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 Automated Reinforcement Management System (ARMS) (NCT04656925), a na na study. The primary outcome is Biochemically Measured Change in Alcohol Abstinence..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04656925 |
| Phase | NA |
| Condition | Alcohol Use Disorder |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 12 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Washington State University |
| Results posted | Yes |
2. Clinical Question
Population
The study enrolled 12 participants with alcohol use disorder. The registry describes a within-participant design: each participant was intended to take part in all three phases. It does not report further eligibility details or participant characteristics in the record.
Intervention
The intervention was behavioral contingency management. The study description proposed an integrated system that could use smartphone input, ecological momentary assessments, geospatial mapping, and feedback from a portable biomarker-measuring device. The record identifies the intervention as contingency management but does not report detailed implementation results.
Comparator
The comparison was within the same participants across phases, not between separately randomized groups. The first A phase and second A phase were designated control or baseline observation periods; the B phase was designated the experimental period. Allocation is listed as NA, and the record does not describe a randomized comparison.
Primary question
The primary outcome was the number of negative breath alcohol concentration samples by phase. Samples were scheduled three times daily during an eight-week sequence: two weeks in the first A phase, four weeks in the B phase, and two weeks in the second A phase. The question was whether biochemically measured abstinence, as represented by negative samples, changed across these phases. Numerical phase results and an inferential analysis are not reported in the registry record.
3. Trial Design
ARMS is a completed, single-group study sponsored by Washington State University. The official title identifies it as a Phase I study, while the phase field is listed as NA. The registry records enrollment of 12 participants, no masking, and a single-group model. Allocation is listed as NA, so the record does not describe random assignment to competing treatment groups.
The study used an A-B-A sequence. Each participant was to experience a first A phase, a B phase, and a second A phase. The first and second A phases were described as control or baseline observation periods, while B was the experimental period. The primary outcome timeframe was daily during eight weeks: two weeks in the first A phase, four weeks in B, and two weeks in the second A phase. Breath samples were submitted three times daily.
This structure allows observation of measurements from the same participant in different phases. It is not equivalent to a randomized parallel-group comparison: all participants went through the same stated sequence, and the order of phases was not randomized in the record. Consequently, differences across phases could reflect the intervention period, but the design alone cannot separate that possibility from other changes over time or effects of being observed. The registry does not report a protocol for handling such influences.
The registry lists feasibility of app usage and treatment retention as secondary outcomes. It records the study as completed, but numerical primary or secondary outcome results and analysis entries are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Contingency Management A-B-A |
|---|---|
| STARTED | 12 |
| COMPLETED | 10 |
| NOT COMPLETED | 2 |
Analysis population for the primary outcome, as defined in the registry: This is a within subject design (each participant goes through all three phases, the two A phases are control phases and B is the experimental phase). The overall number of units is total BAC submission for all phases. The numbers analyzed below differ based on total number of samples submitted by phase.
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 | Contingency Management A-B-A |
|---|---|---|
| Participants analysed | 12 | |
| Age, Continuous | Years | 39.5 (SD 8.6) |
| Sex: Female, Male: Female | Participants | 3 |
| Sex: Female, Male: Male | Participants | 9 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 12 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 12 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 12 |
| Employment: Employed | Participants | 9 |
| Employment: Unemployed | Participants | 3 |
| Baseline EtG Result: Positive | Participants | 11 |
| Baseline EtG Result: Negative | Participants | 1 |
6. Primary Endpoint
The registry lists the primary outcome as Biochemically Measured Change in Alcohol Abstinence., measured over Daily during 8 weeks (2 weeks of first A phase, 4 weeks of B phase, and 2 second A phase).
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Number of negative BAC samples by phase. |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was the number of negative BAC samples by phase. BAC refers to breath alcohol concentration in the outcome description; the measure used breath samples submitted three times daily. A negative sample is the endpoint’s biochemical indicator of abstinence at the time the sample was collected. Counting negative samples captures repeated observations over the study phases rather than relying only on a participant’s retrospective report.
The outcome was assessed during the first A phase, the B phase, and the second A phase. The registry describes these as two baseline observation periods around an experimental period. Because this is a count, its interpretation depends on how many samples were submitted: the record explicitly notes that the numbers analyzed differ based on the total number of samples submitted by each participant. A count of negative samples is therefore not, by itself, a common-denominator rate of abstinence unless the number of submitted samples is also considered.
