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 The Clinical Effects of Montelukast in Patients With Perennial Allergic Rhinitis (0476-265) (NCT00092118), a randomized phase 3 study. The primary outcome is Mean Change From Baseline in Daytime Nasal Symptoms Score Averaged Over the 6-week Treatment Period in Patients With Perennial Allergic Rhinitis.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00092118 |
| Phase | Phase 3 |
| Condition | Rhinitis, Allergic, Perennial |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 1992 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Organon and Co |
| Results posted | Yes |
2. Clinical Question
Population
Patients with a history of perennial allergic rhinitis, an inflammation of the nasal mucous membrane with symptoms that persist throughout the year. The primary efficacy analysis included patients with efficacy measurements at baseline and during treatment, using a modified intention-to-treat approach.
Intervention
Montelukast 10 mg, given during the six-week treatment period. The study record describes the intervention as montelukast and reports the dose in the arm results.
Comparator
Placebo, assigned in a parallel-group design. The study was randomized and double-blind.
Primary question
How did the average change from baseline in daytime nasal symptoms over the six-week treatment period compare across the montelukast and placebo groups? The score averaged patient ratings for congestion, rhinorrhea, and sneezing. Lower scores represent less severe symptoms on the individual rating scale.
The registry record describes a phase 3 study intended to investigate clinical effects in people with perennial allergic rhinitis. The primary outcome is a continuous symptom measure, rather than a count of events or a time until an event. Its posted results report a least-squares mean change for each arm with a 95% confidence interval. They do not report a numerical between-group estimate or a test of the difference. Thus, the arm summaries describe average changes within each group, but by themselves do not provide a direct statistical estimate of the contrast that frames the clinical question.
3. Trial Design
The registry describes a multicenter, randomized, double-blind, placebo-controlled, parallel-group phase 3 study. The sponsor was Organon and Co. The study began in 2003-10, reached primary completion in 2004-05, and has a completed status in the record. Registry enrollment is 1992.
Participants were assigned to montelukast or placebo. The primary outcome was assessed over the six-week treatment period, from baseline through the end of week 6. The posted arm summaries identify the active-treatment group as Montelukast 10 mg and the comparator as Placebo. The record does not describe the details of the randomization sequence, allocation concealment, how blinding was maintained, or whether any participants or assessors were unblinded.
The primary efficacy population is described as modified intention-to-treat: patients with efficacy measurements both at baseline and during treatment were included. The posted primary outcome results report 980 participants for placebo and 1000 for montelukast. The safety summaries use different at-risk counts: 990 for placebo and 1002 for montelukast. The registry record does not explain the differences in these reported counts, so they should be understood as belonging to different reported analyses rather than treated as interchangeable denominators.
Two secondary outcomes are listed: a patient's global evaluation of allergic rhinitis at the end of treatment and change in the overall Rhinoconjunctivitis Quality-of-life Questionnaire score after treatment. The record lists three outcome measures, but reports zero analyses. Details of the statistical plan, including the planned primary comparison and any adjusted analyses, are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Before assignment: Patients who required excluded medication and those who did not meet a minimum predefined level of combined daytime nasal symptoms score during the run-in period were excluded from randomization.
Overall Study
| Stage | Placebo | Montelukast 10 mg |
|---|---|---|
| STARTED | 990 | 1002 |
| COMPLETED | 906 | 913 |
| NOT COMPLETED | 84 | 89 |
Reasons for not completing this period:
| Reason | Placebo | Montelukast 10 mg |
|---|---|---|
| Adverse Event | 35 | 32 |
| Lack of Efficacy | 12 | 14 |
| Lost to Follow-up | 4 | 3 |
| Protocol Violation | 23 | 25 |
| Withdrawal by Subject | 4 | 10 |
| Other | 6 | 5 |
Analysis population for the primary outcome, as defined in the registry: The primary efficacy analyses were performed using a modified intention-to-treat (MITT) approach. All patients with efficacy measurements, both at baseline and during the treatment period were included.
