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 Connect to Quit for Smoking (NCT01299896), a randomized na study. The primary outcome is Effectiveness of CTQ vs UC.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01299896 |
| Phase | NA |
| Condition | Smoking, Smoking Cessation |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 633 |
| Arms in the primary outcome | 2 |
| Lead sponsor | University of Pittsburgh |
| Results posted | Yes |
2. Clinical Question
Population
The study concerns low-income veterans who smoke in the regional United States Veterans Administration health care system. The registry describes evaluation in three VA Pittsburgh Healthcare System medical practices. It does not give further eligibility details or a separate description of the population included in the primary outcome analysis; those details are not reported in the registry record.
Intervention
Coordinated Care was the Connect to Quit approach. A coordinator was to coordinate delivery of smoking-related care. The program was described as proactive, personalized and coordinated, and as treating smoking as a chronic condition requiring long-term care that may include behavioral therapy and pharmacotherapy. The registry does not specify the precise services each participant received.
Comparator
Usual Care consisted of care currently offered in the VAPHS, including smoking-cessation medications and in-person or telephone counseling options for quit-smoking classes. The arm description also says that fees incurred by veterans with a co-pay would be reimbursed. The record does not report how often participants used these services.
Primary question
The primary question was whether abstinence differed between participants assigned to Coordinated Care and Usual Care. The endpoint was self-reported abstinence at the end of a two-year period, with self-reports biochemically validated using salivary cotinine <10ng/ml. Abstinence was defined as 30-day point prevalence. The registry reports an abstinence percentage for each arm, but does not report a statistical test or an estimated between-arm comparison.
3. Trial Design
This was a randomized, parallel-group trial with no masking. The registry lists the phase as NA and the status as completed. The study enrollment is recorded as 633. The registry does not describe how the random sequence was generated, how assignments were concealed, or whether any other safeguards were used; those design details are not reported in the registry record.
The two groups were Usual Care and Coordinated Care. In the Coordinated Care arm, a CTQ Coordinator was to coordinate smoking-related care. In Usual Care, participants could continue to access care offered in the VAPHS, including smoking-cessation medications and counseling through in-person or telephone quit-smoking classes. The descriptions establish the intended contrast, but do not show the extent to which care was received or whether participants used services across arms.
The registry gives a study start of 2011-03 and a primary completion date of 2015-02. It describes the evaluation as taking place in three VAPHS medical practices within a regional VA health care system. The primary outcome timeframe is a two-year period, with abstinence assessed at its end. Details such as follow-up visit timing, the precise analysis population, and the handling of participants with no endpoint assessment are not reported in the registry record.
Randomization supports a comparison of assigned groups in principle, but it does not by itself establish how the reported endpoint was analyzed. The registry lists no analyses and does not provide an adjusted or unadjusted treatment-effect estimate, uncertainty interval, or test result. Consequently, the design can be described from the record, while the statistical evidence for a between-arm difference cannot be reconstructed from the posted results.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Usual Care | Coordinated Care |
|---|---|---|
| STARTED | 319 | 314 |
| COMPLETED | 318 | 296 |
| NOT COMPLETED | 1 | 18 |
Reasons for not completing this period:
| Reason | Usual Care | Coordinated Care |
|---|---|---|
| Withdrawal by Subject | 1 | 7 |
| Lost to Follow-up | 0 | 11 |
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.
| Characteristic | Unit | Usual Care | Coordinated Care | Total |
|---|---|---|---|---|
| Participants analysed | 319 | 314 | 633 | |
| Age, Continuous | years | 54.7 (SD 11.5) | 55.7 (SD 8.7) | 55.2 (SD 10.2) |
| Sex: Female, Male: Female | Participants | 28 | 38 | 66 |
| Sex: Female, Male: Male | Participants | 291 | 276 | 567 |
| Region of Enrollment: United States | participants | 319 | 314 | 633 |
6. Primary Endpoint
The registry lists the primary outcome as Effectiveness of CTQ vs UC, measured over Two (2) year period.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percentage of participants per arm |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the percentage of participants per arm who met the study’s definition of abstinence at the end of a two-year period. Abstinence was self-reported as 30-day point prevalence and was to be biochemically validated with salivary cotinine <10ng/ml. Point prevalence refers to status during a specified recent period rather than continuous abstinence throughout follow-up. The registry does not report additional details about how abstinence was assessed or how discordant self-report and cotinine results were handled.
