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 Enhancing Adolescent Substance Abuse Treatment (NCT03249350), a randomized na study. The primary outcome is Changes From Baseline Scores Compared to Post-Treatment Scores, Any Positive Youth Urine Drug/Alcohol Screens (Measured at 0, 2, 4, 6, 9, & 12 Months)..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03249350 |
| Phase | NA |
| Condition | Substance Use Disorders |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 129 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Oregon Social Learning Center |
| Results posted | Yes |
2. Clinical Question
Population
Adolescents receiving treatment for substance abuse are the population of interest. The registry record identifies substance use disorders as the condition and records enrollment of 129 participants. It does not report further eligibility details or a fuller description of the analyzed population.
Intervention
Enhanced Contingency Management (CM+), described as an enhanced protocol for adolescent substance abuse that targets parenting more intensely.
Comparator
Standard Contingency Management (CM), described as standard CM for adolescent substance abuse.
Primary question
How did the mean number of positive urine drug or alcohol screens change from baseline through 12 months in the two treatment groups? The registry lists measurements at 0, 2, 4, 6, 9, and 12 months. It does not report the group-specific means, the estimated between-group contrast, or its uncertainty, so the comparative result cannot be determined from the registry record.
The trial’s stated research goal was to evaluate factors that may contribute to change during adolescent substance abuse treatment, with the broader aim of identifying mechanisms that could be targeted more intensively. The enhanced arm specifically emphasizes parenting. The primary endpoint, however, is a measure of positive urine drug or alcohol screens rather than a direct measure of parenting or of a mediation mechanism. The listed secondary outcomes include youth problem behaviors, receipt of required CM components, and parent-management measures reported by parents or youth. Results for those outcomes are not reported in the registry record.
3. Trial Design
The registry describes a randomized, parallel-group trial with single masking. It records the study as completed, with enrollment of 129. The recorded phase is NA. The study start date is 2018-04-23, and the primary completion date is 2024-03-29. The sponsor is Oregon Social Learning Center.
Participants were assigned to one of two behavioral interventions: Standard Contingency Management (CM) or Enhanced Contingency Management (CM+). The standard arm is described as receiving standard CM for adolescent substance abuse. The enhanced arm is described as receiving an enhanced CM protocol that targets parenting more intensely. The registry does not describe the masking procedure, who was masked, how the randomization sequence was generated, or whether allocation was concealed; these details are not reported in the registry record.
The primary outcome is described as changes from baseline scores compared with post-treatment scores for any positive youth urine drug or alcohol screens. Measurements are listed at 0, 2, 4, 6, 9, and 12 months, and the timeframe is baseline to 12 months. The registry identifies the outcome as a mean of a continuous measure, with standard error as its dispersion measure. It does not specify in the posted record how repeated measurements were combined or modeled, what estimate served as the principal treatment comparison, or how the analysis handled participants with incomplete follow-up.
The registry lists 24 outcome measures and 25 analyses. Those counts alone do not identify which analyses were confirmatory, how outcomes were prioritized, or whether multiplicity adjustments were planned. Such details are not reported in the registry record. The broad research objective concerns mechanisms of change, but a specific mediation analysis plan and its results are not reported.
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: Study participants include adolescents aged 12-18 years with substance use disorders. All 129 adolescents enrolled in the study met the inclusion criteria and were randomized to treatment. Only adolescents were considered enrolled in the study.
