This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Consultation, Advice, and Tailored Support (CATS) for Cancer Survivors (NCT03316170), a randomized phase 2 study. The primary outcome is Retention.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03316170 |
| Phase | Phase 2 |
| Condition | Smoking Cessation, Social Stress |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 49 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Jessica Burris |
| Results posted | Yes |
2. Clinical Question
Population
The trial focused on cancer survivors with low social resources who were being considered for a smoking cessation induction approach. The registry describes the primary outcome population as participants enrolled in the study. It does not report further eligibility details or a more specific description of the participants’ smoking status.
Intervention
The treatment group was assigned Social Support + NRT Sampling. The social support component included a brief phone consultation about free or low-cost resources for unmet social support needs and a written directory of resources delivered by mail. The registry also lists NRT Sampling as an intervention, but the full description of the treatment group is not available in the record.
Comparator
The comparator was Social Support. Its description includes a brief phone consultation about free or low-cost resources to address unmet social support needs and a written directory delivered by mail. The registry identifies the study as randomized, open label, and parallel group.
Primary question
The primary question was about retention: what percentage of enrolled participants had complete assessments at the end of the study, at the Day 60 follow-up? The posted arm-level values are 70.8 for Social Support + NRT Sampling and 72.0 for Social Support. The registry record does not report an estimable two-arm comparison for this outcome, so these percentages describe each arm rather than establishing a statistical difference between groups.
3. Trial Design
This was a randomized, parallel-group phase 2 pilot trial, recorded as completed. The registry lists an enrollment of 49. The Social Support + NRT Sampling arm had 24 participants, and the Social Support arm had 25. The study was open label, meaning masking was not used according to the registry record.
The trial’s stated objectives were to evaluate the feasibility and acceptability of a new smoking cessation induction approach for cancer survivors with low social resources, and to assess its effectiveness for key events in the process of smoking cessation. The registry lists Social Support as a behavioral intervention and NRT Sampling as a drug intervention. The comparator received the social support component without the listed NRT Sampling component.
The registry gives a start date of 2017-11-06 and a primary completion date of 2020-03-31. It records the overall study status as completed. These dates describe the registry record; they do not by themselves explain how long each participant was followed or when every outcome was collected.
Retention was the primary outcome. The record describes it as the number with complete assessments at the end of the study divided by the number enrolled, multiplied by 100. Its timeframe refers to study completion and the number of assessments at Day 60 follow-up. The registry lists three outcome measures, but it reports no posted secondary results. It records one analysis; a detailed statistical analysis plan is not reported in the registry record.
The treatment description for Social Support + NRT Sampling is truncated after the social support components begin to be described. The record therefore does not fully specify the added treatment procedures. Allocation concealment, the randomization sequence method, and any stratification factors are not reported in the registry 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
| Stage | Social Support + NRT Sampling | Social Support |
|---|---|---|
| STARTED | 24 | 25 |
| COMPLETED | 17 | 18 |
| NOT COMPLETED | 7 | 7 |
Reasons for not completing this period:
| Reason | Social Support + NRT Sampling | Social Support |
|---|---|---|
| Death | 1 | 0 |
| Lost to Follow-up | 6 | 7 |
Analysis population for the primary outcome, as defined in the registry: Across all recruitment methods, a total of 551 individuals were contacted about the study; this number is not tied to study arm. Of these 551 individuals, a subset met the eligibility criteria, enrolled in the study, and were then randomized into one of the study arms.
