Effects of Bilastine on F1 Simulator Driving Performance in Patients Affected by Allergic Rhinitis and/or Urticaria: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effects of Bilastine on F1 Simulator Driving Performance in Patients Affected by Allergic Rhinitis and/or Urticaria (NCT02576041), a na phase 4 study. The primary outcome is Standard Deviation Lateral Position (SDLP) Evaluated During the F1 Simulator Test.

2. Clinical Question

The registry lists maintenance of constant speed and time to reaction as secondary outcomes, alongside SDLP as the primary outcome. It records 19 enrolled participants, but does not provide outcome results or explain how many participants contributed data to each outcome. The question is therefore about the study’s measurement plan and design, rather than a posted estimate of how SDLP changed between treatment periods. Because the design is single-group and not randomized, the placebo run-in should not be read as a like-for-like control arm. Any difference between observations at different visits could also reflect factors other than treatment; the registry record does not report an analysis that addresses such factors.

3. Trial Design

This completed phase 4 study is registered as a single-group study with allocation listed as NA and masking listed as none. The registry describes a sequence in which participants received placebo during a run-in period and then initiated bilastine treatment. The arm title is “Placebo (run-in); Bilastine.” The available arm description says that a simulator test was performed after the placebo-treatment period and that the bilastine period was initiated afterwards. Each period is described as 7 (+3) days.

The registry reports 19 enrolled participants. The eligible population is described as adult outpatients of either sex with allergic rhinitis and/or chronic urticaria who could complete a preliminary F1-high speed simulator test without signs or symptoms of intolerance. The study status is completed. The listed start and primary completion dates are 2015-10 and 2015-12.

This design differs from a randomized parallel-group trial. It does not assign participants to separate bilastine and placebo groups for a concurrent comparison. Instead, the arm description indicates that placebo preceded active treatment. Such a sequence can make within-participant observations relevant, but the registry record does not report a statistical model, adjustment strategy, or other details showing how observations from the different visits were compared. The study is unmasked, so the registry does not report masking of participants or study personnel.

The registry lists three outcome measures: SDLP as primary, with maintenance of constant speed and time to reaction as secondary outcomes. It records no analyses. It does not report a detailed statistical plan, sample-size justification, participant flow, or reasons for any missing outcome data. The planning illustrations associated with the posted results are not the trial’s own design justification and should not be interpreted as evidence that the study had a particular level of power.

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: Screening was performed in 2 separate sections, at hospital site (H) and at the simulator (S) center. A total of 19 patients were screened and only one discontinued study before starting placebo treatment due to agitation, sickness, transpiration and vomiting at the simulator driving test.

Placebo (run-in)

Bilastine (Active Treatement)

Analysis population for the primary outcome, as defined in the registry: The study included adult outpatient of either sex affected by allergic rhinitis (seasonal or perennial) and/or chronic urticaria (induced or not induced) able to perform a preliminary driving test on F1-high speed simulator without experiencing sign or symptoms of intolerance towards the drive simulation (e.g. nausea, vomiting or dizziness).

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 Standard Deviation Lateral Position (SDLP) Evaluated During the F1 Simulator Test, measured over 7+3 days of active treatment.

The primary endpoint is Standard Deviation Lateral Position (SDLP), measured in meters during the F1 simulator test after 7+3 days of active treatment. The registry describes SDLP as mainly assessing attention capacities. During the simulator drive, vehicle position was monitored and deviation from the central position was registered. SDLP summarizes variation in lateral position, so it is intended to describe weaving and the consistency with which a requested path is maintained.

As a continuous measure, SDLP can represent the magnitude of variation rather than simply classifying a drive as successful or unsuccessful. In general, a larger standard deviation means greater variability in the measured position; it does not by itself identify why that variability occurred. Simulator performance is a behavioral measurement under the study’s driving-test conditions. It should not automatically be treated as a direct measure of real-world driving outcomes or as proof of a particular underlying mental process.

The endpoint is relevant to the stated study aim because attention and reactivity were evaluated through psychophysical simulator performance. However, the registry record does not report the observed mean SDLP, its standard deviation, a confidence interval, or a statistical test. It also does not report how the endpoint was analyzed across the placebo run-in and active-treatment visits. The measure’s definition and timing are available, but the posted registry information does not permit an assessment of the size or precision of an observed change.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

SDLP is a continuous outcome. In general, a continuous endpoint can be described by a mean, which represents the central value of the measurements, and a standard deviation, which describes their spread around that mean. The registry identifies the primary endpoint parameter as a mean and its dispersion as a standard deviation. It does not report the actual SDLP mean or standard deviation, so neither the typical measured value nor the variability among measurements can be evaluated from the registry record.

What would an estimate describe?

For a treatment sequence, an analysis might describe measurements at different visits or estimate a within-participant change. These are general possibilities, not methods reported for this study. The registry record does not specify whether the primary analysis used visit-level means, paired changes, a model, or another approach. It also does not report whether any covariates or repeated-measure structure were incorporated. Without those details and the result itself, the statistical estimand—the quantity the analysis was intended to estimate—cannot be identified beyond the endpoint and timing stated in the record.

