Neuromodulation for Comorbid Hoarding Disorder and Depression: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Neuromodulation for Comorbid Hoarding Disorder and Depression (NCT05985356), a na na study. The primary outcome is Saving Inventory -- Revised.

2. Clinical Question

3. Trial Design

The registry record identifies NCT05985356 as a completed study titled “Neuromodulation for Comorbid Hoarding Disorder and Depression.” The listed sponsor is University of California, San Diego. The recorded start date is 2023-08-28, and the primary completion date is 2025-04-30. Enrollment is reported as 14. The phase and allocation entries are listed as NA; the model is single group, and masking is none. These design features describe a study without a randomized, masked comparison between treatment groups.

The intervention is iTBS, a form of transcranial magnetic stimulation directed at the left dorsolateral prefrontal cortex. The study summary states that its main goal is evaluating treatment for depression among people with depression and chronic hoarding disorder. It also describes interest in hoarding symptoms, cognitive performance, brain-region connectivity, and factors that could enhance or hinder treatment. The registry lists Hoarding Rating Scale, Patient Health Questionnaire - 9, Neuropsychological Global Deficit Score, and Resting State Functional Connectivity among the secondary outcomes.

The primary outcome is the Saving Inventory -- Revised, measured as a score on a scale, with change from baseline to 8 weeks as the timeframe. The registry describes 3 participants as not assigned to treatment because baseline assessment was not completed or study criteria were not met. It does not describe the analysis population beyond that note. Although 6 outcome measures are recorded, the analysis count is 0. The statistical analysis plan, detailed intervention schedule, and any explanation of the enrollment target are not reported in the registry record.

Because this is a single-group study, there is no concurrent control group in the registered design. A before-and-after change can indicate how scores differed over the study period among participants with measurements, but it is not equivalent to a randomized treatment-versus-control contrast. Other influences over time, selection into the observed analysis group, and measurement variability remain possible considerations.

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: This was a single group study. Participants completed baseline assessment and then began treatment.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: 3 participants not assigned to treatment due to not completing baseline assessment (1) or not meeting study criteria (2)

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: 3 participants not assigned to treatment due to not completing baseline assessment (1) or not meeting study criteria (2)

6. Primary Endpoint

The registry lists the primary outcome as Saving Inventory -- Revised, measured over change from baseline to 8 weeks.

The primary endpoint is change from baseline to 8 weeks in the Saving Inventory -- Revised score. The registry describes this instrument as measuring hoarding symptom severity. Its scale ranges from a minimum of 0 to a maximum of 92, and higher scores indicate more severe hoarding symptoms. The listed summary measure is the mean, with standard deviation as the measure of dispersion.

In general, a continuous symptom score can retain gradations in severity rather than reducing each participant’s experience to a simple yes-or-no category. A mean change can describe the average direction and size of score change for the participants included in the analysis. The standard deviation describes how dispersed individual scores are around the mean; it is not the same as the uncertainty in the estimated mean change.

This endpoint is relevant to the study because hoarding symptoms are a central part of the comorbid condition under investigation. However, the study’s stated primary goal concerns depression, whereas the registered primary endpoint is a hoarding measure. The registry lists a depression questionnaire as a secondary outcome, but does not report results for either measure. Therefore, the record does not establish the observed direction, magnitude, or precision of change on the primary endpoint.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a mean change describe?

The primary outcome is continuous and summarized using a mean and standard deviation. In general, a mean change describes the average difference between participants’ baseline and follow-up scores, provided the analysis defines the change in that way and includes the relevant measurements. The registry names the timeframe as change from baseline to 8 weeks, but does not report the calculated mean change. It also does not describe the precise computational or modeling procedure used to estimate it.

The mean gives a measure of the center of the observed changes. The standard deviation describes the spread of individual values around that center. A small standard deviation would indicate that the observed values are relatively clustered, while a larger one would indicate more variability; neither situation, by itself, establishes how precisely the mean has been estimated. Precision also depends on the amount and pattern of available information. Those observed quantities are not reported for the primary endpoint.

