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 Pilot Testing of a Behavioral Intervention for Chronic Pain in Individuals With HIV (NCT02824562), a randomized na study. The primary outcome is Intervention Feasibility: Median Number of Study Intervention Sessions Attended by Participants.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02824562 |
| Phase | NA |
| Condition | Chronic Pain |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 44 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Pittsburgh |
| Results posted | Yes |
2. Clinical Question
Population
Adults with chronic pain who are living with HIV were the intended population. The registry record describes the intervention as tailored to this population, but does not report further eligibility criteria or participant characteristics.
Intervention
The intervention combined treatment as usual with a chronic-pain self-management program. The program was planned to include six one-on-one sessions and six group sessions, facilitated by a trained interventionist; a peer also facilitated the group sessions.
Comparator
The control group received treatment as usual: the standard of care for chronic pain, with participants able to discuss pain with their providers at their discretion. The registry record describes this care as variable and does not detail its components.
Primary question
The primary question concerned feasibility: how many study intervention sessions participants attended during the 16 week intervention period. The endpoint was specified as the median number of sessions attended, with an inter-quartile range. The registry record does not report those values. A secondary outcome concerned completion of outcome assessments within one month, but its result is also not reported in the registry record.
3. Trial Design
This was a randomized, single-masked, parallel-group pilot study listed as completed. The registry record lists phase as NA. It records enrollment of 44 participants and identifies chronic pain as the condition under study. The study start is recorded as 2016-07, with primary completion on 2017-06-01.
The intervention group was assigned treatment as usual plus a chronic-pain self-management program. The plan described six individual sessions and six group sessions over a 16 week intervention period. Group sessions were to be facilitated by a trained interventionist and a peer. The control group received treatment as usual, described as standard care that allowed participants to discuss chronic pain with providers at their discretion. Details of the standard-care components are not reported in the registry record.
The primary endpoint was a feasibility measure: the median number of intervention sessions attended, with an inter-quartile range. The outcome population is described as all 22 participants assessed. A secondary outcome was the number and percentage of participants completing outcome assessments within one month. The registry record does not report numerical results for either outcome, nor does it report a comparative estimate between groups.
Randomization assigns participants to study groups by chance. In general, this can help limit systematic differences between groups, though it does not guarantee that groups are alike in every respect. The record says the study was single-masked, but does not identify who was masked or describe how masking was implemented. These omissions limit what can be said about the conduct of masking. The record also does not report the sequence-generation or allocation-concealment procedures.
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 | Intervention | Control |
|---|---|---|
| STARTED | 22 | 22 |
| COMPLETED | 19 | 17 |
| NOT COMPLETED | 3 | 5 |
Reasons for not completing this period:
| Reason | Intervention | Control |
|---|---|---|
| Lost to Follow-up | 3 | 4 |
| Death | 0 | 1 |
Analysis population for the primary outcome, as defined in the registry: All 22 participants were assessed.
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 | Intervention | Control | Total |
|---|---|---|---|---|
| Participants analysed | 22 | 22 | 44 | |
| Age, Continuous | years | 51 (48 to 55) | 51 (46 to 57) | 51 (46 to 57) |
| Sex: Female, Male: Female | Participants | 11 | 14 | 25 |
| Sex: Female, Male: Male | Participants | 11 | 8 | 19 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| 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 | 19 | 19 | 38 |
| Race (NIH/OMB): White | Participants | 3 | 2 | 5 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 1 | 1 |
| Number of participants with undetectable viral load (blood test, measured in copies/mL) | Participants | 21 | 21 | 42 |
6. Primary Endpoint
The registry lists the primary outcome as Intervention Feasibility: Median Number of Study Intervention Sessions Attended by Participants, measured over From baseline throughout the entire 16 week intervention period.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Inter-Quartile Range |
| Unit | Study Sessions |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint measures intervention participation: the median number of study sessions attended during the intervention period, with an inter-quartile range. Participants were expected to attend six one-on-one sessions and six group sessions; the record describes 12 sessions as the maximum per participant if all were attended. The observation period ran from baseline throughout the entire 16 week intervention period.
General: a feasibility endpoint asks whether a study procedure or intervention can be delivered and assessed as intended. Session attendance can describe participants’ engagement with the planned program. It does not, by itself, establish a change in pain or another clinical outcome. The median describes the central value when attendance is ordered, while the inter-quartile range describes the spread of the middle portion of observed values. These summaries can be useful when attendance is uneven or has a skewed distribution.
