Problem Adaptation Therapy for Mild Cognitive Impairment and Depression: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Problem Adaptation Therapy for Mild Cognitive Impairment and Depression (NCT03043573), a randomized na study. The primary outcome is Change in Global Cognition Assessed by RBANS.

2. Clinical Question

The clinical question is whether the two behavioral approaches differ in their measured cognitive, affective, and functioning outcomes among the study population. The primary focus is global cognition, not a diagnosis or a single clinical event. The record also lists changes in disability function, depression, episodic memory, and executive function as secondary outcomes. It reports six outcome measures overall, although the available list names four secondary outcomes in addition to the primary outcome.

The comparison is between PATH-MCI and an active supportive-therapy comparator, rather than between therapy and no treatment. That distinction matters for interpretation: a comparison between two structured behavioral approaches addresses their relative outcomes under the study conditions, not the effect of receiving any therapy versus receiving none. The registry description does not establish what participants experienced beyond the arm descriptions, nor does it report enough outcome data to judge the size or precision of any between-arm difference. The primary result therefore cannot be characterized as favoring either approach from the registry record alone.

3. Trial Design

The registry describes a randomized, single-masked, parallel study comparing PATH-MCI with Supportive Therapy. Both interventions are classified as behavioral. Enrollment is recorded as 80. The study is listed as completed, with a start date of 2017-07-01 and a primary completion date of 2024-09-19. The phase is listed as NA, which is the registry entry; no further phase interpretation is reported in the registry record.

In a parallel design, participants are assigned to one of the study arms and the arms are compared over the study’s assessments. Random allocation is reported, but details of how the allocation sequence was generated, concealed, or implemented are not reported in the registry record. The record identifies the study as single-masked but does not say which people were masked. It also does not describe how masking was maintained or whether it was assessed.

PATH-MCI is described as using emotion-regulation techniques and environmental adaptation tools, with examples including notes, checklists, and calendars, as well as the WellPATH app. The intervention description is incomplete in the registry record. Supportive Therapy is described as facilitating affect expression, conveying understanding and empathy, and highlighting positive experiences; its manual is intended to standardize nonspecific therapeutic factors. Detailed information on treatment duration, session frequency, therapist training, treatment fidelity, and adherence is not reported in the registry record.

The primary outcome is measured at baseline, 12, 24, and 52 weeks. The record notes that the pandemic and some participants’ inability to complete assessment measures led to discrepancies between the numbers randomized and analyzed at different time points. The numbers analyzed at each time point and the methods used to address incomplete assessments are not reported in the registry record. Although the study is marked completed, the registry information does not include numerical primary-outcome results.

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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The study was affected by the pandemic and by the inability of certain participants to complete assessment measures during the study. Therefore, there is a discrepancy between the numbers of randomized and the numbers of analyzed participants at different time points.

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 Change in Global Cognition Assessed by RBANS, measured over Baseline, 12, 24, and 52 Weeks.

The primary endpoint is change in global cognition, assessed with the Repeatable Battery for the Assessment of Neuropsychological Status total score, or RBANS. The measure combines five cognitive domain index scores: Immediate Memory, Visuospatial/Constructional, Language, Attention, and Delayed Memory. The total score is described as a simple sum of those domain index scores, with raw scores converted based on the subject’s age and a RBANS scoring manual. The listed score range is 200 to 800, and higher scores indicate better functionality.

Global cognition is used as the primary measure because it captures performance across several cognitive domains in a single outcome. This provides a broad summary rather than isolating one specific domain. The registry identifies the mean and standard deviation as the summary measure and gives assessment times of baseline, 12, 24, and 52 weeks. Repeated assessment can describe the course of scores over time, but interpretation depends on the analysis comparing the arms and accounting for measurements from the same participant.

