A Study to Evaluate SU-VEID™ for Improving Peripheral Venous Access Success in Children: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study to Evaluate SU-VEID™ for Improving Peripheral Venous Access Success in Children (NCT05204082), a randomized na study. The primary outcome is Percentage of Participants With IV Access at First Attempt.

2. Clinical Question

The clinical question concerns whether using the SU-VEID device alongside vein visualization technology changes the chance of obtaining peripheral IV access on the first attempt, compared with standard IV insertion. The registry describes a randomized, parallel-group study in pediatric patients in surgical pre-op who required an IV catheter for surgery. It reports first-attempt access percentages and a between-arm risk difference, but does not report participant characteristics or the detailed procedure used to assess eligibility.

The record describes an evaluation of a procedural device and an immediate access outcome. It does not report whether the primary comparison was adjusted for participant or procedural characteristics, or whether any additional outcomes were planned outside the registered outcome measure. The result therefore addresses the recorded first-attempt endpoint, rather than broader questions about later access attempts, patient experience, or subsequent clinical outcomes.

3. Trial Design

The study is registered as randomized, with a parallel-group model and no masking. The two registered groups are Standard IV Insertion and SU-VEID Assisted IV Insertion. Their descriptions place the study in pediatric surgical pre-op, where patients required an IV catheter for surgery. The intervention is a single-use vein entry indicator device. The registry identifies Mayo Clinic as sponsor.

The enrollment figure is 169. The posted outcome data list 84 participants in the standard insertion group and 85 in the SU-VEID-assisted group. The registry record does not explain whether these are the numbers randomized, treated, assessed for the endpoint, or included in an analysis population. It does not report the method used to generate the random sequence, how allocation was concealed, or whether any restrictions were used in randomization. These design details cannot be inferred from the randomized designation alone.

The record lists phase as NA. The study start date is 2022-03-28, and the primary completion date is 2022-07-21. Its current status is TERMINATED. The reason for termination and its timing relative to the original plan are not reported in the registry record. No protocol rationale or original sample-size justification is reported there.

No masking was used, according to the registered design. The record does not describe who knew each participant’s assigned procedure or whether outcome assessment was conducted by someone separate from the person performing the insertion. It also does not report the clinical setting beyond surgical pre-op or describe operator training, experience, or consistency of technique. Those omissions limit assessment of how the procedures were delivered and how broadly the findings may apply to other settings.

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

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 Percentage of Participants With IV Access at First Attempt, measured over Baseline.

The primary endpoint is the percentage of participants with IV access at the first attempt. It measures whether an insertion resulted in access on that initial attempt, expressed as a proportion of participants in each study group. The registry labels the timeframe Baseline and describes the outcome as IV access within the first attempt when SU-VEID is used, compared with the conventional procedure.

A first-attempt endpoint is useful for comparing procedural success at the point of initial insertion. It focuses on a clear event that can be counted for each participant, rather than treating the number of attempts or elapsed time as the outcome. In general, a binary endpoint records whether a specified event occurred or did not occur. Comparing the percentages between randomized groups can describe the difference in the frequency of that event.

The registry does not define the operational criteria for a successful access, explain how first attempts were counted in complicated procedures, or state how missing or indeterminate observations were handled. The record also does not report an outcome-assessment procedure or identify a separate analysis population. Consequently, interpretation is tied to the registered endpoint description and the posted group results; details that could clarify endpoint ascertainment are not reported in the registry record.

7. Results Posted in the Registry

• SU-VEID Assisted IV Insertion: 67.1% (57/85) versus 70.2% (59/84) on control; risk difference -3.2 percentage points (95% CI -17.2 to 10.8), risk ratio 0.95 (0.78–1.17); unadjusted two-proportion z-test p = 0.656.

8. Statistical Interpretation

9. Statistical Methods Explained

The registered design is a randomized parallel-group comparison. In general, randomization is used to make assigned groups comparable, on average, with respect to factors that could affect an outcome. It does not ensure that every relevant characteristic is balanced in a particular study. The record identifies the design as randomized but does not report the random-sequence method, allocation concealment, or any stratification or blocking procedures. Those features cannot be assumed.

