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 Suppression of HIV 1 RNA in People Living With HIV (NCT02363387), a randomized na study. The primary outcome is Undetectable Viral Loads During Treatment.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02363387 |
| Phase | NA |
| Condition | HIV |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 102 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Johns Hopkins University |
| Results posted | Yes |
2. Clinical Question
Population
The trial concerned people living with HIV who received care in medical clinics. The registry record identifies the primary analysis population as intent to treat. The record reports enrollment of 102 participants, while the study summary describes a proposed group of N = 200 participants from clinics serving adults living with HIV in Baltimore. It does not give further eligibility criteria or participant characteristics.
Intervention
The intervention was incentives for viral suppression, added to standard HIV medical care offered in the participant’s clinic. The summary describes incentives for maintaining suppressed and undetectable viral loads, with incentives also for decreases in viral load before it reached undetectable levels. It describes frequent incentives early in treatment, reduced frequency as suppression continued, escalating incentives for sustained suppression, and an intervention maintained for two years.
Comparator
The comparator was usual care: standard HIV medical care offered in the clinic. The summary does not describe additional incentives for this group. The registry lists the intervention and comparator as behavioral interventions and identifies the study as randomized, parallel-group, and without masking.
Primary question
The primary question was whether the percentage of blood samples with undetectable viral loads differed between the groups during the two-year intervention period. Undetectable was defined as less than 200 copies/mL. Samples were assessed at eight three-month assessments, with a yes-or-no classification at each assessment. The reported comparison gives an odds ratio of 7.1, with a 95% confidence interval from 2.7 to 18.8 and p < 0.001. That result describes the posted analysis; it does not by itself establish why the groups differed or how broadly the result applies.
3. Trial Design
The registry describes a randomized, parallel-group trial with no masking. The study compared an incentive group with a usual-care group. The incentive group received standard clinic-based HIV medical care plus incentives linked to viral suppression; the usual-care group received standard HIV medical care. The registry lists Johns Hopkins University as the sponsor and the trial status as completed. The recorded start is 2015-11 and primary completion is 2019-10. The phase is listed as NA.
The study summary describes an intended two-year intervention, with assessments every three months during treatment and every six months during the year after treatment. Its stated primary outcome was the percentage of participants with undetectable viral loads at three-month assessments during the intervention. The primary outcome entry is more specifically described as the percentage of blood samples with undetectable viral loads across eight assessments during two years. The record therefore presents both participant-level wording in the summary and sample-level wording in the primary outcome description; it does not explain their relationship further.
The summary describes the incentive approach as including high-magnitude incentives, incentives for early decreases in viral load, more frequent incentives early in treatment, a lower frequency as suppression continued, and escalating incentives for sustained suppression. The intervention description in the arm record is truncated, so details beyond the complete study summary are not reported in the registry record. Five secondary outcomes are listed, covering medication adherence, prescriptions, retention in HIV medical care, and post-intervention effects.
There is a difference between the enrollment figure and the participant count stated in the summary: enrollment is 102, while the summary says N = 200. The registry record does not explain this difference. It also does not report further details about randomization procedures, allocation concealment, eligibility criteria, or participant characteristics.
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 | Incentive Group | Usual Care Group |
|---|---|---|
| STARTED | 52 | 50 |
| COMPLETED | 52 | 50 |
| NOT COMPLETED | 0 | 0 |
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.
| Characteristic | Unit | Incentive Group | Usual Care Group | Total |
|---|---|---|---|---|
| Participants analysed | 52 | 50 | 102 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 51 | 50 | 101 |
| Age, Categorical: >=65 years | Participants | 1 | 0 | 1 |
| Age, Continuous | years | 47 (SD 10) | 47 (SD 9) | 47 (SD 10) |
| Sex: Female, Male: Female | Participants | 24 | 23 | 47 |
| Sex: Female, Male: Male | Participants | 28 | 27 | 55 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 1 | 2 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 51 | 49 | 100 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 1 | 0 | 1 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 46 | 46 | 92 |
| Race (NIH/OMB): White | Participants | 4 | 4 | 8 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 1 | 0 | 1 |
| Region of Enrollment: United States | Participants | 52 | 50 | 102 |
6. Primary Endpoint
The registry lists the primary outcome as Undetectable Viral Loads During Treatment, measured over 2 years.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percentage of blood samples undetectable |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint concerns viral-load suppression measured through blood samples. A sample was classified as undetectable when the viral load was less than 200 copies/mL. The registry describes a yes-or-no determination at each of eight three-month assessments over the two-year intervention period, then defines the endpoint as the percentage of blood samples that were undetectable. The listed analysis population is intent to treat.
