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 Herbal Treatment for Perennial Allergic Rhinitis (NCT00456755), a randomized phase 2 study. The primary outcome is Allergic Rhinitis Symptom Score Including Rhinorrhea, Nasal Obstruction, Sneezing, Itchy Nose and Itchy Eyes at Week 4.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00456755 |
| Phase | Phase 2 |
| Condition | Perennial Allergic Rhinitis |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 126 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Chinese University of Hong Kong |
| Results posted | Yes |
2. Clinical Question
Population
People with perennial allergic rhinitis were the intended study population. The registry record does not report detailed eligibility criteria, participant characteristics, or the number who completed treatment.
Intervention
The intervention was Shi-Bi-Lin, described as a classical Chinese herbal formula. The registry record does not give a complete description of its ingredients, dose, or administration schedule.
Comparator
The comparison group received a placebo described as brown-colored starch intended to resemble the Shi-Bi-Lin powder. Further details about how the placebo was administered are not reported in the registry record.
Primary question
The trial set out to compare allergic rhinitis symptom scores at week 4 between the Shi-Bi-Lin and placebo groups. The registry record does not report the group scores or a statistical comparison, so the relative outcome cannot be assessed from the posted results.
The study description also states an interest in changes to immunological parameters in peripheral blood. Those measures are not identified as the primary endpoint in the registry record, and results for them are not reported there. Quality of life, described as the difference between baseline and week 4, is listed as a secondary outcome. Its results are not reported in the registry record either.
The question is therefore clear at the level of the planned comparison, but the record does not provide the outcome data needed to quantify it. The trial enrolled 126 participants overall. That enrollment figure does not establish how many participants contributed data to the week-4 symptom measure or whether all randomized participants were included in its analysis; those details are not reported in the registry record.
3. Trial Design
The registry identifies this as a phase 2, randomized, parallel-group trial comparing Shi-Bi-Lin with placebo for perennial allergic rhinitis. The trial status is completed, and enrollment is listed as 126. Its start is recorded as 2004-03 and primary completion as 2006-04. These record dates do not provide the duration of treatment for an individual participant.
Random allocation is a design method intended to make treatment groups comparable, on average, with respect to both measured and unmeasured characteristics. It does not guarantee identical groups in a particular trial. A parallel-group design assigns participants to a group and compares outcomes between groups rather than having each participant receive both treatments in sequence. The registry does not report the allocation procedure, whether assignment was stratified, or the allocation ratio as part of the design description.
Masking is listed as quadruple. This indicates that the record identifies a fourfold masking approach, but it does not specify which roles were masked or how masking was maintained. The placebo is described as brown-colored starch resembling the SBL powder. That description gives some information about its appearance, but details of its preparation and matching are not reported in the registry record.
The trial is associated with the Chinese University of Hong Kong as sponsor. The registry lists Shi-Bi-Lin as a drug intervention and placebo as the other intervention. The herbal formula description is incomplete in the record, and the regimen, treatment duration, permitted co-interventions, and adherence procedures are not reported in the registry record.
Although enrollment is listed, the record does not give the number assigned to each group for the primary outcome analysis, participant flow, withdrawals, or completion counts. It also does not report a protocol, a sample-size justification, interim analyses, or a detailed statistical analysis plan. The completed status means the trial is recorded as completed; it does not, by itself, establish that all planned analyses or results are available.
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: Confirmed perennial allergic rhinitis and have a positive skin test to house-dust mite, mold antigens and/or animal dander was required. Enter 1-week run-in-period, during which symptom diary was given to each subject for the evaluation of symptoms. Eligible case with total score higher than 4.