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 | Placebo | Montelukast 10 mg | Total |
|---|---|---|---|---|
| Participants analysed | 990 | 1002 | 1992 | |
| Age, Continuous | years | 36.6 (SD 13.12) | 36.3 (SD 13.61) | 36.4 (SD 13.36) |
| Sex: Female, Male: Female | Participants | 632 | 644 | 1276 |
| Sex: Female, Male: Male | Participants | 358 | 358 | 716 |
| Daytime nasal symptoms score | Scores on a scale | 2.10 (SD 0.41) | 2.09 (SD 0.40) | 2.10 (SD 0.41) |
| Rhinoconjunctivitis Quality-of-Life Score | Score on a scale | 2.96 (SD 1.10) | 2.94 (SD 1.04) | 2.95 (SD 1.07) |
6. Primary Endpoint
The registry lists the primary outcome as Mean Change From Baseline in Daytime Nasal Symptoms Score Averaged Over the 6-week Treatment Period in Patients With Perennial Allergic Rhinitis, measured over 6 week treatment period (from baseline though the end of week 6).
| Element | Registry entry |
|---|---|
| Result type | Least Squares Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | Score on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is the mean change from baseline in the Daytime Nasal Symptoms score averaged over the six-week treatment period. The score was calculated from daily patient ratings of congestion, rhinorrhea, and sneezing. Each symptom was rated on a four-point scale, with 0 representing the best state and 3 the worst. The three symptom ratings were averaged to form the daytime score.
Change from baseline expresses the average symptom score during treatment relative to the score at the start of treatment. A negative change indicates a lower score during the measured period than at baseline, which corresponds to a lower symptom score on this scale. The reported outcome is a least-squares mean, with a 95% confidence interval, for each treatment arm. The registry record does not describe the model used to obtain those least-squares means.
As a continuous measure, the endpoint retains information about the degree of score change rather than reducing each participant's experience to a yes-or-no response. Averaging daily ratings across the treatment period can represent symptom experience over time; in general, repeated measurements may also reduce the influence of an atypical single day. The registry record does not state why this endpoint was selected or how its clinical importance was defined. The posted results are arm-specific summaries, not a direct estimate of the difference between treatments.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted least-squares mean change was -0.37 for placebo, with a 95% confidence interval from -0.4 to -0.34. For montelukast 10 mg, the mean change was -0.44, with a 95% confidence interval from -0.48 to -0.41. Both arm summaries are below baseline on the score's direction: lower symptom ratings correspond to less severe symptoms. These are descriptive summaries of change within each arm.
The confidence intervals communicate uncertainty around the estimated arm means. In general, a confidence interval is a range of values compatible with the data and the estimation procedure at the stated confidence level. It is not a range containing every participant's change, and it is not a probability statement about a particular fixed true value. The posted intervals are for each arm separately. The registry record does not post a confidence interval for the between-arm contrast, a p-value for that contrast, or an adjusted treatment estimate.
For the clinical question of comparative treatment effects, the important statistical quantity would ordinarily be a direct contrast between the randomized groups, along with its uncertainty. Comparing two arm-specific means informally is not a substitute for that contrast: the uncertainty of a difference depends on the joint comparison and its analysis, not just on reading the two means or their intervals separately. The record's stated lack of estimable values for a two-arm continuous comparison means the posted results do not support reporting that comparison from the available registry entries.
The endpoint population and safety population also differ in the counts reported by arm. The primary efficacy results give 980 for placebo and 1000 for montelukast; the safety results give 990 and 1002 at risk, respectively. The record does not explain the count differences. They should not be combined or interpreted as a single common analysis denominator.
Consequently, the posted endpoint results show that both groups had negative average changes from baseline and give some precision information about each group mean. They do not establish the size or statistical uncertainty of the treatment-versus-placebo difference, nor do they resolve whether any observed contrast is clinically important. Those comparative details are not reported in the registry record.
