Tobacco Use Treatment in Cancer Patients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Tobacco Use Treatment in Cancer Patients (NCT03482583), a non-randomized phase 4 study. The primary outcome is Smoking 7-Day Point Prevalence at 12 Weeks.

2. Clinical Question

The broader purpose was to examine ways to improve access to and use of tobacco treatment at UF Health Cancer Center. The registry describes a mixed-methods approach to understanding patient, provider, and organizational factors that influence implementation, and to evaluating the feasibility of a multi-level intervention. That purpose is important for interpreting the outcome: the study is presented as informing the design of a pragmatic clinical trial, not as a randomized efficacy trial.

There is a naming difference between the intervention descriptions and the outcome description. The intervention descriptions name cognitive behavior therapy with nicotine replacement therapy, referral to the Area Health Education Center, and referral to Quitline. The outcome description names PhoneQuit, SmartQuit, and GroupQuit. The registry record does not explain how these labels correspond, so their identities should not be matched by assumption.

3. Trial Design

NCT03482583, titled Tobacco Use Treatment in Cancer Patients, is a completed, non-randomized, parallel study sponsored by the University of Florida. The registry reports 90 participants enrolled. The recorded study start was 2018-05-14 and primary completion was 2019-12-31. The phase is listed as PHASE4, and masking is listed as none.

The study addresses implementation of tobacco treatment at UF Health Cancer Center. Its summary describes suboptimal access to and utilization of treatment, and identifies the center's largely rural catchment area and burden of tobacco-related disease as relevant context. The stated objective was to use mixed methods to assess contextual factors and evaluate the feasibility of implementing a multi-level intervention intended to increase treatment utilization and improve health outcomes. The work was also intended to inform the design of a pragmatic clinical trial.

Intervention descriptions include cognitive behavior therapy delivered by a certified tobacco treatment specialist using a video platform, with nicotine replacement therapy offered to interested participants; referral to the Area Health Education Center; and referral to Quitline. The registry's primary outcome description, however, reports results under PhoneQuit, SmartQuit, and GroupQuit. How these names relate to the intervention descriptions is not reported in the registry record.

Because allocation was non-randomized, the groups should not be interpreted as if participants had been randomly assigned to interchangeable treatments. The registry specifically cautions that the arms are not a like-for-like control comparison. Differences in outcomes could reflect differences in participants, implementation, or other contextual factors as well as any difference in the treatment approaches; the record does not provide information to separate these possibilities. Further details of allocation procedures, eligibility criteria, recruitment, and follow-up completeness 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

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 Smoking 7-Day Point Prevalence at 12 Weeks, measured over 12 weeks.

The primary outcome is titled Smoking 7-Day Point Prevalence at 12 Weeks and is measured in participants. It describes whether participants reported abstinence from smoking during the 7-day period referenced by the endpoint at the 12-week assessment. This is a binary outcome for each participant: the reported endpoint counts participants meeting the abstinence definition, rather than measuring the number of cigarettes smoked by each person.

The registry says the outcome used an intent-to-treat analysis. It reports that 3 (7.7%) PhoneQuit, 2 (5.4%) SmartQuit, and 2 (14.3%) GroupQuit patients reported 7-day point prevalence abstinence. SmartQuit abstinence was verified with carbon monoxide readings. The registry does not describe verification for the other named groups, the precise handling of participants whose smoking status was unavailable, or the assessment procedures in further detail.

Point-prevalence abstinence is used to describe smoking status over a defined recent period at a specified assessment. It does not, by itself, describe continuous abstinence throughout follow-up or establish how long an individual remained abstinent. The registry also lists change in cigarettes smoked per day as a secondary outcome, but the primary outcome is the reported 12-week abstinence measure.

The outcome's group names differ from the names used for the listed intervention descriptions. The registry record does not clarify the mapping. Accordingly, the outcome values should be attributed to the names used in the outcome description rather than assigned to a particular intervention description without further documentation.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry gives limited detail about the statistical methods. It identifies the primary outcome as a participant count, describes the endpoint as binary, and says the 12-week outcome was analyzed using intent-to-treat. The registry record does not report a full statistical analysis plan, model specification, inferential tests, confidence intervals, or procedures for covariate adjustment. The following concepts explain how such outcomes are generally understood, without attributing unreported procedures to this study.

What does a binary outcome represent?