How would uncertainty be assessed?

In general, a confidence interval gives a range of values compatible with the data and the assumptions of a statistical procedure. A narrower interval indicates greater statistical precision under those assumptions; a wider interval indicates less precision. It is not a range containing a guaranteed proportion of individual participant scores, and it does not account automatically for bias or limitations in the study design. The registry record does not report a confidence interval for the primary outcome.

A hypothesis test can assess how compatible observed data are with a specified null model. Its p-value is not the probability that the null hypothesis is true, nor is it a measure of clinical importance. Interpretation should consider the estimated effect and its uncertainty, not a threshold alone. The record reports no primary-outcome test statistic or p-value, so statistical significance cannot be assessed from the registry results described.

What does a single-group change estimate mean?

In general, a within-group before-and-after estimate answers a different question from a between-group treatment contrast. It describes how the measured outcome changed over time in the analyzed group. A randomized concurrent comparator can help account for changes that would have occurred without the intervention, if the trial is appropriately designed and analyzed. This study is registered as single group, with allocation listed as NA, so the record does not support a randomized comparison of iTBS against a control condition.

A change from baseline can still be informative as a description of the observed course in the participants measured. However, it does not by itself establish that the intervention caused the change. Time-related changes, other care, participant expectations, measurement variation, and incomplete follow-up may all affect a before-and-after result. The registry does not report the outcome estimates needed even for a descriptive account of the change.

Why does the analysis population matter?

An analysis population defines which participants contribute to an outcome estimate. Different choices can produce estimates with different interpretations, particularly when some people do not start treatment, do not complete assessments, or lack follow-up measurements. The primary outcome description notes that 3 participants were not assigned to treatment because baseline assessment was not completed or study criteria were not met. It does not report the number included in the primary endpoint analysis, how eligibility and treatment status were handled in that analysis, or how missing scores were addressed.

How should sample-size illustrations be read?

The sample-size material is characterized as a planning illustration computed from the observed effect, rather than the trial’s own design. It assumes a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. These assumptions concern a hypothetical planning exercise and do not describe the registered single-group design. The illustrations are not observed power, do not establish that the study was adequately powered, and cannot replace an outcome estimate or uncertainty interval. The registry record does not report the rationale used to set enrollment or a sample-size justification for the trial itself.

In general, sample-size planning depends on the target effect, outcome variability, statistical model, allocation, error threshold, and desired probability of detecting the target effect under the assumed model. Changing those assumptions changes the planning result. When the observed effect is used to construct an illustration, the result is particularly dependent on that effect estimate and should not be interpreted as independent evidence about the study’s ability to detect a clinically meaningful effect. No such independent design justification is reported in the registry record.

Why can variability differ from a simple normal model?

In general, a normal approximation is a mathematical simplification that may be used for planning or inference. When measurements have unusual distributions, influential extreme values, or variability that differs across conditions, methods that account for those features may be more appropriate. Over-dispersion, in general, means that observed variability is greater than a model expects; ignoring it can make uncertainty look too small. These are general statistical considerations, not claims about the distribution of scores in this study. The registry record does not describe a distributional assessment or an analysis method for the primary outcome.

Because the record reports no outcome estimates and no analyses, readers cannot verify model assumptions, compare adjusted and unadjusted results, or assess whether any sensitivity analyses were performed. The statistical analysis plan and details of any such checks are not reported in the registry record.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("iTBS")
n   <- c(11)
m   <- c(50.6)
sp  <- c(16.6)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  iTBS  11  50.600  16.600  39.448  61.752

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 6 outcome measures and names several secondary outcomes, including hoarding, depression, cognitive performance, and resting-state functional connectivity measures. When a study examines multiple outcomes or multiple analyses, there is a general risk that at least one result may appear noteworthy by chance. Statistical plans may address this through prespecified primary outcomes, a hierarchy of tests, adjusted significance thresholds, or cautious interpretation. The registry record does not report a multiplicity strategy, a hierarchy among outcomes, or a statistical analysis plan. It also reports 0 analyses, so no outcome-specific inferential results are available for evaluating how multiplicity was handled.