Biochemical validation is used to add an objective check to self-reported smoking status. In general, combining self-report with a biological measure can help distinguish reported abstinence from evidence of recent tobacco exposure. That general rationale does not establish how accurately the endpoint was measured in this study, nor does it establish how missing or inconclusive tests were classified. Those operational details are not reported in the registry record.
The measure is a proportion, so its meaning depends on both the endpoint definition and the participants included in its denominator. The registry describes the unit as a percentage of participants per arm, but does not state whether the displayed arm counts are also the endpoint-analysis denominators. It does not report a confidence interval around either percentage. The posted endpoint therefore describes arm-level abstinence at a specified assessment, not the full course of smoking behavior across the two-year period.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry reports an abstinence percentage of 7.5 for Usual Care and 6.1 for Coordinated Care. The corresponding arm counts listed in the results are 319.0 and 314.0. These are descriptive arm-level results for the primary endpoint, which was 30-day point-prevalence abstinence at the end of a two-year period, biochemically validated using salivary cotinine <10ng/ml.
The reported percentages are numerically higher for Usual Care. That observation alone does not establish that the groups differ beyond what could arise from sampling variation. The registry does not provide a confidence interval, p-value, test statistic, or model-based estimate for the comparison. It also does not provide an analysis population or clarify the denominators used to calculate the percentages. A formal inference about the size or precision of a between-arm difference is therefore not available from the registry record.
The results should not be read as proof that the approaches are equivalent, or as proof that one approach is superior. Establishing equivalence or non-inferiority generally requires a prespecified margin and an analysis designed to address that question; such a margin and analysis are not reported in the registry record. Likewise, a numerical ordering of the arm percentages is not, on its own, a test of a treatment effect.
The record says that values were missing or not estimable for a two-arm comparison for this count-type endpoint. This means the registry does not post a calculated comparison from the arm results. The available percentages can be described, but no recalculated comparison should be substituted for a sponsor analysis: no sponsor comparison is posted. Without an estimate of uncertainty, readers cannot judge how precisely the observed arm percentages distinguish the groups.
In general, a confidence interval conveys a range of effect sizes compatible with the data and the assumptions of the analysis. A narrow interval indicates greater precision than a wide one, while an interval spanning values on both sides of no difference may be consistent with multiple interpretations. No such interval is reported. The safest reading is therefore limited: the registry records two arm-specific endpoint percentages, but does not supply the inferential results needed to assess a between-arm effect.
9. Statistical Methods Explained
What kind of outcome is this?
The primary outcome is a percentage based on an abstinence classification. In general, when an outcome has two categories, such as meeting or not meeting a defined endpoint, an arm-level percentage describes the share classified in the endpoint category among the people included in that calculation. Comparing two such percentages requires a clearly defined denominator for each arm and an explicit method for estimating uncertainty. The registry reports percentages per arm, but does not specify the endpoint-analysis denominators or post a statistical comparison.
The endpoint also depends on a measurement rule: self-reported 30-day abstinence was to be biochemically validated using salivary cotinine <10ng/ml. In general, endpoint definitions matter because a different assessment window or validation rule can classify participants differently. The registry identifies the intended definition but does not describe the detailed procedure for collecting or interpreting the test, handling missing tests, or reconciling test results with self-report.
What can randomization establish?
In general, random assignment aims to make assigned groups comparable at the start of a study, so that differences in later outcomes can be interpreted as evidence about the intervention when the study is conducted and analyzed appropriately. Randomization does not ensure that every participant follows the assigned approach, completes follow-up, or has a measured endpoint. It also does not remove the need to report how the analysis handled departures from assignment or missing outcomes.
This registry identifies the trial as randomized, parallel, and unmasked. It does not report the allocation procedure, concealment method, adherence information, or analysis population. It is therefore possible to describe the randomized design, but not to determine from the record whether the posted arm percentages use an intention-to-treat population, a complete-case population, or another defined set of participants. Those choices can affect how an endpoint comparison should be interpreted.
Why is a confidence interval useful?
In general, an estimate based on a sample has sampling uncertainty. A confidence interval expresses that uncertainty around an estimated quantity, such as a difference between arm percentages. The interval helps distinguish the point estimate from its precision: two studies can have similar point estimates but different precision. A p-value, when reported, addresses a different question under a specified statistical model and null hypothesis; it does not describe the size of an effect or replace an interval.
No confidence interval, p-value, or test statistic for the primary comparison is reported in the registry record. No adjusted model is reported either. The two arm percentages alone do not provide a basis for assigning a level of statistical significance or for making a precise claim about the comparative effect. The registry also does not report covariate adjustment or the rationale for any analysis choice.