A binary outcome classifies each participant into one of two states for the endpoint, such as meeting or not meeting an abstinence definition at the assessment. A count records how many participants meet the definition. A percentage expresses that count relative to an eligible analysis denominator. For the smoking endpoint, the registry reports participant counts and percentages by the names PhoneQuit, SmartQuit, and GroupQuit. It does not provide the denominators alongside those results, so the percentages cannot be independently checked from the outcome description alone.

Binary outcomes can be summarized descriptively, as in the posted counts and percentages, or analyzed with statistical models that compare probabilities across groups. A model-based comparison requires decisions about the outcome definition, group structure, covariates, and treatment of missing observations. Those decisions are not reported in the registry record. No model or adjusted effect estimate should therefore be inferred from the descriptive results.

What does intent-to-treat mean?

In general, an intent-to-treat approach aims to analyze participants according to their original group assignment or enrollment group, regardless of treatment received or adherence. This approach can preserve the advantages of random allocation when a trial is randomized. In a non-randomized study, the term does not itself make groups comparable or remove confounding. Here, the registry states that the primary outcome used intent-to-treat analysis, but does not describe the assignment rule or how participants with unavailable outcome data were handled. Those details are not reported in the registry record.

Missing outcome data matter because the observed participants may not represent everyone enrolled. If participants with missing smoking assessments differ from those assessed, a complete-case summary can be biased. Common approaches in general include defining missing outcomes in a prespecified way, using imputation, or conducting sensitivity analyses. These are general options, not methods established for this study. The registry record does not report which approach, if any, was used.

Why does non-random allocation matter?

Randomization is designed to balance measured and unmeasured characteristics between comparison groups on average. Non-randomized allocation does not provide that protection. Participants may enter or be directed to groups for reasons related to their preferences, circumstances, or service availability. Those same factors could also relate to smoking outcomes. Adjustment for measured characteristics may sometimes help, but cannot guarantee removal of unmeasured differences. The registry does not report a comparative adjustment strategy, and it cautions that the arms are not a like-for-like control comparison.

The parallel model indicates that groups are considered alongside one another rather than as successive periods in a crossover design. It does not imply random allocation or equal baseline characteristics. Masking is listed as none. The record does not describe whether outcome assessors were masked, and no such procedure should be assumed.

How should precision be understood?

A point estimate, such as a reported percentage, gives a single summary of the observed data. A confidence interval is a general statistical tool for showing uncertainty around an estimate under a specified method and assumptions. Wider intervals indicate less precision; narrower intervals indicate greater precision. The registry does not report confidence intervals or other uncertainty measures for the primary results, so their precision cannot be quantified from the posted outcome summary.

Likewise, a p-value would address how compatible data are with a specified null model, under its assumptions; it would not measure the probability that a treatment works or establish clinical importance. No p-values or formal group-comparison tests are reported in the registry record. The listed zero analyses also means there are no registry-posted analysis records to supplement the descriptive outcome text.

What is the role of the planning illustration?

The registry's planning illustration is described as a calculation based on an observed effect, not as the study's own design justification. It assumes a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; its target effect is a stated fraction of the observed effect. For time-to-event outcomes, the stated quantity is total events using the Schoenfeld approach; for other outcomes, it is participants per arm. These are planning assumptions, not observed trial results and not evidence of achieved power.

In general, sample-size planning estimates the amount of information a future study might need to detect a specified effect under chosen assumptions. When an observed effect is used as the basis, the estimate can be sensitive to uncertainty in that observed effect. Planning for a smaller fraction of an observed effect is a way to consider a less ambitious target, but no additional calculation should be inferred without the stated values. The registry record does not report the original sample-size justification or provide a basis for treating the illustration as a prospective design plan for 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("Cognitive Behavior Therapy With NRT", "Referral to Area Health Education Center", "Referral to Qutiline")
n      <- c(37, 14, 39)
events <- c(2, 2, 3)
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  Cognitive Behavior Therapy With NRT  37  2  5.4  0.7  18.2  1.5  17.7  1.7  17.7
ARM  Referral to Area Health Education Center  14  2  14.3  1.8  42.8  4.0  39.9  4.3  40.5
ARM  Referral to Qutiline  39  3  7.7  1.6  20.9  2.7  20.3  2.8  20.4

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 5 outcome measures and identifies change in cigarettes smoked per day as a secondary outcome. The primary outcome is smoking 7-day point prevalence at 12 weeks. The record does not give a complete account of all outcome definitions, assessment times, or the order in which analyses were planned. A statistical analysis plan, including any strategy for managing multiple comparisons, is not reported in the registry record.