Missing data are relevant because the primary outcome requires baseline and follow-up measurement to describe change over the stated timeframe. The registry notes that 3 participants were not assigned to treatment because baseline assessment was not completed or study criteria were not met. It does not report whether additional participants lacked follow-up data, the reasons for any missing measurements, or the method used to address missingness. No imputation approach, complete-case rule, or sensitivity analysis is reported in the registry record.

In general, missing-data methods rely on assumptions about why measurements are absent. If people with missing scores differ from those with observed scores, an analysis limited to available measurements can describe a selected subset rather than all enrolled participants. Imputation can also depend on assumptions and does not automatically remove bias. The record does not supply enough detail to determine which assumptions or methods, if any, were used.

The primary endpoint analysis population is not fully described. The safety record lists a separate group at risk, but that denominator should not be assumed to define the primary outcome population. Enrollment, treatment exposure, safety follow-up, and availability of endpoint measurements are distinct aspects of study accounting. Their relationship is not reported in the registry record.

12. 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 adverse-event record lists the iTBS group with 11 participants at risk for serious adverse events, 0 participants affected by serious adverse events, 11 at risk for other adverse events, and 0 affected by other adverse events. Deaths are recorded as 0. No serious adverse-event terms are listed. These figures describe what the registry records for the reported safety group; they do not provide a detailed account of event collection, observation time, or the criteria used to classify events.

In general, a count of zero observed events does not prove that the underlying risk is zero. It means no events were recorded among the participants included in that safety denominator during the period and under the ascertainment procedures used. The precision of a risk estimate depends on the amount of exposure and the completeness of event follow-up, details that are not reported in the registry record. A zero count therefore should not be read as evidence that an intervention is risk-free.

The safety denominator is not necessarily the same as the population analyzed for the primary symptom endpoint. The registry separately notes that 3 participants were not assigned to treatment for baseline or eligibility reasons, while it lists 11 at risk in the safety group. The record does not explain the full relationship between those figures and the primary outcome analysis population. These adverse-event counts should be interpreted as descriptive registry data rather than as a comparison against another treatment or control group.

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

The registry record describes a completed single-group study of iTBS targeting the left dorsolateral prefrontal cortex in people with depression and chronic hoarding disorder. It identifies the Saving Inventory -- Revised change from baseline to 8 weeks as the primary endpoint, and the measure is defined as a scale of hoarding symptom severity on which higher scores indicate more severe symptoms. This information clarifies the registered question and the outcome chosen to represent hoarding symptoms.

The record does not report the primary endpoint result, its uncertainty, or a statistical test. It therefore does not establish whether scores changed, the direction or magnitude of any change, or how precisely an estimate was determined. The completed status does not imply that results are available in this record. The listed secondary outcomes likewise do not have reported numerical results in the information described.

The design also limits what an observed change could establish. In general, a single-group before-and-after study can describe change over time, but without a concurrent control group it cannot separate intervention effects from other possible explanations for change. The registry does not describe a randomized comparator, and allocation is listed as NA. This prevents a like-for-like treatment contrast in the registered design.

The study’s stated primary goal is to evaluate iTBS for depression, but the registered primary endpoint measures hoarding symptoms. The depression questionnaire appears among the secondary outcomes. The record does not report results for either endpoint, so it cannot support a conclusion about the observed depression or hoarding response. Nor does the record provide results sufficient to judge changes in cognition or connectivity.

These limits concern what can be concluded from the registry record, not whether the intervention is effective or ineffective. The record provides design and safety-count information, while the main outcome estimates, analysis methods, missing-data handling, and multiplicity approach are not reported in the registry record. Any interpretation should remain within those boundaries.