What does the endpoint count?

The primary outcome is binary: each participant either had IV access within the first attempt or did not, as defined by the endpoint. A percentage expresses the number of participants with the event relative to the relevant group denominator. The posted percentages are 70.2% for standard insertion and 67.1% for SU-VEID-assisted insertion. The comparison details also report 59 events among 84 participants in the standard group and 57 among 85 in the SU-VEID group. The analysis population and handling of missing endpoint data are not reported, so the listed denominators should be interpreted as the denominators attached to the posted outcome rather than as a confirmed account of every randomized participant.

What does a risk difference describe?

A risk difference compares the event proportions in two groups by subtracting one proportion from the other, with the direction determined by which group is first. The registry reports the SU-VEID-assisted group relative to standard insertion, with an estimated risk difference of -0.032. A negative value means the estimated event proportion is lower in the first-named group under that comparison order. The confidence interval is -0.172 to 0.108. It includes zero, the value corresponding to no difference in the estimated proportions. The interval also extends on both sides of zero, so the data are compatible with differences in either direction under the reported interval procedure.

How do relative measures differ?

A risk ratio compares the event probability in one group with the event probability in the other. The reported risk ratio is 0.955, with a confidence interval from 0.779 to 1.171. A value of one represents equal event probabilities in the two groups; the interval includes that value. An odds ratio compares event odds rather than event probabilities. The reported odds ratio is 0.863, with a confidence interval from 0.45 to 1.653. An odds ratio and a risk ratio are different scales, so they should not be read as interchangeable measures. The record does not state which comparative measure was designated as the primary analysis measure.

What does the p-value tell the reader?

The registry reports an unadjusted p-value of 0.656. In general, a p-value describes how unusual data at least as incompatible with a null hypothesis as the observed data would be, assuming the null hypothesis and a specified statistical model. It does not measure the size or clinical importance of an effect, and it does not establish that the null hypothesis is true. The registry record does not identify the test used to calculate this value, specify a prespecified analysis threshold, or report an adjusted p-value. The planning assumption of a two-sided significance level 0.05 belongs to the separate sample-size illustration and should not be treated as documentation of the trial’s own analysis plan.

Why are confidence intervals useful?

A confidence interval communicates uncertainty around an estimate. In general, it reflects the range of values compatible with the observed data under the method used to construct it. A narrower interval indicates greater precision than a wider interval, all else equal. The intervals for the risk difference, risk ratio, and odds ratio span values on either side of their respective no-difference values. This means the posted estimates do not pin down a single direction of effect. The registry record does not report the interval method or whether the comparative estimates were adjusted.

What can be inferred about the analysis plan?

The registry lists one outcome measure and zero posted analyses. A comparison and its statistics are present, but the record does not provide a full statistical analysis plan, including the model, covariates, analysis population, missing-data approach, or any interim-analysis plan. The registry also does not report the original sample-size justification. Those unreported items should not be filled in from customary practice; they remain unknown from the registry record.

10. Confidence Intervals and Precision

The risk difference estimate is -0.032, and its confidence interval runs from -0.172 to 0.108. The interval includes zero, which corresponds to no difference between groups on the risk-difference scale. It extends into both negative and positive values, so it is consistent with an estimated difference favoring either group. The point estimate alone gives a single summary of the observed comparison, while the interval conveys that the estimate is uncertain.

The registry also reports a risk ratio of 0.955 with a confidence interval from 0.779 to 1.171, and an odds ratio of 0.863 with a confidence interval from 0.45 to 1.653. For these relative measures, one is the no-difference value. Both intervals include one. These intervals are broad enough to encompass different possible magnitudes and directions relative to their respective scales, so the point estimates should not be interpreted as precise estimates of a stable effect.

