Efficacy of Macrolide and Glucocorticoid in the Treatment of Chronic Rhinosinusitis After Endoscopic Sinus Surgery: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Efficacy of Macrolide and Glucocorticoid in the Treatment of Chronic Rhinosinusitis After Endoscopic Sinus Surgery (NCT02182492), a randomized na study. The primary outcome is Total Subjective Symptoms Visual Analog Scores (VAS).

2. Clinical Question

The primary outcome combines patient ratings of nasal obstruction, rhinorrhea, loss of sense of smell, facial pain or pressure, and headache. Higher total scores indicate greater reported symptom severity. This makes the measure relevant to patients’ reported experience, while also leaving the outcome dependent on subjective ratings. The record does not specify the exact statistical contrast intended—for example, whether the principal comparison was a difference at a particular follow-up visit, a change from baseline, or a pattern over follow-up. It also does not report how the subtype question was to be assessed analytically.

3. Trial Design

The registry describes a randomized, single-masked, parallel-group study of postoperative treatment after ESS for chronic rhinosinusitis. The two named treatments were fluticasone propionate nasal spray and clarithromycin tablets. The record characterizes the investigation as prospective and randomized and gives a total enrollment of 187 patients who met eligibility criteria. The study status is completed.

The record gives a start date of 2014-01 and a primary completion date of 2015-12. It lists the study phase as NA. The meaning of the single-masked designation is not clarified: who was masked, how masking was maintained, and whether outcome assessors were masked are not reported in the registry record. The randomization sequence method, allocation concealment, and any stratification by chronic rhinosinusitis subtype are also not reported in the registry record.

Symptoms were to be recorded just before ESS and at 1-, 3-, 6- and 12-month follow-up visits. The description says treatment began one week after surgery. Seven patients in the fluticasone propionate group and 8 patients in the clarithromycin group dropped out because of nonadherence. The record does not state whether the listed enrollment represents the number randomized, nor does it give a complete participant flow by arm for each follow-up visit.

The registered primary outcome was total subjective symptoms VAS. Total nasal endoscopic scores were listed as a secondary outcome. The record names three outcome measures but does not provide outcome results or a statistical analysis for them. Further details of the protocol, treatment duration, dose, eligibility criteria, and analysis plan are not reported in the registry record. Although the study objective refers to different subtypes, the record does not provide enough detail to determine how that objective was incorporated into the design or 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.

Before assignment: Patients meeting the Chronic rhinosinusitis (CRS) diagnostic criteria outlined in the European Position Paper on Rhinosinusitis and Nasal polyps (EP3OS) definition were enrolled. Three subtypes CRS included: CRS without nasal polyps (CRSsNP); non-eosinophilic CRS with nasal polyps (Non-Eos CRSwNP); eosinophilic CRS with nasal polyps (Eos CRSwNP).

Overall Study

Analysis population for the primary outcome, as defined in the registry: A total of 187 patients met the study eligibility criteria. Seven patients in fluticasone propionate group and 8 patients in clarithromycin group dropped out because of nonadherence.

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.

6. Primary Endpoint

The registry lists the primary outcome as Total Subjective Symptoms Visual Analog Scores (VAS), measured over Scores will be recorded just before ESS and at 1-, 3-, 6- and 12-month follow-up visit..

The primary endpoint is the total subjective symptoms visual analog score. Patients rated five major symptoms: nasal obstruction, rhinorrhea, loss of sense of smell, facial pain or pressure, and headache. Their ratings were summed to form a total VAS ranging from 0~50, with 0 representing no complaint whatsoever and 10 the worst imaginable complaint for an individual symptom. Higher total scores indicate greater symptom severity.

This endpoint is used to capture patients’ experience of symptoms rather than relying only on an examination-based assessment. Its multiple symptom domains reflect several aspects of chronic rhinosinusitis, while the total score offers a combined measure. The measure is continuous, and the registry specifies that results are to be described using a mean and standard deviation.

Scores were to be recorded just before ESS and at 1-, 3-, 6- and 12-month follow-up visits. The record therefore describes repeated measurements over time, but does not state which visit or summary across visits was designated as the primary treatment comparison. It also does not report the observed scores, changes, uncertainty estimates, or statistical test. Those endpoint results are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the endpoint represent?

The primary outcome is a continuous total symptom score. Patients rate five symptom domains, and the ratings are summed. A larger score means greater reported symptom severity. The registry specifies means and standard deviations as the parameter and measure of dispersion. A mean describes the central level of scores, while a standard deviation describes how spread out individual scores are around that mean. These summaries can help characterize an arm, but a treatment comparison also needs an explicit contrast between arms, with uncertainty and the analysis method stated.

The repeated visits matter because the same outcome is intended to be measured before ESS and during follow-up. A comparison could focus on a single visit, change from baseline, or the course of measurements over time. These approaches answer different questions and can rely on different assumptions. The registry lists the schedule but does not identify a primary visit-specific contrast or repeated-measures model. That analytical detail is not reported in the registry record.

How should group comparisons be read?