The endpoint description establishes what was intended to be measured; it does not establish what the study found. Numerical scores, between-arm estimates, confidence intervals, and tests of the primary outcome are not reported in the registry record. The clinical meaning of any observed change also cannot be judged from the outcome definition alone. In particular, the record does not provide a threshold for interpreting a change as important to participants or clinicians.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies the outcome summary as a mean with a standard deviation. The mean describes the average score in a group, while the standard deviation describes how dispersed individual scores are around that average. These summaries help characterize the observed scores, but they do not by themselves estimate the uncertainty in the difference between arms. A standard error or confidence interval for the contrast would be needed to describe that uncertainty directly.

For repeated measurements, the same participant can contribute scores at baseline and later assessments. Those observations are related rather than independent. A statistical analysis should account for that within-participant relationship if it models the measurements jointly. Alternatively, an analysis might define a particular follow-up change or contrast. The registry record does not report which approach was used, the model specification, or how the comparison across assessment times was estimated.

A change score compares a participant’s follow-up measurement with that participant’s baseline measurement. An analysis of change can be presented as a group average or as a contrast between groups. Another approach can compare follow-up scores while accounting for baseline scores. These approaches can answer related but not identical statistical questions, and their estimates may differ. The registry record does not identify the exact estimand or analysis method for the primary outcome, so no particular approach should be attributed to this study.

Random allocation supports a comparison between groups by reducing systematic differences in baseline characteristics on average, when implemented as intended. It does not ensure that the realized groups are identical, and it does not remove the need to report baseline information, follow-up completeness, and the analysis population. The registry reports random allocation but does not report sequence generation, allocation concealment, baseline outcome summaries, or a detailed account of participants included in each analysis.

A confidence interval is a way to express uncertainty around an estimated effect under the assumptions of the statistical procedure. A narrower interval indicates greater precision than a wider interval, while the interval’s location indicates which effect values are compatible with the observed data and model. Statistical significance and clinical importance are different considerations: statistical evidence concerns compatibility with a null hypothesis, while clinical importance concerns whether an effect is meaningful in context. The primary-outcome estimates and their intervals are not reported in the registry record, so neither precision nor clinical importance can be assessed.

Dispersion also matters when analyzing continuous outcomes. If variability is greater than a model assumes, standard errors and confidence intervals based on that model may be too optimistic. In general, over-dispersion means the data vary more than expected under a specified model, and methods that account for it can change estimated uncertainty. The endpoint is summarized using a mean and standard deviation, but the record does not report a variance assessment or an approach to over-dispersion. It would therefore be inappropriate to claim that the study tested or corrected for it.

The record states that sample-size illustrations use a two-sided significance level of 0.05, equal allocation between the arms, and a normal approximation. The target effect in those illustrations is a stated fraction of the observed effect. Such calculations are planning illustrations based on an observed effect, not a report of the study’s original design justification and not evidence of observed power. The record does not report the trial’s own sample-size justification or the effect assumptions used in its original planning. No specific illustration value should be interpreted as an observed trial result.

In general, a sample-size calculation estimates how many participants would be needed to detect a specified effect under stated assumptions and a chosen error rate. Its answer depends on the assumed effect, outcome variability, allocation, and analysis. If the effect used for planning is based on an observed estimate, the illustration inherits uncertainty in that estimate. It cannot establish that the completed study had a particular probability of detecting an effect, especially without the original design assumptions and the actual analysis details.

The registry reports 32 analyses. A count of analyses is not itself a description of the statistical method. The record does not state which models were fitted, which covariates were included, whether estimates were adjusted, how outliers or protocol deviations were handled, or whether sensitivity analyses were performed. These details are necessary to reproduce the analysis and to judge whether the reported uncertainty reflects the study design.

For the safety data, counts are reported for participants at risk and participants affected by serious and other adverse events, alongside deaths. These are descriptive summaries. A formal comparison of event risks would require a defined analysis and careful interpretation of sparse counts, follow-up, and event attribution. The registry record does not report such a comparative safety model. The event counts should therefore be read as reported counts, not as a modeled treatment effect.