What do the planning illustrations represent?
In general, sample-size calculations ask how many participants would be needed under stated assumptions to detect a chosen effect with a specified probability, conditional on a statistical model and design. The planning illustrations associated with these results are described as being based on the observed effect, with a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. They consider effects expressed as a stated fraction of the observed effect. These are planning scenarios, not evidence that the trial had a particular probability of detecting an effect.
The registry does not report the trial’s own sample-size justification, so the planning illustrations should not be treated as the protocol’s design calculation. They are not observed power and do not establish whether the trial was adequately sized. A calculation based on a result observed in the same study is also a retrospective planning illustration, not independent confirmation of the result. The numerical assumptions do not replace a trial-specific analysis or account for unreported details such as endpoint missingness and the analysis population.
Why might a count comparison be unavailable?
In general, a two-arm comparison of proportions requires an explicit estimand, denominators, and a statistical method. Different valid methods may address different questions, including a difference in percentages, a relative measure, or an adjusted contrast. Their uncertainty estimates can also depend on the analysis population and model assumptions. The registry indicates that a comparison was not estimable for this count-type outcome and posts no analyses. It does not explain the technical reason beyond that status, so a more specific explanation would be speculative.
The endpoint is not a time-to-event outcome: it is an abstinence status assessed at a stated time. Thus, the general purpose of time-to-event methods—using information about when an event occurs and accounting for follow-up duration—does not describe the primary measure as defined in the registry. No survival analysis is reported for this endpoint. The interpretation should remain tied to the posted arm percentages and the absence of a formal comparison.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one primary outcome measure and no secondary outcomes posted. It records no analyses. This limits what can be assessed about the study’s statistical reporting: the record does not show a family of reported outcome tests, but it also does not provide a complete statistical analysis plan or a statement about multiplicity control. Whether any multiplicity strategy was planned or used is not reported in the registry record.
Multiplicity refers, in general, to the increased chance of at least one false-positive finding when several hypotheses are tested. How it should be handled depends on the number and structure of planned comparisons and on which outcomes are confirmatory. The posted record is not sufficient to determine the full set of planned analyses or whether there were additional comparisons outside the posted results. No claim about multiplicity adjustment can therefore be made.
The registry does not describe how missing endpoint data were handled, how many participants lacked an endpoint assessment, or whether imputation or another method was used. It also does not identify the population used for the primary outcome analysis. These omissions matter because the interpretation of an arm percentage depends on who was included and how missing outcomes were classified. The record does not report interim analyses, stopping rules, or a detailed statistical analysis plan. Those details should not be inferred from the randomized design or from the arm-level percentages.
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 |
|---|---|---|---|
| Usual Care | 181 | 319 | 56.7% |
| Coordinated Care | 175 | 314 | 55.7% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Usual Care | 0 of 319 |
| Coordinated Care | 0 of 314 |
Most frequent serious adverse event terms
| Event term | Organ system | Usual Care | Coordinated Care |
|---|---|---|---|
| Hospitalization | General disorders | 157 of 319 | 162 of 314 |
| Death | General disorders | 24 of 319 | 13 of 314 |
Serious events with the highest arm-level rate: hospitalization (51.6%), death (7.5%).
The registry records serious adverse events for both arms. The serious-event group entries list 319 at risk and 181 affected in Usual Care, and 314 at risk and 175 affected in Coordinated Care. These figures describe the registry’s serious-event reporting; they do not, by themselves, establish that an event was caused by the assigned care. The record does not provide a treatment-relatedness assessment or a comparative safety analysis.
The most frequently listed serious-event terms are Hospitalization at 51.6% and Death at 7.5%. The registry does not give further detail in these entries about the timing, duration, causes, or distribution of the events across individuals. The separate death-count fields are not reported in the registry record, so the serious-event term percentage should not be treated as a separate death count or as a comparison of mortality between arms.
In general, adverse-event summaries need context about definitions, follow-up, and whether the figures count participants, events, or both. The entries identify serious events and their associated terms, but the record does not give enough detail to infer comparative risk or attribution. Other adverse events are listed as zero affected in each arm; that registry entry should not be extended to outcomes or event categories not reported there.
