The Cutting Efficiency of Hybrid Tips in Different Grades of Cataract: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Cutting Efficiency of Hybrid Tips in Different Grades of Cataract (NCT05495555), a registered phase not stated study. The primary outcome is Phaco Time.

2. Clinical Question

3. Trial Design

This is a completed clinical study registered as NCT05495555, with the title “The Cutting Efficiency of Hybrid Tips in Different Grades of Cataract.” The registry record lists Cataract as the condition and the Cataract and Laser Institute of Southern Oregon as the sponsor. Enrollment is listed as 51. The study start date is 2022-08-03, and primary completion is listed as 2024-02-07. These dates and the completed status describe the registry record; they do not supply results for the primary endpoint.

The intervention is the INTREPID® Hybrid tip, identified as a device. The arm descriptions distinguish cataract removal with a high IOP setting from cataract removal with a low IOP setting. The registry record does not state the allocation method. In particular, it does not report that allocation was randomized. The record explicitly notes that the arms are not a like-for-like control comparison. Any observed contrast between the settings would therefore need to be interpreted in light of the allocation and other design details, which are not reported in the registry record.

The stated objective is to assess efficiency using phaco time, aspiration time, and fluid use during removal of grade 3 and grade 4 cataracts. The primary endpoint is phaco time on the surgical visit. Central Corneal Thickness Change From Baseline is listed as a secondary outcome. The registry record lists five outcome measures, but does not give the individual results for these measures in the information. It also lists zero analyses. That lack of analysis detail limits assessment of how the outcomes were compared, how uncertainty was quantified, and whether any adjustments were made.

Eligibility criteria, participant characteristics, masking, procedural standardization, and the handling of participants across the two settings are not reported in the registry record. These omissions matter when considering whether a difference in time or resource use can be attributed to the setting rather than to participant or procedural differences. The enrollment figure alone does not establish how many participants contributed data to each outcome or each arm.

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 Phaco Time, measured over Day 0 (surgical visit).

Phaco time is the registry’s primary endpoint. It is specified as a continuous measure summarized by a mean and standard deviation, with units of seconds and a timeframe of Day 0 (surgical visit). In general, phaco time represents time associated with the phacoemulsification part of cataract removal. It is distinct from aspiration time and fluid use, which the stated objective also identifies as measures of efficiency.

Time is useful as an efficiency measure because it gives a quantitative description of how long a defined procedural component takes. A mean describes the average observed value in the analyzed group, while a standard deviation describes the spread of individual observations around that average. Neither measure alone shows the full distribution, and neither establishes that a difference between settings is caused by the setting.

The endpoint’s interpretation depends on consistent measurement and a clear analysis population. The registry record identifies the unit and timeframe but does not provide a more detailed operational definition, measurement procedure, or population description. It also does not report group means, standard deviations, a difference between groups, or a confidence interval. The posted results therefore do not allow readers to judge the observed phaco-time values or their precision.

Phaco time should not be read as a complete measure of every aspect of cataract surgery or patient outcome. It is the named primary measure of procedural efficiency in this study. The additional measures of aspiration time and fluid use address other aspects of the stated objective, while central corneal thickness change is listed as a secondary outcome. The registry record does not provide results that connect these measures to one another.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary endpoint is a continuous outcome, with mean and standard deviation specified as its summary statistics. General explanation: a mean provides a central summary of measured times, and a standard deviation describes how dispersed observations are around that mean. These summaries can help describe each group, but a group comparison ordinarily also needs an estimated contrast and an account of its uncertainty. The registry record does not report those results for phaco time.

A confidence interval is a range of values compatible with the data and the assumptions of the analysis. It helps communicate precision: a narrower interval indicates greater precision than a wider interval. It is not a guarantee that the true value lies in the interval, nor does it resolve problems in study design or measurement. No confidence interval for phaco time is reported in the registry record, so precision cannot be evaluated.

A p-value, when reported, measures how surprising the observed data would be under a specified statistical model and null hypothesis. It does not measure the probability that a hypothesis is true, and it does not describe the size or practical importance of an effect. The registry record does not report a p-value or an inferential analysis for the primary endpoint. Statistical significance therefore cannot be assessed from the available record.

The stated sample-size assumptions describe a planning illustration based on an observed effect, not the trial’s own design. The illustration assumes a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation; its target effect is a stated fraction of the observed effect. The record does not report the observed effect needed to interpret such planning scenarios or a sample-size justification used to design the study. These illustrations are not evidence of observed power. A planning calculation does not show whether the completed study was adequately designed or whether its results are precise.

The record also notes that time-to-event planning tables use total events, while other planning tables use participants per arm. That distinction matters in general because the quantity used in a planning calculation depends on the outcome type. Phaco time is listed as a continuous measure, not a time-to-event endpoint. No resulting planning sample sizes are stated in the registry information, so no such values can be evaluated or repeated.

General explanation: over-dispersion occurs when observed variability is greater than a statistical model assumes. If a model underestimates variability, its standard errors may be too small and its confidence intervals too narrow. For a continuous time outcome, the distribution and variability of individual times can matter to inference. The record specifies standard deviation as the dispersion summary but does not report an outcome distribution, a model, or a check of model assumptions. There is therefore no basis to claim that over-dispersion occurred or that a particular adjustment was used.