The registry record specifies the summary measure and the assessed population, but does not report the median attendance or its inter-quartile range. It therefore does not allow readers to quantify attendance or its variability. The rationale for selecting this particular endpoint beyond its feasibility focus is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a pilot study designed to test the feasibility of a behavioral intervention for chronic pain in people with HIV. Its primary outcome is session attendance, not a direct comparison of pain or other clinical outcomes. The design and outcome definition indicate what the study intended to assess, but the record does not report the primary outcome values. In particular, the median number of sessions attended and its inter-quartile range are not reported in the registry record.
The secondary outcome concerns completion of outcome assessments within one month. Although that outcome is identified, its number and percentage are not reported in the registry record. The record also lists no analyses. No between-group estimate, confidence interval, p-value, or other result for these outcomes is reported in the registry record. The posted information therefore does not support a quantitative interpretation of intervention attendance, assessment completion, or differences between the randomized groups.
General: a confidence interval expresses uncertainty around an estimated quantity; its width reflects how precisely that quantity has been estimated under the analysis assumptions. Without an estimate and its uncertainty interval, readers cannot assess the precision of an outcome estimate. A p-value, if reported, would address compatibility of observed data with a specified statistical model and null hypothesis; it would not on its own describe the size or practical importance of an effect. Neither type of result is available for the study outcomes in the registry record.
The recorded enrollment was 44, and the primary outcome population is described as all 22 participants assessed. The record does not provide a participant-flow account, explain the relation between enrollment and endpoint assessment, or state whether missing outcome data occurred. Consequently, attendance summaries cannot be assessed for completeness or potential selection effects from the registry information alone.
The safety record reports zero serious adverse events among 22 participants at risk in each group. It also reports zero other adverse events among 22 participants at risk in each group. Deaths are recorded as zero in the intervention group and one in the control group. These are descriptive counts; the registry record does not report causes, timing, attribution, or a statistical comparison. The counts should not be taken as evidence about comparative risk.
Overall, the registry record supports describing the study’s design, planned feasibility measures, and posted safety counts. It does not support a conclusion about how many sessions participants attended, how often assessments were completed, or whether the intervention changed clinical outcomes relative to control. The intervention’s effectiveness is not established by the information reported in the registry record.
9. Statistical Methods Explained
General: statistical methods should follow the question being asked and the kind of outcome being measured. A feasibility question about attendance differs from a clinical-effect question about pain. The primary endpoint in this study is the number of intervention sessions attended, summarized by a median and inter-quartile range. This is a descriptive approach to the distribution of attendance, rather than a model-based estimate of a treatment effect. The registry record does not report the observed summary values or an inferential analysis.
What does the median describe?
General: the median is the middle observation after values are ordered. It is less influenced by unusually high or low values than the arithmetic mean. The inter-quartile range describes the spread of the central portion of the distribution. Together, these summaries can describe a typical attendance level and its variability without assuming that attendance follows a symmetric distribution. They do not show why some participants attended more or fewer sessions, and they do not by themselves compare the intervention group with the control group.
The record specifies attendance across the 16 week intervention period and says participants were expected to attend six individual sessions and six group sessions, with 12 as the maximum if all sessions were attended. It identifies all 22 participants as assessed for the primary outcome. The actual attendance distribution, median, inter-quartile range, and handling of participants with incomplete attendance information are not reported in the registry record.
How does randomization relate to analysis?
General: random assignment is intended to make treatment allocation independent of participants’ measured and unmeasured characteristics, on average over repeated randomizations. In a particular trial, groups can still differ by chance. A comparative analysis ordinarily needs outcome data from the relevant groups and a clearly defined estimate, together with an account of uncertainty. The registry record identifies a randomized parallel-group design, but does not report a comparative analysis of the primary outcome. The sequence-generation method, allocation concealment, and details of the analysis plan are not reported in the registry record.
The study is listed as single-masked, but the masked party and masking procedures are not reported in the registry record. General: masking can reduce some forms of bias when knowledge of assigned group might affect care, outcome assessment, or reporting. Its implications depend on who is masked and how outcomes are measured. With no description of the masking procedures, those features cannot be evaluated from the registry entry.
What can the secondary outcome show?
The secondary outcome is the number and percentage of participants who complete outcome assessments within one month. General: completion rates describe whether measurement procedures were carried out, and incomplete assessment can affect how representative observed outcome data are. A completion summary does not itself demonstrate a clinical benefit. The registry record does not report the completion counts or percentages, definitions of completion, or how missing assessments were handled.
