The Impact of the Attention Training Technique on Attention Control and High Worry: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Impact of the Attention Training Technique on Attention Control and High Worry (NCT03216382), a randomized na study. The primary outcome is Breathing Focus Task -Negative Intrusions.

2. Clinical Question

The study asks whether weekly practice of the Attention Training Technique, compared with a control recording, is associated with changes in attention control, worry, and related cognitive processes among people with high levels of worry. Its primary measure counts negative thought intrusions during a breathing-focus period after a period of worry. The registry record describes measurements across three visits, covering a baseline week and the intervention period.

This is a question about a measured behavioral score over time, not a direct measure of every aspect of worry or attention. The primary endpoint records the number of negative intrusions during a specified task; other outcomes listed in the registry record assess worry, attention, and related cognitive processes using different measures.

3. Trial Design

The registry record describes a randomized, single-masked, parallel-group behavioral trial. Participants were assigned to the Attention Training Technique or a control condition. The study is marked completed, with an enrollment of 95. Its listed condition is excessive worry, and the sponsor is Toronto Metropolitan University. The phase is recorded as not applicable.

The intervention arms shared a similar listening schedule: one recording session in the lab followed by once-daily listening at home for a week. The intervention arm received the Attention Training Technique recording; the control arm received a control recording. The registry record does not report the control recording's content, nor does it establish how closely participants followed the at-home schedule.

The primary measure was planned for three visits over two weeks: Visit 1 at baseline, Visit 2 one week after baseline and before the intervention, and Visit 3 one week after preintervention. The primary measure's described time comparisons are the change from Visit 1 to Visit 2 and the change from Visit 2 to Visit 3. The registry record does not report a single reduced comparison for this multi-timepoint outcome, and numerical results for the primary outcome are not reported in the registry record.

The registry record lists 11 outcome measures and 12 analyses. Listed secondary measures include questionnaires about worry, attention control, metacognition, self-attention, and mindfulness, as well as attention-task measures. The specific analysis procedures for those outcomes are not reported in the registry record. Randomization supports a planned between-arm comparison, but the record does not give allocation details beyond the randomized designation or describe the masking procedure in further detail.

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

Analysis population for the primary outcome, as defined in the registry: Participants were only included on this analyses if they had data for all time points. 3 participants were not included (1 from ATT, 2 from control).

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: Complete case analysis was used, thus only participants who completed the entire intervention were included in the baseline analyses.

6. Primary Endpoint

The registry lists the primary outcome as Breathing Focus Task -Negative Intrusions, measured over Administered three times over the course of two weeks. Changes will be examined from Visit 1 (Baseline) to Visit 2 (Preintervention, 1 week following Baseline) and Visit 2 to Visit 3 (1 week following preintervention)..

The primary endpoint is the Breathing Focus Task -Negative Intrusions score, a mean on a scale. It counts negative thought intrusions reported during a period of focused breathing that follows a period of worry. Scores range from 0-12, and a greater number means more negative thought intrusions. The measure is described as a behavioral measure of attention control over worry.

This task provides a defined setting in which to record a specific response: reported negative thoughts during a breathing-focus period. That makes the outcome narrower than a general assessment of worry. It can be used to examine whether the count changes across the scheduled visits and whether the pattern differs between the randomized arms. The registry record specifies measurements at baseline, one week later before the intervention, and one week after preintervention.

In general, a continuous score can be summarized by its mean, with a standard deviation describing the spread of individual scores around that mean. Those summaries can help describe the observed scores, but they do not by themselves establish why scores changed. The registry record describes the primary outcome as a mean with standard deviation, but numerical means and standard deviations are not reported in the registry record. The primary-outcome analysis excluded three participants who did not have data at all time points: one from the Attention Training Technique arm and two from the control arm.

The endpoint is useful for studying one behavioral aspect of attention control in the task context. It does not, on its own, represent every dimension of worry, attention, or daily functioning.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record describes a randomized, single-masked, parallel-group study with a continuous primary measure. It specifies a mean and standard deviation as the outcome summary and describes two intervals across three visits. The record does not report the statistical model, the primary contrast used to test the research question, or numerical outcome estimates. The explanations below are general statistical context, not a description of an analysis procedure confirmed for this trial.

What does a mean and standard deviation describe?

In general, a mean is an average that gives a compact description of the center of a set of scores. A standard deviation describes how dispersed scores are around that average. A group mean alone does not reveal whether most participants had similar scores or whether scores varied substantially. The standard deviation helps describe that variation, but it is not the same as the uncertainty in the estimated mean. The registry record states that the primary outcome is a mean with standard deviation; the numerical summaries are not reported in the registry record.

What does a between-arm comparison address?

In general, a comparison between randomized arms asks whether the observed outcomes differ between the groups assigned to the two conditions. For a measure collected at multiple visits, the scientific question may concern change over time within each arm, a contrast in change between arms, or an overall pattern across visits. Those are not interchangeable questions. The registry record identifies the two intervals of interest but does not report a single reduced comparison or identify a statistical model for combining the visit data. Numerical between-arm contrasts are not reported in the registry record.