In general, a confidence interval gives a range of values compatible with an estimate under the statistical model and its assumptions. Its width conveys precision: a narrower interval indicates more precision than a wider interval, while an interval spanning values in different directions may leave the direction uncertain. A confidence interval is not reported for SDLP in the registry record. No interval can therefore be used to judge the precision of a treatment-period contrast.

How should a p-value be read?

In general, a p-value measures how incompatible observed data are with a specified null hypothesis, assuming the statistical model and its assumptions. It does not give the probability that the null hypothesis is true, the probability that a result occurred by chance, or the magnitude of an effect. The registry record does not report a p-value or a hypothesis test for SDLP. A significance conclusion cannot be drawn from the endpoint description alone.

Because the design is single-group and the arm description places placebo before bilastine, interpreting a visit contrast requires care. General sources of variation can include measurement variability, changes over time, and familiarity with a repeated task. These are general considerations for sequential measurements, not documented findings in this trial. The registry does not describe an analysis designed to separate such influences from a treatment-period difference. Nor does it report a randomized concurrent comparison that could balance those influences between groups.

Why does over-dispersion matter?

In general, over-dispersion means the observed variability is greater than a statistical model expects. If a model assumes less variation than is present, standard errors may be too small and confidence intervals may be too narrow; significance tests can then appear more conclusive than the data warrant. The concept is particularly relevant when an outcome’s distribution is not well represented by the assumed model. SDLP is a continuous measure, but the registry does not report its distribution, diagnostics, or a model, so there is no basis to say whether over-dispersion occurred or affected an analysis.

The registry’s planning assumptions describe an illustrative sample-size exercise: two-sided significance level 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect expressed as a fraction of an observed effect. For continuous outcomes, such calculations are described as participants per arm. These are general planning conventions, not observed findings. They do not establish the sample-size justification used for this trial, which is not reported in the registry record. They also do not provide observed power; power is a design property under specified assumptions, and a calculation based on an observed effect should not be presented as proof that the completed study was adequately powered.

For this study, a two-arm planning illustration does not mirror the registered single-group sequence. The assumptions can help frame hypothetical future planning, but they cannot turn the placebo run-in into a randomized comparator or supply a missing treatment-effect estimate. The observed effect used by the planning exercise is not stated in the registry record. The record also does not report an interim analysis plan, the primary analysis population, or a method for handling missing values.

What can the posted statistics establish?

The available registry entries establish the endpoint definition, unit, timing, population description, and broad design. They do not establish an SDLP result, its precision, or the statistical method used to analyze it. The same limitation applies to the listed secondary outcomes. In general, interpreting a continuous endpoint requires both an estimate and an account of uncertainty, alongside enough methodological detail to understand how that estimate was obtained. Those outcome-level elements are not reported in the registry record.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Bilastine")
n   <- c(18)
m   <- c(-0.041)
sp  <- c(0.047)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Bilastine  18  -0.041  0.047  -0.064  -0.018

11. Multiplicity, Missing Data and Analysis Populations

The registry lists three outcome measures: SDLP as the primary outcome, and maintenance of constant speed and time to reaction as secondary outcomes. Considering several outcomes can raise a multiplicity question: when multiple hypotheses are tested, the chance of at least one apparently unusual result can increase. In general, a statistical plan may specify which outcome is primary and whether any adjustment or testing hierarchy will be used. The registry record does not report a multiplicity adjustment, a hierarchy among secondary outcomes, or the number of statistical tests performed. It records zero analyses, so there are no posted outcome tests to interpret.

The record does not report missing-data counts for the efficacy outcomes, participant flow, or reasons measurements may have been unavailable. It therefore does not indicate whether all enrolled participants completed each simulator assessment or how missing measurements were handled. No imputation method, sensitivity analysis, or complete-case rule is reported. Safety figures list 18 at risk in the combined arm label, while enrollment is 19; the record does not explain the difference, and that safety count should not be treated as an efficacy-analysis denominator.

The registry does not specify an intention-to-treat, per-protocol, or other analysis population for SDLP or the secondary outcomes. It also does not report a prespecified statistical analysis plan. These omissions matter because the set of participants analyzed and the handling of incomplete observations can influence the estimate and its uncertainty. The available information does not permit assessment of those choices.

12. 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 lists 18 participants at risk for serious adverse events in the group labeled “Placebo (run-in); Bilastine,” with zero affected by serious adverse events. It lists 18 at risk for other adverse events, with 18 affected. These are registry counts for the reported group and should be read as safety summaries, not as randomized comparisons between bilastine and placebo.

The group label describes a sequence, so the figures do not separate events during the placebo run-in from events during active treatment. The registry record does not report event timing, severity details for other adverse events, or the specific terms for those events. It lists no top serious-event terms. Deaths are not reported in the registry record. The figures also do not establish that the same number of participants contributed to the primary efficacy outcome.

These counts describe what the registry reports; without a concurrent control group and further event-level detail, they do not estimate a comparative safety effect. The record does not explain why the safety risk count is 18 while enrollment is 19.