Repeated biochemical measurements can provide evidence about observations at sampled times, but they do not establish behavior at every time between samples. The registry does not report numerical counts by phase, a denominator for each phase, a summary measure of change, or an inferential result. The intended endpoint is described, but its observed magnitude and precision are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes the question and measurement schedule, but does not report the primary endpoint values or an analysis of change across phases. It is therefore not possible to characterize the direction, size, or precision of any change in negative BAC samples from the registry record. The record also lists zero analysis entries. This means the design description should not be mistaken for a reported result.
The study’s within-participant structure means that each participant serves as their own source of observations across the A-B-A sequence. In general, this can reduce the influence of stable differences between people when comparing their measurements over time. However, measurements within one person are related, and the phase sequence also follows time order. General statistical interpretation therefore needs to account for repeated observations and the possibility that time-related changes coincide with the B phase. The registry does not report whether or how these issues were addressed.
Counts of negative samples must be interpreted alongside the number of samples submitted. The record notes that the numbers analyzed differ according to each participant’s total submitted samples. If participants contribute different numbers of observations, raw counts can reflect both the frequency of negative samples and the number of opportunities to observe them. The record does not report phase-specific denominators or a method for accounting for variation in submissions.
The adverse-event entries are descriptive safety counts by phase, not evidence about the primary abstinence outcome. They list no serious adverse events and no deaths in the three phases, with other adverse events recorded in the first A and B phases. These entries do not supply an estimate of intervention effect, and the record does not explain whether the same participants contributed across more than one phase.
Any planning illustration based on an observed effect should be understood as a hypothetical planning exercise, not as observed power or as part of the trial’s documented design. The registry does not report a sample-size justification, a statistical analysis plan, or the outcome estimate on which such an illustration could be evaluated. Overall, the available record supports description of the design and intended endpoint, but not a conclusion about the observed primary outcome.
9. Statistical Methods Explained
The primary measure is a count: the number of negative BAC samples in each phase. A count records how many qualifying observations occurred, rather than the average value of a continuous measurement. In this study, the qualifying observations were breath samples classified as negative. The registry does not report the numerical counts, the number of samples submitted in each phase, or the precise rule used to classify a sample as negative.
General explanation: counts are often influenced by exposure, meaning the number of opportunities for an event to be recorded. Here, a participant who submits more samples has more opportunities to contribute negative samples. Comparing raw counts can therefore mix two features: how often submitted samples are negative and how many samples were submitted. A statistical analysis might account for the number of observations or analyze a proportion, but the registry does not report which approach, if any, was used. No new rate or denominator can be derived from the record.
The repeated-measures structure also matters. Observations from one participant are generally not independent of one another: a participant’s measurements may share characteristics that differ from those of other participants. General explanation: an analysis that treats every sample as if it came from a different, unrelated person can understate the dependence among observations and give misleading uncertainty. Methods for repeated data can model within-person correlation or summarize each participant’s outcomes by phase. The registry does not report an analytic method, model, or variance estimate.
The outcome is a count, so the distribution of counts is another methodological consideration. General explanation: a basic count model often assumes a particular relationship between the mean and variability. When counts vary more than that assumption allows, over-dispersion can make standard errors too small if it is ignored. Other features, such as many zero counts or unequal numbers of submitted samples, may also matter. The record does not report distribution checks, an over-dispersion assessment, or a model choice, so none should be attributed to this study.
The A-B-A sequence creates a phase comparison within participants, but phase is also ordered in time. General explanation: an observed difference between A and B can be associated with the B period without proving that the intervention alone caused the difference. Changes over time, carryover, or measurement behavior could also affect phase observations. The later A phase may help describe whether the sequence of measurements changed after B, but it does not create an independent randomized control group. The registry does not report methods for separating intervention effects from these possible influences.
For an estimate to be interpreted, its uncertainty is also important. General explanation: a confidence interval describes a range of values compatible with the data and the assumptions of the analysis, and conveys precision as well as the estimated effect. A p-value, when reported, addresses compatibility with a specified null model under its assumptions; it is not a measure of clinical importance or the probability that a hypothesis is true. No primary estimate, confidence interval, p-value, or other inferential result is reported in the registry record.
The registry lists one primary outcome and two secondary outcomes: feasibility of app usage and treatment retention. General explanation: when several outcomes or comparisons are tested, the chance of at least one apparently notable finding can increase if multiplicity is not addressed. An analysis plan may specify a primary outcome, adjustment procedures, or a hierarchy of tests. The record does not report such procedures or identify analyses for the outcomes.
