Innovative Digital Therapeutic for Smoking Cessation: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Innovative Digital Therapeutic for Smoking Cessation (NCT03694327), a randomized na study. The primary outcome is 30-Day Sustained Abstinence From Smoking.

2. Clinical Question

The registry identifies the primary outcome as 30-Day Sustained Abstinence From Smoking. Its description says abstinence was self-reported in the 8-Week Outcome Survey. The record does not report a result for that outcome, so the comparison between the apps cannot be quantified from the registry information.

The study title refers to biochemical verification, and a secondary outcome concerns the feasibility of biochemical verification of smoking cessation. The primary-outcome description, however, specifies self-report; it does not say that the primary outcome was biochemically confirmed. The record also lists use of nicotine replacement therapy and smoking-cessation pharmacotherapy as a secondary outcome.

3. Trial Design

This was a randomized, double-masked, parallel-group study comparing two smartphone applications for smoking cessation. The registry describes random allocation in a 1:1 ratio. In a parallel design, participants are assigned to one intervention group rather than crossing between interventions. The record does not identify which people or study roles were masked.

The two groups were Treatment A (CT-101-M) and Treatment B (QuitGuide). Both were described as smartphone applications designed to assist with smoking cessation. The registry lists the study phase as NA and its status as completed. Enrollment is recorded as 158. The sponsor is My Digital Study.

The study population was US participants, male or female, ages 18 to 65, who smoked at least 5 cigarettes per day and were interested in quitting within the next 30 days. The population description is incomplete in the registry record after that eligibility information, so additional eligibility details cannot be established from it.

The primary outcome was assessed upon completion of an 8-week period. The record gives a start date of 2018-10-24 and a primary completion date of 2019-03-14. It lists three outcome measures, including the primary abstinence measure and two secondary outcomes: feasibility of biochemical verification and use of nicotine replacement therapy and smoking-cessation pharmacotherapy. The registry record lists no analysis entries. It does not report the protocol’s statistical plan, sample-size justification, or procedures for handling missing outcomes.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The study population was randomized 1:1 across Treatment A (CT-101-M) and Treatment B (QuitGuide). The population enrolled was US only, male or female, ages 18 to 65, and smoke at least 5 cigarettes per day with an interest in quitting smoking within the next 30 days. Participants enrolled had not used Clickotine or QuitGuide; and were not using an NRT at the time of enrollment

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: The population enrolled was US only, male or female, ages 18 to 65, and smoke at least 5 cigarettes per day with an interest in quitting smoking within the next 30 days. Participants enrolled had not used Clickotine or QuitGuide; and were not using an NRT at the time of enrollment.

6. Primary Endpoint

The registry lists the primary outcome as 30-Day Sustained Abstinence From Smoking, measured over Upon completion of 8-week period.

The primary endpoint is titled 30-Day Sustained Abstinence From Smoking and is expressed as a count of participants. Its description states that self-reported abstinence was assessed in the 8-Week Outcome Survey, with the assessment made upon completion of the 8-week period. The endpoint therefore concerns participants’ reports of abstinence, rather than a continuous measurement of smoking behavior.

A binary outcome classifies each participant into one of two states for the specified measure, such as meeting or not meeting an abstinence definition. Counts can then describe how many participants in each group met the endpoint. A comparison of those counts can be informative, but interpreting it also requires knowing the group denominators, the precise endpoint definition, and the uncertainty around the estimated difference or relative contrast.

The registry record does not explain how the 30-day period was defined, what counted as a lapse, or how survey nonresponse was handled. It also does not report the primary-outcome counts or a comparison between groups. Although biochemical verification appears in the study title and as a secondary outcome, the primary endpoint description specifies self-report and does not state that it was biochemically confirmed.

Abstinence is used as an outcome because it directly represents the behavior the interventions are intended to address. Self-report allows that behavior to be assessed through a survey, but it is not interchangeable with biochemical confirmation. The registry record does not report whether or how the verification measure was applied to the primary endpoint.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does randomization contribute?

Randomization assigns participants to study groups using a chance-based process. Its purpose is to reduce systematic differences between groups at assignment, including differences that researchers may not have measured. It does not ensure perfect balance in every characteristic, and it cannot correct problems that arise after assignment, such as missing outcome data or departures from the planned procedures. The registry labels this study randomized and states that allocation was 1:1. It does not report the randomization sequence method, concealment procedures, or whether assignment was stratified.

How should a binary outcome be compared?

A binary outcome records whether each participant meets a defined condition. For this trial, the primary outcome is a count of participants with reported abstinence, assessed in the 8-Week Outcome Survey. A descriptive analysis could report the count and denominator in each group. A comparative analysis might estimate an absolute difference in the proportions meeting the endpoint or a relative contrast. These are general examples of ways binary outcomes can be analysed, not claims about the analysis performed in this trial. The registry record does not report a primary-outcome analysis or specify the method used.