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

The registry record establishes that this completed phase 4 study assessed simulator driving performance in adults with allergic rhinitis and/or urticaria. It identifies SDLP as the primary endpoint, measured in meters after 7+3 days of active treatment, and describes the measure as a way to assess attention-related performance and lateral weaving. It also lists maintenance of constant speed and time to reaction as secondary outcomes.

The record does not report the observed SDLP value, a difference between visits, a confidence interval, or a p-value. It therefore does not show the size or precision of a change in the primary outcome. The same absence of posted results applies to the secondary outcomes. A description of the measure and study aim is not itself evidence of an observed effect.

The design also limits what a contrast across visits could mean. The registry describes placebo as a run-in followed by bilastine, with no random allocation and no masking. It is not a concurrent randomized comparison. Even if a numerical change were available, this sequence alone would not distinguish a treatment-period association from other influences on repeated simulator measurements. The registry record does not report analytical methods that would address those issues.

Simulator performance is a measured task under specified test conditions. In general, it should not be equated automatically with performance in every driving setting or with a clinical outcome beyond the endpoint actually measured. The registry provides no basis for extrapolating to real-world driving or making a treatment recommendation.

Thus, the posted registry information is useful for identifying the study question, outcome definitions, sequence, and reported safety counts. It does not support a conclusion about whether bilastine changed SDLP or about the magnitude, certainty, or cause of any change. Those questions require outcome estimates and analysis details that are not reported in the registry record.

14. Why This Trial Matters Statistically

This study is statistically interesting because it applies a continuous behavioral measure to a clinical research question. SDLP captures variability in vehicle position during a simulator task, rather than reducing performance to a simple pass-or-fail category. The registry’s description makes clear what was measured and why the investigators selected it: attention-related performance, weaving, and consistency in keeping a requested path.

The sequence also makes design interpretation central. A placebo run-in followed by active treatment is different from random allocation to concurrent treatment groups. That distinction affects the kind of comparison the data could support and the assumptions needed to interpret a change across visits. The registry lists allocation as NA, masking as none, and the model as single-group, so the design should not be described as a blinded randomized comparison.

The record is also a useful reminder that endpoints and study aims are not outcome results. Although the primary and secondary measures are identified, the registry reports zero analyses and no efficacy estimates. Without an estimate and an account of uncertainty, neither the size nor precision of any difference can be judged. The study’s posted design details can still guide readers in asking what result would be needed and what limitations would matter when interpreting it.

Finally, the planning assumptions need to be kept separate from evidence from the completed study. Sample-size illustrations based on an observed effect are hypothetical planning tools, not observed power and not proof of the trial’s original design rationale. The actual rationale is not reported in the registry record. Keeping design, endpoint, analysis, and result distinct is essential when the registry contains a study description but no posted outcome analyses.

15. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The main limitation for interpretation is the absence of reported efficacy results. The registry provides no SDLP estimate, dispersion value, confidence interval, or test result, and it records zero analyses. It is therefore not possible to assess the direction, magnitude, or precision of the primary outcome, or to compare it with the listed secondary outcomes.

The study is described as single-group, unmasked, and nonrandomized, with placebo run-in followed by bilastine. That sequence does not provide a concurrent randomized placebo comparison. The registry does not report methods for separating a treatment-period change from time, visit sequence, repeated-task familiarity, or other influences. These are general considerations for a sequential design, not claims about what occurred in the study.

The eligibility description requires participants to be able to complete a preliminary simulator test without signs or symptoms of intolerance. The registry does not report how this criterion affected recruitment or whether the results generalize to people unable to complete that test. It also does not provide outcome-specific participant counts, participant flow, or reasons for missing data. Enrollment is reported as 19, while the safety group lists 18 at risk; the reason is not reported in the registry record.

Other limitations are the lack of a reported statistical analysis plan, analysis population, missing-data method, multiplicity approach, or sample-size justification. The record also does not provide event timing for the safety counts. These omissions restrict assessment of both efficacy analyses and the interpretation of safety summaries.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Effects of Bilastine on F1 Simulator Driving Performance in Patients Affected by Allergic Rhinitis and/or Urticaria — NCT02576041.
• Registry record last updated 2017-04-18; status last verified 2017-03.
• Results first posted 2017-01-16.
• 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.

19. Record Summary

This completed phase 4 study, NCT02576041, examined bilastine and F1 simulator performance in adults with allergic rhinitis and/or urticaria. The registry describes placebo run-in followed by bilastine treatment, with each period lasting 7 (+3) days. The design is single-group, allocation is listed as NA, and masking is none. Enrollment is 19.

The primary outcome is SDLP in meters after 7+3 days of active treatment. Maintenance of constant speed and time to reaction are listed as secondary outcomes. The registry records zero analyses and does not report outcome estimates or statistical tests. Safety information lists 18 at risk for serious adverse events, with zero affected, and 18 at risk for other adverse events, with 18 affected. Deaths are not reported in the registry record.

The available record describes the question and design but does not establish an efficacy result or a comparative treatment effect.