Overall Study
| Stage | Standard Contingency Management (CM) | Enhanced Contingency Management (CM+) |
|---|---|---|
| STARTED | 66 | 63 |
| COMPLETED | 61 | 55 |
| NOT COMPLETED | 5 | 8 |
Reasons for not completing this period:
| Reason | Standard Contingency Management (CM) | Enhanced Contingency Management (CM+) |
|---|---|---|
| Participant did not initiate treatment | 5 | 8 |
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 | Standard Contingency Management (CM) | Enhanced Contingency Management (CM+) | Total |
|---|---|---|---|---|
| Participants analysed | 66 | 63 | 129 | |
| Age, Continuous | years | 14.76 (SD 1.49) | 14.98 (SD 1.36) | 14.87 (SD 1.43) |
| Sex: Female, Male: Female | Participants | 24 | 26 | 50 |
| Sex: Female, Male: Male | Participants | 42 | 37 | 79 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 8 | 16 | 24 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 57 | 47 | 104 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 1 | 0 | 1 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 3 | 2 | 5 |
| Race (NIH/OMB): Asian | Participants | 1 | 0 | 1 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 2 | 2 | 4 |
| Race (NIH/OMB): Black or African American | Participants | 1 | 2 | 3 |
| Race (NIH/OMB): White | Participants | 58 | 52 | 110 |
| Race (NIH/OMB): More than one race | Participants | 1 | 4 | 5 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 1 | 1 |
| Region of Enrollment: United States | participants | 66 | 63 | 129 |
| Total Positive Urine Drug Screen | count of positive screens | 0.82 (SD 0.72) | 0.84 (SD 0.65) | 0.83 (SD 0.69) |
| Any Positive Urine Drug Screen | proportion of participants | 0.68 | 0.73 | 0.71 |
| Global Appraisal of Individual Needs (GAIN) Substance Problem | units on a scale | 6.73 (SD 4.33) | 7.19 (SD 4.73) | 6.95 (SD 4.52) |
| Global Appraisal of Individual Needs (GAIN) Substance Dependence | units on a scale | 3.15 (SD 2.33) | 3.27 (SD 2.49) | 3.21 (SD 2.4) |
| Global Appraisal of Individual Needs (GAIN) Substance Frequency | units on a scale | 22.89 (SD 17.37) | 21.9 (SD 17.42) | 22.4 (SD 17.3) |
| Child Behavior Checklist (CBCL) - Externalizing Youth Report | units on a scale | 22.88 (SD 10.19) | 24.6 (SD 11.09) | 23.72 (SD 10.63) |
| Child Behavior Checklist (CBCL) - Externalizing Parent Report | units on a scale | 31.95 (SD 15.18) | 28.03 (SD 13.91) | 30.04 (SD 14.65) |
| Peer Delinquency | units on a scale | 15.42 (SD 13.75) | 14.83 (SD 10.74) | 15.13 (SD 12.33) |
| Positive Peer Activity - Youth Report | units on a scale | 16.62 (SD 5.92) | 15.16 (SD 5.94) | 15.91 (SD 12.33) |
6. Primary Endpoint
The registry lists the primary outcome as Changes From Baseline Scores Compared to Post-Treatment Scores, Any Positive Youth Urine Drug/Alcohol Screens (Measured at 0, 2, 4, 6, 9, & 12 Months)., measured over Baseline to 12 months.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Error |
| Unit | positive test per timepoint |
| Endpoint classification | Continuous Endpoint |
The primary endpoint concerns any positive youth urine drug or alcohol screen. The registry description includes screens for tetrahydrocannabinol (THC), synthetic THC, amphetamines, opiates, phencyclidine (PCP), cocaine, and alcohol metabolites (ethyl glucuronide and ethyl sulfate). Its stated unit is positive test per timepoint, and the recorded summary measure is a mean. Measurements are scheduled at baseline and at 2, 4, 6, 9, and 12 months, covering the baseline-to-12-month timeframe.
A repeated screening measure can describe the pattern of detected substance use over follow-up, rather than relying on a single assessment. A positive result represents detection at a particular measurement time; the registry description does not say that the endpoint is a count of unique participants, a count of all positive tests across the whole study, or a measure of substance use outside the screening periods. It also does not report how missing or unavailable samples were treated.
The endpoint is relevant to the stated treatment research because it measures urine-screen findings during follow-up. The registry does not state the exact clinical interpretation assigned to a change in this measure. Nor does it post the group means or a comparative estimate. Consequently, the endpoint’s definition is available, but the degree or direction of any observed difference between CM and CM+ is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record defines a repeated primary outcome and identifies the two treatment arms, but it does not post numerical primary-outcome results. There are no group-specific means, standard errors, changes from baseline, between-arm estimates, confidence intervals, or p-values in the recorded details. The direction, magnitude, and precision of the primary comparison therefore cannot be assessed from the registry record.
This absence is especially important because the primary outcome covers several time points. The record does not reduce those measurements to one comparison, and there is no single reported contrast to interpret. A reader cannot tell from the listed endpoint definition whether groups differed at any particular assessment, whether a difference persisted across follow-up, or whether an overall repeated-measures estimate was calculated. Those results are not reported in the registry record.
In general, a mean describes the average value of a measure in a group, while a standard error describes the estimated precision of that mean. Neither is a substitute for a direct comparison between treatment groups. A confidence interval, if reported, would describe a range of values compatible with the estimated contrast under the analysis assumptions. The registry record does not report a confidence interval for the primary comparison, so its precision cannot be characterized.