Planning calculations are distinct from trial results. The record describes planning illustrations based on a fraction of an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It specifies that such illustrations are not the trial’s own design and that participant counts are per arm for non-time-to-event outcomes. This study is described as a single-group, within-participant sequence, so those assumptions should not be mistaken for its observed design. A planning illustration is not observed power; the registry does not report a sample-size justification for the study.
In short, the record defines a repeated count outcome and an A-B-A sequence, but does not document the statistical model, handling of participant-level dependence, missing submissions, covariates, confidence intervals, or hypothesis tests. Those details are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists the number of negative BAC samples by phase as the primary outcome, with feasibility of app usage and treatment retention as secondary outcomes. It also records three outcome measures in total. The registry does not report which secondary measures were analyzed, whether there were additional comparisons within an outcome, or whether any multiplicity procedure was planned. No analysis entries are recorded.
General explanation: when several outcomes, time points, or contrasts are examined, multiple testing can make apparently unusual results more likely to arise by chance. A prespecified primary outcome can help distinguish the central question from secondary or exploratory questions, but that distinction does not by itself reveal whether analyses were adjusted or how results should be interpreted. The record does not report an analysis hierarchy or adjustment strategy.
Missingness is particularly relevant because the primary outcome is based on submitted samples. The outcome description says that the numbers analyzed differ according to the total number of samples each participant submitted. The record does not report how many samples were expected or received by phase, why samples were not submitted, or whether missing samples were excluded, imputed, or handled in another way. It also does not describe a rule for including participants in each analysis.
The registry identifies 12 enrolled participants and describes a within-participant design in which participants go through all three phases. It does not report phase-specific analysis populations, participant-level completion counts, or whether every enrolled participant contributed measurements to every phase. Thus, enrollment should not be treated as the number of observations available for each phase. The registry record does not report the analysis population or missing-data method.
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 |
|---|---|---|---|
| First A Phase | 0 | 12 | 0.0% |
| B Phase | 0 | 12 | 0.0% |
| Second A Phase | 0 | 12 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| First A Phase | 0 of 12 |
| B Phase | 0 of 12 |
| Second A Phase | 0 of 12 |
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 |
|---|---|
| First A Phase | 2 of 12 |
| B Phase | 2 of 12 |
| Second A Phase | 0 of 12 |
Most frequent non-serious adverse event terms
| Event term | Organ system | First A Phase | B Phase | Second A Phase |
|---|---|---|---|---|
| Kidney Pain | Renal and urinary disorders | 1 of 12 | 0 of 12 | 0 of 12 |
| Mild headache | Nervous system disorders | 1 of 12 | 0 of 12 | 0 of 12 |
| Sleep apnea | Respiratory, thoracic and mediastinal disorders | 0 of 12 | 1 of 12 | 0 of 12 |
| Shoulder pain | Musculoskeletal and connective tissue disorders | 0 of 12 | 1 of 12 | 0 of 12 |
The registry lists serious adverse events for each phase. For the first A phase, B phase, and second A phase, 12 participants are listed as at risk, and zero as having a serious adverse event. Deaths are also listed as zero in each phase. For other adverse events, 12 participants are listed as at risk in each phase; two are listed as affected in the first A phase, two in the B phase, and zero in the second A phase.
These are phase-specific descriptive entries. They do not provide event rates, comparative risk estimates, or a test of differences, and the record does not report details about the other adverse events. Because the same participants experienced the phases in sequence, the entries should not be read as counts from three independent groups. The registry does not report whether the same participants were affected in more than one phase, the severity or nature of the other events, or the method used to collect safety information.
The zero serious-event entries describe what is recorded for these phases; they do not establish that no unrecorded event occurred or that the study can rule out uncommon harms. The record does not report a separate safety analysis.
12. What the Result Does, and Does Not, Mean
The registry record establishes that ARMS was completed as a single-group study with 12 enrolled participants and an A-B-A phase sequence. It identifies a primary outcome based on negative breath alcohol concentration samples and describes the timing and frequency of sample submission. It also lists app usage feasibility and treatment retention as secondary outcomes.
Those design details do not establish what happened to the primary outcome. Numerical phase counts, submission denominators, effect estimates, uncertainty intervals, and hypothesis tests are not reported in the registry record. Accordingly, the direction and size of change in biochemically measured abstinence cannot be described from these entries. It would be inappropriate to infer a benefit or lack of benefit from the design or from the safety counts.