Random assignment is intended to make the arms comparable at the point of assignment, on average, so that outcome differences can be interpreted in relation to assigned condition, subject to the study's conduct and analysis. The registry record does not describe allocation concealment, the masking procedure, or adherence to the listening schedule in further detail. It therefore does not support an assessment of those implementation details.

How should uncertainty be understood?

In general, a confidence interval gives a range of values compatible with the data and the method used to calculate it, under the model's assumptions. A narrower interval indicates more precise estimation than a wider one, but precision is distinct from whether an effect is important. A p-value evaluates the data against a specified null hypothesis under assumptions; it does not quantify the magnitude of an effect. For an interpretable treatment comparison, readers generally need the estimated contrast and an uncertainty measure, not only a p-value. The registry record does not report primary-outcome confidence intervals, p-values, or a numerical contrast.

What does the planning illustration mean?

The registry record describes a sample-size planning illustration based on the observed effect, using a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. It describes the effect to detect as a stated fraction of the observed effect. The number of participants per arm for 80% power or other planning values are not reported in the registry record. Such figures, when presented as planning illustrations, are not observed power and do not show that the study had a particular probability of detecting an effect after the trial was completed. They are conditional calculations under assumptions, rather than trial outcomes or proof of precision.

In general, a planning calculation depends on the target effect, outcome variability, significance level, allocation, and chosen power. Changing those assumptions changes the planning estimate. Because numerical estimates for the observed primary effect and its variability are not reported in the registry record, the planning assumptions cannot be independently interpreted against a reported primary result.

Why can repeated measures require care?

In general, observations from the same participant over time are related rather than independent. An analysis of repeated visits may account for that dependence, but the appropriate method depends on the question, data structure, and assumptions. The record gives three scheduled visits and specifies two changes of interest; it does not say whether the analysis used a repeated-measures model, separate comparisons, or another method. It also does not report how the analysis handled participants with incomplete visit data apart from stating the all-time-points inclusion requirement.

The primary score is a count of reported intrusions bounded by the stated scale from 0-12. In general, count outcomes can have distributions that differ from a symmetric continuous distribution, and scores near the bounds can create additional modeling considerations. The registry record specifies a mean as the outcome parameter but does not report a distributional assessment, model choice, or assumption checks. No particular concern or violation can be concluded without those details and the underlying data.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists 11 outcome measures and 12 analyses. The primary measure is evaluated across three visits, with two change periods described, while the listed secondary measures cover several constructs and instruments. The specific relationship between the listed analyses and outcome measures is not reported in the registry record. A detailed statistical analysis plan, including a prespecified hierarchy of outcomes or comparisons, is not reported in the registry record.

In general, examining multiple outcomes and comparisons creates a multiplicity issue: even when no real effect exists, a larger set of statistical tests creates more opportunities for a result to appear unusual by chance. Researchers may address this by adjusting significance thresholds, using a hierarchical testing strategy, identifying exploratory results, or interpreting findings cautiously. The registry record does not report whether any multiplicity adjustment or other strategy was used. No adjustment should be assumed.

The primary-outcome analysis included participants with data at all time points. Three participants were excluded from that analysis, one from the Attention Training Technique arm and two from the control arm. The reasons for missing measurements, the number with partial data, and any imputation or sensitivity analyses are not reported in the registry record. In general, excluding participants with incomplete repeated measurements can affect the analysis if those with missing data differ systematically from those retained. Whether that concern applies, and its direction or size, cannot be assessed from the registry record.

The record does not report whether all randomized participants were included in an intention-to-treat analysis, whether adherence was analyzed, or whether alternative analysis populations were used. Those details are important for understanding how the randomized comparison was preserved and how missing information was handled.

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 record reports zero serious adverse events and zero other adverse events in the listed risk sets for both arms, and zero deaths. The reported risk set is 34 participants for the Attention Training Technique arm and 44 for the control arm. No serious adverse-event terms are listed.

These counts describe the recorded events among participants in those risk sets. The registry record does not explain why the risk sets differ from the enrollment of 95 or how participants entered the safety accounting. It also does not report further details about event collection, duration of safety follow-up, or whether specific event categories were actively monitored. The zero counts should therefore be read as registry entries for the stated risk sets, not as evidence that no events of any kind occurred outside the recorded categories or observation period.

In general, adverse-event counts depend on who was monitored, what was collected, and for how long. A count of zero does not establish that the underlying risk is zero, especially when the number of observed participants is limited. These safety entries do not provide the missing primary-outcome estimates and do not answer the study's comparative question about negative thought intrusions.

