Self-Care for Dementia Caregivers: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Self-Care for Dementia Caregivers (NCT05309577), a na na study. The primary outcome is Pre/Post Change in Depressive Symptoms.

2. Clinical Question

3. Trial Design

The registry identifies Self-Care for Dementia Caregivers Using the myRhythmWatch as a behavioral intervention study sponsored by the University of Pittsburgh. Its design is listed as single-group, allocation as NA, and masking as none. The study status is completed. The listed start date is 2023-03-07, and the primary completion date is 2024-12-01. The phase is recorded as NA.

The intervention combined behavioral self-monitoring of sleep and activity with motivational health coaching. Participants wore an Apple Watch to collect sleep-wake rhythm information and received personalized feedback through the myRhythmWatch app. Coaches called participants weekly for up to 6 weeks to support health and sleep goals. The registry also says participants were to help the study team improve the app’s design elements and content.

The planned intervention period is described as up to 6 weeks. The primary endpoint timeframe is also up to 6 weeks. The registry lists an enrollment of 21, while the health outcome analysis population is described separately: 11 of the 15 caregivers completed pre-and post-treatment assessments and were included in that analysis. The registry record does not explain the relationship between the enrollment figure and the caregiver count in the outcome description.

Because the study is single-group and no control group is listed, it does not provide a randomized between-group treatment comparison. A pre/post assessment can describe change over time among participants with both assessments, but by itself it cannot distinguish intervention-related change from other explanations for change. The registry record does not report a protocol sample-size justification, detailed statistical plan, or interim analysis plan.

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 single-arm pilot trial enrolled participants between March 2023 and April 2024 in Pittsburgh, PA.

Overall Study

Analysis population for the primary outcome, as defined in the registry: Eleven of the 15 caregivers completed pre-and post-treatment assessments and were included in the health outcome analysis.

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: Health outcomes were based on data from 15 dementia caregivers

6. Primary Endpoint

The registry lists the primary outcome as Pre/Post Change in Depressive Symptoms, measured over Up to 6 weeks.

The primary endpoint is titled “Pre/Post Change in Depressive Symptoms.” It uses the 9-item Patient Health Questionnaire (PHQ-9), a self-reported questionnaire that assesses depression severity. The registry describes the measure as a score on a scale, with the endpoint parameter specified as a mean and dispersion specified as a standard deviation.

The stated PHQ-9 range is from a minimum score of 0, indicating no impact to patient health, to a maximum score of 27, indicating more severe impacts to patient health. The endpoint is intended to assess depressive symptoms before and after the intervention, over a timeframe of up to 6 weeks. A repeated measure of symptoms can describe whether scores changed among participants who completed both assessments.

The registry describes reducing depressive and insomnia symptoms as the intervention’s goal. The primary endpoint identified in the record concerns depressive symptoms; the record lists 2 outcome measures, but does not give the details of the other measure in the available endpoint information. The observed PHQ-9 mean, standard deviation, pre/post change, and any uncertainty interval are not reported in the registry record. Consequently, the endpoint definition is available, but the size and precision of the observed change are not.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a continuous endpoint summarized as a mean with standard deviation. In general, a mean represents the average of observed scores, while a standard deviation describes how spread out individual scores are around that average. Both are useful for describing a continuous outcome, but neither can be interpreted for this endpoint without the PHQ-9 results. The registry record does not report the pre-treatment or post-treatment mean, the standard deviation, or an estimated change.

What does a pre/post comparison estimate?

In general, a pre/post analysis compares outcome measurements taken at different times. When the same participants contribute both measurements, the analysis can focus on each participant’s change and then summarize those changes. That approach is different from treating the measurements at each time as unrelated groups, because the two scores from the same participant are usually connected. The registry identifies pre-and post-treatment assessments, but does not specify how the observations were analyzed or whether the change was calculated within participants.

The title of the endpoint indicates a pre/post change, and the record says the measure was administered throughout the study. Those details identify the intended comparison, not the statistical procedure used to estimate it. The registry record does not report whether the analysis used a paired test, a model, an adjustment for baseline score, or another method. It also does not provide assumptions used for an analysis or explain how departures from those assumptions were assessed.

Why does uncertainty matter?