General explanation: a within-participant sequence can be useful for observing how measurements vary across periods in the same people. It is not the same as a randomized comparison, and a change occurring during an intervention phase is not, by itself, proof that the intervention caused it. Time trends, changes in sample submission, and other influences may coincide with the phase sequence. The registry does not report an analysis that addresses these considerations.
The sample submission process also affects what the primary count represents. Negative samples are observations at particular times, not a continuous record of drinking behavior between samples. Different numbers of submitted samples can make raw counts difficult to compare unless the analysis accounts for the number of observations. The registry notes that analyzed numbers differ based on sample submissions, but does not report how those differences were handled.
The record’s adverse-event counts are limited descriptive information. They show zero serious adverse events and zero deaths listed in each phase, and some other adverse events in two phases. They do not establish comparative safety or provide detail about event types. The record supports conclusions about the study’s stated structure and recorded counts, but not a claim about treatment efficacy, causal effect, or complete safety.
13. Why This Trial Matters Statistically
Statistically, this study is notable for its repeated, within-participant structure and its use of a count based on biological samples. Both features require attention to what constitutes an observation. The number of negative samples depends on the number submitted, while repeated observations from one participant are related rather than independent. These are central considerations when interpreting a phase comparison.
The A-B-A sequence also illustrates the distinction between observing a pattern and identifying a causal effect. Having baseline observations before and after the B phase can describe the sequence of measurements, but the phases are not randomized groups. Since the same participants proceed through the phases in order, time and phase are linked. The registry does not report an analysis plan that addresses this issue.
The study description also connects the proposed contingency-management system with smartphone input, ecological momentary assessments, geospatial mapping, and portable biomarker feedback. The registry lists app usage feasibility and treatment retention as secondary outcomes, signaling that implementation-related questions were part of the stated study scope. Numerical results for those outcomes are not reported in the registry record.
Finally, the record underscores why outcome definitions, denominators, analysis populations, and uncertainty estimates matter. A count of negative tests is not self-interpreting when participants may submit different numbers of tests. Without phase-specific results and documented analysis methods, readers can identify the intended measurement and design but cannot assess the size or precision of an observed change. This distinction is important when early-stage or feasibility-oriented research is discussed: a study’s question and structure are informative, but they are not substitutes for reported outcome results.
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 primary limitation for interpreting results is that the registry does not report numerical primary outcome findings. It describes the number of negative BAC samples by phase but gives no phase-specific counts, denominators, effect estimate, or measure of uncertainty. The record also lists zero analysis entries. As a result, the primary research question cannot be answered from the recorded outcome information.
The design is a single-group A-B-A sequence, not a randomized comparison between separate intervention and control groups. All participants were to experience the phases in the same stated order. This makes phase and time difficult to distinguish, and the registry does not report methods for addressing possible time trends or carryover. The record also does not report whether all participants completed all phases.
The endpoint depends on submitted breath samples, and the registry notes that analyzed numbers vary with the total submitted by each participant. Phase-specific submission totals, reasons for missing samples, and missing-data procedures are not reported. Without this information, raw counts could be difficult to compare across participants or phases.
Further details needed to assess the analysis are not reported in the registry record, including the statistical model, handling of within-participant dependence, analysis populations, confidence intervals, hypothesis tests, and multiplicity procedures. The registry also does not report the numerical results for app usage feasibility or treatment retention. The adverse-event record provides phase counts but does not report event descriptions or whether the same individuals appear in more than one phase.
These limitations concern what can be concluded from the registry record; they do not establish that unreported procedures or results do not exist elsewhere.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Automated Reinforcement Management System (ARMS) — NCT04656925.
- Registry record last updated 2026-05-14; status last verified 2026-05.
- Results first posted 2025-02-05.
- 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
ARMS (NCT04656925) is a completed study sponsored by Washington State University. The registry lists 12 enrolled participants and a single-group, unmasked design, with allocation listed as NA. The official title calls it a Phase I study, while the phase field is listed as NA.
Participants were assigned to an A-B-A sequence: two weeks in the first A phase, four weeks in the B phase, and two weeks in the second A phase. The primary outcome was the number of negative BAC samples by phase, using breath samples submitted three times daily. Secondary outcomes were feasibility of app usage and treatment retention.
The registry does not report numerical primary or secondary outcome results, analysis entries, or a statistical analysis plan. It records zero serious adverse events and zero deaths in each phase, with other adverse events listed for the first A and B phases.