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 Effect of Pretreatment With Intravenous Lidocaine for Intravenous Contrast: (NCT05143489), a randomized phase 4 study. The primary outcome is Pain Score at 15 Minutes Post Medication Administration.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05143489 |
| Phase | Phase 4 |
| Condition | Pain |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 3 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Antonios Likourezos |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned children receiving intravenous contrast for CT scans in pediatric emergency medicine. The registry summary describes discomfort during contrast administration as a concern because movement can affect image quality. Specific eligibility criteria, age limits, and participant characteristics are not reported in the registry record.
Intervention
The intervention was preservative-free intravenous lidocaine at 1mg/kg, with a maximum dose of 40mg. The stated question was whether pretreatment could reduce pain or discomfort associated with contrast administration.
Comparator
The comparison group received intravenous normal saline at 1mg/kg, with a maximum dose of 40mg. The trial is described as randomized and quadruple-masked. The registry record does not explain the masking procedures or identify the roles covered by quadruple masking.
Primary question
The primary endpoint was pain score at 15 minutes after medication administration. The clinical question was whether recorded pain scores differed between the lidocaine and saline groups. The registry record does not report an estimable two-arm comparison, so it does not establish the size or precision of any between-group difference.
The study rationale focuses on the discomfort children may experience during intravenous contrast injection. The registry summary notes that movement during imaging may affect study quality and describes procedural sedation as one response to anticipated movement, while also noting concerns about sedation in children with upper-airway pathology. These points explain the motivation for examining pretreatment; they are not evidence that lidocaine changes pain, movement, image quality, sedation use, or safety in this trial.
The record describes the trial as Phase 4, randomized, parallel-group, and quadruple-masked. Its status is terminated. Reasons for termination and details of the planned clinical question beyond the registered outcomes are not reported in the registry record.
3. Trial Design
The registry describes a randomized, parallel-group trial comparing preservative-free lidocaine with saline. The official title calls it double-blinded, while the design fields identify quadruple masking. The record does not explain these labels or specify which trial roles were masked. It also does not report the randomization sequence, allocation concealment procedures, or whether the planned design was carried out as intended.
The planned intervention was intravenous lidocaine at 1mg/kg, up to a maximum dose of 40mg. The placebo group was to receive intravenous normal saline at 1mg/kg, also up to a maximum dose of 40mg. The registry lists pain score at 15 minutes post medication administration as the primary outcome. It also lists pain-score outcomes at 60, 90, and 120 minutes as secondary outcomes. Results for those secondary outcomes are not reported in the registry record.
The study started on 2022-01-03, had a primary completion date of 2024-04-17, and is listed as terminated. The enrollment recorded is 3. Posted arm summaries include 1 participant in the lidocaine group and 2 in the placebo group. This realized enrollment is the information available for understanding the posted results; it does not establish what enrollment was originally intended.
The registry record does not report a target enrollment, sample-size justification, recruitment details, stopping rationale, or a statistical analysis plan. It also does not report whether the stated masking and allocation procedures were maintained. Those gaps prevent a fuller assessment of how the trial was designed and conducted. The posted participant counts and outcome summaries are descriptive and should not be treated as evidence that the planned comparison was adequately completed.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Preservative Free Lidocaine Group | Placebo Group |
|---|---|---|
| STARTED | 1 | 2 |
| COMPLETED | 1 | 2 |
| NOT COMPLETED | 0 | 0 |
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 | Preservative Free Lidocaine Group | Placebo Group | Total |
|---|---|---|---|---|
| Participants analysed | 1 | 2 | 3 | |
| Age, Categorical: <=18 years | Participants | 1 | 2 | 3 |
| Age, Categorical: Between 18 and 65 years | Participants | 0 | 0 | 0 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Female | Participants | 0 | 1 | 1 |
| Sex: Female, Male: Male | Participants | 1 | 1 | 2 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: United States | participants | 1 | 2 | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Pain Score at 15 Minutes Post Medication Administration, measured over 15 minutes.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | score on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is pain score at 15 minutes after medication administration. The registry describes the measurement as a mean on a score scale, with standard deviation as the dispersion measure. The outcome description says that assessment would use a combination of the Baker-Wong FACES pain scale, a 1 to 10 numerical scale for pain, and a 5-point Likert scale for discomfort. The description states that both scales range from no pain to very severe pain, with 5 being moderate pain.