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

The trial addresses a defined statistical question: whether a behavioral measure of negative thought intrusions changed across scheduled visits and whether its pattern differed between randomized arms. The registry record describes the groups, listening schedules, endpoint, and analysis inclusion requirement. It does not report numerical primary-outcome results. Readers therefore cannot determine from the registry record the observed direction, magnitude, or precision of the primary comparison.

The endpoint itself is a task-based count, not a comprehensive measure of worry. A change in this count, if reported, would describe performance on the breathing-focus task under the stated conditions. It would not automatically establish a corresponding change in every form of worry, attention, or everyday functioning. The record lists other measures related to worry and cognition, but their numerical results are not reported in the registry record.

In general, randomization can support a causal comparison of assigned groups when the trial is conducted and analyzed appropriately. Interpretation still depends on the contrast actually estimated, missing data, adherence, outcome measurement, and uncertainty. The registry record does not report enough statistical detail or primary numerical results to evaluate those considerations fully. A completed status indicates that the trial is marked completed; it does not itself establish a result.

The safety entries record zero serious adverse events, zero other adverse events, and zero deaths in the stated risk sets. They should be interpreted within the limits of those recorded groups and the safety information available. They do not demonstrate absence of all possible adverse events.

The central distinction is between an intervention question and evidence answering that question. The study was designed to compare two recordings in people with high worry, but the primary comparative estimates and their uncertainty are not reported in the registry record. The statistical meaning of the observed treatment contrast therefore cannot be determined from these entries.

13. Why This Trial Matters Statistically

This trial is statistically notable because it combines random assignment with repeated measurement of a behavioral outcome in a population described as having high levels of worry. That design raises several useful interpretive questions: what change is being compared, how observations within each participant are handled, and what population is represented by the complete-time-point analysis. The registry record identifies the measurement schedule and exclusions, but does not report the model or numerical estimates needed to resolve those questions.

The primary measure is defined with a bounded score and a specific task context. Statistical interpretation should keep the outcome's meaning tied to that context rather than treating it as a general measure of mental state. The listed secondary outcomes broaden the range of constructs assessed, while also making clear why the analysis plan and treatment of multiple comparisons matter. The record does not report those details.

Another important issue is the difference between planning and observed evidence. The registry record describes a planning illustration based on a fraction of the observed effect, with stated assumptions. Such calculations can help express sample-size requirements under specified conditions, but they do not replace an estimated effect and its uncertainty. They are not observed power.

Finally, the difference between the enrollment and safety risk sets, and the exclusion of three participants from the primary analysis, underscore that the number randomized, the number included in an endpoint analysis, and the number contributing safety data need not be identical. The registry record does not explain all of these differences. Keeping those populations distinct is essential when reading results and judging how broadly they may apply.

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 largest limitation for interpreting the primary question is that numerical primary-outcome results are not reported in the registry record. There are no reported means, standard deviations, treatment contrasts, confidence intervals, or p-values for the primary endpoint. The direction, size, and precision of change therefore cannot be assessed.

The primary outcome has three visits and two described change periods, but the registry record does not identify a single reduced comparison or the statistical model. The analysis requiring data at every time point excluded three participants, one from the Attention Training Technique arm and two from control. Reasons for missing data, the number with partial follow-up, and sensitivity analyses are not reported in the registry record.

The record lists 11 outcome measures and 12 analyses but does not report a detailed analysis plan or how multiplicity was handled. It also does not provide numerical secondary-outcome results. The association between the listed measures and analyses cannot be evaluated from the registry information described.

The trial is described as single-masked, but who was masked and how masking was maintained are not reported in the registry record. The content of the control recording, adherence to the home listening schedule, and further details of allocation procedures are also not reported in the registry record. These omissions limit assessment of how closely the conditions differed and how the study was implemented.

Safety counts are reported for risk sets smaller than the enrollment, without an explanation of the difference or fuller information about event collection and follow-up. Consequently, the recorded zero counts should be interpreted narrowly. These limitations do not establish that the trial was conducted improperly; they identify information not reported in the registry record that would be needed for fuller statistical interpretation.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: The Impact of the Attention Training Technique on Attention Control and High Worry — NCT03216382.
• Registry record last updated 2021-07-02; status last verified 2021-06.
• Results first posted 2021-07-02.
• 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 record describes a completed, randomized, single-masked, parallel-group behavioral trial sponsored by Toronto Metropolitan University, with enrollment of 95. Participants were assigned to the Attention Training Technique recording or a control recording. The primary outcome was the mean number of negative thought intrusions during a breathing-focus task, measured across three visits over two weeks.

The primary analysis included participants with data at all time points and excluded three participants: one from the Attention Training Technique arm and two from control. Numerical results for the primary outcome, the statistical model, and the handling of multiplicity are not reported in the registry record. The registry lists 11 outcome measures and 12 analyses.

For the reported safety risk sets, serious adverse events, other adverse events, and deaths were recorded as zero. The risk sets were 34 for the Attention Training Technique arm and 44 for control. The registry record does not explain their relationship to total enrollment.