The study enrolled 129 participants, but enrollment alone does not establish how many contributed data at each time point or to each analysis. The record does not report outcome-specific analyzed sample sizes, attrition by arm, or the treatment of missing observations. These omissions limit assessment of how representative the analyzed observations may be of the randomized groups.
The registry lists secondary outcomes concerning youth problem behaviors, receipt of required CM components, and parent-management measures from parent and youth reports. It also lists counts of outcomes and analyses. However, no comparative estimates for those secondary outcomes are reported in the registry record. The trial’s stated aim of examining mechanisms of change should not be mistaken for evidence that a particular mechanism was demonstrated: the registry entry does not report mediation estimates or their uncertainty.
The posted safety information provides event counts, but it does not supply the missing efficacy estimates. Safety counts and the primary urine-screen endpoint answer different questions and should be interpreted separately. Overall, the record describes the design and the measures but does not provide enough outcome statistics to quantify a treatment contrast or determine how precisely it was estimated.
9. Statistical Methods Explained
The registry identifies the primary measure as a mean of a continuous outcome, with standard error as the dispersion measure. It does not report a treatment-effect estimate or a detailed analysis plan. The concepts below are general explanations of how such measures and analyses are commonly interpreted; they are not claims about methods used in this trial unless the registry explicitly records them.
What a mean and standard error describe
General: a mean summarizes the average observed value in a group. For this trial, the stated unit is positive test per timepoint. A standard error describes uncertainty in an estimated mean, rather than the spread of individual participants’ values. A standard deviation, by contrast, describes variability among observations. The registry lists standard error as the dispersion measure but does not post the actual means or standard errors for the primary outcome.
General: an estimated treatment contrast compares outcomes between groups according to a defined analysis. The contrast might focus on a particular time point, change from baseline, or a pattern across repeated measurements. These choices answer different questions. The registry identifies assessments at 0, 2, 4, 6, 9, and 12 months, but does not report which specific contrast was used as the principal comparison or how those repeated observations were modeled.
Why repeated observations need an analysis plan
General: observations from the same participant over time are often correlated; they are not necessarily independent pieces of information. Methods for repeated measurements account for that within-participant relationship and can use information from multiple assessment times. The choice of method can affect the estimated contrast and its uncertainty. The registry does not identify a repeated-measures model, its assumptions, or any adjustment variables.
General: a confidence interval expresses the uncertainty around an estimate in a way that is often more informative than a significance test alone. Its interpretation depends on the analysis assumptions and the data used. A p-value addresses compatibility with a specified null hypothesis under a statistical model; it does not measure the size or practical importance of an effect. No primary-outcome confidence interval or p-value is reported in the registry record, so neither the precision nor the statistical evidence for a group contrast can be evaluated.
What the sample-size assumptions mean
The registry’s planning description specifies a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. It says the planning effect is a stated fraction of the observed effect. These are planning assumptions, not observed trial results. The registry does not report the effect estimate used for this planning illustration or the resulting participant counts, so no specific planning count can be interpreted from the record.
General: sample-size calculations describe how many participants an assumed design may require to detect an assumed effect under stated conditions. Such calculations do not establish the probability that the completed trial found an effect, and they are not observed power. In particular, a calculation based on an observed effect is conditional on that effect estimate and is not a substitute for the confidence interval around the actual treatment comparison. Any sample-size illustration should be distinguished from the number enrolled and from the number analyzed.
Why variability and distribution matter
General: a normal approximation may be used for some planning calculations or statistical models, but its adequacy depends on the outcome distribution and design. Measures based on counts or events can be skewed or show more variability than a simple model expects. Over-dispersion means that observed variability exceeds what a model assumes; if ignored, uncertainty may be understated. These are general considerations, not evidence that over-dispersion occurred in this trial. The registry does not report distributional checks or model diagnostics.
The primary endpoint is described as a mean of a continuous measure, although its unit refers to positive tests at each time point. The record does not explain the construction of the measure sufficiently to determine its distribution or whether a count-based model was considered. It also does not report whether observations were weighted, transformed, or adjusted. Those analysis details are not reported in the registry record.
What can be concluded from the statistical record
The design and outcome schedule are recorded, as are enrollment and broad analysis counts. The principal statistical quantities needed to interpret the primary comparison are not: no arm-specific outcome summaries, treatment contrast, confidence interval, or p-value are posted. As a result, statistical concepts can clarify what those quantities would mean, but cannot fill in the missing estimate or establish the direction, magnitude, or precision of a result.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 24 outcome measures and 25 analyses, including multiple outcomes and repeated assessments. Considering many outcomes or time points can raise multiplicity concerns: when numerous statistical comparisons are made, the chance of finding at least one apparently notable result may differ from that for a single prespecified test. General statistical approaches can address this issue by defining a primary comparison in advance or adjusting inference across a family of tests. The registry record does not report whether such an approach was planned or used.