Pain is relevant to the study question because the registry summary identifies discomfort during intravenous contrast administration as a potential source of movement during CT imaging. A score at 15 minutes was the registered primary measure for comparing pain after the study medication. The record does not describe how the different scales were combined, how scores from different instruments were reconciled, or how the endpoint was calculated if one or more components were unavailable. Details about assessor training and the measurement process are also not reported in the registry record.
The posted summaries give a mean of 0 and standard deviation of 0 for each arm, with 1 participant in the lidocaine group and 2 in the placebo group. However, the registry indicates that values are missing or not estimable for a two-arm comparison of this continuous endpoint. Therefore, those summaries do not provide a reported comparative effect or its uncertainty. The endpoint description alone cannot establish that the scales were administered consistently or that the score summaries represent a reliable comparison of the groups.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record reports a terminated trial with enrollment of 3. The posted primary-outcome summaries are a mean score of 0 and standard deviation of 0 in the lidocaine group, based on 1 participant, and a mean score of 0 and standard deviation of 0 in the placebo group, based on 2 participants. The registry does not provide an estimable two-arm comparison for this continuous endpoint. No between-group effect estimate, confidence interval, or analysis result is reported.
These values should be read as limited descriptive entries, not as evidence that the treatments produced the same outcome. A mean and standard deviation from groups with these participant counts give little information about the distribution of scores or the precision of a treatment contrast. The registry’s explicit note that the comparison is not estimable is central: the posted results do not support a statistical conclusion about whether pain scores differed between groups.
General statistical point: a confidence interval describes uncertainty around an estimated effect under the assumptions of the analysis. No confidence interval for the primary comparison is reported in the registry record, so the precision of a possible difference cannot be assessed from a reported interval. The absence of an interval is not evidence that the groups were equivalent. Equivalence or non-inferiority would require a defined margin and an appropriate analysis, neither of which is reported in the registry record.
The record lists pain-score outcomes at 60, 90, and 120 minutes as secondary outcomes, but does not report their results. It also records no analyses. Consequently, the posted information does not show whether pain changed over time, whether treatment groups differed at later assessments, or whether any pattern was consistent across assessment times. The statistical plan for handling repeated measurements is not reported in the registry record.
The safety entries report no serious adverse events, other adverse events, or deaths among the participants listed as at risk in either arm. With enrollment of 3, these counts describe only the participants represented in the registry record. They do not provide a precise estimate of the frequency of uncommon events or establish comparative safety.
Overall, the posted data describe a very small, terminated study and do not yield an interpretable primary treatment comparison. The registry record does not state why the study terminated, whether all randomized participants were included in the outcome summaries, or why the continuous comparison was not estimable. Those reasons should not be inferred from the results. The clinical rationale may be important, but the posted outcome data are insufficient to quantify an effect or its uncertainty.
9. Statistical Methods Explained
What kind of outcome was registered? The primary outcome is continuous: it is described as a mean pain score, with standard deviation used to describe spread. For a continuous outcome, an analysis often compares group means or estimates a difference between them. The registry does not report such an estimable two-arm comparison for this endpoint. It reports arm summaries, but the combination of the available participant counts and the recorded outcome information does not produce a posted comparative analysis.
What does a mean and standard deviation convey? General statistical point: a mean describes the average value in a group, while a standard deviation describes how dispersed individual values are around that average. Neither quantity alone gives a treatment contrast or shows how precisely that contrast is estimated. In this record, the mean and standard deviation are both recorded as 0 in each arm, but the arm sizes are 1 and 2. These summaries cannot establish the range of participant experiences or support a dependable estimate of variability. The registry’s note that the continuous comparison is missing or not estimable should therefore take precedence over treating the matching summaries as evidence of no difference.
Why is an inferential comparison unavailable? General statistical point: an inferential comparison uses the observed data and a stated statistical model to estimate a contrast and its uncertainty. With very few observations, estimates of variability and uncertainty can be unstable or unavailable, especially when the recorded spread is zero. The registry record does not give a comparative estimate, test statistic, p-value, or confidence interval. It also does not explain the specific reason the comparison was not estimable. It would be inappropriate to invent a reason or substitute a calculation for an analysis that the record does not report.
How should masking and randomization be understood? Randomization is intended, in general, to create groups whose differences at baseline are not systematically determined by treatment assignment. Masking is intended, in general, to reduce the influence of knowledge about assignment on care, assessment, or reporting. The registry identifies the study as randomized and quadruple-masked; the official title describes it as double-blinded. The procedures, roles masked, and allocation implementation are not reported in the registry record. The design labels alone cannot confirm how these protections operated in practice.