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: Each participant is 1 unit in the analysis
| Characteristic | Unit | Social Support + NRT Sampling | Social Support | Total |
|---|---|---|---|---|
| Participants analysed | 24 | 25 | 49 | |
| Age, Continuous | years | 54.78 (SD 9.27) | 56.00 (SD 10.00) | 55.42 (SD 9.58) |
| Sex: Female, Male: Female | Participants | 14 | 10 | 24 |
| Sex: Female, Male: Male | Participants | 10 | 15 | 25 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 | 0 | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 24 | 25 | 49 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 2 | 2 | 4 |
| Race (NIH/OMB): White | Participants | 22 | 23 | 45 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | Participants | 24 | 25 | 49 |
| Distress Thermometer (NCCN) | units on a scale | 4.21 (SD 2.95) | 4.72 (SD 3.45) | 4.47 (SD 3.19) |
6. Primary Endpoint
The registry lists the primary outcome as Retention, measured over Through study completion, number of assessments at Day 60 follow-up.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percentage of participant w/ assessments |
| Endpoint classification | not reduced to a single comparison |
Retention measures whether participants completed assessments through the study’s endpoint. The registry defines the percentage as the number of participants with complete assessments at the end of the study divided by the number enrolled, multiplied by 100. The stated timeframe is through study completion, with the number of assessments at Day 60 follow-up used in the outcome description.
In a pilot trial, retention is useful because it describes whether participants remain available for outcome assessment. In general, incomplete follow-up can limit how well an outcome reflects the experience of the enrolled participants. Reporting retention can therefore help readers judge the feasibility of collecting follow-up data and interpret other outcomes that depend on assessments being completed. This is a general statistical point, not an additional finding from this trial.
The posted retention values are 70.8 for Social Support + NRT Sampling and 72.0 for Social Support. These are arm-level percentages. The registry record does not report confidence intervals for them or an estimable two-arm comparison. The record also does not describe how partial assessments were classified, how missing assessments were handled in the calculation, or whether particular assessment items were required for an assessment to count as complete. Those details are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary-outcome values are 70.8 for Social Support + NRT Sampling and 72.0 for Social Support. The record describes these values as retention percentages based on complete assessments at study completion. They are descriptive results for the two randomized arms, not an estimate of a demonstrated treatment effect.
The registry specifically indicates that values are missing or not estimable for a two-arm comparison for this count-other endpoint. Accordingly, the posted results do not support a formal statistical comparison of retention between the arms. No confidence interval or p-value for a group contrast is reported in the registry record. Without such an estimate and its uncertainty, readers should not treat the numerical difference between the displayed percentages as evidence of a reliable difference between assignment groups.
The arm sizes were 24 and 25. A percentage from a pilot trial can be informative about the observed follow-up pattern, but it is subject to uncertainty, especially when the group sizes are limited. General statistical practice would describe this uncertainty with an interval estimate when one is available. The registry record does not provide one for this endpoint, so the precision of either percentage cannot be assessed from the posted outcome data alone.
The trial was designed as a pilot with objectives that included feasibility and acceptability as well as assessment of events in the smoking cessation process. The available primary result addresses retention as defined in the registry. It does not, by itself, establish whether the approach was acceptable, whether other cessation-related events differed, or whether the treatment changed smoking behavior. Those conclusions would require relevant reported outcomes and analyses, which are not reported in the registry record.
Random allocation is a design feature intended to support fair comparisons between assigned groups. In general, it does not guarantee that all baseline characteristics will be balanced, and the registry excerpt does not report baseline comparisons. More importantly for this result, randomization cannot substitute for an estimable analysis of the endpoint. The reported arm percentages can be read as a description of retention, while the comparative effect remains unreported.
The registry’s sample-size framework describes planning illustrations based on an observed effect, equal allocation, a two-sided significance level of 0.05, and a normal approximation. Such calculations are planning illustrations, not observed power, and the registry record does not provide a trial-specific design justification in the information available. They should not be read as a substitute for the missing comparative estimate or its uncertainty.
9. Statistical Methods Explained
The study used a randomized parallel-group design. Randomization assigns participants to treatment groups by chance. In general, this supports comparison because assignment is not based on a participant’s prognosis or preference, although chance imbalances can still occur. The registry identifies the study as open label, so masking was not used. It does not report the randomization sequence method, allocation concealment, or any stratification factors.