In general, an estimated change is not a complete description of evidence. Its uncertainty depends on the data, including the spread of scores and the number of observations included. A confidence interval expresses uncertainty around an estimate under a specified statistical method. A p-value, when used, summarizes how compatible the observed data are with a specified null hypothesis under model assumptions; it is not the probability that the null hypothesis is true. Neither an estimate nor its uncertainty can be reconstructed from the endpoint definition and participant counts alone.

No confidence interval, p-value, test statistic, or numerical effect estimate for the primary endpoint is reported in the registry record. The record lists 0 analyses. That listing does not provide the missing endpoint calculations, and it should not be read as evidence for a particular statistical result. No sponsor analysis is described in the available information, so there is no sponsor estimate to compare with a recalculation.

What does the single-group design allow?

In general, a single-group pre/post design can describe observed changes among participants measured at both times. It does not offer a concurrent control condition to indicate what would have happened over the same period without the intervention. Factors such as natural changes over time, measurement variation, or events outside the intervention can also contribute to a before-and-after difference. This limitation concerns causal interpretation, even if a change estimate is precise.

The study is recorded as single-group, with allocation listed as NA and masking as none. The registry does not identify a randomized comparison or a control arm. The analysis therefore should not be interpreted as a controlled estimate of the intervention’s effect. The record also does not state that the intervention was assigned at random, and no allocation method is reported.

How should planning calculations be read?

In general, sample-size calculations are planning exercises. They describe how many participants per arm a hypothetical study might require under stated assumptions; they do not measure the power achieved by a completed study. The registry’s sample-size assumptions describe a planning illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. The record does not report a protocol-based sample-size justification. No calculated planning values are reported in the registry record, and the stated illustration should not be treated as the study’s design rationale or as observed power.

Those assumptions describe a hypothetical two-arm planning setup, whereas the registered study is single-group. The illustration therefore does not turn the study into a two-arm comparison and does not supply evidence about the endpoint. General planning calculations also depend on the effect and variability used as inputs. Since the numerical endpoint results and calculated planning values are not reported, no such values can be interpreted for this study.

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("Behavioral Intervention")
n   <- c(11)
m   <- c(2.27)
sp  <- c(2.61)
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  Behavioral Intervention  11  2.270  2.610  0.517  4.023

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 2 outcome measures and 0 analyses. The primary outcome information identifies pre/post change in depressive symptoms measured with the PHQ-9. Details for the other outcome measure are not reported in the registry record. No analysis results are listed, and no multiplicity procedure or adjustment is reported. In general, multiplicity refers to the increased chance of a misleading positive finding when many outcomes or tests are examined. Whether and how that concern was addressed cannot be determined from the record.

The endpoint description says that 11 of the 15 caregivers completed pre-and post-treatment assessments and were included in the health outcome analysis. This identifies the population used for that analysis, but does not explain why other caregivers were not included or how their missing measurements were handled. The record does not report whether missing outcomes were imputed, whether any sensitivity analysis was performed, or whether an analysis population beyond those with both assessments was considered.

The registry record does not describe an intention-to-treat analysis, a per-protocol analysis, eligibility rules for analysis beyond completion of both assessments, or a prespecified missing-data strategy. It also does not state whether the analysis plan was finalized before outcome data were examined. These omissions limit assessment of how missing data, outcome selection, and statistical testing may have influenced the reported findings; in this record, the numerical findings themselves are not reported.

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 registry reports safety information separately for Behavioral Intervention (Caregivers) and Behavioral Intervention (PWD). For the caregiver group, 15 were listed as at risk; the record reports 0 serious adverse events, 0 other adverse events, and 0 deaths. For the people-with-dementia group, 6 were listed as at risk; the corresponding reported counts are 0 serious adverse events, 0 other adverse events, and 0 deaths. No top serious-event terms are listed.

These are registry-reported counts for the named groups. Zero reported events means that no events are recorded in those categories in this safety listing; it does not establish that an intervention has no risk. The record does not report the adverse-event definitions, how events were solicited or adjudicated, or the observation period underlying the counts. It also does not provide information about event severity beyond the serious-versus-other categories in the listing. The safety figures should therefore be read descriptively and within the limits of the registry’s reporting.

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

The record describes a behavioral self-monitoring and coaching intervention for dementia caregivers, intended to support regular sleep and activity routines. It identifies depressive symptoms measured with the PHQ-9 as the primary endpoint and reports that 11 of the 15 caregivers completed pre-and post-treatment assessments for the health outcome analysis. This makes the outcome and analysis population clear at a basic level.