What do the secondary assessment times add? The record lists pain scores at 60, 90, and 120 minutes after medication administration as secondary outcomes. General statistical point: when the same outcome is assessed repeatedly, observations from the same participant may be related. An analysis can account for that dependence, but the choice of method depends on the design and available data. The registry does not report secondary-outcome results or a method for analyzing repeated scores. No time pattern or treatment-by-time comparison can therefore be interpreted from the posted results.
What does multiplicity mean for this study? General statistical point: evaluating several outcomes or time points can increase the chance of finding an apparently notable result by chance if each is tested separately. A statistical plan may specify which outcome is primary and how secondary comparisons will be interpreted or adjusted. The record identifies a primary outcome and lists secondary outcomes, but does not report a multiplicity strategy or analysis plan. Because no outcome analyses are posted, there are no reported significance findings whose interpretation can be adjusted.
How should planning calculations be read? General statistical point: sample-size planning asks how many participants might be needed under stated assumptions to detect an effect at a chosen significance level and power. Such figures are illustrations of a design scenario, not observed evidence and not a measure of the trial’s achieved power. The planning assumptions described for this record use a two-sided significance level of 0.05, equal allocation, a normal approximation, and an effect defined as a fraction of the observed effect. The registry does not report its own sample-size justification. Planning illustrations do not remedy the absence of an estimable comparison in the posted results.
What analysis details remain unknown? The record does not report the statistical model, handling of missing observations, analysis population, covariate adjustment, or interim analyses. It also does not state whether any planned analysis differed from the analysis ultimately performed. These details matter because analysis choices can affect estimates and uncertainty. Without them, interpretation should remain anchored to the limited descriptive summaries and the registry’s statement that the primary comparison is not estimable.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies pain score at 15 minutes as the primary outcome and lists pain scores at 60, 90, and 120 minutes as secondary outcomes. It reports five outcome measures, but does not provide results for the listed secondary time points. No analysis results are posted. A strategy for handling multiple outcomes or time points is not reported in the registry record, including whether any adjustment was planned or how secondary outcomes were intended to be interpreted.
Missing-data methods and the reasons for unavailable or non-estimable results are not reported in the registry record. The record does not state whether all randomized participants contributed data to the primary endpoint, how incomplete measurements were handled, or whether participants were analyzed according to randomized assignment. The analysis population is also not reported. These omissions make it difficult to determine how the posted arm summaries relate to the planned analysis.
General statistical point: missing-data assumptions matter because an analysis may give different results depending on why observations are absent and how the method handles them. With a small enrolled group, the influence of an individual observation can be substantial. The registry record does not provide enough information to evaluate such assumptions or assess the consequences of missing data.
The record also does not report interim analyses, early-stopping criteria, or an analysis plan. The terminated status alone does not explain why enrollment ended or whether stopping was related to recruitment, logistics, safety, or results. Those details are not reported in the registry record and should not be inferred.
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 |
|---|---|---|---|
| Preservative Free Lidocaine Group | 0 | 1 | 0.0% |
| Placebo Group | 0 | 2 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Preservative Free Lidocaine Group | 0 of 1 |
| Placebo Group | 0 of 2 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Preservative Free Lidocaine Group | 0 of 1 |
| Placebo Group | 0 of 2 |
The registry safety entries list 1 participant at risk in the lidocaine group and 2 in the placebo group. Serious adverse events affected 0 participants in each group; other adverse events also affected 0 participants in each group. Deaths are recorded as 0 in both groups. No serious adverse-event terms are listed.
These counts indicate that the registry reports no events of the listed types among the participants represented in the safety summaries. They do not establish that no events occurred outside the recorded observations, nor do they show that the groups have equivalent safety. The record does not report the duration or completeness of safety follow-up, how adverse events were collected, or the criteria used to classify events.
General statistical point: an event count is most informative when interpreted alongside the number monitored, follow-up, and the way events were ascertained. In a study with enrollment of 3, zero recorded events cannot precisely characterize the chance of rare harms. The small number of participants also limits any meaningful comparison of event frequency between the arms. These safety entries are descriptive and should not be read as proof of safety or as a treatment recommendation.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a randomized, parallel-group trial of intravenous lidocaine versus saline was conducted and is now listed as terminated. The enrolled total is 3, with 1 participant in the lidocaine arm and 2 in the placebo arm. The primary outcome was pain score at 15 minutes after medication administration. The posted arm summaries record a mean of 0 and standard deviation of 0 in each group, but the registry states that a two-arm comparison of the continuous endpoint is missing or not estimable.