The primary outcome itself is measured at several time points. The record does not specify whether a single time point, an overall trajectory, or another summary was designated as the main inferential target. It also does not report a hierarchy for secondary outcomes or distinguish confirmatory from exploratory analyses. Consequently, the intended multiplicity framework cannot be reconstructed from the posted record.
Missing data are also relevant to repeated follow-up. The registry does not report the number of participants with available measurements at each assessment, reasons for missingness, or the method used to handle incomplete observations. It does not state whether the primary analysis followed an intention-to-treat principle, included only participants with observed outcomes, or used another analysis population. These details are not reported in the registry record.
Without outcome-specific denominators and analysis-population definitions, enrollment cannot be treated as the sample size for every analysis. The record’s counts of outcomes and analyses do not resolve how missing observations or multiple comparisons were handled. These limitations concern interpretation of the statistical evidence, not proof that the analysis was or was not appropriate.
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 |
|---|---|---|---|
| Standard Contingency Management (CM) | 7 | 66 | 10.6% |
| Enhanced Contingency Management (CM+) | 7 | 63 | 11.1% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Standard Contingency Management (CM) | 3 of 66 |
| Enhanced Contingency Management (CM+) | 0 of 63 |
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 |
|---|---|
| Standard Contingency Management (CM) | 7 of 66 |
| Enhanced Contingency Management (CM+) | 5 of 63 |
Most frequent serious adverse event terms
| Event term | Organ system | Standard Contingency Management (CM) | Enhanced Contingency Management (CM+) |
|---|---|---|---|
| Non-fatal Substance Use Overdose | Injury, poisoning and procedural complications | 5 of 66 | 2 of 63 |
| Suicide Attempt | Psychiatric disorders | 1 of 66 | 2 of 63 |
| Psychiatric Facility Admission | Psychiatric disorders | 1 of 66 | 1 of 63 |
| Behavioral Escalation | Psychiatric disorders | 0 of 66 | 1 of 63 |
| Physical Injury | Injury, poisoning and procedural complications | 0 of 66 | 1 of 63 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Standard Contingency Management (CM) | Enhanced Contingency Management (CM+) |
|---|---|---|---|
| Mandatory Child Abuse Report | Social circumstances | 6 of 66 | 5 of 63 |
| Mandatory Report to Law Enforcement | Social circumstances | 1 of 66 | 0 of 63 |
Serious events with the highest arm-level rate: non-fatal substance use overdose (7.6%), suicide attempt (3.2%), psychiatric facility admission (1.6%), behavioral escalation (1.6%), physical injury (1.6%).
The registry records serious adverse events for 66 participants at risk in the standard CM arm and 63 at risk in the enhanced CM+ arm. Serious adverse events affected 7 participants in each arm. Other adverse events affected 7 participants in the standard arm and 5 in the enhanced arm. The record lists 3 deaths in the standard arm and 0 in the enhanced arm.
These are counts, not estimates of a causal effect of either intervention. The registry record does not explain whether events were judged related to treatment, provide event timing, or give additional detail about the circumstances of the deaths. The listed at-risk counts and affected-participant counts do not indicate how events were distributed across time or whether an individual experienced more than one event.
The registry also lists the following top serious-event terms and percentages: Non-fatal Substance Use Overdose, 7.6%; Suicide Attempt, 3.2%; Psychiatric Facility Admission, 1.6%; Behavioral Escalation, 1.6%; and Physical Injury, 1.6%. The record does not provide an arm-specific breakdown for these terms or explain their denominators in the registry record recorded. These percentages should therefore be read as registry-listed figures, not as a basis for calculating comparative risk.
Safety counts should be considered separately from the primary urine-screen endpoint. The counts alone do not establish whether an intervention caused an event or whether groups differ in safety; the registry does not report a formal comparative safety analysis.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, parallel-group comparison was conducted between standard CM and an enhanced CM protocol targeting parenting more intensely. It also identifies a primary endpoint based on positive youth urine drug or alcohol screens, measured repeatedly from baseline through 12 months. These details clarify the question the trial was organized to address.
The record does not report the primary outcome estimates or the comparative results for the secondary outcomes. It therefore does not show whether average screening results differed between arms, by how much they differed, or how precisely any contrast was estimated. It also does not establish whether any treatment difference persisted across follow-up or whether a proposed mechanism of change was supported.
