Self-System Therapy for Older Adults With Lung Cancer: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Self-System Therapy for Older Adults With Lung Cancer (NCT04057196), a na na study. The primary outcome is Number of Patients That Complete SST Treatment Sessions.

2. Clinical Question

The study focused on whether older adults with advanced lung cancer completed a course of Self-System Therapy. Its stated purpose was to address depression and lung-cancer-related distress; the intervention description also refers to illness-related distress and enhancing self-efficacy through behavioral coping skills. The primary endpoint is therefore a treatment-completion measure, rather than a direct measure of depression, distress, or self-efficacy.

The registry also identifies secondary assessments of general distress using CORE-10 and depression using BDI-II at baseline, 12 weeks, and 1-month follow-up. Other listed measures concern functioning, assessed with FACT-L, and the availability of participant-reported mobility indices. These are additional questions about participant experience and assessment, but the registry record does not report their results.

Because there is no comparator group, the central question is descriptive: how many participants met the stated completion definition? The record does not report that count. It therefore cannot establish from the posted results how often participants completed treatment, nor whether any changes in distress, depression, functioning, or other outcomes occurred.

3. Trial Design

The registry identifies NCT04057196 as a completed, single-group behavioral study sponsored by Duke University. It lists an enrollment of 30 and describes the study population as older adults with stage III or stage IV lung cancer. The brief description specifies adults 65 years and older. The listed intervention is Self-System Therapy for Older Adults with Advanced Lung Cancer, abbreviated SST-LC, delivered across a 12-week period.

The design has no stated control arm: allocation is listed as not applicable, and masking is listed as none. This means the registry record does not describe a randomized allocation or a blinded comparison. The study is not structured to compare SST-LC with another treatment or with usual care. Its primary endpoint counts participants meeting a prespecified treatment-completion criterion, so the design primarily addresses feasibility or participation in the intervention rather than a comparative treatment effect.

The registry lists a start date of 2020-04-02 and a primary completion date of 2021-05-20, with status marked completed. These record entries do not by themselves show how many participants began treatment, completed follow-up, or contributed data to each outcome. Those details are not reported in the registry record.

The secondary outcomes include repeated measures of general distress and depression, as well as functioning and the availability of mobility indices. The registry identifies 14 outcome measures overall, but lists zero analyses. It does not report a statistical analysis plan, an analysis population, or results for the primary or secondary outcomes. Consequently, the design can be described from the registration, but the results and analytic procedures cannot be reconstructed from that record.

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:

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 Number of Patients That Complete SST Treatment Sessions, measured over up to week 12.

The primary endpoint is the number of patients who complete SST treatment sessions. The registry defines completion as attending at least 85% of the SST sessions across a 12-week period. It is recorded as a count of participants, with the timeframe described as up to week 12.

This endpoint is useful for describing whether participants engage with and complete the planned behavioral intervention. Completion is a practical feature of an intervention: it records whether participants met a stated participation threshold. It does not directly measure depression, distress, self-efficacy, or functioning, and it should not be interpreted as evidence of improvement in those outcomes.

A count is most interpretable alongside the number of participants eligible for the endpoint and a clear account of who was assessed. The registry lists enrollment of 30, but it does not post the number who met the completion definition, the number with endpoint data, or a participant flow describing treatment initiation and follow-up. The primary endpoint result is therefore not reported in the registry record. Without that result, the completion rate cannot be described from the posted information.

The endpoint's threshold gives a clear rule for classifying completion, but the record does not provide additional details about session attendance recording or how incomplete attendance data were handled. Those procedures are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The statistical information in the registry is limited. It identifies a single-group study, a participant-count primary endpoint, and secondary measures, but lists zero analyses. A statistical analysis plan, including the precise methods used to summarize or compare outcome measurements, is not reported in the registry record. The concepts below explain how such outcomes are generally interpreted; they do not describe analyses documented for this study.

What does a participant count describe?

A count records how many participants meet a defined condition. For this study, that condition is completion of at least 85% of SST treatment sessions across a 12-week period. A count is a direct description of participants meeting the rule, but readers also need its denominator and information about participants whose completion status is unavailable. The registry lists enrollment of 30, but does not report the endpoint count, the number with ascertainable completion status, or how missing attendance information was treated. A completion proportion or uncertainty interval cannot be interpreted without the relevant result and denominator.

Counts can be summarized with uncertainty intervals when the underlying data and analysis are available. In general, a confidence interval describes a range of values compatible with the data and the specified statistical method; it is not a guarantee that the true value lies within that range. No confidence interval for the primary endpoint is reported in the registry record.

What can a single-group design estimate?

A single-group study can describe outcomes among participants who take part, provided the relevant results and analysis are reported. It has no concurrent comparator in this registry record. General statistical principle: a change measured over time in one group does not, by itself, isolate the effect of an intervention. Other influences may also contribute to an observed change. A randomized comparison is one common way to estimate differences between assigned groups, but no such comparison is described for this study.