In general, a confidence interval is not a guarantee that the true effect lies within the interval, nor does it describe the range of outcomes for individual participants. It summarizes statistical uncertainty under the method used to calculate it. The registry record does not report that method, and no adjusted interval is listed. The posted arm percentages are 70.2% and 67.1%; no interval for either arm-specific percentage is reported. The combination of the comparative intervals and the unadjusted p-value of 0.656 supports a cautious reading: the estimated contrast is uncertain, and the registry results do not establish a clear direction of difference.

11. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The sample-size figures are planning illustrations based on the observed effect, not a record of the trial’s original design assumptions. They are expressed as participants per arm for the 80% and 90% power columns; they are not total event counts. The stated assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is set as the stated fraction of the observed effect.

The planning rows consider 100% of the observed effect, 75% of the observed effect, and 50% of the observed effect. Within each row, the 80% power column describes the planned participants per arm under the assumptions for a design intended to have an 80% chance of detecting the specified effect if that effect were the true one and the planning model held. The 90% power column describes the corresponding number for a design intended to have a 90% chance under those same conditions. These percentages describe design operating characteristics, not the probability that a study conclusion is correct.

Smaller effects are harder to distinguish from random variation, so planning for a smaller fraction of the observed effect requires more participants per arm under the same assumptions. The illustrations do not establish what enrollment would have been appropriate for a different effect, outcome definition, analysis method, or allocation plan. The registry record does not report the trial’s original sample-size justification or its original power target. These figures are not observed power.

12. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, p₀ and p₁ are the control and treatment proportions, and p̄ is their average.

Worked calculation for this trial

1. Control proportion p₀ = 0.702; treatment proportion p₁ = 0.671; average p̄ = 0.686.
2. First term: z_1−α/2 × √[2p̄(1−p̄)] = 1.96 × 0.6561 = 1.2859.
3. Second term: z_1−β × √[p₀(1−p₀) + p₁(1−p₁)] = 0.842 × 0.6557 = 0.5519.
4. n = (1.2859 + 0.5519)² / (-0.0318)² = 3,341.3, rounded up to 3,342 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
p0 <- 0.702380952380952                          # control proportion
p1 <- 0.670588235294118                          # treatment proportion
n_per_arm <- function(power, frac = 1) {
  q1 <- p0 + (p1 - p0) * frac               # smaller effect = fraction of the observed difference
  pbar <- (p0 + q1) / 2
  z_b <- qnorm(power)
  ceiling(round((z_a * sqrt(2 * pbar * (1 - pbar)) + z_b * sqrt(p0 * (1 - p0) + q1 * (1 - q1)))^2 / (q1 - p0)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (unrounded n per arm)
cat("power.prop.test:", round(power.prop.test(p1 = p0, p2 = p1, power = 0.80)$n, 1), "\n")

# Simulation: how often does the z-test reject at the 80%-power sample size?
set.seed(5204082)
n    <- n_per_arm(0.80)
reps <- 20000
x0 <- rbinom(reps, n, p0); x1 <- rbinom(reps, n, p1)
ph <- (x0 + x1) / (2 * n)
z  <- ((x1 - x0) / n) / sqrt(ph * (1 - ph) * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(z) > z_a, na.rm = TRUE), reps))

Output from running the code

100% of observed effect: n per arm = 3,342 (80% power), 4,473 (90% power)
 75% of observed effect: n per arm = 5,900 (80% power), 7,898 (90% power)
 50% of observed effect: n per arm = 13,181 (80% power), 17,645 (90% power)
power.prop.test: 3341.3 
Simulated power at n = 3,342 per arm: 0.799 (20000 replicates)

The simulation draws many pairs of event counts at the planned sample size and counts how often the two-proportion z-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

13. Multiplicity, Missing Data and Analysis Populations

The registry lists one primary outcome measure and reports no secondary outcome results. It also records zero analyses. The posted primary comparison includes an unadjusted p-value of 0.656, but the record does not describe a prespecified testing hierarchy, family of hypotheses, or multiplicity adjustment. When several outcomes or comparisons are tested, the chance of at least one apparently unusual result can increase; statistical methods may address that issue by adjusting how evidence is evaluated. That is general context, not a description of a procedure used in this study. With no adjustment method reported, it is not possible to determine whether multiplicity was considered in the trial’s analysis plan.