General: a trial design and an outcome definition describe how evidence could be generated, but they do not substitute for the observed results. A conclusion about the direction or magnitude of a treatment contrast requires an estimate; a conclusion about its precision requires uncertainty information such as a confidence interval or standard error for the contrast. Those comparative statistics are not reported in the registry record.
The enrollment figure is not a result and does not reveal the number of participants contributing data to each outcome analysis. Similarly, the listed safety events are descriptive counts and do not by themselves establish causation or comparative safety. The trial’s stated objective is to investigate mechanisms that may contribute to change in treatment, but the registry does not report mediation findings. The defensible interpretation is therefore limited to the trial’s design, outcome definitions, enrollment, and recorded event counts; the comparative treatment result remains unreported.
13. Why This Trial Matters Statistically
This trial is statistically notable for linking a treatment comparison with a stated interest in mechanisms of change. The two arms differ in whether the CM protocol targets parenting more intensely, while the primary outcome measures positive drug or alcohol screens over repeated assessments. The registry also lists parent-management measures, youth problem behaviors, and receipt of required CM components as secondary outcomes. Together, these measures indicate the kinds of processes and outcomes the study set out to examine.
Repeated assessment can be useful because a treatment contrast may vary over time. It also makes the analysis more complex: the statistical question must define how measurements within participants are related and which time-based comparison is primary. The registry lists multiple time points and many outcome measures, but does not report the analysis plan, multiplicity handling, or comparative estimates. This makes transparent reporting of estimands, analysis populations, missing-data methods, and uncertainty especially important for interpreting a study of this structure.
The registry’s planning assumptions also illustrate a general distinction between design calculations and trial findings. Planning assumptions concern a hypothetical effect and analysis framework; they do not show what the completed trial observed. Without the actual primary estimate and its uncertainty, the scientific contribution of the comparison cannot be assessed from the registry record alone.
More broadly, the record shows why outcome definitions and design information are necessary but not sufficient for statistical interpretation. Readers need the numerical results, analysis choices, and data completeness information to judge what the observed evidence supports. Those details are not reported in the registry 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 central limitation of the posted record is the absence of numerical results for the primary endpoint. Group means, standard errors, between-arm estimates, confidence intervals, and p-values are not reported. This prevents assessment of the direction, size, and precision of the primary comparison. Numerical comparative results for the listed secondary outcomes are also not reported.
The outcome schedule is specified, but the principal repeated-measures contrast and statistical model are not. The registry does not state whether the main comparison concerned a particular assessment, change from baseline, or the pattern across follow-up. Details of covariate adjustment, model assumptions, diagnostics, and handling of within-participant correlation are not reported in the registry record.
Information about analysis populations and data completeness is also absent. The record does not provide participant counts analyzed by arm and time point, reasons for missing measurements, or methods for handling missing data. It does not say whether analyses used an intention-to-treat population or another population. These omissions make it difficult to evaluate attrition and the relation between enrollment and outcome analyses.
The registry lists many outcomes and analyses but does not report which were prespecified as confirmatory, how multiplicity was addressed, or whether analyses changed from an original plan. It also does not report a detailed mediation analysis, despite the stated interest in mechanisms of change. Finally, masking is recorded as single, but who was masked and how masking was implemented are not described. These limitations reflect missing information in the registry record; they do not establish that these procedures were absent from the study itself.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Enhancing Adolescent Substance Abuse Treatment — NCT03249350.
- Registry record last updated 2025-11-14; status last verified 2025-10.
- Results first posted 2025-11-14.
- 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
NCT03249350, titled “Enhancing Adolescent Substance Abuse Treatment,” is recorded as a completed, randomized, single-masked, parallel-group behavioral trial sponsored by Oregon Social Learning Center. Enrollment was 129. The recorded study start date is 2018-04-23, and the primary completion date is 2024-03-29.
The trial compared Standard Contingency Management (CM) with Enhanced Contingency Management (CM+), described as targeting parenting more intensely. The primary outcome concerns mean positive youth urine drug or alcohol screens from baseline through 12 months, with assessments listed at 0, 2, 4, 6, 9, and 12 months. The registry lists 24 outcome measures and 25 analyses.
Primary and secondary comparative outcome results, detailed analysis methods, and missing-data handling are not reported in the registry record. Safety counts are posted for both arms, along with selected serious-event terms and percentages, but the record does not provide a comparative safety analysis or causal attribution.