This type of endpoint captures repeated measurements during treatment rather than a single measurement at one time point. In general, repeated assessments can describe whether an outcome was observed across a period, but the exact interpretation depends on how observations are combined and how missing assessments are handled. Those details are not reported in the registry record. The summary’s participant-level wording—percentage of participants with undetectable viral loads—differs from the primary outcome entry’s sample-level wording. The record does not clarify whether the posted arm-level percentages refer to participants, samples, or a particular aggregation across assessments.
Viral-load measurement provides a defined laboratory outcome for the study’s stated question about suppression. The registry reports arm values of 70.4 for the incentive group and 42.5 for the usual-care group. The unit listed for the endpoint is percentage of blood samples undetectable. These values and the logistic-regression comparison should be read in the context of the endpoint definition and the unreported details of how repeated observations were analyzed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted arm-level values are 70.4 for the incentive group and 42.5 for the usual-care group. The registry reports a logistic-regression odds ratio of 7.1 for the comparison, with a 95% confidence interval from 2.7 to 18.8 and p < 0.001. The interval excludes 1, and the reported p-value is below 0.001. These are features of the reported statistical result; they do not resolve questions about endpoint construction, missing assessments, or analysis details that the registry does not describe.
An odds ratio compares the odds of an outcome between groups. It is not a ratio of percentages, and it should not be read as a direct statement that one group had a particular multiple of the other group’s probability. The registry identifies the analysis method as logistic regression and gives the comparison groups in the order Incentive Group and Usual Care Group. It does not report the model’s covariates, whether the analysis adjusted for repeated observations, or the exact unit used as an observation in that regression. Therefore, the numerical estimate can be quoted as the registry’s reported odds ratio, but additional modeling details cannot be inferred.
The 95% confidence interval runs from 2.7 to 18.8. In general, a confidence interval describes the statistical uncertainty around an estimate under the assumptions of the analysis. The broad span indicates that the point estimate is not highly precise on the odds-ratio scale, even though the interval remains above 1. The p-value is evidence against the statistical null hypothesis under the model used; it is not the probability that the null hypothesis is true, nor does it measure the size or practical importance of an effect.
The registry gives an intent-to-treat population for the primary endpoint, but does not explain how participants with incomplete assessments were handled. Because the endpoint refers to multiple assessments, that omission matters for interpreting what observations contributed to the estimate. The record also does not clarify the difference between the outcome’s participant-level wording in the summary and its sample-level definition in the primary outcome entry.
These results describe the posted comparison in this completed trial. They do not establish that the intervention caused the observed difference, settle the applicability of the result to other settings, or answer the listed secondary questions. Those conclusions require information beyond the reported arm values and model result.
9. Statistical Methods Explained
The registry reports logistic regression with an odds ratio as the effect measure. Logistic regression is a statistical method commonly used when the outcome is binary, such as a yes-or-no classification. In general, the method models the odds of the outcome in relation to group membership and any other variables included in the model. The registry does not report which other variables, if any, were included.
What the odds ratio expresses
Odds are different from probabilities: odds compare the chance of an event with the chance of its non-occurrence. An odds ratio compares those odds between groups. The reported estimate is 7.1 for the comparison of the incentive group with the usual-care group. It is not a percentage-point difference, and it does not mean that the probability of an undetectable result was 7.1 times as high. Converting an odds ratio into probabilities would require additional information and assumptions that are not reported in the registry record.
How to read the confidence interval and p-value
The reported 95% confidence interval extends from 2.7 to 18.8. In general, a confidence interval gives a range of estimates compatible with the data under the statistical model and its assumptions. A narrower interval indicates greater precision on the scale of the estimate; a wider interval indicates more uncertainty. The interval’s distance from 1 is relevant for an odds ratio because 1 represents equal odds between groups. The reported p-value is p < 0.001. In general, a p-value describes how unusual data at least as incompatible with the null hypothesis would be if that hypothesis and the model assumptions were true. It does not measure the probability that the result occurred by chance, and it does not describe the magnitude of the effect.
