Adaptive Disclosure: A Combat-Specific PTSD Treatment: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Adaptive Disclosure: A Combat-Specific PTSD Treatment (NCT01628718), a randomized na study. The primary outcome is Clinical Status of Participants as Measured by the Clinician-Administered PTSD Scale for DSM-IV (CAPS-IV).

2. Clinical Question

The trial was randomized and used a parallel-group design. It was described as a non-inferiority trial, which means its objective was to assess whether the new treatment’s outcomes were not unacceptably worse than those under the comparator, according to a prespecified criterion. That criterion and the numerical results needed to evaluate it are not reported in the registry record. The study also described depression and functioning as part of its broader objective, but the record identifies the CAPS-IV clinical-status measure as the primary outcome.

3. Trial Design

The registry identifies NCT01628718 as a randomized, single-masked, parallel-group trial of Adaptive Disclosure (AD) and Cognitive Processing Therapy, cognitive version only (CPT-C). Both interventions are behavioral. Enrollment is listed as 122. The study status is completed; the recorded start is 2013-03 and primary completion is 2019-01. Phase is listed as NA. The sponsor is the Veterans Medical Research Foundation.

Participants were assigned to one of the two treatment approaches. The record does not say who was masked, how randomization was generated or concealed, or whether treatment providers or outcome assessors knew treatment assignments. Those details are important for understanding potential sources of bias, but they are not reported in the registry record.

The treatment schedules differed: AD consisted of eight 90-minute one-on-one sessions, while CPT-C consisted of 12 60-minute one-on-one sessions. Thus, the comparison was between treatment packages with different session schedules, not simply between two names for an otherwise identical intervention. The registry does not report adherence, treatment fidelity, concurrent care, or whether participants completed their assigned sessions.

The stated objective was non-inferiority: assessing whether AD was at least as effective as CPT-C for deployment-related psychological health problems, specifically PTSD and depression, and functioning. The record does not report the non-inferiority margin, the rationale for its choice, or the statistical decision rule. Without those details, and without the primary-outcome results, the trial’s non-inferiority conclusion cannot be reconstructed from the registry entry.

The primary outcome was clinical status measured by the Clinician-Administered PTSD Scale for DSM-IV (CAPS-IV), assessed from pre-treatment baseline to post-treatment at 8-12 weeks. Its stated analysis population was intent to treat. The record lists one outcome measure and one analysis, but it does not provide the outcome values or analysis methods needed to interpret that analysis.

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

Analysis population for the primary outcome, as defined in the registry: Intent to treat

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Clinical Status of Participants as Measured by the Clinician-Administered PTSD Scale for DSM-IV (CAPS-IV), measured over Pre-treatment (baseline), post-treatment (8-12 weeks).

The primary endpoint is clinical status based on change in CAPS-IV from pre-treatment baseline to post-treatment at 8-12 weeks. The registry describes participants as classified according to whether they recovered, improved, remained unchanged, or deteriorated. Recovery requires meeting the Reliable Change Index (RCI) threshold and having change of at least 2SD from baseline to post-treatment. Improvement is defined by meeting the positive RCI threshold. Unchanged status means not meeting an RCI threshold, while deterioration means meeting the negative RCI threshold.

These categories aim to describe the direction and meaningfulness of change at the participant level, rather than reporting only an average score. In general, an RCI is used to distinguish change that is larger than expected measurement variation from change that may reflect such variation. The registry does not give the numerical thresholds, the calculation details, or the category counts for either treatment group.

The endpoint is clinically interpretable in concept because it groups change into improvement-oriented and deterioration-oriented statuses. However, interpretation requires the observed distribution across categories and a clear comparative analysis. Neither is reported in the registry record. The endpoint description therefore explains what was intended to be measured, but it does not reveal how participants’ clinical status changed or how the groups compared.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation begins by distinguishing the study question from the results. The trial’s stated question was whether AD was at least as effective as CPT-C for deployment-related psychological health problems and functioning. That is a non-inferiority question. The registry provides the objective and the primary endpoint description, but it does not report the primary outcome data or the analysis estimates. A design label does not itself demonstrate that a non-inferiority criterion was met.

