Smoking Cessation for Smokers With Sleep Problems: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Smoking Cessation for Smokers With Sleep Problems (NCT01277887), a randomized na study. The primary outcome is Smoking Abstinence.

2. Clinical Question

This is a question about a comparison between two behavioral approaches within a treatment program that includes nicotine patches, rather than a comparison of counseling with no intervention or of patch use with no patch. That distinction matters for interpretation: any reported contrast would relate to the counseling strategies as delivered alongside the patch. The study is described as a pilot, and enrollment was 19. The registry record does not give detailed eligibility rules, recruitment methods, or the number of participants in each randomized arm for the primary outcome. It also does not report a primary-outcome estimate or a statistical test that would answer the comparative question.

3. Trial Design

The registry describes a randomized, double-masked, parallel-group study with an enrollment of 19. Random allocation means that assignment was intended to use chance, but the method used to generate or conceal the assignment is not reported in the registry record. The record labels the study double-masked; it does not identify which participants, investigators, or other study personnel were masked, or explain how masking was maintained. The study phase is listed as NA.

Both arms involved 8 counseling sessions over 10 weeks. In both, counseling began 4 weeks before the quit date, and participants received a nicotine patch for 6 weeks beginning on that date. The named approaches were Cognitive-Behavioral Counseling and Smoking Cessation Counseling. Because the patch and the broad schedule were shared, the intended contrast is between these two counseling approaches as implemented in the study, not between patch and no patch.

The record describes three parts: an intake session, a 10-week treatment phase, and a 1-month follow-up. The listed start is 2010-12, the primary completion is 2012-03, and the status is COMPLETED. The primary outcome is titled Smoking Abstinence. Its timeframe is recorded as 1 Week, while its operational description mentions both the last 7 days of the last week of treatment and the last 7 days at the first follow-up visit 4 weeks after completing treatment. These details are reported as written; the registry does not explain how the timeframe label relates to the full definition.

Secondary outcomes named in the record are Self-Control to Resist Smoking Cues and Sleep Efficiency. More detailed procedures for measuring these outcomes, the schedule of assessments, and the planned statistical analysis 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.

Before assignment: Prior to randomization, inclusion and exclusion criteria were assessed. Reasons for exclusion included CBT-I contraindicated medical/psychiatric conditions, not meeting smoking criteria, other drug dependence, and not meeting sleep criteria.

Pre-Quit Treatment Phase

Reasons for not completing this period:

Post-Quit Treatment Phase

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 Smoking Abstinence, measured over 1 Week.

The primary endpoint is titled Smoking Abstinence and is expressed as a number of participants. The registry operationally describes abstinence as no smoking during the last 7 days of the last week of treatment and no smoking during the last 7 days at the first follow-up visit, which was 4 weeks after treatment ended. The endpoint description therefore refers to smoking status over specified periods, rather than simply stating whether a participant ever smoked during the study.

Abstinence is a binary outcome at the participant level: a participant either meets the stated definition or does not. Counts can communicate how many participants in each arm met the definition, while a comparative analysis can estimate how the probability of meeting it differs between arms. The registry record does not report those outcome counts or a comparative estimate. It also does not clarify whether the definition requires meeting both stated conditions, or how a participant with missing smoking-status information would be classified.

The timeframe field says 1 Week, but the written definition includes a treatment-end period and a follow-up period. That mismatch should be kept in view when reading the endpoint. A clearly specified outcome and assessment time are important because conclusions depend on what counts as abstinence and when it is assessed. The registry record does not report further verification procedures, such as whether smoking status was confirmed by a separate measure. In general, an endpoint definition helps make a result interpretable and reproducible; it does not, by itself, establish how completely the outcome was measured in a particular trial.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

This study is described as randomized and parallel-group. In general, randomization assigns participants to study arms by chance, which can help balance measured and unmeasured characteristics on average. It does not guarantee that groups will be alike in a small trial, and the registry record does not report the randomization sequence method or allocation-concealment procedure. A parallel-group design assigns participants to an arm and compares outcomes between arms; the record does not describe crossover or switching procedures.

What does double masking tell readers?

The registry labels the study double-masked. Masking is intended to reduce the influence of knowledge about assigned treatment on behavior, outcome assessment, or other study processes. The label alone does not identify who was masked or how masking worked. Those details, including whether participants and outcome assessors were masked, are not reported in the registry record. Because both arms used counseling with different names and both included a nicotine patch, the record alone is not enough to determine how participants or staff experienced or recognized the assigned approach.

How should a participant count be understood?

The primary outcome is a count of participants meeting a smoking-abstinence definition. A binary outcome has two possible participant-level states for analysis: meeting or not meeting the specified definition. Counts by arm are a direct descriptive summary. A comparison could be expressed in several ways, such as a difference in proportions or a relative measure, but the registry record does not report a selected measure or any values for this endpoint. No new comparison can be reconstructed without the arm-specific primary-outcome data and the analysis conventions.