What does the retention percentage represent?
The endpoint is a percentage formed from completed assessments and enrolled participants. In general, a percentage expresses a part relative to a stated whole. Here, the registry defines the numerator as the number with complete assessments at the end of the study and the denominator as the number enrolled. The outcome description associates the assessment period with Day 60 follow-up. The arm-level values are 70.8 and 72.0.
A percentage summarizes the observed follow-up result, but does not show how much the value might vary across comparable trials. An interval estimate, such as a confidence interval, is commonly used to communicate uncertainty around a sample estimate. In general, a confidence interval gives a range of values compatible with the data under the method’s assumptions; it is not a guarantee that the true value lies in that range. No interval estimates for retention are reported in the registry record.
Why is a group comparison not available?
The registry marks the two-arm comparison as missing or not estimable for this count-other endpoint. Thus, the arm percentages can be described separately, but the posted record does not include a valid estimate of the contrast between them. A comparative analysis would ordinarily state the measure being compared and its uncertainty, and might also report a test statistic or p-value. Those comparative results are not reported in the registry record.
General statistical interpretation distinguishes a descriptive difference in observed group values from evidence about a population-level difference. A comparison needs an appropriate analysis and a measure of precision. The displayed retention percentages alone do not supply those elements. No new comparison should be calculated from the posted percentages when the registry indicates that the two-arm comparison is not estimable.
What can be inferred from the pilot design?
A pilot study can evaluate whether procedures and follow-up are feasible and can provide descriptive information for future research. The registry states feasibility and acceptability as objectives, alongside assessment of key events in the smoking cessation process. Retention is relevant to feasibility because complete follow-up assessments are needed to observe outcomes. However, a retention result does not answer every feasibility or acceptability question. Measures or results for those other questions are not reported in the registry record.
The registry gives a planning framework based on an observed effect, equal allocation, a two-sided significance level of 0.05, and a normal approximation. General sample-size calculations estimate the number of participants needed under specified assumptions to detect an effect at a chosen significance level and power. These calculations are planning illustrations, not observed power. The registry record does not report the trial’s own sample-size justification or a complete statistical analysis plan.
How should the count outcome be understood?
Retention is reported as a percentage rather than as a continuous measurement. For percentage outcomes, uncertainty depends in part on the number of observations and on how the outcome is defined. Here, the record gives arm sizes and percentages, but does not provide interval estimates or details about handling incomplete assessments. It also does not explain whether missing assessments were excluded, treated as incomplete, or handled through another rule beyond the stated definition. These points limit assessment of the precision and reproducibility of the endpoint calculation.
General statistical methods for count or percentage outcomes can account for the fact that variability may differ from the assumptions of a simple normal approximation. Over-dispersion, for example, means that observed variability is greater than a model expects; accounting for it can make uncertainty estimates more realistic. The registry does not report a model for this endpoint, an over-dispersion assessment, or another inferential method. No particular method should therefore be attributed to the analysis beyond what the record states.
Finally, the registry lists one analysis and three outcome measures, while no secondary results are posted. Those entries do not establish which analyses were prespecified, whether interim analyses occurred, or how multiplicity was handled. Such details are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists three outcome measures and indicates that no secondary results are posted. It records one analysis, but does not provide a detailed analysis plan, identify every hypothesis tested, or state whether any interim analyses were conducted. The handling of multiplicity is therefore not reported in the registry record. In general, multiplicity arises when several outcomes or comparisons are tested; repeated testing can increase the chance of a false-positive finding unless the analysis accounts for it. This is general context, not a claim about analyses in this trial.
The primary endpoint is retention, and the registry provides arm-level values. However, it marks a two-arm comparison for this count-other endpoint as missing or not estimable. No comparative confidence interval or p-value is reported. A single recorded analysis does not resolve this limitation because the record does not describe its purpose, methods, or relation to the endpoint.
