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 Diazepam Use With Standard Management for Acute Low Back Pain (NCT02646124), a randomized phase 2, phase 3 study. The primary outcome is Change in Functional Impairment as Measured by the Roland Morris Disability Questionnaire.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02646124 |
| Phase | Phase 2, Phase 3 |
| Condition | Low Back Pain |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Triple |
| Enrollment | 114 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Montefiore Medical Center |
| Results posted | Yes |
2. Clinical Question
Population
People with acute, non-traumatic, non-radicular low back pain treated in an emergency department. The registry record does not report further eligibility details or a more specific description of the analyzed population.
Intervention
Naproxen plus diazepam. The registry record identifies naproxen and diazepam as the drugs used in this group.
Comparator
Naproxen plus placebo. This comparison keeps naproxen as the standard management in both groups while varying whether diazepam or placebo is added.
Primary question
How did functional impairment, measured with the Roland Morris Disability Questionnaire, change between baseline and one week after emergency-department discharge in each group? The posted primary results give group means and confidence intervals; a direct between-group estimate or test is not reported in the registry record.
The trial addresses whether adding diazepam to naproxen is associated with a different short-term functional outcome than adding placebo to naproxen in acute low back pain without radicular symptoms. Its stated motivation is persistent pain and functional limitations after an emergency-department visit. The comparison is therefore about the added medication, not naproxen versus no treatment.
Other questions in the registry record concern pain severity, use of analgesic medication after discharge, and satisfaction with treatment. These outcomes provide different perspectives on the short-term experience, but they do not replace the primary functional measure. One listed secondary outcome—analgesic use within the previous 72 hours—does not have posted results in the registry record.
The primary outcome is recorded as change from baseline to one week after discharge. The score’s direction matters: the RMDQ measures impairment, with higher scores indicating greater impairment, while change is calculated by subtracting the one-week score from baseline. Thus, a positive change indicates a lower score at follow-up. The registry record does not report the between-group statistical analysis for this change, so the group summaries alone do not establish whether the groups differed.
3. Trial Design
The registry describes a randomized, triple-masked, parallel-group comparative effectiveness study. It lists phase 2 and phase 3 and an enrollment of 114. The study status is completed. The sponsor is Montefiore Medical Center. The recorded study start is 2015-06, and primary completion is recorded as 2016-02.
Participants were assigned to naproxen plus diazepam or naproxen plus placebo. This design holds the naproxen component in common and compares the additional diazepam with a placebo. The parallel model means the registry describes participants as assigned to one group rather than switching between the study groups. Random allocation can help balance measured and unmeasured characteristics on average, but it does not guarantee balance in a particular trial, and the registry record does not report the allocation method or allocation concealment details.
The registry labels masking as triple, but it does not identify which roles were masked or describe how masking was maintained. It also does not report the protocol’s planned analysis methods, sample-size justification, interim analyses, or a detailed account of follow-up and retention. These omissions limit what can be concluded about trial conduct from the registry record alone.
The primary outcome was change in RMDQ score between baseline and one week after emergency-department discharge. Secondary outcomes include moderate or severe pain on an ordinal scale, analgesic use within the previous 24 hours, analgesic use within the previous 72 hours, and satisfaction with treatment. Posted secondary results are available for the pain measure, 24-hour analgesic use, and treatment satisfaction. Results for the 72-hour analgesic-use outcome are not reported in the registry record.
The registry reports group-level primary outcome means and 95% confidence intervals. It does not post a primary between-group estimate or a formal primary comparison. No formal analyses are listed in the registry results. Consequently, the design description and the outcome summaries should be kept distinct: randomized assignment describes the intended comparison, while the posted summaries do not by themselves provide a full comparative 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
| Stage | Diazepam | Placebo |
|---|---|---|
| STARTED | 57 | 57 |
| COMPLETED | 57 | 55 |
| NOT COMPLETED | 0 | 2 |
Reasons for not completing this period:
| Reason | Diazepam | Placebo |
|---|---|---|
| Lost to Follow-up | 0 | 2 |
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 | Diazepam | Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 57 | 57 | 114 | |
| Age, Continuous | Years | 34 (SD 12) | 38 (SD 12) | 36 (SD 12) |
| Sex: Female, Male: Female | Participants | 27 | 24 | 51 |
| Sex: Female, Male: Male | Participants | 30 | 33 | 63 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: United States | Participants | 57 | 57 | 114 |
| Duration of Back Pain Prior to Study | hours | 72 (24 to 108) | 48 (12 to 96) | 48 (24 to 96) |
6. Primary Endpoint
The registry lists the primary outcome as Change in Functional Impairment as Measured by the Roland Morris Disability Questionnaire, measured over Between baseline and one week after emergency department discharge.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | units on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change in functional impairment measured with the Roland Morris Disability Questionnaire (RMDQ). This instrument has 24 items about the effect of low back pain on daily life. Each item is answered yes or no, and the total score ranges from 0 to 24. A higher score indicates greater impairment and poorer quality of life. The registry describes the instrument as most sensitive for people with mild to moderate disability due to acute, sub-acute, or chronic low back pain.
