one apparently notable result by chance can increase. The registry record does not report a multiplicity strategy, a hierarchy of hypotheses, or which analyses were treated as confirmatory.

The posted results do not provide numerical findings for the primary comparison or the listed secondary outcomes. The analysis population is not described, and the record does not say how many participants contributed data to each assessment. Missing-data handling, reasons for missingness, and any sensitivity analyses are not reported in the registry record. Without these details, readers cannot assess whether the available observations represent the randomized groups similarly across outcomes and follow-up assessments.

The record gives an enrollment of 163, but enrollment alone does not identify the number analyzed for a particular outcome. It also does not establish whether every enrolled participant was included in the primary analysis or whether exclusions occurred after randomization. Those details are not reported in the registry record. No assumptions about attrition, imputation, or complete-case analysis should be inferred.

Similarly, the study description does not give a sample-size justification or report interim analyses. Their presence or absence cannot be inferred from the completed status. These omissions limit assessment of the analysis process and the robustness of any eventual findings. They do not change the fact that the posted primary outcome comparison itself is not numerically reported.

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

The record describes a randomized experiment intended to test whether a growth mindset lesson changes fixed emotion mindset scores differently from a brain education control. It also describes a broader interest in neural, behavioral, and psychological emotion processing. These elements establish what the study set out to examine, but they do not establish what the outcomes showed.

Because numerical results for the primary contrast are not reported in the registry record, readers cannot determine the observed direction or size of the difference between groups, or how precisely it was estimated. The same limitation applies to the registered follow-up measures. A completed study status does not fill that reporting gap. It indicates study status, not evidence of an effect.

Even if a numerical change in the fixed emotion mindset score were available, it would need to be interpreted as a change on a self-report measure of beliefs. It would not, by itself, demonstrate changes in brain function, behavior in daily life, emotional development, or clinical outcomes. The stated aims link these domains as questions for investigation, but relationships between them require their own analyses and results.

In general, randomized assignment can strengthen inference about a difference between conditions, but interpretation also depends on the conduct of the trial, the analysis population, missing data, measurement, and uncertainty around estimates. The registry record does not give enough analysis detail to evaluate these features fully. This does not establish that the methods were inadequate; it means the posted record does not report the information needed to judge them.

The adverse-event entries list no events in the recorded categories for either group. That should be read as a description of the registry entries, not as proof that no participant experienced any unwanted event. Details about event collection and reporting are not reported in the registry record. Overall, the information supports a clear account of the study question and design, but not a conclusion about the primary outcome or the broader claims under investigation.

12. Why This Trial Matters Statistically

This trial is statistically interesting because it uses a randomized experimental contrast to examine a specific belief about emotion rather than treating emotion mindset only as an observed characteristic. The comparison between persuasive growth mindset education and neutral brain education gives the study a defined intervention and control condition. The intended primary contrast—change in fixed emotion mindset scores across conditions—also connects the manipulation to a measured belief outcome.

The study description reaches beyond a single questionnaire. It includes a social stressor, functional magnetic resonance imaging, and planned assessments of emotional self-efficacy and emotion regulation. That range reflects a multilevel research question: whether an intervention is associated with neural, behavioral, and psychological processing, and whether neural processing helps account for other outcomes. Each link requires clearly specified comparisons and reported estimates; a broad rationale alone cannot establish those links.

For statistical interpretation, the distinction between a stated hypothesis and an observed result is central. The registry gives substantial design context, including randomized allocation, double masking, parallel groups, and enrollment of 163. Yet the primary estimate and its uncertainty are not reported. That makes the study a useful example of why design information and outcome reporting have different roles. A well-defined question cannot be answered quantitatively without the corresponding results.

The number of registered outcomes and analyses also highlights the importance of transparent analysis planning. When many outcomes are considered, readers need information about prioritization, multiplicity, missing data, and analysis populations to understand how findings should be weighed. The registry does not report those details. These are reporting gaps, not proof of a particular analytic choice. Together, the record illustrates how careful interpretation depends both on the experimental design and on complete reporting of estimates and methods.

13. 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 trial from the registry record is that numerical results for the primary outcome are not reported. Group-specific changes, a between-group estimate, variability, and an uncertainty interval are absent. The registry notes that the primary outcome involves several categories or time points and is not reduced to one comparison in the posted results. As a result, the central contrast cannot be quantified or assessed for precision.

Further details needed to evaluate the design and analysis are also not reported in the registry record. These include the allocation ratio, randomization procedures, the identities of those masked, and how masking was maintained. The record does not define the analysis population, explain missing-data methods, or describe whether covariates or repeated measures were modeled. It does not report a statistical analysis plan, sample-size justification, or interim analyses.

The listed 31 outcome measures and 56 analyses raise the importance of understanding how outcomes and comparisons were prioritized, but the record does not describe a multiplicity approach. It also does not provide participant counts contributing to each outcome or follow-up assessment. Enrollment of 163 cannot substitute for outcome-specific analysis counts.

The primary endpoint is a self-report scale of fixed emotion mindset. It addresses reported beliefs, rather than directly measuring all the neural, behavioral, or psychological processes named in the study aims. The registry describes an imaging session and a social stressor, but does not report their results. Finally, the adverse-event record contains zero counts in the listed categories without further information about collection or completeness. These limitations concern what the registry reports; they do not establish that unreported procedures or analyses were not conducted.

14. Related Tutorials

15. Related Statistical Calculators

16. Sources

• ClinicalTrials.gov: Effect of Emotion Mindsets on Emotion Processing — NCT03978871.
• Registry record last updated 2026-05-19; status last verified 2025-03.
• Results first posted 2025-04-17.
• 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.

17. Record Summary

NCT03978871, titled Effect of Emotion Mindsets on Emotion Processing, is a completed randomized, double-masked, parallel-group behavioral study sponsored by the University of Illinois at Urbana-Champaign. Enrollment was 163. The study began on 2018-08-27, and primary completion was 2022-06-27. The phase is listed as NA.

Adolescent girls were the population of interest. The study compared a growth mindset lesson about emotions with neutral brain education. The planned sequence included a 25-minute computer-based lesson, a social stressor, and a functional magnetic resonance imaging session. The primary measure was mean change in fixed emotion mindset scores from before to after the lesson, with higher scores representing a more fixed mindset.

The record also lists follow-up measures of emotion mindset, emotional self-efficacy, and emotion regulation strategies. It records 31 outcome measures and 56 analyses. Numerical results for the primary contrast and the listed secondary outcomes are not reported in the registry record. The adverse-event entries list 0 serious events, 0 other events, and 0 deaths for each group.