Overall Study
| Stage | Shi-Bi-Lin | Placebo |
|---|---|---|
| STARTED | 63 | 63 |
| COMPLETED | 61 | 62 |
| NOT COMPLETED | 2 | 1 |
Reasons for not completing this period:
| Reason | Shi-Bi-Lin | Placebo |
|---|---|---|
| Lost to Follow-up | 2 | 1 |
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 | Shi-Bi-Lin | Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 63 | 63 | 126 | |
| Age Continuous: Age | Year | 41.19 (SD 12.38) | 36.02 (SD 11.14) | 38.60 (SD 12.01) |
| Sex: Female, Male: Female | Participants | 40 | 43 | 83 |
| Sex: Female, Male: Male | Participants | 23 | 20 | 43 |
| Region of Enrollment: Hong Kong | participants | 63 | 63 | 126 |
6. Primary Endpoint
The registry lists the primary outcome as Allergic Rhinitis Symptom Score Including Rhinorrhea, Nasal Obstruction, Sneezing, Itchy Nose and Itchy Eyes at Week 4, measured over 4 week.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | Unit Score |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is titled as an allergic rhinitis symptom score at week 4, including rhinorrhea, nasal obstruction, sneezing, itchy nose, and itchy eyes. It is described as a mean measured in unit scores, with standard deviation as the dispersion measure. A daily diary was used, and participants were instructed to grade symptoms retrospectively each day before bedtime.
The description says that the diary covered general well-being, nasal symptoms, and non-nasal symptoms. The listed nasal symptoms were nasal blockage, rhinorrhea, nose itching, and sneezing; the non-nasal list included itchy and tearing eyes, eye redness, and itching of the ears or palate. The severity scale ranged from no symptoms at 0, through mild at 1 and moderate at 2, to severe at 3. The registry title and diary description do not fully specify how individual symptom ratings were combined into the endpoint score or how diary entries were summarized for the week-4 value. Those scoring details are not reported in the registry record.
Symptom scores are used to represent the reported burden of the condition in a form that can be compared between randomized groups. A mean can describe the group’s average score, while a standard deviation describes how spread out participant scores are around that average. These summaries do not show the full distribution or the experience of every participant. The record gives the measurement description but not the arm-level means, standard deviations, sample sizes contributing to the endpoint, or a between-group estimate. Consequently, the magnitude and precision of the week-4 comparison cannot be read from the posted results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive limitation is that the registry record does not report the primary outcome values or a treatment comparison. It identifies a week-4 symptom score as the primary endpoint and describes the intended comparison of Shi-Bi-Lin with placebo, but it gives no group means, standard deviations, estimated difference, confidence interval, or p-value. The direction, size, and statistical uncertainty of the primary result are therefore not assessable from this record.
The registry lists 126 participants enrolled. Enrollment alone does not show how many participants were randomized, how many had week-4 measurements, or how many were included in an analysis. Those figures and an account of missing observations are not reported in the registry record. Without endpoint-specific participant counts, even a reported group mean would need to be interpreted in light of who contributed data; those outcome summaries are absent as well.
The entry states that the primary outcome has several categories or time points and was not reduced to one comparison. It lists 0 analyses. This means there is no single primary comparison presented in the posted results for interpretation. It does not establish why no comparison is available or whether analyses were conducted outside the registry record.
The registry does list quality of life as a secondary outcome, defined as a difference between baseline and week 4. Its numerical results are not reported in the registry record. The study summary also mentions a hypothesis about immunological parameters in peripheral blood, but no corresponding results are given. Neither the secondary outcome listing nor the hypothesis supplies evidence about observed changes.
For safety, the record lists 0 serious adverse events among 63 at risk in the Shi-Bi-Lin group and 0 among 63 at risk in the placebo group. It also lists 0 other adverse events among 63 at risk in each group. These are the counts entered in the registry, not proof that no event occurred beyond the recorded data. The death counts are not reported in the registry record.
Statistical significance and clinical importance are separate questions. In general, a p-value addresses how compatible data are with a specified statistical model and null hypothesis; it does not quantify the size or practical importance of an effect. A confidence interval expresses the uncertainty around an estimate under the analysis assumptions. Neither can be evaluated for the primary comparison because no estimate or uncertainty measure is reported. No conclusion about the symptom outcome’s direction or magnitude is warranted from the record alone.