Missing-data methods are not reported in the registry record. The record does not state whether any endpoint observations were missing, how missing outcomes were handled, or whether participants with missing outcomes were excluded or assigned an outcome under a prespecified rule. The comparison details list group denominators and event counts, but those details alone do not reveal the disposition of all randomized participants or the handling of unavailable measurements.

The analysis population is also not reported. In clinical trials, possible analysis populations can be defined in different ways, such as by randomized assignment or by treatment received. Those approaches can answer different questions. The registry does not say which population was used for the posted estimates, whether the groups were analyzed as randomized, or whether any participants were excluded from the analysis. Accordingly, the reported risk difference and related measures should be understood as the posted comparison, without assigning it an analysis-population label that the record does not provide.

The registry record does not report an interim-analysis plan, stopping boundaries, or an analysis plan for the terminated study. The termination status does not by itself establish that an interim analysis took place or that statistical stopping criteria were used. Further detail on endpoint completeness, analysis populations, and the planned handling of multiple tests is not reported in the registry record.

14. Safety Results

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

Deaths

Other (non-serious) adverse events

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

The adverse-event figures report zero serious adverse events in the Standard IV Insertion group, with 84 at risk, and zero in the SU-VEID Assisted IV Insertion group, with 85 at risk. The record also reports zero other adverse events in each group, with the same respective at-risk counts, and zero deaths in both groups. No serious adverse-event terms are listed.

These are event counts recorded in the registry, not estimates that risk is absent. A zero count means that no events of the listed type were reported for the corresponding group in these posted figures. It does not show that an event could never occur, and it does not describe events that were not collected or reported. General interpretation of safety counts also depends on how events were defined, sought, attributed, and monitored.

The registry record does not report the adverse-event collection period, definitions, severity criteria, attribution procedures, or whether the at-risk denominators include all randomized participants. It also does not provide a narrative of safety monitoring or reasons for termination. The figures should therefore be read narrowly as the posted serious-event, other-event, and death counts, without extrapolating them to broader safety conclusions.

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

The posted results show first-attempt IV access percentages of 70.2% for standard insertion and 67.1% for SU-VEID-assisted insertion. The comparison estimate is a risk difference of -0.032, with a confidence interval from -0.172 to 0.108, and an unadjusted p-value of 0.656. These statistics describe an estimated difference in this randomized comparison, with uncertainty that includes both negative and positive values on the risk-difference scale.

The results do not establish a clear direction or precise magnitude of difference. A point estimate is not the same as a settled effect, and a p-value is not a measure of clinical importance. The confidence interval is useful because it displays uncertainty around the estimated contrast; its span across zero means that the reported data are compatible with differing possibilities under the interval method. The registry record does not provide the interval method or the trial’s prespecified testing threshold.

These findings apply to the registered endpoint in pediatric patients in surgical pre-op requiring an IV catheter for surgery. They do not directly answer questions about other settings, other patient groups, later access attempts, time to access, patient experience, or outcomes not reported in the registry. No secondary results are posted. The registry does not provide participant characteristics, procedural details, or analysis-population information needed to assess how closely the study participants and procedures match other clinical contexts.

The status is TERMINATED, but the reason for termination is not reported in the registry record. The status alone does not explain whether the study ended as planned, whether recruitment or follow-up was affected, or whether any analysis decisions changed. The available information supports describing the observed result and its statistical uncertainty, but not attributing the result or termination to an unreported cause.

In general, a statistical comparison cannot establish that one procedure works or does not work in every situation. It summarizes data collected under a particular study design, endpoint definition, and analysis. Here, the record offers a randomized comparison and posted outcome statistics, while leaving several design and analysis details unreported. The appropriate reading is therefore limited to the displayed first-attempt access result and its uncertainty.