Change is defined as the baseline score minus the score one week after emergency-department discharge. With that subtraction order, a positive change corresponds to a lower RMDQ score at follow-up than at baseline. Reporting change can describe how the measure shifted over the follow-up period, rather than reporting the follow-up score alone.
The endpoint is relevant to a trial focused on function after an emergency-department visit: pain intensity and daily activity limitations are related but not interchangeable outcomes. The RMDQ provides a structured measure of disability in everyday activities. The registry’s posted primary results give a mean change for each treatment group and a 95% confidence interval for each mean. They do not include a direct estimate of the difference between groups, so they cannot on their own quantify the added effect associated with diazepam relative to placebo.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary summaries are identical at the reported precision: the mean change in RMDQ score is 11.0 units in the diazepam group and 11.0 units in the placebo group. Each group’s 95% confidence interval is 9.0 to 13.0 units. These are within-group summaries. The registry record does not report a between-group contrast, its confidence interval, or a primary hypothesis-test result.
Because change is baseline score minus the one-week score, a positive mean change represents a decrease in impairment scores on average. The summaries therefore describe a positive average change in each group over the measured interval. They do not show how much change would have occurred without either assigned regimen, and they do not isolate the effect of diazepam from other influences over time. The shared naproxen treatment is also part of both groups’ care.
Equal rounded means do not prove that the groups are equivalent. The values are reported to one decimal place, and the registry record does not provide the underlying individual observations or a formal comparative analysis. Likewise, the matching confidence intervals around the group means should not be treated as a confidence interval for the difference. A comparison needs its own estimate and uncertainty calculation; overlap or equality of separate group intervals is not a substitute for that calculation.
The secondary results offer a mixed numerical pattern rather than a consistent signal across outcomes. The recalculated, unadjusted risk-difference intervals for the three posted secondary comparisons include no difference. Their unadjusted p-values do not cross the 0.05 threshold used in the planning illustration. These calculations are not reported analyses from the registry, and they should be read as exploratory summaries rather than confirmatory evidence. There are no registry-listed formal analyses to provide an alternative adjusted estimate.
The primary outcome is the most direct measure of the trial’s stated functional question, but its comparative result is missing from the posted record. The available primary data support a description of the group means and their precision; they do not support a definitive statement about a treatment-group difference. The secondary outcomes likewise provide limited comparative evidence, especially because they are multiple outcomes and no multiplicity procedure is reported.
Precision is important alongside the direction of an estimate. A confidence interval describes uncertainty around an estimate under the analysis assumptions; it is not a guarantee that the true value lies in that particular interval. For the primary endpoint, the posted intervals concern each group’s mean change, not the contrast of interest. The absence of a contrast interval leaves the precision of the treatment comparison unreported.
Safety counts should also be interpreted descriptively. No serious adverse events or deaths are posted in either group, while other adverse events are recorded. These counts do not establish that risks are identical, and the registry does not report enough detail about event definitions, follow-up, or formal comparisons to support a broader safety conclusion.
9. Statistical Methods Explained
For a continuous outcome such as RMDQ change, a mean describes the center of the observed values. A confidence interval around a mean conveys the statistical uncertainty in estimating the group’s underlying mean, given the analysis assumptions. It does not show the spread of individual participant scores, and it does not automatically compare two groups. In this trial, the registry reports the mean and 95% confidence interval separately for each group. It does not report a primary treatment contrast or a confidence interval for that contrast.
What does the primary confidence interval represent?
The primary intervals of 9.0 to 13.0 units are attached to each group’s mean change. They indicate uncertainty about those group means, not uncertainty about the difference between the diazepam and placebo groups. To answer the comparative question directly, an analysis would need to estimate a between-group difference and its uncertainty. The registry record does not report such an analysis. Separate group intervals cannot be combined informally to create a valid interval for the contrast.
The measure’s construction also shapes interpretation. RMDQ scores range from 0 to 24, with higher scores representing greater impairment. The recorded change subtracts the one-week score from baseline, so positive values correspond to a reduction in the score. This direction is the reverse of a change calculated as follow-up minus baseline. Clear attention to the subtraction order prevents reversing the meaning of the reported change.
How should the secondary comparisons be read?
The posted secondary outcomes are binary in the registry results: each reports a participant count in each group. The accompanying recalculated comparisons express the difference in the observed proportions as a risk difference. A risk difference of zero represents no difference in the proportions under that definition; an interval spanning zero is compatible with no difference as well as with differences in either direction. The reported recalculations are unadjusted, so they do not account for covariates or other design features beyond the summary data used in the calculation.