9. Statistical Methods Explained
The registry describes a randomized, parallel-group comparison, but does not provide the analysis method used for the primary outcome. The methods below explain general statistical concepts relevant to interpreting a continuous symptom score; they should not be read as a description of the trial’s actual analysis. The statistical plan and analysis details are not reported in the registry record.
What does a mean symptom score describe?
General: A mean is an average that combines the values observed among participants contributing data. It can give a concise description of the group’s symptom score, but it does not describe how scores are distributed or whether participants’ experiences are similar. The standard deviation gives a sense of the spread of values around the mean. A large spread indicates that participant scores vary more; a small spread indicates that they are more clustered. These summaries are most informative when the endpoint is defined consistently and the number and characteristics of participants with measured outcomes are known.
For this trial, the registry identifies a mean and standard deviation but does not report their values. It also does not fully specify how the daily ratings across symptoms and days were combined to form the week-4 endpoint. Without that scoring rule and the results, no group-level mean or between-group difference can be interpreted.
Why compare randomized groups?
General: Random allocation is designed to reduce systematic differences between treatment groups at the point of assignment. An outcome comparison between groups can then estimate the effect associated with assignment, subject to the design, implementation, follow-up, and analysis. Randomization does not prevent chance imbalances, loss to follow-up, measurement problems, or other sources of bias after assignment. The interpretation also depends on whether the analysis follows the intended comparison and how missing observations are handled.
The registry labels the allocation randomized and the trial parallel, but it does not report the allocation sequence method, concealment procedures, group counts for the primary analysis, or a defined analysis population. It therefore does not support a more specific account of the analysis strategy.
What would an effect estimate and confidence interval add?
General: An effect estimate describes the observed contrast between groups on a specified scale. For a continuous endpoint, the contrast might be expressed in the endpoint’s units, but the registry record does not report which contrast or model was used. A confidence interval describes a range of values compatible with the observed estimate under the method’s assumptions. Its width conveys precision: a wider interval reflects less precision than a narrower one. It does not guarantee that the true effect lies within the interval, and it does not address biases that the analysis has not captured.
No effect estimate or confidence interval for the primary outcome is reported in the registry record. Thus neither the direction nor the precision of an observed group difference can be assessed. A p-value is also not reported. General: a p-value is not a measure of effect size and cannot substitute for an estimate with an uncertainty interval. In the absence of these results, a statistical significance judgment cannot be made.
How should the planning assumptions be read?
General: Sample-size planning asks how many observations may be needed to detect a chosen effect under specified assumptions. It is a design exercise, not an observed trial outcome. The registry’s planning description refers to a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the target effect expressed as a fraction of the observed effect. It also distinguishes participant counts per arm for ordinary outcomes from total event counts for time-to-event calculations. These are planning assumptions described by the record, not evidence that the trial had a particular achieved power or that any target was met.
No numerical planning results are reported in the registry record. In particular, the record does not supply a set of participant-per-arm estimates to interpret. Such illustrations, when available, are not observed power and cannot establish whether the trial was adequately designed. The trial’s own sample-size justification is not reported in the registry record.
Why does over-dispersion matter in general?
General: Over-dispersion occurs when observed variability is greater than expected under a statistical model. If a model assumes less variability than is present, standard errors can be too small and confidence intervals too narrow, making results appear more precise than they are. Methods that accommodate extra variability can change uncertainty estimates. The registry does not report that over-dispersion was assessed or that a model requiring such an adjustment was used. The endpoint is described through means and standard deviations, but no analysis model or distributional assessment is reported.
General: Measurement scale, endpoint construction, missing data, and analysis choices all affect how estimates should be read. These are not interchangeable technical details: they determine what population and outcome an estimate represents. For this trial, the registry’s outcome description gives the symptom domains and rating scale, but does not state the final score construction, the handling of missing diary entries, covariate adjustment, or sensitivity analyses. These details are not reported in the registry record, so no specific statistical procedure should be attributed to the trial.