Interpretation depends on the endpoint definition as well as the counts. A reproducible analysis needs to state how the abstinence period is defined, how the survey response is classified, and how missing responses are treated. The record gives the endpoint title and survey timing but does not report those operational details. It also does not state whether the primary endpoint was confirmed biochemically; its description specifies self-report.

What do uncertainty measures add?

An effect estimate gives the direction and size of a contrast under the chosen definition. A confidence interval communicates the range of values compatible with the observed data under the model and its assumptions. A narrow interval indicates greater precision than a wide interval, while neither width nor the point estimate alone establishes practical importance. A hypothesis test and its p-value address a related but different question: how compatible the data are with a specified null hypothesis under the model. These measures should be considered alongside the endpoint definition and the design, rather than as stand-alone verdicts.

No primary-outcome effect estimate, confidence interval, or p-value is reported in the registry record. The record lists no analysis entries, so it is not possible to identify which estimator, model, or inferential procedure was used. The sponsor’s analysis, if reported elsewhere, cannot be reconstructed from the registry entries alone.

Why does the analysis population matter?

A trial analysis should make clear which participants are included and how assignment is handled. An intention-to-treat approach generally analyses participants in the groups to which they were randomized, regardless of later adherence. Other analysis populations can answer different questions and may introduce selection concerns if inclusion depends on events after randomization. These are general methodological considerations. The registry record does not report the analysis population used for the abstinence endpoint or how withdrawals and missing surveys were handled.

Missing outcomes matter because a participant with no recorded survey response cannot automatically be classified as abstinent or not abstinent without an explicit rule. Different assumptions about missing responses can alter an estimate. Sound reporting describes the amount and pattern of missingness, the primary handling method, and any sensitivity analyses. None of those details is reported in the registry record.

How should planning calculations be read?

The record describes sample-size assumptions for planning illustrations based on the observed effect: a two-sided significance level of 0.05, equal allocation between the arms, and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect. Such a calculation is conditional on its assumptions and is a planning illustration, not observed power. It does not show that the trial was designed around that effect, nor does it replace an analysis of the trial’s actual outcomes. The registry record does not report the trial’s own sample-size justification.

For binary outcomes, the precision of a comparison depends on the event counts and denominators as well as the model and endpoint definition. A planning calculation cannot establish the precision of an unreported result. The registry record does not provide primary-outcome counts or analysis estimates from which to assess that precision.

What about over-dispersion and repeated measurements?

Over-dispersion is a general concern when observed variability exceeds what a statistical model assumes. It can make standard errors too small if the model does not allow for the extra variability. It is most relevant for certain count or clustered-data models; it is not a reason by itself to select a particular method for a binary endpoint. Repeated measurements may also require methods that account for within-participant dependence. The registry record does not describe repeated primary-outcome measurements, a count model, or any adjustment for over-dispersion. These general considerations should not be mistaken for details of the trial’s analysis.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists three outcome measures, including 30-Day Sustained Abstinence From Smoking and the secondary outcomes of feasibility of biochemical verification and use of nicotine replacement therapy and smoking-cessation pharmacotherapy. Testing several outcomes or several versions of an outcome can increase the chance of finding an apparently notable result by chance. A statistical plan may identify a primary endpoint, define the order of testing, or adjust inference for multiple comparisons. The registry record does not report a multiplicity strategy or a detailed statistical analysis plan.

The record does not report the primary-outcome counts or analysis. It also does not report missing survey counts, reasons for missingness, imputation procedures, or sensitivity analyses. These omissions matter because the interpretation of a binary endpoint depends on how participants without an observed response are treated. The endpoint description identifies a survey assessment but does not say how nonresponse affected classification.

The registry record lists no analysis entries and does not specify the analysis population. It therefore does not establish whether the reported primary analysis, if any, followed randomized assignment, included only participants with observed surveys, or used another population. These are distinct analysis choices, and the record does not support selecting among them. The information available is insufficient to determine how multiplicity or missing data influenced any estimate.

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 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: diabetic ketoacidosis (1.3%).

For serious adverse events, the registry records 0 of 79 participants at risk in Treatment A (CT-101-M) and 1 of 79 in Treatment B (QuitGuide) as affected. For other adverse events, it records 11 of 79 in Treatment A and 5 of 79 in Treatment B. Deaths are recorded as 0 in each group. The listed top serious-event term is Diabetic Ketoacidosis, with 1.3% reported.

These are descriptive counts. A count of affected participants does not show whether an event was caused by an app, nor does a difference in counts by itself establish a safety difference. Interpretation depends on event definitions, follow-up, completeness of reporting, and the analysis method. The registry record does not provide a comparative safety analysis, details about event severity beyond the serious-event classification, or information establishing causality. The counts should therefore be read as the adverse-event information recorded, not as proof for or against a causal effect.