The allocation issue is central to interpreting any potential comparison. In a randomized comparison, a suitable random process can make groups more comparable on average, subject to chance and implementation. Here, the allocation method is not stated, and the registry record says the arms are not a like-for-like control comparison. General statistical methods cannot repair unreported design information. Adjustment for measured factors can sometimes address observed differences, but it cannot ensure control of unmeasured factors, and no adjusted analysis is reported.

The registry record lists zero analyses. It does not describe an analysis model, covariates, standard-error method, confidence level, or method for handling incomplete measurements. A recalculation from summary statistics, when possible, would be an unadjusted reconstruction and would not replace the sponsor’s own analysis if there were a discrepancy. No such recalculated primary result is reported in the registry record. There is therefore no basis to present an independent estimate as a substitute for a sponsor analysis.

Multiplicity concerns arise when several outcomes or comparisons are examined. Testing multiple hypotheses can raise the chance of finding at least one nominally positive result by chance if no adjustment or prespecified hierarchy is used. General approaches include defining a primary endpoint in advance, controlling a family-wise error rate, or treating secondary outcomes as exploratory. The record names phaco time as primary, lists other efficiency measures in the objective, and lists central corneal thickness change from baseline as a secondary outcome. It does not report a multiplicity strategy, confirmatory hierarchy, or analysis plan.

Missing data can affect both descriptive summaries and comparisons. If values are unavailable, the analyzed observations may differ from those originally enrolled; the impact depends on why data are missing and how missingness relates to outcomes or participant characteristics. Common approaches include analysis of observed data, imputation under stated assumptions, and sensitivity analyses. These approaches rely on assumptions that need to be described. The registry record does not report missingness, exclusions from analyses, imputation, or sensitivity analyses, so no missing-data method can be attributed to this study.

Analysis populations also require definition. A report might specify whether analyses include everyone enrolled, participants assigned to a setting, or only those with measured outcomes, depending on design and estimand. The record gives the enrollment figure but does not describe an analysis population or provide the number contributing data to each endpoint. Without that information, the relationship between enrollment and the analyzed outcome data is not established.

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("High IOP Setting", "Low IOP Setting")
n   <- c(51, 51)
m   <- c(41.6, 41.8)
sp  <- c(10, 10.2)
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  High IOP Setting  51  41.600  10.000  38.787  44.413
CARM  Low IOP Setting  51  41.800  10.200  38.931  44.669

11. Multiplicity, Missing Data and Analysis Populations

The registry record identifies phaco time as the primary outcome and lists central corneal thickness change from baseline as a secondary outcome. The stated objective also names aspiration time and fluid use as efficiency measures, and the record lists five outcome measures. It does not report a prespecified hierarchy among these measures, a multiplicity adjustment, or how findings from secondary outcomes were intended to be interpreted. General statistical practice distinguishes a primary confirmatory question from additional outcomes because examining multiple results can increase the chance of a chance finding.

The record lists zero analyses and does not describe a statistical analysis plan. It does not report whether there were interim analyses, what comparisons were planned, or how any multiple comparisons were handled. Those details are not reported in the registry record, so it is not possible to determine whether multiplicity was addressed or to characterize any reported result as adjusted or unadjusted.

Missing-data information is also absent. The registry record does not state whether any endpoint measurements were missing, how missing measurements were handled, or whether sensitivity analyses were conducted. The listed enrollment does not establish the number of observations available for phaco time or any secondary measure. An outcome analysis can include fewer observations than the enrollment figure, but the actual analysis populations are not reported.

In general, missing-data methods depend on why values are absent and on assumptions about their relationship to observed and unobserved outcomes. Complete-case analysis, imputation, and sensitivity analysis answer different questions and have different assumptions. Without the amount, pattern, and handling of missing data, the reliability of an outcome estimate cannot be evaluated. These are reporting gaps, not evidence that data were missing or that a particular method was used.

12. 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.

Most frequent non-serious adverse event terms

The registry record lists adverse-event figures separately for the high IOP setting and the low IOP setting. For each listed group, serious adverse events are recorded as 0 among 51 at risk, other adverse events as 3 among 51 at risk, and deaths as 0. The record does not give the types of the other adverse events in the information. It also does not list serious adverse-event terms.

These figures should be read as the registry’s reported counts and denominators, not as a comparison demonstrating a safety difference between settings. The allocation method is not stated, and the record cautions that the arms are not a like-for-like control comparison. The listed at-risk figures alone do not establish whether all enrolled participants contributed safety data in the same way or whether participants could be represented across the settings.

Zero recorded serious events or deaths does not establish that risk is absent. It describes the event counts recorded in the registry for the stated groups. The record does not provide event descriptions, timing, severity details for the other events, follow-up information, or a statistical comparison. The safety figures therefore offer limited descriptive information and should not be interpreted as a definitive comparative safety assessment.