10. Multiplicity, Missing Data and Analysis Populations

The record lists six outcome measures and 32 analyses, but does not explain how those analyses relate to the outcome hierarchy or to one another. It does not report a prespecified statistical analysis plan, identify which analyses were confirmatory beyond naming the primary outcome, or state whether any adjustment was made for multiple comparisons. When many outcomes, time points, or analyses are considered, the chance of finding an apparently notable result can increase. General methods for addressing multiplicity include defining a hierarchy of outcomes or adjusting the testing procedure, but the registry record does not say whether such methods were used in this study.

The primary outcome has assessments at baseline, 12, 24, and 52 weeks. Multiple assessment times may be addressed through a single model or through separate comparisons; these choices affect the interpretation and multiplicity of the findings. The exact primary contrast and handling of repeated measurements are not reported in the registry record. The record’s indication that the outcome has several time points is also why it is not reduced to a single comparison.

Missing data are a specific concern. The registry says that the pandemic and some participants’ inability to complete assessment measures caused discrepancies between the numbers randomized and the numbers analyzed at different time points. It does not report the number analyzed at each assessment, reasons for missingness by arm, or whether missing data were handled with imputation, likelihood-based methods, or another approach. It also does not report whether sensitivity analyses examined how conclusions might change under different assumptions about missing outcomes.

Without those details, it is not possible to determine whether the analyzed participants represent everyone randomized or whether the analysis follows an intention-to-treat principle. The registry’s note identifies an issue that matters for interpretation; it does not specify the analysis population or resolve the potential impact of missingness. The primary comparison therefore cannot be evaluated for robustness to missing data or multiplicity from the registry record.

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.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: major depressive episode (2.6%), masectomy (2.6%), breast reconstruction (2.6%), tachycardia (2.6%), back pain (2.6%).

For PATH-MCI, the registry lists 39 participants at risk for serious adverse events and 5 affected; it lists 39 at risk for other adverse events and 4 affected. For Supportive Therapy, it lists 41 participants at risk for serious adverse events and 1 affected; it lists 41 at risk for other adverse events and 6 affected. Deaths are listed as 0 in each arm. These are counts as recorded, not estimates adjusted for follow-up or other participant characteristics.

The registry also lists serious-event terms with percentages: Major Depressive Episode, 2.6%; Masectomy, 2.6%; Breast Reconstruction, 2.6%; Tachycardia, 2.6%; Back Pain, 2.6%; and Chest Pain, 2.4%. The record excerpt does not specify the arm associated with each term or provide the full event-level context. The terms and percentages should not be used to infer treatment causation.

Adverse-event counts are descriptive and do not alone show whether an event was caused by an intervention. Differences in the numbers affected can also depend on follow-up duration, event definitions, and reporting practices. The registry record does not report a formal comparative safety analysis, attribution judgments, or detailed timing for the events. These figures should therefore be read as reported safety information, distinct from an estimate of comparative risk.

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

The registry record establishes that a randomized, parallel study compared two behavioral therapies and identified RBANS global cognition as its primary outcome. It also describes the intended assessment schedule, the broad features of each intervention, and counts of participants affected by serious and other adverse events. These details help define the study question and the kind of evidence the study was designed to produce.

The record does not report numerical primary-outcome results, so it cannot support a conclusion about the direction or size of the cognitive outcome difference between PATH-MCI and Supportive Therapy. It also does not report confidence intervals or p-values for that endpoint. The absence of these results in the registry record should not be mistaken for evidence of no difference, or for evidence that one therapy performed better. It means the comparative primary outcome cannot be assessed from the information recorded.

Similarly, the event counts do not establish that either intervention caused or prevented an adverse event. They are counts in the listed groups, with no reported formal comparison or event attribution details. They do not answer the primary cognitive question and should not be combined with it as if they were a single measure of benefit and harm.

The record’s note about incomplete assessments also matters. At different time points, analyzed participant numbers differed from randomized numbers because of pandemic effects and inability to complete assessments. Without counts by time and arm, an analysis description, and missing-data sensitivity analyses, it is not possible to judge whether missing observations materially changed the estimated outcome. Likewise, the reported count of analyses does not reveal whether multiplicity was addressed.