Repeated binary measurements
The endpoint description refers to yes-or-no classifications at eight assessments. In general, observations from the same participant over time may be correlated: one participant’s measurements are not necessarily statistically independent of that participant’s other measurements. Statistical analyses can account for this dependence, but the appropriate approach depends on the data structure and analysis question. The registry names logistic regression but does not say whether the model accounted for within-participant correlation, whether it treated each assessment as an observation, or how it combined observations. Those details are necessary to evaluate the modeling assumptions fully.
Over-dispersion is a general concern when observed variation is greater than a model assumes. For binary outcomes, unmodeled clustering or dependence can affect uncertainty estimates. This is a general methodological consideration, not a claim that over-dispersion occurred in this trial. The registry record does not report a test or adjustment for over-dispersion, nor does it specify a repeated-measures model.
Endpoint and unit of analysis
The primary outcome entry defines the measure as the percentage of blood samples that were undetectable over the assessments. The summary instead describes the percentage of participants with undetectable viral loads. These descriptions may correspond to different ways of aggregating repeated observations, but the record does not say how they were reconciled. The outcome entry also says the classification was yes or no at each assessment. Clarification of whether the reported regression analyzed participants, samples, assessments, or an aggregate would help readers understand the estimand—the precise quantity the analysis was intended to estimate.
The record identifies the primary analysis population as intent to treat. In general, an intent-to-treat analysis aims to retain participants in the groups to which they were randomized, regardless of adherence to the assigned intervention. The registry does not describe how that principle was implemented for incomplete outcome records, nor does it specify the number of participants contributing data at each assessment.
What is not specified
The registry does not report the model specification, covariates, handling of repeated measurements, missing-data method, or diagnostic checks. It does not report a sample-size justification or interim-analysis plan. Those omissions do not invalidate the reported result on their own, but they limit independent assessment of the analysis and its assumptions. The numerical result should therefore be read as the sponsor’s posted logistic-regression finding, accompanied by the precision information the registry gives, rather than as a fully reproducible analysis description.
10. Analyses Reported by the Sponsor
| Method | Estimate | 95% CI | P-value |
|---|---|---|---|
| Regression, Logistic | Odds Ratio (OR) 7.1 | 2.7 to 18.8 | < 0.001 |
The registry’s reported analysis is a logistic regression comparing the incentive group with the usual-care group. It gives an odds ratio of 7.1, a 95% confidence interval from 2.7 to 18.8, and p < 0.001. This is the sponsor’s posted statistical result, and it is the relevant inferential estimate available in the registry record.
No unadjusted recalculated estimate for this two-arm endpoint is reported. The registry identifies the outcome as a count-other type and notes that values are missing or not estimable for a two-arm comparison. Therefore, there is no separate recalculated odds ratio or confidence interval to compare numerically with the sponsor’s regression result. The arm-level values, 70.4 and 42.5, do not by themselves provide the information needed to reproduce the model-based estimate or its uncertainty.
The registry does not report the model specification or explain the analysis unit for the repeated assessments. Consequently, the posted result can be described accurately, but its detailed relationship to the underlying assessment-level data cannot be reconstructed from the record. No discrepancy between a reported sponsor analysis and a recalculated estimate is identified; a recalculated estimate is not available for this comparison.
11. Multiplicity, Missing Data and Analysis Populations
The registry lists five secondary outcomes in addition to the primary endpoint. They concern biologically verified and self-reported adherence to antiretroviral medications, maintaining prescriptions, retention in HIV medical care, and post-intervention effects. The record lists one analysis and does not describe a multiplicity adjustment, a hierarchy for testing outcomes, or a procedure for prioritizing confirmatory and exploratory analyses. Whether any such plan existed is not reported in the registry record.
Multiplicity is a general statistical issue that arises when several hypotheses are tested. As the number of tests increases, the chance of at least one apparently notable result can increase if each test is interpreted without accounting for the others. This general concern does not establish that the findings in this trial are misleading; it means that the record’s lack of a stated multiplicity approach limits interpretation across the set of outcomes. The reported primary p-value should be considered in relation to the primary endpoint, while claims across multiple outcomes would require more information about the analysis plan.