10. Multiplicity, Missing Data and Analysis Populations
The registry’s primary outcome entry is not reduced to a single comparison because it has several categories or time points. This leaves no single primary estimate to interpret in the posted results. The record does not explain how the categories or time points relate to one another, which comparison was intended to be primary for inference, or whether any adjustment for multiple comparisons was planned. A multiplicity strategy is not reported in the registry record.
General: When several outcomes, time points, or subgroup comparisons are examined, the chance of at least one apparently unusual result can increase if each is assessed separately. Procedures for controlling or describing this issue depend on the analysis plan and scientific question. The presence of several measures does not by itself show that an adjustment was required or used. Here, no adjustment method or hierarchy of tests is reported, so the statistical handling of multiplicity cannot be assessed.
The registry lists 0 analyses. It does not report whether this reflects analyses not entered into the registry, incomplete results reporting, or another reason. Quality of life is listed as a secondary outcome measured as a difference between baseline and week 4, but its results are absent. The study summary also mentions immunological parameters, without reporting analysis details or results for them.
The record does not give participant flow, the number with observed week-4 data, reasons for missing measurements, or the method for handling missing data. It also does not define an intention-to-treat, per-protocol, or other analysis population. These omissions matter because the analyzed participants may not represent everyone randomized, and missingness can affect both the estimated group difference and its uncertainty. General: methods that handle missing data rely on assumptions about why measurements are absent; conclusions can depend on whether those assumptions are plausible. No missing-data assumptions or sensitivity analyses are reported in the registry record.
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 |
|---|---|---|---|
| Shi-Bi-Lin | 0 | 63 | 0.0% |
| Placebo | 0 | 63 | 0.0% |
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 |
|---|---|
| Shi-Bi-Lin | 0 of 63 |
| Placebo | 0 of 63 |
The adverse-event entry lists 0 serious adverse events among 63 participants at risk in the Shi-Bi-Lin group and 0 among 63 at risk in the placebo group. It also lists 0 other adverse events among 63 at risk in each group. No serious adverse event terms are listed. These are the registry’s recorded counts for the categories shown.
Counts of 0 in a registry entry do not establish that no adverse event occurred in every participant or that all events were collected and reported. The record does not give event definitions, the observation period for safety, severity criteria, relatedness assessments, or a description of adverse-event ascertainment. The death counts are not reported in the registry record; a missing death count should not be read as a count of 0.
General: Safety counts are most interpretable when the period of observation, completeness of reporting, event definitions, and number of participants assessed are clear. A count alone does not describe the range or timing of events. The registry presents no additional detail with which to characterize safety outcomes or compare the groups beyond the listed counts. The figures therefore describe what is entered in the record, without supporting broader conclusions about safety.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a phase 2 randomized, parallel-group trial compared Shi-Bi-Lin with placebo for perennial allergic rhinitis, with 126 participants enrolled. It identifies a week-4 symptom score as the primary endpoint and describes the daily diary and severity scale. It also records quality of life as a secondary outcome and includes adverse-event counts for each group.
It does not report the numerical primary outcome results, a between-group estimate, an uncertainty interval, or a p-value. The direction and magnitude of any difference are therefore unknown from the posted results. The quality-of-life result and the immunological findings mentioned in the study summary are also not reported in the registry record. The absence of these data is not evidence that the groups had the same outcomes, and it is not evidence that one group had better outcomes.
General: A trial’s result is interpreted by considering the size of the estimated difference, its precision, the outcome definition, missing data, and the design and analysis. Statistical significance alone would not establish whether a difference matters to participants. Conversely, an imprecise estimate might be compatible with a range of effects. In this record, there is no reported primary estimate or interval to evaluate, so those questions remain unanswered.
The safety entry records 0 serious adverse events and 0 other adverse events in each group, among 63 at risk per group. The record does not give enough information about observation and reporting to treat those counts as a complete account of all possible harms. Death counts are not reported in the registry record.