The registry record lists two outcome measures and zero analyses. It does not report multiplicity procedures, prespecified statistical tests, covariate adjustments, confidence intervals, or p-values. It also does not report a detailed statistical analysis plan. Those details should not be inferred from the randomized design or from the feasibility focus.
How should planning calculations be read?
General: sample-size calculations are planning exercises that depend on assumptions about the effect to detect, variability, significance level, allocation, and analysis method. They are not outcomes observed in the trial. The registry record’s stated planning assumptions describe a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the effect to detect expressed as a stated fraction of the observed effect. Any such calculation is an illustration under assumptions, not observed power and not evidence that an effect was detected. The registry record does not report a trial-specific sample-size justification or the numerical inputs needed to assess one. The primary outcome is listed as a single-arm feasibility summary, and the registry record does not provide a two-group primary-outcome estimate.
General: over-dispersion occurs when observed variability is greater than a statistical model assumes. If it is ignored, standard errors and uncertainty intervals can be misleading. Whether over-dispersion is relevant depends on the outcome model and data; the registry record does not describe a model for the attendance outcome, so no claim about over-dispersion or a correction can be made. More broadly, methods cannot be evaluated fully without the actual outcome data, analysis population, and prespecified analysis details.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists a primary feasibility outcome and a secondary outcome, for two outcome measures in total. The primary measure is the median number of intervention sessions attended, with an inter-quartile range. The secondary measure is the number and percentage of participants who complete outcome assessments within one month. It lists zero analyses, and numerical results for these outcomes are not reported in the registry record.
General: multiplicity arises when several outcomes or statistical tests are considered. If many tests are conducted, the chance of at least one apparently unusual result can increase. Researchers may address this through a prespecified hierarchy, adjustment, or other strategy. The registry record does not report whether any multiplicity procedure was planned or used, and no test results are available to evaluate.
The primary outcome population is described as all 22 participants assessed. This does not specify how many participants were randomized to each outcome population, how missing observations were treated, or whether the analysis followed an intention-to-treat principle. The record does not report missing-data counts, reasons for missingness, imputation methods, or sensitivity analyses. For the secondary outcome, completion is defined in relation to an assessment within one month, but outcome counts and further handling rules are not reported in the registry record.
General: missing data can affect interpretation when participants with observed outcomes differ systematically from those whose outcomes are unavailable. Without counts and handling methods, the extent and possible influence of missingness cannot be assessed. The record also does not define additional analysis populations, such as per-protocol or safety populations, beyond the stated primary outcome population.
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 |
|---|---|---|---|
| Intervention | 0 | 22 | 0.0% |
| Control | 0 | 22 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Intervention | 0 of 22 |
| Control | 1 of 22 |
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 |
|---|---|
| Intervention | 0 of 22 |
| Control | 0 of 22 |
The registry record reports serious adverse events for 22 participants at risk in each group: zero affected participants in the intervention group and zero in the control group. It reports other adverse events for 22 participants at risk in each group, with zero affected participants in both groups. It records zero deaths in the intervention group and one death in the control group. No serious adverse-event terms are listed.
These figures are counts, not estimates of comparative risk. The registry record does not report the cause or timing of the death, whether it was considered related to study participation, or details about how adverse events were collected and classified. It also does not report a statistical comparison of safety outcomes. The counts should therefore be read as the safety information recorded in the registry, without attributing the death to either the intervention or the control care.
General: absence of recorded events in a study does not establish that an event is impossible or that two groups have identical safety profiles. Interpretation depends on the number of participants observed, follow-up, event definitions, and completeness of reporting. Those considerations are especially important when the posted information consists of descriptive counts rather than a comparative analysis.
12. What the Result Does, and Does Not, Mean
The study addresses whether a tailored behavioral chronic-pain program can be piloted among people with HIV. Its intervention was planned to combine treatment as usual with six individual and six group sessions over a 16 week period. The primary outcome focuses on attendance, while the secondary outcome concerns timely completion of outcome assessments. These measures address feasibility and measurement procedures, not directly whether pain improved.
The registry record does not report the median attendance, inter-quartile range, or secondary completion count and percentage. It also lists zero analyses. Therefore, the posted information does not establish how much of the program participants attended, whether outcome assessments were completed as planned, or whether the groups differed on either measure.