The endpoint definition relies on complete assessments, but the record does not describe how incomplete follow-up was classified beyond that definition. It does not report a missing-data method, imputation approach, or sensitivity analysis. The analysis population is also not specified beyond the primary outcome’s description of participants enrolled in the study. Whether the posted arm values use an intention-to-treat population, a per-protocol population, or another set of participants is not reported in the registry record.
In general, missing outcome data can affect both the precision and interpretation of a result, particularly if the chance of missingness is related to participant characteristics or outcomes. The retention percentages give information about completed assessments, but do not establish why assessments were missing or how that missingness might affect other study outcomes.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Social Support + NRT Sampling | 0 | 24 | 0.0% |
| Social Support | 0 | 25 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Social Support + NRT Sampling | 1 of 24 |
| Social Support | 0 of 25 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Social Support + NRT Sampling | 8 of 24 |
| Social Support | 10 of 25 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Social Support + NRT Sampling | Social Support |
|---|---|---|---|
| Insomnia | General disorders | 7 of 24 | 8 of 25 |
| Dizziness | General disorders | 5 of 24 | 8 of 25 |
| Dry mouth | General disorders | 6 of 24 | 7 of 25 |
| Weakness | General disorders | 4 of 24 | 8 of 25 |
| Breathing difficulty | Respiratory, thoracic and mediastinal disorders | 6 of 24 | 5 of 25 |
| Heartburn | Gastrointestinal disorders | 4 of 24 | 7 of 25 |
| Headache | Nervous system disorders | 4 of 24 | 5 of 25 |
| Vomiting or nausea | Gastrointestinal disorders | 1 of 24 | 8 of 25 |
| Burning in throat or mouth | General disorders | 3 of 24 | 5 of 25 |
| Diarrhea | Gastrointestinal disorders | 3 of 24 | 4 of 25 |
The registry reports serious adverse events for the two arms. For Social Support + NRT Sampling, the number at risk was 24 and the number affected by a serious adverse event was 0. For Social Support, the number at risk was 25 and the number affected was 0. The registry lists no serious adverse event terms among its top serious terms.
The registry also records other adverse events: 8 for Social Support + NRT Sampling and 10 for Social Support. It lists 1 death in the Social Support + NRT Sampling group and 0 in the Social Support group. These are separate entries in the safety information; the record does not explain whether a death was related to treatment or an adverse event.
These counts should be read as descriptive safety reporting. The registry record does not report the event definitions, severity grading details, attribution to study interventions, or the period over which the events were collected. It also does not provide a statistical comparison of safety outcomes. General statistical interpretation cautions that small group counts can be imprecise and that the absence of reported serious events is not proof that a treatment has no risk. The listed figures alone do not establish causation or comparative safety.
12. What the Result Does, and Does Not, Mean
The primary result describes retention in the two randomized groups: 70.8 for Social Support + NRT Sampling and 72.0 for Social Support. It indicates the reported percentage with complete assessments at study completion under the registry’s definition. Because the record says the two-arm comparison is missing or not estimable, the result does not establish whether retention differed between assignment groups.
The trial’s pilot objectives included feasibility and acceptability, along with assessment of key events in smoking cessation. Retention is relevant to whether assessment follow-up was completed, but it is not a direct measure of smoking cessation, acceptability, or the full feasibility of delivering the intervention. The registry record does not report secondary results that would answer those other questions.
The result also does not establish that adding NRT Sampling caused any change in retention. A causal interpretation of randomized comparisons depends on an appropriate comparative analysis, and that estimate is not reported for this endpoint. The arm percentages should not be treated as proof of equivalence or as proof of a meaningful difference. No confidence intervals or p-values for the comparison are reported in the registry record.
The safety figures are likewise descriptive. The registry reports 0 serious adverse events in each group, along with other adverse event counts of 8 and 10 and deaths of 1 and 0. These entries do not establish whether events were caused by an intervention, whether the groups differed in risk, or whether there were unreported events. Definitions and attribution details are not reported in the registry record.