The trial’s completed status, enrollment, and design description are not substitutes for outcome results. They provide context for the study question, but do not establish a treatment effect, its precision, or the completeness of follow-up. Any conclusion about efficacy or safety would go beyond what the posted results document.
13. Why This Trial Matters Statistically
This record illustrates an important distinction between a registered study design and an interpretable result. The study question and key design features are identifiable: randomized assignment, parallel groups, quadruple masking, Shi-Bi-Lin versus placebo, and a symptom endpoint at week 4. Yet the primary outcome values and comparison are not reported. Without an estimate and its uncertainty, the statistical question the trial set out to address cannot be answered from the registry record.
It also highlights why endpoint specification matters. The primary outcome title names a set of symptoms, while the diary description includes additional nasal and non-nasal symptoms and general well-being. The scale is described, but the record does not state how diary ratings were aggregated into the score. A clear definition of the analyzed endpoint is necessary to know what a numerical result would represent and to reproduce or interpret the comparison.
The entry further shows the limits of enrollment and safety counts as stand-alone evidence. An enrollment total does not identify the number contributing endpoint data, and recorded zero event counts do not describe ascertainment or follow-up. Participant flow, missingness, and analysis populations are not reported. Those details help readers judge whether the estimate represents the intended randomized comparison and how robust it may be.
General: Transparent outcome reporting allows readers to distinguish the planned question from the observed estimate and assess its precision. This record makes the planned symptom comparison recognizable but does not provide the numerical outcome needed for that assessment. The statistical lesson is not a conclusion about the herbal formula; it is that design details alone cannot establish an outcome, and an unavailable estimate cannot be replaced by interpretation of the study hypothesis or enrollment figure.
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.
Several trial-specific details needed to interpret the primary endpoint are not reported in the registry record. The symptom score is described through symptom domains and a daily severity scale, but the record does not explain the exact construction of the week-4 score, how daily ratings were combined, or how incomplete diary entries were treated. This limits the ability to determine precisely what a reported mean would summarize.
The registry does not report primary outcome means, standard deviations, a between-group comparison, or the number of participants contributing data. It also does not provide participant flow, withdrawals, reasons for missing measurements, or the analysis population. As a result, the extent of follow-up and the potential influence of missing observations cannot be assessed.
Although masking is labeled quadruple, the roles masked and the procedures used to maintain masking are not described. The intervention description is incomplete, and dosing and treatment duration are not reported in the registry record. Detailed eligibility criteria and participant characteristics are also absent, limiting assessment of who the findings would represent even if the outcome results were available.
The registry does not provide a detailed statistical plan, multiplicity strategy, interim analysis information, or a sample-size justification. It lists 0 analyses and indicates that the primary outcome has several categories or time points rather than one reduced comparison. The reason that no single comparison is presented is not reported in the registry record.
Safety reporting is limited to the listed counts. Event definitions, ascertainment period, completeness, and death counts are not reported. These limitations concern what can be learned from the registry record; they should not be mistaken for proof that the underlying trial lacked these procedures or analyses.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Herbal Treatment for Perennial Allergic Rhinitis — NCT00456755.
- Registry record last updated 2010-01-06; status last verified 2009-11.
- Results first posted 2010-01-06.
- 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 phase 2 randomized, parallel-group, quadruple-masked trial of Shi-Bi-Lin versus placebo for perennial allergic rhinitis. Enrollment is listed as 126, with a start date of 2004-03 and primary completion date of 2006-04.
The primary endpoint is a week-4 allergic rhinitis symptom score based on a daily diary and a severity scale from 0 to 3. Quality of life, defined as a difference between baseline and week 4, is listed as a secondary outcome. Numerical outcome results and a primary treatment comparison are not reported in the registry record; it lists 0 analyses.
The adverse-event entry lists 0 serious and 0 other events among 63 at risk in each group. Death counts are not reported in the registry record. Details of the analysis population, missing data, endpoint scoring, and statistical plan are also not reported.