Accordingly, the available information supports a description of the trial’s design and reporting limitations, rather than a treatment recommendation or an efficacy conclusion. Interpretation of whether the therapies differed would require the primary estimates, their uncertainty, the analysis population, and enough methodological detail to assess missing data and multiplicity. Those items are not reported in the registry record.

13. Why This Trial Matters Statistically

This study raises several statistical issues that are common in clinical research. Its primary outcome is continuous and measured repeatedly, so interpretation depends on how the analysis defines change and accounts for correlated observations within a participant. Reporting only an endpoint definition is not enough to reconstruct the treatment contrast: the model, target comparison, and uncertainty estimates are also needed.

The registry explicitly notes differing numbers of randomized and analyzed participants at different time points. That makes transparent reporting of follow-up completeness and missing-data methods especially important. Missing assessments can reduce precision, and under some conditions can also bias a comparison. Without arm-specific counts and a stated method, readers cannot distinguish those possibilities or assess the sensitivity of conclusions to the missingness assumptions.

The record also reports six outcome measures and 32 analyses. This illustrates why a clear analysis plan and outcome hierarchy matter. Readers need to know which comparison was primary, how time points and secondary measures were handled, and whether multiplicity was addressed. A large analysis count alone does not indicate that the results are unreliable, but it does make the analysis structure important to transparent interpretation.

Finally, the record has a defined intervention comparison and safety counts but lacks the numerical primary-outcome findings in the registry record. This highlights a basic distinction between trial registration and result interpretation: design details explain what was intended, whereas estimates and uncertainty are needed to understand what the measured outcomes show. Statistical interpretation should stay within that boundary.

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 primary limitation for interpreting this study from the registry record is the absence of numerical results for the primary outcome. Although RBANS global cognition and its assessment schedule are described, the record does not include group summaries, between-arm estimates, confidence intervals, or hypothesis-test results. The relative cognitive outcomes of PATH-MCI and Supportive Therapy therefore cannot be evaluated from the reported information.

The record notes that the pandemic and participants’ inability to complete assessment measures resulted in discrepancies between randomized and analyzed numbers at different time points. It does not provide time-specific or arm-specific analysis counts, reasons for missingness, or the statistical approach used for incomplete observations. This prevents assessment of potential attrition bias and the impact of missing data.

Methodological details are also limited. The record does not report the identity of the masked parties, sequence generation, allocation concealment, treatment duration, session schedule, treatment fidelity, or therapist training. It does not describe the primary analysis model, covariate adjustment, the planned contrast across time points, or sensitivity analyses. The available arm description for PATH-MCI is incomplete.

Although the registry lists six outcome measures and 32 analyses, it does not report a statistical analysis plan or a multiplicity strategy. The safety information gives event counts and selected terms but does not supply event-level context or a formal comparison. These limitations do not establish that the study was improperly conducted; they describe what cannot be assessed from the registry record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Problem Adaptation Therapy for Mild Cognitive Impairment and Depression — NCT03043573.
• Registry record last updated 2025-08-12; status last verified 2025-07.
• Results first posted 2025-08-12.
• 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

NCT03043573 is a completed randomized, single-masked, parallel study of PATH-MCI versus Supportive Therapy for mild cognitive impairment and depression. Enrollment is recorded as 80. The study began on 2017-07-01 and has a primary completion date of 2024-09-19; its phase is listed as NA.

The primary outcome is change in RBANS global cognition, measured at baseline, 12, 24, and 52 weeks. Secondary outcomes listed include disability function, depression, episodic memory, and executive function. The registry notes that pandemic-related disruption and inability to complete assessments led to differences between randomized and analyzed participant numbers across time points.

Serious and other adverse-event counts are reported for both arms, with no deaths listed in either arm. Numerical primary-outcome results and detailed analysis methods are not reported in the registry record, limiting assessment of comparative efficacy, precision, missing-data handling, and multiplicity.