A confidence interval, in general, describes a range of values compatible with the data and the statistical method used, while reflecting sampling uncertainty. A narrow interval indicates greater precision than a wide interval, all else equal. A p-value, in general, describes how unusual data at least as incompatible with a specified null model would be if that model and the analysis assumptions held. Neither quantity is reported for the smoking-abstinence comparison in the registry record. Statistical significance, if reported, would not by itself express the size or practical meaning of an effect; interpretation also requires an estimate and its uncertainty.

What can be said about sample-size planning?

The record describes a planning illustration based on the observed effect, using a two-sided significance level of 0.05, equal allocation, and a normal approximation. It frames the effect to detect as a stated fraction of the observed effect. The registry record does not report numerical planning results, and it does not report the observed primary-outcome effect needed to understand such an illustration. The planning assumptions are not evidence that the trial enrolled a sample chosen using that procedure, nor are planning calculations a measure of the study's observed power. Sample-size illustrations describe hypothetical planning conditions; they do not replace the outcome estimate or convey the precision actually achieved.

The primary outcome is marked as having several categories or time points and is not reduced to one comparison. That prevents a single unambiguous primary contrast from being identified in the posted analysis information. In general, multiple endpoints, time points, or contrasts can create multiplicity: the more hypotheses examined, the more opportunity there is for a nominally unusual result to occur by chance. Statistical approaches can address multiplicity, but the registry record does not report whether any such adjustment was planned or used. It also does not state whether one time point had priority over another.

Why do analysis details matter?

An analysis population defines which randomized participants contribute to a particular estimate. Missing outcomes, deviations from assigned treatment, and incomplete follow-up can affect who is included and how results are interpreted. The registry record does not report an analysis population, a missing-data method, or an approach to participants who could not be classified under the abstinence definition. These are important details for interpreting a binary outcome because excluding or classifying participants differently can alter the reported counts and comparison.

The record lists zero analyses and does not give a statistical model or an analysis plan. Thus, general methods such as regression adjustment, covariate selection, or sensitivity analysis cannot be attributed to this study. The appropriate reading is to distinguish the design labels and planning assumptions that are reported from the actual outcome analyses, which are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The record lists three outcome measures and names Self-Control to Resist Smoking and Sleep Efficiency as secondary outcomes. The primary outcome is Smoking Abstinence, with a written definition referring to more than one assessment period. The registry indicates that the primary outcome has several categories or time points and was not reduced to one comparison. It does not report a hierarchy of hypotheses, a designated primary time point for analysis, or a method for adjusting for multiple comparisons. As a general matter, evaluating multiple outcomes or time points can increase the chance of seeing an apparently notable result by chance; multiplicity procedures can address this, but none is described.

Missing-data handling is not reported in the registry record. It does not state how missing smoking-status information was handled, whether participants were classified as smoking when status was unknown, or whether any sensitivity analyses were conducted. The primary outcome's written definition and its 1 Week timeframe label also leave the relationship between the listed timeframe and the stated follow-up assessment unclear. The record does not explain this discrepancy.

The analyzed population is not described. Although enrollment is 19, the record does not provide a participant flow for the primary outcome or state how many randomized participants contributed to an outcome analysis. The adverse-event group denominators are reported separately, but they do not establish the analysis population for smoking abstinence. The registry lists zero analyses and does not report an analysis plan, so the treatment of deviations from assigned counseling or incomplete follow-up is also not reported in 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 5% reporting threshold.

Most frequent non-serious adverse event terms

The registry lists serious adverse events for each arm as counts of affected participants and participants at risk. Cognitive-Behavioral Counseling has 0 serious events among 7 participants at risk; Smoking Cessation Counseling has 0 among 10. Deaths are listed as 0 in both groups. These figures mean that no serious adverse events or deaths are recorded in the listed groups. They do not establish that the risk is absent, particularly because the groups are small and the record does not provide an uncertainty estimate or a comparative safety analysis.

For other adverse events, the record lists 6 affected among 7 at risk in the Cognitive-Behavioral Counseling group and 10 among 10 in the Smoking Cessation Counseling group. These are counts as recorded, not adjusted comparisons. The registry does not specify in the reported information the event types behind those counts, their severity, timing, duration, or relationship to study interventions. The serious-event terms list is empty. The counts should therefore be read as a limited description of reported events, not as evidence that one counseling approach caused more or fewer events than the other.

Safety-event denominators are not the same thing as a primary-outcome analysis population. The record does not explain why the adverse-event denominators are those listed or how they relate to enrollment. No additional denominator or total should be inferred from these figures.

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

The trial's design addresses a focused comparative question: whether Cognitive-Behavioral Counseling or Smoking Cessation Counseling better supports abstinence among smokers with sleep problems when both approaches are paired with nicotine patches. Its randomized, parallel-group structure is relevant to that question, and both interventions are described with the same counseling duration and patch schedule. The record also identifies sleep-related and smoking-related outcomes beyond the primary abstinence measure.

What the record does not establish is the comparative result. It gives no arm-specific smoking-abstinence counts, estimate of effect, confidence interval, or statistical test. Without those results, it is not possible to say which arm had more participants meeting the endpoint, how large any observed difference was, or how uncertain an estimate might be. This limitation is about the registry information available, not a claim that no study data exist elsewhere.