16. Why This Trial Matters Statistically

This trial raises a familiar statistical challenge in procedural research: a clinically straightforward binary endpoint can still yield an uncertain comparison. First-attempt access is expressed as a participant-level percentage, and the risk difference gives an absolute-scale summary of the contrast between randomized groups. The point estimate is easy to state, but its interpretation depends on the uncertainty around it and on how consistently the event was defined and recorded.

The confidence interval for the risk difference runs from -0.172 to 0.108 and includes zero. That span matters because it shows that the estimate does not precisely distinguish a difference in one direction from a difference in the other. The risk-ratio and odds-ratio intervals likewise include their no-difference values. Looking at an estimate without its interval, or treating a p-value as a stand-alone verdict, would leave out important information about precision.

The record also illustrates why transparency about methods matters. It identifies randomization and a parallel design, but does not report sequence generation, allocation concealment, endpoint handling, analysis population, missing-data methods, or a full statistical plan. These details help readers assess whether the posted comparison matches the intended question and how robust it may be to analytical choices. Their absence does not prove that a method was not used; it means the registry record does not document it.

Finally, planning for a future study requires choices about the effect worth detecting and the desired power. The registry’s planning illustration shows how required participants per arm change as the assumed effect becomes smaller, under stated assumptions. That exercise is distinct from the original design justification, which is not reported. Keeping observed results, uncertainty, and planning assumptions separate helps prevent the current estimate from being mistaken for a precise or definitive answer.

17. 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.
• Participant counts were reconstructed from posted percentages and arm sizes, so small rounding differences are possible.

Several details specific to this trial limit how fully the result can be interpreted. The registry describes the setting as pediatric surgical pre-op and the participants as requiring an IV catheter for surgery, but it does not report age ranges, baseline characteristics, or other eligibility criteria. The outcome may therefore be difficult to place in context for subgroups or settings not described in the record.

The procedural descriptions are brief. The record does not explain the standard insertion technique, how SU-VEID was used with vein visualization technology, who performed the insertions, or whether techniques were standardized across operators. Because the endpoint concerns success on the first attempt, differences in operator or assessment procedures could be relevant, but the registry does not provide enough detail to evaluate them.

The study is listed as TERMINATED. The reason for termination, recruitment history, and whether the planned enrollment or follow-up was completed are not reported. Although the record lists an enrollment figure of 169 and outcome denominators of 84 and 85, it does not identify the analysis population or explain participant flow. It is therefore not possible to determine from the registry record whether all randomized participants contributed to the primary outcome analysis.

The record includes the primary outcome and a comparative estimate, but no posted secondary outcomes or analyses. It does not report the statistical test, adjustment methods, missing-data handling, interval-construction method, or original sample-size rationale. The absence of these details prevents a fuller appraisal of analysis choices and their effect on interpretation. No demographic, procedural, or follow-up information beyond the registered endpoint description is available in the registry record.

18. Related Tutorials

19. Related Statistical Calculators

20. Sources

• ClinicalTrials.gov: A Study to Evaluate SU-VEID™ for Improving Peripheral Venous Access Success in Children — NCT05204082.
• Registry record last updated 2024-05-23; status last verified 2024-05.
• Results first posted 2024-05-23.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

21. Record Summary

The registry record describes a randomized, unmasked, parallel-group study sponsored by Mayo Clinic, comparing Standard IV Insertion with SU-VEID Assisted IV Insertion in pediatric patients in surgical pre-op requiring an IV catheter for surgery. The registered primary outcome is the percentage of participants with IV access at the first attempt, with a timeframe recorded as Baseline.

Enrollment is listed as 169. The posted arm data report 70.2% for standard insertion and 67.1% for SU-VEID-assisted insertion. The comparison reports a risk difference of -0.032, a confidence interval from -0.172 to 0.108, and an unadjusted p-value of 0.656. The record lists no secondary outcome results and no analyses.

The study started on 2022-03-28, has a primary completion date of 2022-07-21, and is marked TERMINATED. The reason for termination, the trial’s original design assumptions, and several analysis details are not reported in the registry record. The adverse-event figures list zero serious events, zero other events, and zero deaths in each group.