12. What the Result Does, and Does Not, Mean
The results establish that the registry records arm-level percentages for the prespecified abstinence endpoint: 7.5 for Usual Care and 6.1 for Coordinated Care. The endpoint is specifically 30-day point-prevalence abstinence at the end of a two-year period, with self-reported abstinence to be biochemically validated using salivary cotinine <10ng/ml. These figures are descriptive results under that definition.
They do not establish a statistically reliable difference between the assigned approaches. No comparison estimate, confidence interval, or test result is posted, and the registry states that a two-arm comparison was not estimable for this count-type outcome. The numerical ordering of percentages does not settle whether there is a real group difference, how large it might be, or how precisely it has been estimated.
The endpoint does not represent continuous abstinence throughout the follow-up period. It captures reported abstinence over the stated recent period at the end of the two-year timeframe. The registry does not report the number with missing assessments, the denominator used for each percentage, or how missing or discordant validation results were handled. These gaps constrain interpretation of the percentages.
Nor do the results show how consistently participants received the coordinated intervention, how much usual-care support was used, or whether the intervention changed access to particular services. The descriptions explain the planned care contrast, not actual exposure. The record also does not report outcomes beyond the primary measure or a detailed analysis plan. The finding should therefore be read narrowly as a pair of posted percentages without an inferential comparison, rather than as a definitive conclusion about effectiveness, equivalence, or the broader consequences of either care approach.
13. Why This Trial Matters Statistically
This trial is statistically notable for the distinction between an arm-level result and a comparative result. A percentage in each randomized group can describe the observed endpoint, but a treatment comparison requires an estimate of the contrast and its uncertainty. The registry reports the former and does not provide the latter. Keeping those two levels of evidence separate avoids treating a numerical ordering as a tested treatment effect.
The endpoint also illustrates why a clinical outcome must be read together with its operational definition. The result concerns 30-day point-prevalence abstinence at the end of a two-year period, not a report of uninterrupted abstinence over the entire period. The biochemical validation threshold is part of that definition. Without details on assessment and missing-result handling, readers should not assume a broader measure than the one described.
Finally, the record demonstrates the limits of registry results for assessing statistical precision. No confidence interval, p-value, or analysis is posted for the primary comparison, and the record notes that a two-arm comparison was not estimable. The randomized design is important context, but it cannot substitute for transparent reporting of the estimand, denominator, analysis population, and uncertainty. These distinctions are relevant to researchers evaluating what can—and cannot—be learned from a completed trial record.
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 statistical interpretation is the absence of a reported between-arm estimate and its uncertainty. The registry provides two arm-level endpoint percentages, but no confidence interval, p-value, test statistic, or model. It explicitly indicates that a two-arm comparison was not estimable for this count-type endpoint. The posted results therefore cannot support a precise inference about the magnitude or uncertainty of the contrast.
The registry does not identify the denominator used for each percentage or the population included in the endpoint analysis. Although arm counts are listed, the record does not say whether they are the analysis denominators. Missing endpoint counts, missing-data methods, and the handling of unvalidated or discordant abstinence reports are not reported in the registry record. Each of these can affect the meaning of an arm-level percentage.
Intervention delivery and usual-care use are also not described in enough detail to assess exposure. The record gives brief arm descriptions but no adherence, uptake, or crossover results. It does not report the randomization method, allocation concealment, a detailed analysis plan, or the trial’s sample-size rationale. The planning illustrations based on the observed effect do not fill that gap.
There are no secondary outcomes or analyses posted in the registry. The available record consequently offers limited information about outcome breadth, multiplicity, and possible prespecified subgroup analyses. These are limits of the registered results available for interpretation; they do not establish what analyses or procedures may have been documented elsewhere.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Connect to Quit for Smoking — NCT01299896.
- Registry record last updated 2016-03-22; status last verified 2016-02.
- Results first posted 2016-02-24.
- 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
NCT01299896, titled Connect to Quit for Smoking, is a completed randomized, parallel-group trial with no masking. It evaluated Coordinated Care against Usual Care among low-income veterans in three VAPHS medical practices. Enrollment is recorded as 633, with a study start of 2011-03 and primary completion of 2015-02.
The primary endpoint was 30-day point-prevalence abstinence at the end of a two-year period, based on self-report with biochemical validation using salivary cotinine <10ng/ml. The registry reports arm-level percentages of 7.5 for Usual Care and 6.1 for Coordinated Care. It does not post a statistical comparison, uncertainty interval, or analysis population, and indicates that a two-arm comparison was not estimable for this endpoint. Serious-event terms and affected counts are also recorded, but no comparative safety analysis is reported.