9. Statistical Methods Explained
The primary outcome is continuous: it is a numerical score formed from symptom ratings. In general, a continuous outcome can be summarized by a mean, which describes the average value in a group. The registry reports least-squares means rather than identifying the estimates simply as raw arithmetic means. Least-squares means are model-based estimates; the model and its covariates are not reported in the registry record, so the exact adjustment behind these estimates cannot be reconstructed from the posted results.
What does change from baseline represent?
A change score compares a participant's measurement during follow-up with that participant's baseline measurement. The trial's endpoint averages the daytime symptom score over the six-week treatment period and reports the mean change from baseline. This expresses the outcome in the original score units. The symptom score's direction matters: its component ratings run from 0, best, to 3, worst. A negative change is therefore a decrease in symptom score, not an increase in symptom severity.
Change scores and follow-up scores answer related but not identical questions. A change score describes movement relative to baseline; a follow-up score describes the level at follow-up. In general, baseline adjustment can account for starting values in a comparison, but the registry record does not explain the model used or say how baseline scores entered it. The posted estimates should therefore be read as reported, without attributing an unreported adjustment strategy to the analysis.
How should the confidence intervals be read?
The 95% confidence intervals accompany the mean change in each arm. In general, confidence intervals convey statistical precision: narrower intervals indicate less uncertainty around the estimated quantity under the assumptions of the method. They do not describe the spread of individual patients' outcomes. The posted intervals are -0.4 to -0.34 for placebo and -0.48 to -0.41 for montelukast 10 mg. These intervals characterize the arm-specific estimates, not the difference between arms. A comparison requires an estimate and uncertainty calculated for that contrast.
In general, a p-value addresses how compatible data are with a specified null hypothesis under a statistical model. It does not measure clinical importance or the probability that a treatment works. No p-value for the primary between-arm comparison is reported in the registry record. The record also does not give the test statistic, model specification, or a numerical estimate of the comparison. No recalculated comparison is reported for this continuous outcome.
Why does the comparison need its own analysis?
Randomization creates a design for comparing assigned groups, but the statistical result still needs to quantify that comparison. Separate group means summarize each arm; they do not directly state the estimated difference or the uncertainty around it. In general, the standard error of a contrast reflects uncertainty from both arms and the analysis structure. It cannot be obtained by treating each arm's interval as if it were itself an interval for the treatment contrast. The registry record flags values as missing or not estimable for a two-arm continuous comparison, so a comparative estimate should not be inferred from the arm summaries alone.
Over-dispersion is a general issue for outcomes such as counts when observed variability exceeds that expected under a simple model. It can make standard errors too small if the analysis assumes less variability than the data contain. That concern is not the central feature of this endpoint, which is a continuous symptom score, and no specific over-dispersion method is reported for this trial. More broadly, model assumptions matter for any estimated mean or contrast, but the registry record does not provide enough detail to assess the fitted model.
What do planning calculations mean?
In general, sample-size planning uses assumptions about a target effect, variability, significance level, allocation, and analysis to illustrate how much information a future study might need. Such an illustration is not an observed result and is not the trial's own design justification unless the record establishes that it was used in planning. The registry record does not report the study's sample-size justification or assumptions. Any planning illustrations associated with the posted results should be read as hypothetical calculations based on stated assumptions, not as observed power or proof that the study could detect a particular effect.
The record does not report an interim-analysis plan, stopping boundaries, or detailed statistical analysis plan. Those omissions mean readers cannot verify from the registry entry which model, covariate set, missing-data method, or multiplicity procedure governed the sponsor's analysis. General statistical concepts can explain what such choices would affect, but they cannot supply the trial-specific methods that are not reported.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists three outcome measures and identifies two secondary outcomes: a patient global evaluation at the end of the six-week treatment period and change in the overall RQLQ score. The primary endpoint is change in daytime nasal symptoms. When several outcomes or repeated comparisons are tested, the chance of at least one apparently notable result can increase. In general, multiplicity procedures can address this by controlling error across a defined family of tests. Whether the trial used such a procedure, which outcomes were grouped together, and whether any hierarchy was prespecified are not reported in the registry record.