The primary population is identified as intent to treat. The registry does not report how missing outcome measurements were handled, whether participants with incomplete follow-up were included in particular analyses, or how many observations were available at each assessment. It also does not describe imputation, sensitivity analyses, or reasons for missing data. These details matter because the primary endpoint involves repeated assessments over two years.
The study summary describes assessments during the two-year intervention and additional assessments during the following year, while the primary endpoint is limited to the eight three-month assessments during the intervention. The registry does not report a detailed analysis plan for follow-up outcomes or explain how post-intervention data relate to the primary analysis. Further information about the handling of missing data, analysis populations for secondary outcomes, and any multiplicity strategy is not reported in the registry record.
12. 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 |
|---|---|---|---|
| Incentive Group | 10 | 52 | 19.2% |
| Usual Care Group | 1 | 50 | 2.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Incentive Group | 4 of 52 |
| Usual Care Group | 3 of 50 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Incentive Group | 0 of 52 |
| Usual Care Group | 0 of 50 |
Most frequent serious adverse event terms
| Event term | Organ system | Incentive Group | Usual Care Group |
|---|---|---|---|
| Pneumonia | General disorders | 2 of 52 | 0 of 50 |
| Psychiatric treatment | Nervous system disorders | 2 of 52 | 0 of 50 |
| Congestive heart failure | Cardiac disorders | 0 of 52 | 1 of 50 |
| Depression | Nervous system disorders | 1 of 52 | 0 of 50 |
| Hallucinations | Nervous system disorders | 1 of 52 | 0 of 50 |
| Infection | Infections and infestations | 1 of 52 | 0 of 50 |
| influenza | Gastrointestinal disorders | 1 of 52 | 0 of 50 |
| Joint pain | Musculoskeletal and connective tissue disorders | 1 of 52 | 0 of 50 |
| Kidney failure | General disorders | 1 of 52 | 0 of 50 |
| Urinary problems | General disorders | 1 of 52 | 0 of 50 |
Serious events with the highest arm-level rate: pneumonia (3.8%), psychiatric treatment (3.8%), congestive heart failure (2.0%), depression (1.9%), hallucinations (1.9%).
The serious adverse-event figures are 10 of 52 participants in the incentive group and 1 of 50 in the usual-care group. Deaths are reported for 4 participants in the incentive group and 3 in the usual-care group. The registry lists no other adverse events in either group: 0 of 52 and 0 of 50, respectively. These are descriptive counts from the safety record, not estimates of causal effects.
The listed serious-event terms and percentages are pneumonia at 3.8%, psychiatric treatment at 3.8%, congestive heart failure at 2.0%, depression at 1.9%, hallucinations at 1.9%, and infection at 1.9%. The registry does not explain how these terms map to the group counts, whether a participant could contribute more than one event, or whether the percentages use participants or events as their denominator. They should therefore be read as the posted serious-event listings, not as a complete group-by-group breakdown.
The record does not state whether serious events or deaths were judged related to an intervention, and the counts alone do not establish cause. It also does not provide a comparative safety analysis or uncertainty estimates for these figures. The difference in reported counts should be interpreted cautiously given the limited information about event definitions, ascertainment, and attribution.
13. What the Result Does, and Does Not, Mean
The registry reports that the incentive group had an arm-level endpoint value of 70.4 and the usual-care group had a value of 42.5. It also reports a logistic-regression odds ratio of 7.1, with a 95% confidence interval from 2.7 to 18.8 and p < 0.001. Together, these figures describe a statistically significant reported comparison, with the confidence interval indicating uncertainty around the odds-ratio estimate.
The result does not mean that the probability of an undetectable viral load was 7.1 times as large in the incentive group. An odds ratio is on the odds scale, and the registry does not provide enough analysis detail to convert it to a probability comparison. The reported arm values are percentages according to the endpoint’s stated unit, but the record does not clarify how the repeated blood-sample assessments were aggregated or how those values relate to the participant-level wording in the study summary.
The posted result does not establish the mechanism behind the group difference, nor does it establish how the intervention would perform in settings beyond the trial. The record does not report eligibility criteria or participant characteristics that would allow readers to assess applicability in detail. The enrollment figure is 102, while the summary describes N = 200; the record does not explain the difference.