Even if an outcome estimate were available, a result from this pilot would need to be interpreted in light of its enrollment of 19 and the precision of the estimate. A small study may yield uncertain estimates; that general principle does not permit inferring the direction or size of an effect. A planning illustration based on an observed effect would not stand in for a reported result, and planning assumptions do not show the achieved precision.

The safety counts have a separate meaning. They describe recorded adverse events in the listed groups, but they do not answer the abstinence question and do not by themselves establish a difference in safety. Similarly, the existence of secondary outcomes does not tell readers whether those outcomes changed or how they were analyzed. Their results are not reported in the registry record.

The appropriate conclusion is therefore narrow: the registry describes a completed randomized pilot comparing two counseling approaches, each with nicotine patches, and states how abstinence was defined. The posted results do not provide the primary outcome analysis needed to judge the comparison. No claim about whether either counseling approach is more effective, or whether it works, follows from the design description or the adverse-event counts alone.

13. Why This Trial Matters Statistically

This trial is statistically interesting because the treatment contrast is specific. Both arms include behavioral counseling and the nicotine patch, with the same stated session count, treatment duration, timing before quitting, and patch duration. The design therefore focuses the intended comparison on two counseling approaches delivered within a shared treatment structure. That makes a clear definition of the outcome and a clear account of the analyzed comparison especially important.

The primary outcome is a participant count based on smoking status during stated periods. Yet the registry's timeframe label is 1 Week while the operational definition also refers to status at a follow-up visit 4 weeks after treatment. The record does not explain how these details combine into a single analysis endpoint. Further, it notes several categories or time points without reducing them to one comparison. These features illustrate why outcome definitions and analysis priorities matter: an estimate is interpretable only when readers know what was counted and when.

The enrollment of 19 also emphasizes the value of reporting uncertainty, not just a point estimate. In general, estimates from small groups can be imprecise, and confidence intervals help readers assess the range of values compatible with the data. No primary-outcome estimate or confidence interval is reported. The available safety counts are descriptive and do not substitute for an outcome comparison.

Finally, the registry identifies a pilot study but does not report the analysis plan, missing-data approach, or multiplicity strategy. This makes the record useful for understanding the intended design and its reporting gaps, while limiting what can be concluded statistically. The distinction between a study's stated question and its posted analysis is central: design details alone cannot answer an effectiveness question when the relevant results are absent.

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 main limitation for interpreting this trial from the registry record is the absence of reported primary-outcome results. The record does not give smoking-abstinence counts by arm, an effect estimate, a confidence interval, or a p-value. It also lists zero analyses. Thus, the comparative outcome cannot be assessed from the posted registry information, regardless of the study's completed status.

The endpoint has a wording and timing issue: its timeframe is listed as 1 Week, while the operational definition refers both to the last week of treatment and to the last 7 days at the first follow-up visit 4 weeks after treatment. The record does not clarify whether participants must satisfy both conditions, how a single endpoint was constructed, or whether the timeframe label represents only one component. Outcome verification procedures are not reported.

Detailed eligibility criteria and the analyzed population are not reported. The enrollment is 19, but the record does not provide participant flow, arm-specific primary-outcome denominators, attrition, or reasons for missing data. The safety denominators cannot be used to infer the primary-outcome analysis population. Randomization and masking are described by labels, but their practical methods are not reported; the record does not identify who was masked or how assignment was concealed.

The registry does not report the statistical analysis plan, handling of missing outcomes, any adjustment for multiple outcomes or assessment times, or the prioritization of a primary comparison. The record names two secondary outcomes but does not report their results or measurement details. It also gives no numerical result for the planning illustration. These omissions restrict both reproducibility and the ability to judge precision, bias, and the intended scope of inference. They do not establish that such details or analyses were absent from other study materials; they are not reported in the registry record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Smoking Cessation for Smokers With Sleep Problems — NCT01277887.
• Registry record last updated 2017-12-21; status last verified 2017-12.
• Results first posted 2017-12-21.
• 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

The registry record describes a completed randomized, double-masked, parallel pilot with enrollment of 19. It compares Cognitive-Behavioral Counseling with Smoking Cessation Counseling; both approaches involve 8 sessions over 10 weeks, begin 4 weeks before quitting, and include a nicotine patch for 6 weeks from the quit date. The listed start is 2010-12 and primary completion is 2012-03.

The primary outcome is Smoking Abstinence, defined using smoking status during the final week of treatment and at the first follow-up 4 weeks after treatment. The timeframe is listed as 1 Week. Secondary outcomes named are Self-Control to Resist Smoking Cues and Sleep Efficiency. The registry does not report a primary-outcome analysis, outcome counts, or an effect estimate. It also does not report analysis populations, missing-data handling, or a multiplicity approach.

Serious adverse events and deaths are listed as 0 in both arms. Other adverse events are listed for 6 of 7 participants in Cognitive-Behavioral Counseling and 10 of 10 in Smoking Cessation Counseling. These descriptive safety counts do not supply the missing abstinence comparison.