In a randomized parallel-group study, the intended comparison is between outcomes in participants assigned to the treatment arms. Randomization is designed to make treatment groups comparable on average with respect to factors known and unknown at assignment. It does not guarantee identical groups, and it does not remove the need to report how assignment was generated, how participants were retained, or how outcomes were analyzed. The randomization method and allocation concealment are not reported in the registry record.

For continuous outcomes, an estimated difference in means is a common way to express a group contrast. Its interpretation depends on the scale direction and the definition of the contrast. A confidence interval conveys the uncertainty around that estimate, subject to the model and data. The registry record contains no mean scores, standard deviations, treatment-effect estimate, confidence interval, or p-value for the primary outcome. No trial-specific group comparison can therefore be interpreted from the registered information.

Why can repeated measurements complicate analysis?

Scores from the same participant over time are generally related; they are not independent observations. A suitable repeated-measures analysis accounts for this within-person relationship rather than treating every visit as unrelated. Such analyses can also make explicit how treatment groups are compared across visits and how incomplete follow-up contributes to the estimate. The exact approach, model assumptions, and handling of missed visits are not reported in the registry record. This is a general statistical consideration, not a statement that a particular model was used in this study.

Subgroup questions add another layer. The stated objective includes different subtypes of chronic rhinosinusitis, but the registry does not describe subtype categories, the number of participants in each category, or a statistical test of whether treatment effects vary by subtype. A difference in results within one subgroup and not another is not, by itself, evidence that the treatment effect differs between subgroups. A formal interaction assessment and careful attention to uncertainty are generally needed. No such analysis is reported in the registry record.

What is over-dispersion, and is it relevant?

Over-dispersion means that observed variability is greater than a statistical model expects. It is especially relevant to count outcomes analyzed with models that assume a particular relationship between the mean and variance. The registered primary endpoint is a continuous symptom score, so over-dispersion is not the central issue identified by the endpoint description. This general concept does not imply that any particular model was used or that over-dispersion was observed in this trial. No distributional diagnostics or model checks are reported in the registry record.

What does the planning illustration mean?

The planning assumptions describe an illustration based on an observed effect, not the trial’s original design justification. They specify a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation; the effect to detect is expressed as a stated fraction of the observed effect. For continuous outcomes, the illustration is expressed as participants per arm for a target power level. These assumptions explain the basis of a planning exercise, but no resulting participant-count values are included in the registry information. The trial’s own sample-size justification is not reported in the registry record.

Such planning illustrations are not observed power and do not establish what the completed study could detect. They also cannot replace the treatment-effect estimate and its uncertainty. In particular, an illustration based on an observed effect is conditional on that effect and the stated assumptions. It does not demonstrate that the original design used those assumptions, and it is not evidence about the primary outcome in the absence of posted results.

What can be concluded from the analysis record?

The registry lists zero analyses and contains no primary-outcome findings. It does not identify a hypothesis test, adjustment for baseline scores, covariate set, confidence-interval method, or model for repeated measures. These omissions prevent a detailed appraisal of the planned or executed statistical analysis. General statistical principles can clarify what those methods would address, but they cannot recover an unreported analysis or result.

10. Multiplicity, Missing Data and Analysis Populations

The primary symptom score was scheduled for measurement before ESS and at 1-, 3-, 6- and 12-month follow-up visits. The registry does not state which time point was the primary comparison, whether the principal question concerned change over time, or whether a combined repeated-measures contrast was planned. It also lists total nasal endoscopic scores as a secondary outcome and describes an objective involving different chronic rhinosinusitis subtypes. Considering several visits, outcomes, or subgroups can create multiplicity: when many statistical questions are tested, the chance of at least one apparently notable result can increase. This is a general concern; the registry record does not report a multiplicity strategy or adjusted results.

The registry states that seven participants in the fluticasone propionate group and 8 in the clarithromycin group dropped out because of nonadherence. It does not report the number with observed primary-outcome data at each visit, any other reasons for missing data, or whether participants were analyzed according to randomized assignment. The analysis population is not reported in the registry record.

Methods for missing scores are also not described. In general, complete-case analysis uses only participants with the required measurements; other approaches may use models or imputation under explicit assumptions. Different approaches can yield different estimates, particularly when missingness is related to treatment or symptoms. No missing-data assumptions, sensitivity analyses, or imputation procedures are reported. The extent to which attrition could affect the treatment comparison therefore cannot be evaluated from the registry record.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry reports serious adverse events for the glucocorticoid group among 93 participants at risk and for the clarithromycin group among 94 participants at risk. The serious adverse event count is 0 for each group. This means the record lists no serious adverse events in either group for the recorded safety information; it does not establish that no events occurred outside what was captured or reported.

For other adverse events, the registry lists 5 affected participants among 93 at risk in the glucocorticoid group and 5 among 94 at risk in the clarithromycin group. The record does not identify the specific non-serious events in these figures. Deaths are not reported in the registry record. The serious-event terms list is empty.