The p-values attached to those secondary comparisons are also unadjusted. A p-value assesses how compatible the observed data are with a specified null model, conditional on the analysis assumptions; it is not the probability that the null hypothesis is true, nor a measure of clinical importance. Because several outcomes are considered, interpreting each unadjusted p-value as if it were the sole planned test can overstate the strength of evidence. The registry record does not report a multiplicity adjustment or a prespecified hierarchy for these secondary outcomes.
Why are planning calculations not trial results?
The sample-size illustrations use the observed effect as a planning reference and apply a two-sided significance level of 0.05, equal allocation between groups, and a normal approximation. Rows for planning for 100%, 75%, and 50% of the observed effect describe hypothetical future-study sizes under those assumptions. They are not the enrollment target or power calculation documented for this completed trial. The protocol’s design assumptions and sample-size justification are not reported in the registry record.
Such planning values are sensitive to the effect chosen. Smaller target effects require more participants to distinguish them from no difference under otherwise fixed assumptions. This is a general statistical relationship, not a claim that a particular future study will attain the stated operating characteristics. Planning illustrations are not observed power, and they cannot show whether the completed trial was adequately powered. The registry record does not state that these calculations were part of the trial’s original design.
What can be inferred from the posted analysis record?
No formal analyses are listed in the registry results, and the primary comparison is not reported. The simple secondary recalculations are useful descriptive aids but do not replace a sponsor-reported analysis. The registry record does not report whether the primary analysis adjusted for baseline RMDQ, how any departures from assumptions were handled, or whether missing outcomes were imputed. It also does not report the analysis population, such as whether participants were analyzed according to randomized assignment or another rule.
In general, randomization supports causal interpretation when assignment, follow-up, and analysis are handled appropriately. Missing outcomes, departures from assigned treatment, and selective reporting can affect that interpretation. Those procedures and details are not reported in the registry record, so they cannot be evaluated from the posted information. The safest statistical reading is to distinguish what is directly reported—the group means, intervals, counts, and safety figures—from what is not—the formal primary contrast, its uncertainty, and the analysis procedures behind it.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists several secondary outcomes alongside the primary functional endpoint. When multiple outcomes are tested, the possibility of at least one apparently positive result by chance can rise. Statistical approaches can address this through a prespecified hierarchy, adjustment of significance levels, or other multiplicity procedures. The registry record does not report whether any such approach was planned or used. The recalculated secondary p-values are unadjusted and should not be treated as confirmatory evidence across the outcome set.
The record also does not describe missing-data handling. It does not state how participants with an unavailable one-week assessment were handled, whether imputation was used, or what assumptions would support an analysis of incomplete outcomes. Group counts in the posted results do not by themselves explain the completeness of follow-up or establish that every randomized participant contributed to each outcome.
The analysis population is not reported in the registry record. In particular, it does not specify whether the primary analysis followed randomized assignment, included only participants who completed treatment, or used another definition. The protocol, deviations from assigned treatment, and analysis-set details are also not reported. These details matter because excluding participants or using different analysis populations can change the interpretation of a randomized comparison.
Interim analyses, stopping rules, and the original sample-size justification are not reported in the registry record. Their absence from the record should not be read as evidence that they did or did not occur. Without these details, readers cannot assess whether the reported information reflects the planned analysis or evaluate how incomplete follow-up and multiple outcomes were addressed.
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 |
|---|---|---|---|
| Diazepam | 0 | 57 | 0.0% |
| Placebo | 0 | 55 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Diazepam | 0 of 57 |
| Placebo | 0 of 55 |
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 |
|---|---|
| Diazepam | 12 of 57 |
| Placebo | 8 of 55 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Diazepam | Placebo |
|---|---|---|---|
| Other | General disorders | 6 of 57 | 6 of 55 |
| Drowsy | Nervous system disorders | 4 of 57 | 1 of 55 |
| Stomach irritation | Gastrointestinal disorders | 1 of 57 | 1 of 55 |
| Dizzy | Nervous system disorders | 1 of 57 | 0 of 55 |
The registry posts zero serious adverse events in each group and zero deaths in each group. It also records other adverse events in both groups. These figures are counts, not estimates of comparative risk adjusted for follow-up or other factors. They do not establish that the groups have identical safety profiles or rule out uncommon harms.
The registry record does not report the definitions used for serious and other adverse events, the period over which events were collected, event severity or relatedness, or a formal statistical comparison. It does not provide serious-event terms. The safety information is therefore best read as a limited descriptive account of the events posted in the registry, not as a comprehensive assessment of safety.
Differences in event counts can be difficult to interpret without knowing ascertainment procedures, exposure, and completeness of follow-up. Zero observed serious events is not proof that the underlying risk is zero. The posted counts are useful for understanding what was recorded, but they do not support broader conclusions about comparative safety.