That information does not show that lidocaine reduced pain, that it had no effect, or that the treatments were equivalent. No comparative estimate or confidence interval is reported, and the registry does not give an analysis result. The recorded means should not be mistaken for a reliable treatment contrast, particularly given the small arm sizes and the registry’s explicit qualification about estimability.
The results also do not answer whether pain scores differed at 60, 90, or 120 minutes. Those outcomes are listed but their results are not reported in the registry record. Nor do the posted data establish effects on movement during imaging, image quality, diagnostic accuracy, sedation use, or airway-related outcomes; these are discussed in the rationale, but are not reported as analyzed results.
The safety entries show zero reported serious adverse events, other adverse events, and deaths among the participants listed in each arm. These counts are not enough to rule out uncommon harms or establish comparative safety. The record does not explain why the trial was terminated, how missing information was handled, or whether all planned analyses were completed. The appropriate interpretation is therefore limited: the posted registry data are descriptive, and the primary treatment comparison remains unresolved.
13. Why This Trial Matters Statistically
This trial addresses a statistical problem that often arises when a clinically motivated study ends with very limited enrollment: the question may be important, while the observed data remain insufficient for a reliable comparison. Here, the registry lists a pediatric imaging context in which discomfort during contrast injection is a concern. The posted enrollment is 3, and the primary continuous outcome is not reported as an estimable two-arm comparison.
The distinction between an observed summary and an interpretable effect estimate is important. Two arm summaries can appear alike without showing that the underlying treatments are equivalent. A treatment comparison requires information about the contrast and its uncertainty, and the registry does not report either for the primary outcome. Small groups also make it difficult to characterize variability, assess balance, or examine whether results are robust to individual observations.
The record further illustrates why trial status, outcome reporting, and analysis details matter. It is marked terminated, but the reason is not reported in the registry record. Secondary outcomes are named without posted results, and no analyses are recorded. Without an analysis plan or explanation of missing and non-estimable results, readers cannot distinguish among possible explanations for the incomplete evidence.
These limitations are not a verdict on the clinical value of the research question. They define what can be learned from the posted record: it documents the intended comparison and a small set of descriptive observations, but does not provide a precise estimate of the primary treatment effect. Keeping that distinction clear is essential when interpreting small or incomplete clinical trials.
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 is the very small recorded enrollment: 3 participants, divided between groups of 1 and 2. The registry reports no estimable two-arm comparison for the primary continuous endpoint. As a result, the posted summaries do not provide a comparative effect estimate or its uncertainty. The zero means and standard deviations in both arms should not be interpreted as evidence of equal outcomes.
The trial is listed as terminated, but the reason for termination is not reported in the registry record. The record does not state whether termination occurred before planned enrollment, whether recruitment was difficult, or whether other operational or scientific considerations were involved. It is also not reported whether all randomized participants completed the primary assessment or contributed to the safety summaries.
The endpoint description refers to a combination of the Baker-Wong FACES pain scale, a 1 to 10 numerical pain scale, and a 5-point Likert discomfort scale. How those measures were combined into the registered score is not reported. The record also does not report assessor procedures, baseline pain information, or details of the measurement instruments’ administration in this study.
Secondary outcomes are listed at 60, 90, and 120 minutes, but their results are not reported in the registry record. Missing-data handling, analysis population, statistical model, multiplicity strategy, interim analyses, and sample-size justification are likewise not reported. The registry gives no explanation for why the primary comparison is not estimable. Together, these limitations prevent a robust assessment of treatment effect, precision, outcome trajectory, and the generalizability of the findings.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: The Effect of Pretreatment With Intravenous Lidocaine for Intravenous Contrast: — NCT05143489.
- Registry record last updated 2025-05-18; status last verified 2025-05.
- Results first posted 2025-05-18.
- 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 Phase 4, randomized, parallel-group, quadruple-masked trial comparing preservative-free intravenous lidocaine with saline before intravenous contrast administration. The lidocaine regimen was 1mg/kg, up to 40mg; the saline regimen was also 1mg/kg, up to 40mg. The primary outcome was pain score at 15 minutes after medication administration, with additional pain-score outcomes listed at 60, 90, and 120 minutes.
The study started on 2022-01-03, has a primary completion date of 2024-04-17, and is listed as terminated. Enrollment was 3, with 1 participant in the lidocaine group and 2 in the placebo group. The arm summaries report a mean of 0 and standard deviation of 0 in each group, while the registry states that the continuous two-arm comparison is not estimable. No analyses are recorded, and results for the secondary outcomes are not reported in the registry record. The listed safety counts show no reported serious adverse events, other adverse events, or deaths in either group.