The absence of a comparator also means that a between-group treatment effect cannot be calculated from this design as registered. A within-group change, if reported, would answer a different descriptive question. The registry does not post the scores or analyses needed to characterize even that change.

How should the secondary measures be understood?

The registry names CORE-10 for general distress and BDI-II for depression at baseline, 12 weeks, and 1-month follow-up. Repeated measurement can describe how scores vary across assessment times. General statistical principle: analysis of repeated measures must account for the fact that measurements from the same participant are related, rather than treating them as independent observations. Which method was used, whether scores were analyzed as changes or levels, and how incomplete repeated measurements were handled are not reported in the registry record.

FACT-L is listed as a measure of functioning, and the registry also lists the number of participants with participant-reported mobility indices available. The record does not provide outcome values, definitions beyond those descriptions, or analytic details for these measures. No result should be inferred merely from the fact that an outcome was registered.

What do planning illustrations mean?

The registry's stated planning assumptions describe illustrations based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They describe the effect to detect as a stated fraction of the observed effect. Time-to-event illustrations use a total event count; other illustrations use participants per arm. These are planning assumptions, not reported trial results.

Those two-arm assumptions do not match the registered single-group design. In addition, the registry does not report an observed effect estimate or a trial analysis from which to assess the illustration. Such calculations should therefore be read as hypothetical planning examples, not as evidence about the study's achieved precision or as observed power. The sample size justification for the actual study is not reported in the registry record.

Why does over-dispersion matter in general?

General statistical principle: for count outcomes, over-dispersion means the observed variability is greater than a chosen count model expects. If it is ignored, uncertainty estimates may be too narrow and statistical tests may be poorly calibrated. This study's primary endpoint is described as a count of participants, but no distributional model or dispersion estimate is reported. There is no basis in the registry record to say that over-dispersion was assessed or that a particular count model was used.

In short, the record supplies enough design description to clarify the endpoint and study structure, but not enough analysis detail or outcome data to reproduce an estimate. The registered definitions should be distinguished from actual results, and general statistical concepts should not be mistaken for documented methods used in this study.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Adults With Advanced Lung Cancer")
n      <- c(30)
events <- c(23)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Adults With Advanced Lung Cancer  30  23  76.7  57.7  90.1  59.1  88.2  58.9  88.1

11. Multiplicity, Missing Data and Analysis Populations

The registry lists several secondary outcomes, including general distress and depression at baseline, 12 weeks, and 1-month follow-up, plus functioning and mobility-related measures. It reports 14 outcome measures overall but lists zero analyses. A multiplicity strategy—such as identifying a hierarchy of outcomes or adjusting for multiple statistical tests—is not reported in the registry record. Since no outcome analyses are posted, it is not possible to assess how multiple outcomes or assessment times were handled.

Missing-data procedures are also not reported in the registry record. The record does not state how many participants had missing assessments, whether participants who discontinued treatment were followed, or whether imputation or another method was used. The listed mobility outcome concerns the number of participants with participant-reported mobility indices available, but it does not give that number or explain how unavailable indices were handled.

The analysis populations are not reported in the registry record. It is not stated whether analyses included all enrolled participants, only participants who began SST-LC, only participants with complete measurements, or another group. The registry's enrollment of 30 does not establish the number included in any particular analysis.

These omissions limit interpretation in different ways. Without a multiplicity approach, any collection of tests would need cautious interpretation; without missing-data information, readers cannot assess whether the observed data represent all enrolled participants; and without analysis-population definitions, the population represented by an estimate would be unclear. Here, the record does not post estimates or tests to evaluate, so these analytic details remain unknown rather than demonstrating that a particular method was or was not used.

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.

Most frequent serious adverse event terms

Serious events with the highest arm-level rate: unfavorable changes in health, due to disease progression (10.0%).

The registry safety entry lists 3 participants with serious adverse events among 30 at risk, 0 participants with other adverse events, and 3 deaths in the adults-with-advanced-lung-cancer group. The most frequently listed serious-event term is unfavorable changes in health, due to disease progression, reported as 10.0%. These figures are descriptive registry entries, not a comparative safety analysis.

The count of deaths should not be treated as evidence that the intervention caused them. The registry record does not report an attribution assessment, a comparison group, or details that would establish the relationship between the intervention and an event. The event term referring to disease progression likewise does not establish whether any individual event was related to SST-LC.

General statistical principle: safety counts are interpreted in light of the population observed, the length and completeness of follow-up, event definitions, and how events were attributed and collected. The registry record does not report all of those details. The count of 0 for other adverse events should be read as the listed count, not proof that no unrecorded or unobserved events occurred. These entries alone cannot establish comparative risk or causality.