12. What the Result Does, and Does Not, Mean
The primary results describe a mean reduction in RMDQ score in each treatment group over the period from baseline to one week after emergency-department discharge. The registry reports equal group means at the stated precision and equal group confidence intervals. This is a description of the posted data, not a formal finding that the treatments are equivalent. No primary between-group estimate, confidence interval for that estimate, or test result is reported.
The comparison concerns adding diazepam to naproxen rather than comparing naproxen with no treatment. Since both groups received naproxen, the primary summaries do not establish what would have happened without naproxen or without the study regimen. They also do not isolate the effects of time, other care, or participant expectations from the observed within-group change.
Secondary outcomes add information about symptoms and participant experience, but the available recalculated comparisons are unadjusted and uncertain. The registry record does not report a multiplicity plan, analysis population, or missing-data strategy. These gaps limit confidence in drawing broad conclusions from the secondary results. The outcome for analgesic use within the previous 72 hours is listed but has no posted result.
These data should not be interpreted as clinical advice or as proof that either regimen is effective or ineffective. A trial’s observed summaries are not a guarantee of an individual’s outcome. The posted record supports a narrow account of group-level observations over the reported follow-up, while leaving the principal between-group estimate and several analytical details unavailable.
More complete interpretation would require the comparative primary analysis, its uncertainty interval, and details of how outcomes and participants were handled. Without those items, it is not possible to determine from the registry record how precisely the treatments differed on the primary endpoint.
13. Why This Trial Matters Statistically
This trial illustrates an important distinction in clinical statistics: group summaries are not the same as a treatment comparison. Equal reported means and confidence intervals describe the groups separately, but the central question is the difference between groups and the uncertainty around that difference. A reader cannot recover that comparison simply by visually comparing the separate intervals.
It also shows why outcome direction and definition matter. The RMDQ score increases with impairment, but the trial defines change as baseline minus follow-up. A positive change therefore has a different sign interpretation than a follow-up-minus-baseline change. Clear reporting of the scale, time point, and subtraction order is essential for meaningful reading.
The secondary outcomes demonstrate another common issue: multiple unadjusted comparisons can generate a scattered set of results that are easy to overinterpret. Confidence intervals and multiplicity context are needed alongside counts and p-values. Planning illustrations can help frame future research, but they are not evidence of the completed trial’s power and are not its observed outcomes.
Finally, the registry record separates what was posted from what remains unavailable. Reporting the primary contrast, analysis population, missing-data approach, multiplicity plan, and safety definitions would make the findings easier to assess and reproduce. These considerations matter beyond this trial: transparent comparative estimates and clear analysis methods are central to judging the precision and limits of clinical evidence.
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 most important limitation of the posted results is that the registry gives primary group means and confidence intervals without a direct between-group estimate. The main comparative question is therefore not answered by the primary results as recorded. The reported group summaries are rounded, and the individual-level outcome data are not included in the registry record.
The available follow-up for the primary outcome is one week after emergency-department discharge. These results do not describe outcomes beyond that assessment. The registry record does not report participant eligibility details beyond acute, non-traumatic, non-radicular low back pain, nor does it give further information about the enrolled population. Generalizability to people outside the described setting and condition cannot be evaluated fully from the posted record.
Several analysis details are also absent: the analysis population, missing-data methods, protocol deviations, primary comparison method, and multiplicity handling are not reported. The registry does not provide results for the listed 72-hour analgesic-use outcome. Secondary comparisons are recalculated and unadjusted rather than registry-reported formal analyses, which limits their evidential weight.
Safety information is similarly limited. Serious-event and death counts are posted, but definitions, collection period, relatedness, and formal comparisons are not reported. The absence of these details does not establish that events were not assessed; it means the registry record does not provide enough information to evaluate their ascertainment or comparative meaning.
These limitations concern the information available in the registry record, not necessarily the full trial documentation. The protocol and a fuller statistical report are not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Diazepam Use With Standard Management for Acute Low Back Pain — NCT02646124.
- Registry record last updated 2018-08-01; status last verified 2018-07.
- Results first posted 2018-07-03.
- 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
NCT02646124 is a completed randomized, triple-masked, parallel-group study of diazepam added to naproxen for acute, non-traumatic, non-radicular low back pain. The registry lists phase 2 and phase 3, enrollment of 114, and Montefiore Medical Center as sponsor. The recorded study start is 2015-06, with primary completion in 2016-02.
The primary outcome is RMDQ change from baseline to one week after emergency-department discharge. The registry reports group means and 95% confidence intervals but no primary between-group analysis. Three secondary outcomes have posted results; the listed 72-hour analgesic-use outcome does not. Safety counts include no posted serious adverse events or deaths in either group. Details of the analysis population, missing-data handling, and multiplicity procedures are not reported in the registry record.