Multiplicity arises when investigators make several statistical comparisons or evaluate several outcomes. Considering many results can increase the chance of a chance finding if each is interpreted as confirmatory. In general, a prespecified hierarchy or an adjustment method can address this concern, depending on the study's aims. Neither a hierarchy nor a multiplicity adjustment is reported for this study. Since the registry reports descriptive primary-outcome counts and percentages but no inferential tests, it is not possible to determine how multiplicity would affect a formal comparison.

The registry describes the primary outcome analysis as intent-to-treat. It does not report the number of participants with an observed outcome in each named group, the amount or pattern of missing outcome data, or how missing data were handled. It also does not report whether all enrolled participants were included in each endpoint analysis. The term intent-to-treat should therefore not be taken as evidence that every enrolled participant contributed a measured outcome or that missing outcomes were handled in a particular way.

Analysis populations are not described beyond the intent-to-treat statement for the primary outcome. The record does not identify a per-protocol population, a safety population definition, or rules for participants who did not receive the intended service. These omissions limit assessment of how closely the analyzed participants correspond to the enrollment and intervention groups. The registry reports zero analyses, while still providing a narrative outcome result; details of any additional statistical work are not reported in the registry record.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry reports serious adverse events and other adverse events by intervention group. For cognitive behavior therapy with nicotine replacement therapy, 37 participants were listed at risk, with 0 serious events, 0 other events, and 0 deaths. For referral to the Area Health Education Center, 14 were listed at risk, with 0 serious events, 0 other events, and 0 deaths. For referral to Quitline, 39 were listed at risk, with 0 serious events, 0 other events, and 0 deaths. No top serious adverse-event terms are listed.

These entries mean that the registry records zero events in the reported categories for the listed groups. They do not establish that no symptoms or other health events occurred, because the record does not describe the full event definitions, monitoring procedures, reporting thresholds, or completeness of follow-up. A zero count is also not a guarantee that an event cannot occur; it is a description of the events recorded in this registry entry.

The numbers at risk are reported for the intervention descriptions, while the primary outcome uses the different names PhoneQuit, SmartQuit, and GroupQuit. The registry does not explain whether these labels correspond. Safety figures should therefore remain attached to their stated intervention-group labels and should not be combined with, or used as denominators for, the primary abstinence percentages without further documentation.

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

The registry's primary outcome provides a descriptive account of reported abstinence at 12 weeks: 3 (7.7%) in PhoneQuit, 2 (5.4%) in SmartQuit, and 2 (14.3%) in GroupQuit. SmartQuit abstinence was verified with carbon monoxide readings. These figures summarize the outcome reporting in the registry; they are not, on their own, estimates of a causal treatment effect.

The distinction matters because this was a non-randomized study and the registry says its arms are not a like-for-like control comparison. Without random allocation or adequate information about group differences and adjustment, outcome differences cannot be attributed confidently to the intervention approach. The registry does not report a formal comparison, confidence intervals, or p-values for the group results. The observed percentages therefore do not establish that one approach is better or worse than another.

The study's stated role was to assess contextual factors and feasibility of implementation, and to inform design of a pragmatic clinical trial. Its value should be read in that context. It provides reported outcome counts alongside descriptions of service approaches, but the record does not supply enough information to assess implementation fidelity, participant flow, baseline comparability, or missing assessments. The different group labels used in the intervention and outcome descriptions add uncertainty about how the reported results map to the listed services.

The endpoint concerns recent smoking status at a 12-week assessment. It does not, by itself, establish continuous abstinence over the whole follow-up period, long-term outcomes, or changes in cancer outcomes. Although the registry lists change in cigarettes smoked per day as a secondary outcome, results for that measure are not reported in the registry record.

Accordingly, the result supports a narrow conclusion: the registry records the stated abstinence counts and percentages in the outcome groups, in a non-randomized implementation-focused study. It does not establish treatment efficacy, comparative superiority, or effects beyond the reported endpoint and setting. These limitations are reasons to interpret the findings cautiously, not evidence that an approach did or did not work.