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

The registry record establishes that a randomized, double-masked, parallel-group study compared CT-101-M with QuitGuide and assessed self-reported abstinence at completion of an 8-week period. It also records serious and other adverse-event counts. Those design and safety details describe the study, but they do not answer whether the apps differed on the primary outcome.

The primary-outcome result is not reported in the registry record. There is no reported count of participants meeting the endpoint by group, no comparative estimate, and no uncertainty measure. It is therefore not possible to judge the direction, size, or precision of a difference in abstinence from the registry record. The absence of a reported result should not be interpreted as evidence that the groups were equal, or as evidence that either app did or did not affect cessation.

The title mentions biochemical verification, and feasibility of biochemical verification is listed as a secondary outcome. The primary-outcome description says that abstinence was assessed by self-report. The record does not report whether biochemical verification was completed, how it was conducted, or how it related to the primary endpoint. This distinction matters because self-report and biochemical assessment are different measurement approaches.

The planning assumptions described in the record concern illustrative calculations based on the observed effect. Such calculations are not observed power and do not establish the strength of the trial’s result. A result’s interpretation requires the outcome data, the analysis method, and its uncertainty, as well as clarity about missing responses and endpoint definitions. Those details are not reported in the registry record. The posted information supports describing the trial’s design and recorded adverse events, but not a conclusion about comparative efficacy.

13. Why This Trial Matters Statistically

This trial raises statistical questions that are common in digital-intervention research. Randomized comparisons can help separate an intervention contrast from some forms of baseline selection, but their usefulness depends on clear outcome measurement and transparent reporting. Here, the stated primary outcome combines a behavioral concept—30-day sustained abstinence—with a self-reported survey assessment at the end of an 8-week period. Readers need the classification rules and the observed results to understand what the comparison estimates.

The title’s reference to biochemical verification alongside a self-reported primary outcome also highlights the importance of distinguishing outcome measurement from outcome verification. A secondary outcome addresses feasibility of biochemical verification, but its result is not reported in the registry record. Without those findings, the record cannot show how verification performed or whether it changed interpretation of the self-reported outcome.

The registry identifies a head-to-head comparison of two digital interventions and lists the population and design. It does not report the primary analysis, uncertainty, missing-data handling, or multiplicity plan. These are not minor technical details: they determine how an estimate should be interpreted and how robust it may be to assumptions. The example underscores why registration details and results reporting serve different purposes. A design description can establish what was intended to be studied, while outcome results and methods are needed to assess what the study found.

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 does not report primary-outcome counts or a comparison between the app groups. This is the central limitation for interpreting the trial’s smoking-cessation question. No estimate or uncertainty measure is available in the record, so the direction, magnitude, and precision of any primary-outcome difference cannot be assessed.

The primary outcome is described as self-reported abstinence assessed in the 8-Week Outcome Survey, but the operational definition of 30-Day Sustained Abstinence is not reported. The record does not explain how lapses, incomplete surveys, or missing responses were classified. Although biochemical verification appears in the title and as a secondary outcome, the record does not describe whether verification was used to confirm the primary endpoint or provide its results.

The registry lists no analysis entries. The statistical analysis plan, analysis population, multiplicity approach, and missing-data procedures are not reported in the registry record. Without these details, readers cannot determine how the planned comparison was carried out or evaluate the sensitivity of any result to analysis choices.

The stated population is restricted to US participants, male or female, ages 18 to 65, who smoked at least 5 cigarettes per day and were interested in quitting within the next 30 days. The registry’s population description is incomplete after those criteria, so additional selection requirements are unclear. These eligibility details limit how broadly the study population can be characterized. The record also does not provide results for its secondary outcomes, including feasibility of biochemical verification and pharmacotherapy use.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Innovative Digital Therapeutic for Smoking Cessation — NCT03694327.
• Registry record last updated 2022-06-06; status last verified 2022-05.
• Results first posted 2022-06-06.
• 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

NCT03694327 is a completed randomized, double-masked, parallel-group study sponsored by My Digital Study. It enrolled 158 participants and compared the CT-101-M and QuitGuide smartphone applications. The registry describes a US population of male or female participants, ages 18 to 65, who smoked at least 5 cigarettes per day and were interested in quitting within the next 30 days.

The primary outcome was titled 30-Day Sustained Abstinence From Smoking and was assessed by self-report in the 8-Week Outcome Survey upon completion of an 8-week period. The registry lists feasibility of biochemical verification and nicotine replacement therapy and smoking-cessation pharmacotherapy use as secondary outcomes. The record lists no analysis entries and does not report the primary-outcome result or a statistical comparison between the apps. Serious and other adverse-event counts are recorded, but they do not establish comparative efficacy or causality.