What does non-inferiority require?

In general, a non-inferiority study sets a margin representing the largest loss of effect that would still be considered acceptable for the new intervention. The treatment comparison is then evaluated relative to that margin, taking account of uncertainty. The margin, its clinical justification, and the statistical decision rule are not reported in the registry record. Without them, the intended criterion cannot be checked. A finding of no statistically significant difference would not, by itself, establish non-inferiority; the relevant question is whether the uncertainty around the treatment contrast excludes an unacceptable loss.

The record does not report a confidence interval or other uncertainty measure for the primary comparison. In general, an interval estimate communicates a range of effects compatible with the data under the analysis assumptions. Its width indicates precision, while its location relative to the non-inferiority margin informs the decision. Because neither an estimate nor an interval is reported, the precision and direction of the primary comparison are unknown from this entry.

How should the primary endpoint be read?

The endpoint groups CAPS-IV change into recovered, improved, unchanged, and deteriorated clinical statuses. The registry states that recovery requires meeting the RCI threshold and having change of at least 2SD from baseline to post-treatment. Improvement requires meeting the positive RCI threshold; unchanged status means not meeting an RCI threshold; deterioration requires meeting the negative RCI threshold. In general, an RCI is intended to help distinguish change that exceeds measurement variation from change that might arise from measurement error. The record does not provide the actual thresholds, the method for calculating them, or the numbers assigned to each status.

For a categorical endpoint, interpretation depends on the distribution of participants across the categories and on the planned comparison. Different summaries may emphasize different aspects of the data, such as favorable change or deterioration. The record does not state which contrast was used or how category counts entered the analysis. It also does not report the observed counts. The endpoint definition alone therefore cannot indicate whether clinical status favored either treatment.

What does randomization contribute?

In general, random assignment is intended to make treatment groups comparable at the start of a trial with respect to both measured and unmeasured characteristics, on average. That supports a causal comparison when allocation, follow-up, outcome measurement, and analysis are adequately conducted. The registry identifies the study as randomized, but does not report the sequence-generation method, allocation concealment, baseline characteristics, or implementation details. It also does not identify who was masked. The single-masked designation therefore cannot be translated into a specific account of which trial personnel or participants were unaware of assignment.

The parallel-group design assigns participants to a treatment group and compares outcomes across groups. The groups received different session schedules: AD was delivered in eight 90-minute one-on-one sessions and CPT-C in 12 60-minute one-on-one sessions. This is relevant when considering the interventions as complete treatment strategies. The record does not report treatment adherence, protocol deviations, or fidelity, so it cannot show how closely treatment delivery matched the stated schedules.

What do the planning assumptions mean?

The sample-size material is described as a planning illustration computed from the observed effect, rather than as the trial’s own design. Its stated assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. For non-time-to-event outcomes, the illustration is expressed as participants per arm for a specified power level; time-to-event illustrations use a total event count. These are planning scenarios, not observed power and not evidence that the trial was designed or adequately powered according to those assumptions.

Observed-effect planning illustrations should be treated cautiously in general. An effect estimated from a completed study may be uncertain, and planning estimates based on it inherit that uncertainty. A fraction of an observed effect is a scenario for planning, not a new observed treatment effect. The registry does not report the trial’s original sample-size justification, so the relationship between the planning illustration and the original design cannot be established.

For binary or categorical outcomes, general methods may rely on assumptions about the distribution of counts and the model used for comparison. If outcomes are clustered or more variable than a model assumes, over-dispersion can make standard errors too small and intervals too narrow unless the analysis accounts for that variation. The registry does not report a model, an over-dispersion assessment, or other modeling details for the CAPS-IV status outcome. This general issue should not be read as evidence that over-dispersion occurred in this trial.