Nor does the record provide results for a clinical outcome comparison. No conclusion about changes in pain, comparative effectiveness, or the size and precision of a clinical effect can be drawn from the reported information. A randomized design describes how groups were assigned; it does not substitute for reported outcome estimates and their uncertainty.
The safety counts describe zero serious adverse events and zero other adverse events recorded in each group, alongside one death recorded in the control group and none in the intervention group. The record does not report cause, timing, attribution, or comparative safety analysis. These figures alone do not show that either group had a safer experience.
General: a pilot study can help assess procedures and inform later research, but a feasibility measure is not equivalent to evidence of clinical benefit. Interpretation should distinguish the study’s stated purpose, the outcomes it measured, and the results actually reported. In this case, the registry record supplies the design and outcome definitions but not the numerical feasibility results needed to judge them.
13. Why This Trial Matters Statistically
This trial is statistically notable for separating a feasibility question from a clinical-effect question. The primary endpoint concerns session attendance, and the secondary outcome concerns completion of assessments within one month. Both focus on whether intervention delivery and outcome measurement can be carried out. They are not direct measures of pain improvement.
The intervention has a defined session structure: six one-on-one sessions and six group sessions, with a maximum of 12 sessions if all were attended, over a 16 week period. Measuring attendance can describe participation in that structure. Reporting a median and inter-quartile range would show a central attendance value and how attendance varied, but those values are not reported in the registry record.
The design is randomized, single-masked, and parallel-group, with enrollment of 44. Yet the record lists zero analyses and does not report numerical results for either outcome. This illustrates a key statistical distinction: design features and outcome definitions specify what a study intended to learn, while estimates and uncertainty are needed to interpret what the observations indicate. Without those results, the feasibility question remains unanswered by the posted information.
General: clearly identifying the outcome type helps prevent overinterpretation. Session attendance can inform implementation; assessment completion can inform data collection. Neither alone establishes a change in a clinical condition. Likewise, descriptive safety counts should not be treated as a comparative risk estimate without context and analysis.
The record also leaves important analytic details unreported, including missing-data handling, the analysis plan, and who was masked. Recognizing these gaps is part of statistical interpretation: conclusions should match the evidence that is actually reported, rather than the details a reader might expect a protocol to contain.
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 the primary outcome is that the registry record states the endpoint and assessed population but does not report the median number of sessions attended or the inter-quartile range. The secondary outcome is identified, but its count and percentage are not reported. Without these results, the stated feasibility aims cannot be quantified.
The record lists zero analyses and does not report estimates, confidence intervals, p-values, or a comparison between the randomized groups. It also does not report a detailed statistical analysis plan, sample-size justification, missing-data methods, or sensitivity analyses. The relationship between the 44 enrolled participants and the 22 participants described as assessed for the primary outcome is not explained in the record.
Some design information is incomplete. The study is described as single-masked, but who was masked and how masking was maintained are not reported. Randomization procedures and allocation concealment are also not described. Control care is described as standard care, with discussion of chronic pain with providers at participants’ discretion, and as variable; its components are not detailed in the registry record.
Safety information is limited to event counts. The record does not report the cause or timing of the death, attribution of events, or a comparative analysis. It also does not give further detail about adverse-event ascertainment. These limitations do not establish that a particular problem occurred; they restrict what can be concluded from the registry information.
Finally, the registry record does not report participant characteristics, eligibility criteria beyond the broad intended population, or the clinical outcome results needed to assess treatment effects. The available information supports describing the design and listed measures, but not a quantitative assessment of feasibility or clinical outcomes.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Pilot Testing of a Behavioral Intervention for Chronic Pain in Individuals With HIV — NCT02824562.
- Registry record last updated 2018-10-10; status last verified 2017-12.
- Results first posted 2018-10-10.
- 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
The registry record describes a completed, randomized, single-masked, parallel-group pilot study of a behavioral intervention for chronic pain in people with HIV. Enrollment was 44. The intervention combined treatment as usual with a program planned to include six one-on-one and six group sessions during a 16 week period; control participants received treatment as usual.
The primary outcome was the median number of study intervention sessions attended, with an inter-quartile range. The secondary outcome concerned completion of assessments within one month. Numerical results for either outcome are not reported in the registry record, and the record lists zero analyses. Safety entries report zero serious adverse events and zero other adverse events in each group, and one death in the control group. Cause, timing, and attribution are not reported.
The registry entry documents the intended feasibility questions and study design, but does not provide the outcome summaries or comparative analyses needed to evaluate the results.