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

The registry record establishes that a completed study examined the INTREPID® Hybrid tip in cataract removal under high and low IOP settings. Its stated objective was to assess efficiency through phaco time, aspiration time, and fluid use for grade 3 and grade 4 cataracts. The primary endpoint is mean phaco time, measured in seconds at the surgical visit. These details define the research question, but they do not answer it.

The posted results do not report arm-specific phaco-time means, standard deviations, a comparison estimate, or a confidence interval. Nor do they report numerical results for aspiration time, fluid use, or central corneal thickness change from baseline. Without those outcome estimates, the magnitude, direction, and precision of any differences cannot be assessed. The record therefore does not support a conclusion that one IOP setting is more efficient than the other, or that they are equivalent.

The comparison also has design limitations in the registry information. Allocation is not stated, and the record says the arms are not a like-for-like control comparison. A contrast between settings, if reported, would need to be interpreted with that caveat. The available information does not establish that the groups were comparable or that any observed difference would be caused by the IOP setting.

The safety counts are descriptive: each listed setting has 0 serious adverse events among 51 at risk, 3 other adverse events among 51 at risk, and 0 deaths. They do not by themselves establish comparative safety, particularly without event details, follow-up information, and a suitable analysis.

In general, a completed study can still have limited interpretability when outcome estimates and analysis details are not reported. Completion means the registry status is completed; it is not evidence of a favorable, unfavorable, or conclusive result. The findings needed to assess the primary question are not reported in the registry record.

14. Why This Trial Matters Statistically

This study raises a useful statistical question about how to evaluate procedural efficiency across operating settings. Its stated measures distinguish phaco time, aspiration time, and fluid use rather than reducing efficiency to a single broad impression. A continuous endpoint such as time can be summarized with a mean and standard deviation, but interpretation also depends on the group contrast, its precision, and the process used to form the comparison.

The registry record makes an important design limitation explicit: allocation is not stated, and the arms are not a like-for-like control comparison. This illustrates why group labels alone do not establish a valid causal contrast. In clinical research, the method of allocation and comparability of groups affect what a statistical estimate can mean. A numerical difference, even if reported, would not automatically show that the setting caused that difference.

The case also demonstrates the distinction between study completion and a fully interpretable result. The record lists an enrollment of 51 and a primary endpoint, but no primary outcome estimates or analyses. Without group summaries and uncertainty, readers cannot judge effect size or precision. Without a described analysis plan, readers cannot determine how outcomes, missing observations, and multiple measures were handled.

Finally, planning illustrations based on an observed effect should not be confused with evidence about the completed study’s power. Planning assumptions are useful for illustrating how target effects relate to sample-size requirements, but they do not replace a design justification or outcome analysis. This distinction is especially important when the observed effect and resulting planning values are not reported in the registry record.

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 numerical results for the primary endpoint. The registry record defines phaco time as a mean continuous outcome in seconds at Day 0, but does not provide group summaries or an estimated contrast. The stated efficiency measures of aspiration time and fluid use also lack reported results. Without these values, neither the direction nor the magnitude of a difference can be described.

Important design details are not reported in the registry record. Allocation is not stated, and the record explicitly cautions that the arms are not a like-for-like control comparison. Eligibility criteria, participant characteristics, masking, procedural details, and analysis populations are also not specified in the information. These omissions prevent a detailed assessment of comparability, generalizability, and potential sources of bias.

The registry lists five outcome measures but zero analyses. It does not describe a statistical analysis plan, multiplicity approach, treatment of missing data, or model assumptions. Consequently, it is not possible to determine how the analyses were intended to address multiple outcomes, incomplete observations, or variability in the continuous endpoint. No sample-size justification for the trial is reported; the stated planning assumptions are an illustration based on an observed effect, not the trial’s own design.

Safety reporting is also limited in detail. The registry gives counts for serious events, other events, and deaths in each listed setting, but does not provide event types for the other adverse events or further follow-up information. These counts should not be treated as a definitive comparison between settings.

These limitations concern what the registry record reports. They do not establish that methods were absent from the conduct of the study, that data were missing, or that a particular bias occurred. They do mean that readers cannot verify those aspects from the posted record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: The Cutting Efficiency of Hybrid Tips in Different Grades of Cataract — NCT05495555.
• Registry record last updated 2025-03-11; status last verified 2025-02.
• Results first posted 2025-03-11.
• 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

NCT05495555 is a completed study titled “The Cutting Efficiency of Hybrid Tips in Different Grades of Cataract,” sponsored by the Cataract and Laser Institute of Southern Oregon. The registry lists Cataract as the condition, enrollment of 51, a start date of 2022-08-03, and primary completion on 2024-02-07.

The device intervention is the INTREPID® Hybrid tip. The study describes high and low IOP settings for cataract removal and identifies mean phaco time in seconds at Day 0 as the primary endpoint. Its stated objective also names aspiration time and fluid use. Central corneal thickness change from baseline is listed as a secondary outcome.

The allocation method is not stated, and the registry cautions that the arms are not a like-for-like control comparison. Numerical primary-outcome results, analysis details, and a missing-data approach are not reported in the registry record. Safety entries list 0 serious adverse events, 3 other adverse events, and 0 deaths among 51 at risk in each setting.