The record lists one outcome measure and one analysis, while the primary outcome itself has multiple clinical-status categories. The endpoint description and the analysis count do not reveal whether there were additional comparisons, how the categories were handled, or whether any analysis was adjusted. The analysis plan and its prespecification are not reported in the registry record. Consequently, neither the handling of multiplicity nor the robustness of the primary analysis can be evaluated from the available information.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists one outcome measure and one analysis. The primary outcome, however, is described through several status categories: recovered, improved, unchanged, and deteriorated. The record does not say which category comparison or summary measure was analyzed, whether the categories were combined for analysis, or whether additional contrasts were performed. It also does not report a statistical analysis plan or describe any adjustment for multiple testing. Therefore, the number of outcome measures and analyses listed cannot by itself establish how multiplicity was handled.

In general, multiplicity arises when multiple outcomes, time points, groups, or contrasts are assessed. Repeated testing can increase the chance of a seemingly notable finding arising by chance unless the analysis plan addresses it. This is a general consideration, not a claim that multiplicity affected this trial. The record identifies the CAPS-IV assessment from baseline to post-treatment at 8-12 weeks, but does not report whether other outcomes or time points contributed to inferential testing.

The primary outcome population is described as intent to treat. The registry does not report missing-data counts, reasons for missing assessments, participant flow, imputation methods, or sensitivity analyses. In general, missing outcomes can complicate comparisons if missingness is related to treatment assignment or participants’ outcomes. Without details on the extent and handling of missing data, the impact on the result cannot be judged.

The registry also does not report whether the analysis included every randomized participant as intended by the stated population, how deviations were handled, or whether a per-protocol analysis was performed. Those details can matter in non-inferiority studies, where different analysis populations may be informative in different ways. No conclusion about analysis-population robustness can be drawn from the intent-to-treat label alone.

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: alcohol poisoning (1.7%), dissociative episode (1.6%), suicide attempt (1.6%).

The adverse-event record reports serious adverse events separately from other adverse events. In CPT-C, 1 serious adverse event affected among 60 at risk, and 4 other adverse events were recorded among 60 at risk. In AD, 2 serious adverse events affected among 62 at risk, and 10 other adverse events were recorded among 62 at risk. Deaths are recorded as 0 in each group.

These are descriptive counts, not a statistical comparison. The record does not report event timing, whether events occurred in the same participant, the nature of each event by treatment group, duration of follow-up for safety, or whether investigators considered events related to treatment. It also does not provide a comparative effect estimate or uncertainty interval. The counts therefore should not be interpreted as establishing that one intervention is safer than the other.

The registry separately lists Alcohol poisoning at 1.7%, Dissociative episode at 1.6%, and Suicide attempt at 1.6% among the top serious terms. The record does not clarify the denominator, group assignment, or other context for those percentages. They should not be combined with the group-level counts or treated as a treatment-specific comparison without that information.

In general, adverse-event counts describe events recorded under the study’s reporting procedures. Their interpretation depends on definitions, ascertainment, exposure, and follow-up. Those details are not reported in the registry record, so the figures provide a limited descriptive safety account.

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

The registry record establishes that a randomized, parallel-group trial compared AD with CPT-C and that the intended primary outcome was CAPS-IV clinical status from baseline to post-treatment at 8-12 weeks. It also describes the treatment schedules and records some adverse-event counts. These details clarify what the trial set out to study and what was recorded for safety.

The record does not include the primary outcome category counts, a treatment comparison, an effect estimate, or a measure of uncertainty. It therefore cannot show whether clinical status was more favorable in either group, whether the difference was small or large, or how precise the comparison was. It also cannot establish whether AD met the stated non-inferiority objective. That conclusion would require the observed comparative results and the non-inferiority margin and analysis criteria, which are not reported in the registry record.

The endpoint definitions describe how recovery, improvement, unchanged status, and deterioration were classified, but definitions are not results. Likewise, a completed study status does not reveal the outcome. The stated intent-to-treat population does not show how many assessments were available or how missing data were handled.

The safety counts document recorded serious and other adverse events, along with zero recorded deaths in each group. They do not by themselves provide a comparative safety conclusion. The event terms and percentages listed separately lack the context needed to assign them to a treatment group or interpret their denominator.