The record lists zero analyses. It therefore does not provide posted estimates or inferential results for the secondary outcomes. Their presence as listed outcomes should not be mistaken for evidence that their results were analyzed, reported, or statistically significant. The registry record also does not report a statistical analysis plan, testing sequence, or interim analysis details.
The primary efficacy population is described as modified intention-to-treat and includes patients with efficacy measurements at baseline and during the treatment period. That definition indicates that availability of measurements was part of inclusion in this analysis. The record does not report how many randomized participants lacked measurements, why measurements were unavailable, how missing data were handled, or whether sensitivity analyses assessed the consequences of missingness.
In general, excluding participants without observed outcomes can affect the interpretation if missingness is related to treatment assignment or outcome. That is a methodological consideration, not evidence that bias occurred in this trial. The registry record does not provide enough detail to evaluate the missing-data mechanism or the robustness of the primary estimate to alternative assumptions.
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 |
|---|---|---|---|
| Placebo | 1 | 990 | 0.1% |
| Montelukast 10 mg | 4 | 1002 | 0.4% |
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 |
|---|---|
| Placebo | 0 of 990 |
| Montelukast 10 mg | 0 of 1002 |
Most frequent serious adverse event terms
| Event term | Organ system | Placebo | Montelukast 10 mg |
|---|---|---|---|
| Myocardial Infarction | Cardiac disorders | 1 of 990 | 0 of 1002 |
| Joint Injury | Injury, poisoning and procedural complications | 0 of 990 | 1 of 1002 |
| Dehydration | Metabolism and nutrition disorders | 0 of 990 | 1 of 1002 |
| Anxiety Disorder | Psychiatric disorders | 0 of 990 | 1 of 1002 |
| Asthma | Respiratory, thoracic and mediastinal disorders | 0 of 990 | 1 of 1002 |
Serious events with the highest arm-level rate: myocardial infarction (0.1%), joint injury (0.1%), dehydration (0.1%), anxiety disorder (0.1%), asthma (0.1%).
The serious adverse event summaries report 1 event among 990 participants at risk in the placebo group and 4 among 1002 at risk in the montelukast 10 mg group. These are event counts and their reported at-risk denominators, not estimates of a causal treatment effect. The registry record does not provide an adjusted comparison, confidence interval, or test for these figures. No deaths are reported in the posted adverse-event fields; death counts are not reported in the registry record.
The record reports zero other adverse events among 990 at risk in the placebo group and zero among 1002 at risk in the montelukast group. The registry does not give further detail on the event definitions or ascertainment in the information summarized for these results. The serious-event terms listed at 0.1% each are myocardial infarction, joint injury, dehydration, anxiety disorder, and asthma. The record does not identify an arm alongside these terms in the listed summary, so they should not be assigned to a particular group based on that list.
Safety counts are descriptive. Small event counts can be imprecise, and event counts alone do not show whether a difference is due to treatment, chance, or other factors. The denominators in these summaries differ from those reported for the primary efficacy endpoint; the record does not explain why. These safety results should be read using their own reported at-risk counts and should not be conflated with the primary symptom analysis.
12. What the Result Does, and Does Not, Mean
The primary outcome results describe average change in daytime nasal symptom scores during six weeks of treatment. The reported mean change was -0.37 for placebo and -0.44 for montelukast 10 mg. The score rates congestion, rhinorrhea, and sneezing, with lower component scores representing less severe symptoms. The 95% confidence intervals convey uncertainty around the arm-specific means, not variation across individual patients and not the uncertainty in a treatment contrast.
These summaries do not, on their own, answer whether the average change differed statistically between montelukast and placebo. The registry record does not report a two-arm estimate, its confidence interval, or a p-value. It also does not report a threshold defining a clinically important change. As a result, the size and precision of the comparative effect, and its clinical importance, cannot be determined from the posted primary results alone.
Nor do the arm means show what happened to each individual participant. An average can coexist with a range of individual responses, but the record does not post the distribution of individual changes. A mean change is not a guarantee that all participants experienced the same direction or degree of change.