14. Why This Trial Matters Statistically

This study raises statistical questions that are central to implementation research: how service approaches are delivered in a real care setting, what influences their use, and how early outcome information can guide the design of later research. The registry describes a mixed-methods effort at UF Health Cancer Center, with patient, provider, and organizational factors in view. That focus differs from a randomized trial designed primarily to estimate a comparative treatment effect.

For interpretation, the distinction between implementation feasibility and efficacy is important. A feasibility study can help identify practical issues and generate information for subsequent study design. Its descriptive outcome results should not automatically be treated as a definitive comparison. Here, allocation was non-randomized, the registry explicitly warns that arms are not a like-for-like control comparison, and the primary outcome report does not include inferential comparisons or uncertainty estimates.

The record also illustrates why consistent group definitions matter. The intervention descriptions and the primary outcome use different labels, and the registry does not explain their relationship. Clear mapping of groups, outcome denominators, and analysis populations is necessary for readers to understand which participants contributed to each result and what each comparison represents. That information is not reported in the registry record.

The project is described as informing a pragmatic clinical trial to improve delivery of tobacco treatment services to cancer patients. A future study can build on implementation questions while specifying its allocation strategy, outcomes, analysis populations, missing-data procedures, and methods for estimating uncertainty. Those details would allow readers to distinguish descriptive findings from comparative evidence and to judge how precisely effects are estimated.

The statistical importance of this record lies in that boundary: outcome numbers can be informative without being definitive. Reading them in light of design, reporting, and stated purpose helps keep conclusions proportional to what the registry documents.

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 registry record leaves important details unavailable for interpreting the primary outcome. It does not report the outcome denominator for each named group, participant flow, baseline characteristics, or the extent and handling of missing smoking assessments. Although the outcome description says intent-to-treat, the procedures used to define that population and address unavailable outcomes are not reported.

There is a discrepancy in group naming within the record: intervention descriptions name cognitive behavior therapy with nicotine replacement therapy, referral to the Area Health Education Center, and referral to Quitline, while the outcome description names PhoneQuit, SmartQuit, and GroupQuit. The registry does not provide a mapping between these labels. This prevents confident attribution of the primary outcome figures to the intervention descriptions.

The study is non-randomized, and the registry warns that the arms are not a like-for-like control comparison. The record does not provide information sufficient to assess group comparability or identify a strategy to adjust for possible confounding. It also reports no confidence intervals, p-values, or formal comparative analyses. The posted counts and percentages therefore provide limited information about precision and do not establish causal differences.

Further design and implementation details are not reported in the registry record, including eligibility criteria, recruitment procedures, intervention uptake and adherence, and outcome-assessment procedures beyond the SmartQuit carbon monoxide verification statement. The registry describes a mixed-methods approach, but does not provide the methods or findings for those components in the information summarized in this record.

Finally, the record lists change in cigarettes smoked per day as a secondary outcome but does not report its results. It lists 5 outcome measures, but does not provide a full analysis plan or multiplicity strategy. These gaps limit evaluation of completeness and selective reporting. They do not imply that unreported procedures or results were absent; they mean those details are not reported in the registry record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Tobacco Use Treatment in Cancer Patients — NCT03482583.
• Registry record last updated 2020-05-22; status last verified 2020-05.
• Results first posted 2020-05-22.
• 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

NCT03482583 is a completed, non-randomized, parallel study sponsored by the University of Florida, with 90 participants enrolled. The recorded start date is 2018-05-14, and primary completion is recorded as 2019-12-31. The study concerns tobacco treatment for cancer patients at UF Health Cancer Center and is described as a mixed-methods assessment of implementation context and feasibility.

The primary outcome is smoking 7-day point prevalence at 12 weeks. The registry reports 3 (7.7%) PhoneQuit, 2 (5.4%) SmartQuit, and 2 (14.3%) GroupQuit patients reporting abstinence; SmartQuit abstinence was verified with carbon monoxide readings. The intervention descriptions use different group names, and their relationship to the outcome labels is not reported.

The registry cautions that the study arms are not a like-for-like control comparison. It does not report confidence intervals, formal comparative tests, details of missing-data handling, or a full analysis plan. Adverse-event entries record zero serious events, zero other events, and zero deaths in each listed intervention group. These entries describe the recorded categories and should not be interpreted as proof that all possible harms were absent.