In general, a pilot result can help characterize the conduct and observed outcomes of a study without providing a definitive answer to an effectiveness question. The posted retention values are useful as an account of follow-up in this trial, but their precision and comparative meaning remain limited by the absence of an estimable group contrast and the lack of interval estimates.
13. Why This Trial Matters Statistically
This trial is statistically informative because its primary endpoint is a practical feature of pilot research: whether participants complete follow-up assessments. Retention can affect the usefulness of later outcome measurements. When many assessments are incomplete, interpretation of outcomes can become more difficult, particularly if missingness is related to participant circumstances or outcomes. This is a general reason to report follow-up clearly.
The registry reports retention percentages for each randomized arm but does not provide an estimable two-arm comparison. That distinction matters. Arm-level summaries describe what was observed in each group; they do not, on their own, quantify the uncertainty in a comparative effect. Readers need to keep descriptive reporting separate from a formal inference about differences between groups.
The study also highlights the role of careful endpoint definitions. The record specifies complete assessments, study completion, and Day 60 follow-up, but does not explain the handling of incomplete or partial assessments. Such details are important for understanding how a percentage was formed and for judging whether the measure could be reproduced in a future study.
Finally, the registry frames the study as a pilot with feasibility and acceptability objectives, but the posted primary result is retention. Keeping those aims distinct helps prevent a retention percentage from being interpreted as evidence about smoking cessation outcomes or intervention acceptability. The record illustrates why outcome-specific results, uncertainty estimates, and clear analysis methods are all needed for a sound statistical reading.
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 registry record leaves important details about the intervention incomplete. The description for Social Support + NRT Sampling is truncated, so the added treatment procedures cannot be fully characterized from the record. The comparator description includes a brief phone consultation and a mailed directory, but the timing and delivery details are not reported beyond the stated description. The trial is open label, and the record does not report whether outcome assessment was conducted by masked staff.
For the primary outcome, the record gives arm-level percentages and group sizes but no confidence intervals or estimable two-arm comparison. It does not describe how incomplete assessments were handled beyond defining retention by complete assessments. The analysis population, missing-data method, and sensitivity analyses are not reported in the registry record.
The study is identified as a phase 2 pilot, and the registry’s stated objectives include feasibility, acceptability, and smoking cessation process events. The record does not report results for the secondary outcomes. It also does not give a trial-specific sample-size justification, a complete statistical analysis plan, or details of any interim analyses. These omissions limit assessment of prespecification and the role of the reported analysis.
Safety reporting is limited by the absence of event definitions, attribution details, and a stated collection period. The record lists serious events, other events, and deaths, but does not provide a comparative safety analysis. These limitations are specific to what is documented in the registry record and should not be read as evidence that unreported procedures or analyses did or did not occur.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Consultation, Advice, and Tailored Support (CATS) for Cancer Survivors — NCT03316170.
- Registry record last updated 2021-07-08; status last verified 2021-06.
- Results first posted 2021-07-08.
- 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.
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18. Record Summary
The registry identifies NCT03316170 as a completed randomized, open-label, parallel-group phase 2 pilot trial of Consultation, Advice, and Tailored Support (CATS) for Cancer Survivors. Enrollment was 49. The groups were Social Support + NRT Sampling, with 24 participants, and Social Support, with 25 participants.
The primary outcome was retention, defined as the percentage with complete assessments at study completion, with the timeframe referring to Day 60 follow-up. The posted arm-level values were 70.8 and 72.0, respectively. A two-arm comparison was marked missing or not estimable. The record lists three outcome measures and no posted secondary results. It also reports serious adverse events of 0 in each arm, other adverse event counts of 8 and 10, and deaths of 1 and 0.
The study began on 2017-11-06 and reached primary completion on 2020-03-31. Details of the comparative analysis, missing-data handling, and complete treatment procedures are not reported in the registry record.