The reported safety counts offer a separate descriptive view of serious and other adverse events. Without comparative uncertainty estimates and fuller event details, they do not establish whether treatment caused a difference in risk. The secondary outcomes are listed, but their analyses are not posted in the registry record.
In general, a clinical trial's interpretation depends on its comparative estimates, uncertainty, outcome relevance, and analysis choices. Here, the registry entry gives useful information about the intervention, symptom endpoint, arm-specific changes, and some safety counts, while leaving important comparative and methodological information unreported. The record should therefore be read as a limited account of the trial results, not as a complete basis for claims about comparative benefit or harm.
13. Why This Trial Matters Statistically
This trial illustrates an important distinction in clinical-trial reporting: an outcome can be summarized separately within each randomized group without a corresponding estimate of the contrast between groups. The primary question concerns montelukast compared with placebo, but the registry posts an arm-specific least-squares mean and confidence interval for each group. A direct contrast would make the comparative question explicit and show its uncertainty.
The study also illustrates why analysis populations and denominators need careful attention. The primary efficacy results use one set of reported counts, while the safety summaries use different at-risk counts. Both can be appropriate for their respective analyses, but the registry record does not explain how those populations were formed or why their counts differ. Readers should not assume that one denominator applies to every outcome.
Outcome construction matters as well. The primary measure combines daily ratings of three nasal symptoms and averages them over a defined treatment period. That definition clarifies what the score represents and its direction, while still leaving open questions about model specification, missing observations, and clinical importance.
Finally, the entry lists secondary outcomes but does not report their analyses, and it gives no account of multiplicity control or the detailed analysis plan. These gaps show why registration information, outcome definitions, and complete results all contribute different pieces of evidence. Statistical interpretation depends not just on the numerical means, but also on what was compared, how uncertainty was quantified, and how the analysis population was defined.
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 primary limitation for interpreting comparative efficacy is that a two-arm estimate is not reported for the continuous endpoint. The posted least-squares means and confidence intervals describe each arm separately. Without a between-arm estimate and its uncertainty, the magnitude and precision of the treatment contrast cannot be read directly from the registry results.
The record does not report the model specification behind the least-squares means, the covariates used, or the statistical test for the primary comparison. It also does not provide a detailed analysis plan, sample-size justification, or interim-analysis information. The basis for the modified intention-to-treat population is described in broad terms, but the handling of missing measurements and the extent of missingness are not reported.
There is a count difference between the efficacy summaries and safety summaries, with no explanation in the registry record. This limits the ability to understand exactly how the analyzed groups were formed across outcomes. The registry lists secondary outcomes but no analyses, so those outcomes do not add posted results for assessing the study's findings. The record also does not state a threshold for clinical importance of the symptom-score change.
Safety information is limited to the posted event counts and listed serious-event terms. Comparative uncertainty estimates and further details about ascertainment are not reported in the registry record. These limitations concern what the record reports; they do not establish that analyses or documentation were absent outside the registry.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: The Clinical Effects of Montelukast in Patients With Perennial Allergic Rhinitis (0476-265) — NCT00092118.
- Registry record last updated 2022-02-03; status last verified 2022-02.
- Results first posted 2010-07-23.
- 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
NCT00092118 is a completed phase 3 randomized, double-blind, parallel-group, placebo-controlled study sponsored by Organon and Co. The record reports enrollment of 1992 and a study period beginning in 2003-10, with primary completion in 2004-05. The population was patients with perennial allergic rhinitis, and the treatment period for the primary endpoint was six weeks.
The primary outcome was mean change from baseline in the daytime nasal symptoms score averaged over treatment. The registry reports arm-specific least-squares means and 95% confidence intervals, but no estimable two-arm continuous comparison. It lists two secondary outcomes without posted analyses. The primary efficacy population was modified intention-to-treat, defined by having efficacy measurements at baseline and during treatment.
Serious adverse events were reported as counts with at-risk denominators, and deaths were not reported in the registry record. Details of the primary comparison, missing-data handling, multiplicity procedures, and full statistical analysis plan are not reported in the registry record.