These safety counts should be read as descriptive registry entries, not as a complete comparative safety analysis. The record does not provide event-level detail, follow-up time for safety, severity or relatedness assessments, or statistical comparisons. The counts alone do not establish whether the treatments differ in safety, and they should not be interpreted as evidence that either treatment is safe or unsafe.

12. What the Result Does, and Does Not, Mean

The registry record shows that a randomized comparison was designed to examine postoperative fluticasone propionate nasal spray and clarithromycin tablets in patients with chronic rhinosinusitis after ESS. It identifies a patient-reported symptom measure, explains its symptom domains and direction, and gives the intended schedule of baseline and follow-up measurements. These details clarify what investigators sought to measure.

However, the record does not report the primary endpoint values or a statistical comparison between the groups. It therefore does not show whether average symptom scores differed, how large any difference was, how uncertain an estimate might be, or whether the pattern of scores varied over follow-up. The registry also does not report the planned analysis for the study’s question about chronic rhinosinusitis subtypes.

A completed status does not fill those gaps. Nor do adverse-event counts answer the efficacy question: the registry reports serious and other adverse-event counts, but gives no detailed comparative safety analysis. The absence of reported primary-outcome results is not evidence that the treatments had the same effect, and it is not evidence that one treatment was better. It means the registered information does not permit that judgment.

More generally, statistical interpretation requires both an estimate and its uncertainty, alongside clarity about the outcome, comparison, analysis population, and handling of missing observations. Those elements are not reported for the primary endpoint in this record. The appropriate conclusion is limited: the trial’s intended comparison and outcome are described, but its observed symptom results and inferential findings are not reported in the registry record.

13. Why This Trial Matters Statistically

This trial raises several statistical issues common to clinical studies of postoperative care. First, its primary outcome is patient-reported and measured repeatedly. The total VAS combines ratings across five symptoms, so it is important to distinguish the overall score from individual symptom results and to make clear which visit or time-course contrast addresses the main question. The registry gives the measurement schedule but does not state the primary comparison in sufficient analytical detail.

Second, the stated interest in chronic rhinosinusitis subtypes creates a question about effect variation. Subgroup analyses can be informative when their definitions, rationale, and analysis are specified, but they can also be imprecise. A planned test of whether treatment effects vary across subtypes is different from comparing separate within-subgroup findings. The registry does not report the subtype definitions or analysis plan.

Third, follow-up and missing data matter. The record identifies nonadherence-related dropout in both treatment groups, but does not show the outcome-data completeness at each visit or the method used to address missing measurements. That information is needed to judge whether the analysis reflects the randomized comparison and how attrition may affect precision.

Finally, the record’s completed status sits alongside an absence of posted outcome analyses. This distinction is statistically important: design and measurement information can explain the question, but cannot substitute for estimates, uncertainty intervals, and a transparent analysis. Without those findings, readers cannot assess the magnitude or precision of the treatment comparison.

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 principal limitation of the registry record for statistical interpretation is the absence of primary-outcome results. No arm-specific means or standard deviations, treatment contrast, confidence interval, or p-value is reported. The record also lists zero analyses. As a result, the central efficacy question cannot be evaluated from the registered results.

The intended comparison is not fully specified analytically. Although the outcome was to be measured before ESS and at 1-, 3-, 6- and 12-month follow-up visits, the record does not identify a primary visit-specific contrast or a model for the repeated observations. It does not say whether the analysis was based on endpoint scores, change from baseline, or another summary. The details of the protocol and statistical analysis plan are not reported in the registry record.

The study objective refers to different chronic rhinosinusitis subtypes, but subtype definitions, participant counts by subtype, and subgroup analyses are absent. The single-masked designation is not accompanied by a description of who was masked. The randomization procedure and allocation concealment are also not described. These omissions limit assessment of design implementation and subgroup interpretation.

Missing-data reporting is limited to nonadherence-related dropout: seven patients in the fluticasone propionate group and 8 in the clarithromycin group. Visit-level outcome availability, other reasons for missingness, the analysis population, and methods for handling missing scores are not reported. The record also does not give treatment dose or duration. These limitations do not establish that the study was conducted improperly; they describe what cannot be assessed from the registry record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Efficacy of Macrolide and Glucocorticoid in the Treatment of Chronic Rhinosinusitis After Endoscopic Sinus Surgery — NCT02182492.
• Registry record last updated 2018-09-25; status last verified 2018-09.
• Results first posted 2018-09-25.
• 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.

18. Record Summary

NCT02182492 is a completed, randomized, single-masked, parallel-group study of postoperative fluticasone propionate nasal spray versus clarithromycin tablets for chronic rhinosinusitis after ESS. The record lists enrollment of 187 patients and describes the primary outcome as total subjective symptoms VAS, measured before surgery and at 1-, 3-, 6- and 12-month follow-up visits. Higher scores indicate greater symptom severity.

The registry reports nonadherence-related dropout of seven patients in the fluticasone propionate group and 8 in the clarithromycin group. It lists serious adverse events as 0 in each group and other adverse events affecting 5 participants in each group. Primary-outcome results, statistical analyses, analysis populations, and missing-data methods are not reported in the registry record.