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

The registry record establishes that the study was designed to deliver SST-LC to older adults with stage III or stage IV lung cancer and to assess treatment completion and other outcomes. It defines primary completion as attending at least 85% of sessions across a 12-week period. It also identifies assessments of general distress, depression, functioning, and mobility-related information.

What the record does not establish is how many participants met the completion definition or what happened to the secondary outcome measures. No primary outcome count, score summaries, changes, uncertainty intervals, or statistical tests are reported. That absence does not mean that participants did not complete treatment, that their symptoms did not change, or that there was no effect. It means those results are not reported in the registry record.

The single-group design also limits what any reported change could mean. Without a comparator, outcomes cannot be contrasted against an alternative group to estimate a comparative effect. General statistical principle: observed changes over time can reflect multiple influences, so a before-and-after difference alone cannot establish that the intervention caused the change.

The safety counts should be interpreted with similar care. They describe serious events, other events, and deaths recorded in the registry, but do not establish that the intervention caused or prevented any event. There is no comparative safety estimate in the record.

The most defensible interpretation is therefore about scope rather than effect: this completed study registered a behavioral intervention and a treatment-completion endpoint, but the posted record does not include the analyses needed to quantify completion or outcomes. Conclusions about symptom benefit, comparative effectiveness, or causal safety cannot be drawn from the registry information alone.

14. Why This Trial Matters Statistically

This study is statistically notable because its primary question is about whether participants complete a behavioral intervention, rather than a direct comparison of clinical outcomes between treatment groups. A clearly defined completion threshold can make a feasibility question concrete: the endpoint specifies what counts as completing SST sessions. That definition is useful, but a result is needed to describe how many participants met it. The registry record does not report that result.

The study also illustrates why design and analysis must be considered together. A single-group structure can support descriptive reporting, but it does not provide a concurrent comparison for estimating a relative treatment effect. Readers should distinguish evidence that an intervention was delivered and outcomes were registered from evidence that outcomes changed because of the intervention.

Repeated measures of distress and depression could, if reported, describe participant scores at baseline, 12 weeks, and 1-month follow-up. Interpretation would depend on the score results, the number of participants assessed at each time, and the methods used for repeated observations and missing data. Those details are not reported in the registry record. Statistical precision cannot be assessed without estimates and uncertainty measures.

Finally, the registry's planning assumptions describe hypothetical two-arm sample-size illustrations even though the registered design is single-group. Recognizing that distinction prevents a planning calculation from being mistaken for an analysis of the actual design or for evidence of achieved statistical power. The record is useful for understanding the study question and its limitations, while its missing outcome analyses leave the central empirical findings unresolved.

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.

Several limitations specific to this study follow from the registry information. The design is single-group, with no registered comparator. It can therefore describe the intervention cohort but cannot directly estimate how outcomes compare with another treatment or with no intervention. The registry lists no masking, so blinded assessment is not described.

The primary endpoint is treatment completion, but its result is not posted. The registry lists enrollment of 30 without reporting the number who started treatment, the number with ascertainable completion status, or the number meeting the completion threshold. The endpoint's denominator and the handling of unavailable attendance data are therefore unclear.

The record registers secondary measures of distress, depression, functioning, and mobility, but reports no outcome analyses. It does not provide score distributions, changes, uncertainty estimates, or details of missing observations. Analysis populations, multiplicity procedures, and the statistical analysis plan are not reported in the registry record. The absence of these details prevents assessment of how the registered outcomes were evaluated.

The safety information is also limited. Counts are listed, but the registry does not report enough detail to determine event timing, attribution, or comparative risk. The listed deaths and serious adverse events should not be interpreted as intervention-caused outcomes.

Finally, the planning assumptions describe equal allocation between two arms, although the registered study is single-group. The sample-size justification for the actual design and any interim analyses are not reported in the registry record. These limitations concern what can be concluded from the record; they do not establish that unreported procedures or analyses did not occur.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Self-System Therapy for Older Adults With Lung Cancer — NCT04057196.
• Registry record last updated 2022-08-03; status last verified 2022-07.
• Results first posted 2022-08-03.
• 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

NCT04057196 is registered as a completed, single-group behavioral study sponsored by Duke University. The registry lists enrollment of 30 older adults with stage III or stage IV lung cancer and describes SST-LC as a 12-week intervention. Its primary endpoint is the number of participants completing at least 85% of treatment sessions.

The registry also lists distress and depression measures at baseline, 12 weeks, and 1-month follow-up, along with functioning and mobility-related outcomes. It identifies 14 outcome measures and zero analyses. The primary completion count and secondary outcome results are not reported in the registry record.

Safety entries include 3 participants with serious adverse events among 30 at risk, 0 with other adverse events, and 3 deaths. The top serious-event term is unfavorable changes in health, due to disease progression, at 10.0%. These entries do not establish causation. Overall, the record describes the study question and endpoints but does not post the analyses needed to quantify completion or outcome changes.