The record does not report the PHQ-9 results. It therefore does not show whether scores changed, how large any change was, or how precisely it was estimated. The intervention’s stated goal is not itself evidence that the goal was achieved. Likewise, the study’s completed status does not indicate the direction or strength of an outcome.

Even a reported pre/post difference in this design would describe change over time, not establish that the intervention caused that change. The single-group design has no concurrent control group listed in the registry record. Other influences over the study period cannot be ruled out through a controlled comparison. The record also does not report enough statistical detail to assess the method used, uncertainty around the estimate, or the handling of missing outcomes.

The safety listing records no serious adverse events, other adverse events, or deaths for either listed group. Those counts are limited to what the registry reports and do not establish the absence of all harm. Overall, the registry provides useful details about the intervention and its intended endpoint, but it does not provide the numerical efficacy results needed to judge observed depressive-symptom change.

14. Why This Trial Matters Statistically

This study raises a statistical question common to behavioral interventions: how to interpret symptom measurements taken before and after a program when there is no concurrent comparison group. The endpoint is a self-reported continuous score, and the registry specifies a mean and standard deviation as its summary measures. Understanding the distinction between a description of change and an estimate of causal effect is central to interpreting this design.

The registry also makes the analysis population visible: 11 of the 15 caregivers completed pre-and post-treatment assessments and were included in the health outcome analysis. That detail matters because an outcome estimate based on participants with both assessments may not represent everyone who entered a study if completion is related to outcomes. The record does not explain the reasons for incomplete assessments or report analyses addressing missingness, so the extent of any resulting bias cannot be assessed.

Statistical transparency also matters. A prespecified method, a numerical endpoint estimate, and an uncertainty interval would allow readers to evaluate the magnitude and precision of a result. The registry record does not report these for the primary endpoint. Its stated planning assumptions describe a hypothetical sample-size illustration, not an observed-power calculation and not the protocol rationale for this single-group study.

These issues are not unique to this intervention. They illustrate how design, analysis-population definitions, missing data, and reporting detail shape what can be learned from a clinical study. The registry record describes the intervention and endpoint, but the absence of endpoint results prevents a statistical assessment of depressive-symptom change.

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 principal limitation for interpreting this specific record is that the primary endpoint’s numerical results are not reported. There is no posted pre-treatment or post-treatment PHQ-9 summary, estimated change, standard deviation, confidence interval, or test result. As a result, the direction, magnitude, and precision of the outcome cannot be evaluated.

The single-group design also limits causal inference. The registry lists no control group, and allocation is recorded as NA. Any pre/post change, if reported elsewhere, would not by itself separate intervention-related change from other influences over time. Masking is listed as none; the record does not provide additional detail about how this applied to outcome assessment.

The outcome analysis includes 11 of the 15 caregivers who completed both assessments. Reasons for incomplete assessments, characteristics of participants without paired assessments, and methods for handling missing data are not reported in the registry record. The detailed statistical analysis plan, protocol-based sample-size rationale, multiplicity strategy, and interim analysis plan are also not reported.

The registry lists 2 outcome measures but gives details for the primary depressive-symptom measure in the available information; details of the other measure are not reported in the registry record. Safety counts are available, but event definitions and the observation period are not. These limitations mean the record supports a description of the study setup and reporting, not a complete appraisal of its outcome evidence.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Self-Care for Dementia Caregivers — NCT05309577.
• Registry record last updated 2026-01-23; status last verified 2025-11.
• Results first posted 2026-01-23.
• 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

Self-Care for Dementia Caregivers Using the myRhythmWatch is a completed, single-group behavioral intervention study sponsored by the University of Pittsburgh. The registry lists an enrollment of 21, a start date of 2023-03-07, and a primary completion date of 2024-12-01. The intervention combined sleep and activity self-monitoring through an app and Apple Watch with motivational health coaching for up to 6 weeks.

The primary endpoint was pre/post change in depressive symptoms measured by the PHQ-9, a 9-item self-reported scale ranging from 0 to 27. The health outcome analysis included 11 of the 15 caregivers who completed both assessments. Numerical endpoint results and a detailed analysis plan are not reported in the registry record. Safety listings report zero serious adverse events, zero other adverse events, and zero deaths in each of the caregiver and people-with-dementia groups.