The result also does not answer all questions about persistence after the intervention. Post-intervention effects appear among the secondary outcomes, but the registry does not provide those outcome results in the registry record described. Nor does the primary result settle the safety interpretation: adverse-event counts are reported, but the record does not give attribution or a comparative safety analysis.
In general, a registry result is most informative when the endpoint, analysis population, model, and missing-data procedures are clearly specified. Here, the record provides a primary endpoint description, arm-level values, and a regression estimate, but leaves several analytic details unreported. The finding can be described as the posted statistical comparison without extending it to claims that the registry does not support.
14. Why This Trial Matters Statistically
This trial raises several important statistical interpretation issues in a compact example. The endpoint is measured repeatedly: a yes-or-no viral-load classification at eight three-month assessments. The primary outcome entry then describes a percentage of blood samples, while the study summary describes a percentage of participants. Those are not necessarily interchangeable summaries. Clear identification of the unit of analysis and the way repeated measurements are combined is important for understanding what an effect estimate represents.
The registry reports an odds ratio from logistic regression, but does not describe the model structure or whether the analysis accounted for dependence among repeated observations from the same participant. In general, repeated measurements can carry information about change over time, but they also require careful treatment of correlation. This makes the missing analysis detail relevant to both the interpretation of the estimate and the precision conveyed by its confidence interval.
The record also illustrates why it is useful to distinguish a reported inferential analysis from an arithmetic comparison of arm values. The arm-level values and the model-based odds ratio are different statistical summaries; the latter cannot be reproduced from those values alone. No recalculated two-arm estimate is available in the registry record, so the sponsor’s logistic-regression result is the posted inferential finding.
Finally, the record lists multiple secondary outcomes and safety counts but gives limited information about multiplicity, missing assessments, and event attribution. Recognizing these boundaries helps readers separate the primary reported comparison from broader conclusions about follow-up, secondary outcomes, and safety. The statistical value of a result depends not only on its point estimate and p-value, but also on a clearly defined estimand and transparent analysis procedures.
15. 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.
Several trial-specific limitations arise from information not reported in the registry record. The primary endpoint is described in two ways: the summary refers to a percentage of participants with undetectable viral loads, while the primary outcome entry refers to a percentage of blood samples that were undetectable. The latter specifies eight assessments with yes-or-no classifications, but the record does not explain how the measurements were combined to form the posted arm values or regression outcome.
The registry identifies logistic regression but does not report the model specification, covariates, or handling of repeated observations. It does not say whether the analysis accounted for correlation among measurements from the same participant. The approach to missing assessments, the number of observations at each time point, and any sensitivity analyses are also not reported. These omissions limit independent evaluation of the result’s assumptions and precision.
The record gives an enrollment of 102, whereas the study summary describes N = 200. It does not explain the difference or provide participant flow details. Eligibility criteria, participant characteristics, and randomization procedures are not reported in the registry entries. Without those details, it is difficult to assess how closely the analyzed population reflects the population described in the summary.
The registry lists five secondary outcomes but does not report a multiplicity strategy or a hierarchy of outcomes. It also does not provide the secondary results in the record details. For safety, serious adverse-event counts, deaths, and listed terms are present, but event attribution and the relationship between the terms and group counts are not explained. These limitations call for a bounded reading of the posted primary comparison rather than assumptions about unreported design or analysis choices.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Suppression of HIV 1 RNA in People Living With HIV — NCT02363387.
- Registry record last updated 2023-04-24; status last verified 2023-04.
- Results first posted 2023-04-24.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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19. Record Summary
This completed randomized, parallel-group trial compared incentives for viral suppression plus standard HIV medical care with standard care alone. The registry records 102 enrolled participants, while the study summary states N = 200; the difference is not explained. The primary endpoint concerns undetectable viral-load samples, defined as less than 200 copies/mL, across eight three-month assessments during two years.
The incentive group’s posted arm value is 70.4 and the usual-care group’s is 42.5. The reported logistic-regression comparison is an odds ratio of 7.1, with a 95% confidence interval from 2.7 to 18.8 and p < 0.001. The registry does not describe the model specification, repeated-measure handling, or missing-data procedures. Five secondary outcomes are listed. Serious adverse events and deaths are reported by group, but attribution is not stated.