14. Why This Trial Matters Statistically

This study is statistically notable for the relationship between its stated clinical aim and its registered primary endpoint. The stated primary goal concerns depression among people who also have chronic hoarding disorder, while the named primary measure is the Saving Inventory -- Revised, which assesses hoarding symptom severity. Depression is included among the secondary outcome areas through the Patient Health Questionnaire - 9. This makes it important to distinguish the endpoint that anchors the registered primary outcome from the broader clinical aims.

The single-group design also makes the interpretation of change central. In general, a before-and-after measure can characterize the course of scores in a treated group, but it does not provide the same evidence as a randomized comparison. Without a concurrent control, changes cannot be cleanly attributed to the intervention rather than to time, other care, expectations, or other influences. Recognizing this design feature prevents a descriptive change from being mistaken for a causal treatment effect.

The record further illustrates why outcome reporting and analysis detail matter. It lists 6 outcome measures but reports 0 analyses, and it does not report the primary outcome estimate, uncertainty, or missing-data approach. Without those details, readers cannot assess magnitude, precision, consistency across outcomes, or the assumptions underlying an analysis. A completed status and a specified endpoint are not substitutes for posted results.

Finally, planning illustrations based on an observed effect should be separated from prospective design justification and from observed power. The registry characterizes its illustrations as planning calculations, not as the trial’s own design. They cannot establish the strength of evidence or compensate for absent outcome results. The statistical value of the record is therefore in clarifying the design, endpoint definition, and reporting gaps, rather than in quantifying an intervention effect.

15. 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 primary limitation for interpreting this specific study is that the registry record does not report the primary outcome result. There is no mean change, standard deviation, confidence interval, or test result described. Without those statistics, the direction, magnitude, and precision of the registered endpoint cannot be evaluated. The record also reports 0 analyses, leaving no inferential results to interpret.

The single-group design has no registered concurrent control comparison. As a result, even if before-and-after estimates were available, the design would not isolate the intervention’s contribution from other changes over time. The record lists no masking and no randomized allocation. These features are relevant to interpretation, but the registry does not provide enough information to assess treatment delivery, participant expectations, or any other potential sources of bias in detail.

The registry notes that 3 participants were not assigned to treatment because baseline assessment was not completed or study criteria were not met. It does not report the full endpoint analysis population, whether further measurements were missing, or how missing data were handled. Consequently, the representativeness of any potential primary outcome estimate cannot be assessed from this record. The safety denominator is reported separately and should not be treated as a substitute for endpoint accounting.

The study summary describes depression as the main treatment target, whereas the registered primary endpoint is a hoarding symptom scale. Depression is included as a secondary outcome, but its result is not reported. This difference between the broad aim and the named primary endpoint should be considered when deciding which clinical question the registered outcome could directly address.

Additional limitations include the absence of a reported statistical analysis plan, multiplicity strategy, sample-size justification, and detailed intervention schedule. The planning illustrations are not the trial’s own design and do not establish observed power. These reporting gaps restrict reproducibility and prevent a fuller assessment of the analysis.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Neuromodulation for Comorbid Hoarding Disorder and Depression — NCT05985356.
• Registry record last updated 2026-06-17; status last verified 2026-05.
• Results first posted 2026-06-17.
• 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.

19. Record Summary

NCT05985356 is recorded as completed and uses a single-group design with no masking. Enrollment is listed as 14, and the intervention is iTBS targeting the left dorsolateral prefrontal cortex. The primary endpoint is change from baseline to 8 weeks on the Saving Inventory -- Revised, a hoarding symptom severity measure for which higher scores indicate greater severity.

The registry reports 3 participants not assigned to treatment because baseline assessment was not completed or study criteria were not met. Its safety entry lists 11 participants at risk in the iTBS group, with 0 affected by serious adverse events, 0 affected by other adverse events, and 0 deaths. These safety counts are descriptive and do not establish zero underlying risk.

The record lists 6 outcome measures and 0 analyses. It does not report the primary outcome estimate, uncertainty, statistical analysis plan, missing-data handling, or multiplicity approach. The single-group design does not provide a randomized control comparison, and the registered results therefore do not quantify a causal treatment effect.