In general, a trial report is most informative when it presents the prespecified outcome, the actual group results, an effect estimate with uncertainty, and enough methods detail to understand the analysis. The registry entry supplies the trial objective and endpoint description but not those comparative efficacy results. Its findings should therefore be treated as unavailable for clinical-effect interpretation rather than as evidence for or against either treatment.

13. Why This Trial Matters Statistically

This trial is statistically notable for posing a non-inferiority question rather than simply asking whether two treatments differ. Non-inferiority requires a prespecified acceptable margin and an analysis that evaluates the treatment contrast against that margin while accounting for uncertainty. The registry identifies the intended framework, but does not report the margin, its rationale, or the primary comparative results. This illustrates why a study’s label and objective are not enough to assess its statistical conclusion.

The primary endpoint is also more interpretive than a simple average score: it classifies CAPS-IV change as recovered, improved, unchanged, or deteriorated using RCI-based criteria. Such categories can communicate clinically oriented change, but their usefulness for comparison depends on transparent thresholds, category counts, and a defined analysis. The registry describes the classifications without providing these results.

The trial compares two behavioral treatment packages with different session schedules. The design therefore concerns the complete interventions as delivered, while the registry does not report adherence or fidelity. For statistical interpretation, implementation and outcome availability can affect how well a randomized comparison reflects the intended treatment strategies.

Finally, this record distinguishes the existence of a completed trial from the availability of interpretable outcome results. It gives a clear research question, endpoint, and selected safety counts, yet omits the primary effect estimate and its precision. That gap is important: a reader cannot infer non-inferiority, equivalence, or superiority from the design alone. The case underscores the need for complete reporting of margins, analysis methods, group outcomes, and missing-data handling when interpreting a non-inferiority trial.

14. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The main limitation for interpreting this trial from the registry record is that primary outcome results are not reported. The record describes the CAPS-IV clinical-status endpoint and its categories, but provides no category counts, group comparison, effect estimate, or uncertainty measure. The treatment question therefore cannot be answered from the listed information.

The non-inferiority framework is also incompletely described. The margin, its justification, and the decision rule are not reported in the registry record. These are central to interpreting a non-inferiority study, so the stated objective cannot be independently evaluated.

Important design and analysis details are absent. The record does not report the randomization procedure, allocation concealment, the identity of the masked party, baseline group characteristics, the statistical model, or whether the analysis plan was prespecified. The phrase single-masked does not identify whose knowledge of treatment assignment was restricted.

The registry does not describe participant flow, missing assessments, reasons for missingness, imputation, sensitivity analyses, treatment adherence, or protocol deviations. Although the primary outcome population is labeled intent to treat, the operational details of that analysis are unavailable. These omissions limit assessment of bias and robustness.

Safety information is also limited. Group-level counts are given, but event timing, attribution, duration of follow-up, and details linking the listed serious-event terms to groups are not reported. The separate percentages have no stated denominator or group context. The record consequently supports only a narrow descriptive reading of safety, not a comparative conclusion.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Adaptive Disclosure: A Combat-Specific PTSD Treatment — NCT01628718.
• Registry record last updated 2020-04-09; status last verified 2020-03.
• Results first posted 2020-04-09.
• 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

NCT01628718 is a completed randomized, single-masked, parallel-group trial sponsored by the Veterans Medical Research Foundation. It compared Adaptive Disclosure with cognitive-only Cognitive Processing Therapy for PTSD. Enrollment is listed as 122; the recorded start is 2013-03 and primary completion is 2019-01. Phase is listed as NA.

The stated objective was to assess whether AD was at least as effective as CPT-C for deployment-related psychological health problems, specifically PTSD and depression, and functioning. The primary endpoint was CAPS-IV clinical status from baseline to post-treatment at 8-12 weeks, with an intent-to-treat population. AD was delivered in eight 90-minute one-on-one sessions; CPT-C in 12 60-minute one-on-one sessions.

The registry describes the endpoint categories and reports group-level adverse-event counts, but does not report primary outcome results, the non-inferiority margin, or the comparative analysis needed to interpret efficacy. The record therefore does not establish whether the non-inferiority objective was met.