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 Complete Lesion Assessment With ffR and IVUS TechnologY (NCT01941030), a randomized na study. The primary outcome is Percentage of Calcium Removal Out of Lumen Gain as Assessed by IVUS.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01941030 |
| Phase | NA |
| Condition | Peripheral Artery Disease, Critical Limb Ischemia |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 51 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Abbott Medical Devices |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned patients with critical limb ischemia, a condition listed alongside peripheral artery disease. The registry describes the study as a pilot intended to identify clinically appropriate endpoints for a larger pivotal trial. It does not report further eligibility criteria or describe the enrolled population in detail.
Intervention
The intervention was the Orbital Atherectomy System. In this arm, orbital atherectomy was performed before adjunctive balloon angioplasty. The primary endpoint was assessed after balloon angioplasty.
Comparator
The comparison group received balloon angioplasty alone. The trial used randomized allocation and a parallel-group design, with no masking reported.
Primary question
The primary question was whether the groups differed on the percentage of calcium removal out of lumen gain, assessed by IVUS after balloon angioplasty. The registry reports group medians and inter-quartile ranges and a Wilcoxon (Mann-Whitney) test. The posted results describe this imaging endpoint; they do not by themselves establish how patients felt or functioned, or whether any difference translated into a clinical benefit.
3. Trial Design
CLARITY I (NCT01941030) is recorded as a completed, randomized, parallel-group pilot study. It enrolled 51 participants. The registry lists 25 in the Orbital Atherectomy System arm and 26 in the Balloon Angioplasty arm. Masking is recorded as none. The phase is listed as NA. Abbott Medical Devices is named as the sponsor.
The intervention contrast was orbital atherectomy performed before adjunctive balloon angioplasty versus balloon angioplasty alone. The primary endpoint was an IVUS-based measure assessed after balloon angioplasty. Fractional Flow Reserve is listed as a secondary outcome. The registry lists eight outcome measures and nine analyses, but does not report a full statistical analysis plan or explain how each analysis relates to the outcome measures.
The record describes CLARITY I as a pilot intended to identify clinically appropriate endpoint or endpoints for a larger, statistically powered pivotal trial. It does not report the protocol details, sample-size justification, or the process used to select endpoints for that later study. The listed enrollment and arm sizes describe the trial record; they should not be taken to establish how many participants had evaluable data for the primary endpoint. The registry notes that not all subjects had reported IVUS data for each lesion before and after treatment.
The record gives the study status as completed and lists the start as 2013-03 and primary completion as 2015-06. Those dates describe the study record, not the duration of follow-up for each participant. Follow-up details are not reported in the registry record.
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 | Orbital Atherectomy System | Balloon Angioplasty |
|---|---|---|
| STARTED | 25 | 26 |
| COMPLETED | 12 | 13 |
| NOT COMPLETED | 13 | 13 |
Reasons for not completing this period:
| Reason | Orbital Atherectomy System | Balloon Angioplasty |
|---|---|---|
| Death | 3 | 2 |
| Lost to Follow-up | 6 | 5 |
| Withdrawal by Subject | 4 | 6 |
Analysis population for the primary outcome, as defined in the registry: Not all subjects had reported IVUS data for each lesion pre- and post-treatment.
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 | Orbital Atherectomy System | Balloon Angioplasty | Total |
|---|---|---|---|---|
| Participants analysed | 25 | 26 | 51 | |
| Age, Continuous | years | 65.3 (SD 11.3) | 69.4 (SD 12.4) | 67.4 (SD 11.9) |
| Sex: Female, Male: Female | Participants | 3 | 12 | 15 |
| Sex: Female, Male: Male | Participants | 22 | 14 | 36 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 6 | 3 | 9 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 19 | 23 | 42 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 8 | 8 | 16 |
| Race (NIH/OMB): White | Participants | 17 | 18 | 35 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | participants | 25 | 26 | 51 |
| Number of treated lesions | lesions | 26 | 26 | 52 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Calcium Removal Out of Lumen Gain as Assessed by IVUS, measured over Post-balloon angioplasty.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Inter-Quartile Range |
| Unit | percentage of lumen gain |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the percentage of calcium removal out of lumen gain, assessed by IVUS after balloon angioplasty. The registry defines it at the maximum calcium ablation site. It describes a positive value as a reduction in calcium out of the lumen gain. In practical terms, the measure relates calcium removal to the gain in the vessel lumen observed at the assessed site; it is an imaging measure rather than a direct measure of symptoms or other clinical outcomes.
The endpoint is reported as a median with an inter-quartile range. The Orbital Atherectomy System arm had a median of 25.0, with an inter-quartile range of 11.1 to 42.9. The Balloon Angioplasty arm had a median of 0.0, with an inter-quartile range of 0.0 to 6.7. The unit is percentage of lumen gain. These summaries describe the observed distributions as posted and should not be read as averages.
IVUS provides an imaging-based way to assess vessel and lesion characteristics. A relative measure can describe calcium removal in relation to lumen gain, rather than reporting either feature in isolation. That can be useful when evaluating a device procedure in a pilot study focused on candidate endpoints. The registry does not report validation of this endpoint, a minimally important difference, or how it relates to patient-centered outcomes.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary outcome summaries show different observed distributions between the randomized groups. The median percentage of calcium removal out of lumen gain was 25.0 in the Orbital Atherectomy System arm, with an inter-quartile range of 11.1 to 42.9. In the Balloon Angioplasty arm, the median was 0.0, with an inter-quartile range of 0.0 to 6.7. The registry reports a Wilcoxon (Mann-Whitney) comparison with p = 0.022.
The p-value describes how compatible the observed rank-based comparison is with a null model of no group difference, under the assumptions of that test. It is not the probability that the null hypothesis is true, and it does not quantify the size or clinical importance of a difference. The registry does not report a confidence interval or a test statistic for this comparison. The median and inter-quartile range provide information about the center and spread of each group’s endpoint values, but they do not show every individual value or the full distributions.
The reported comparison is an imaging endpoint after balloon angioplasty. It does not establish that the groups differed in clinical outcomes, and it does not by itself establish that the observed endpoint difference matters to patients. Fractional Flow Reserve is listed as a secondary outcome, but its results are not described in the registry record for this interpretation. The registry lists eight outcome measures and nine analyses, without identifying a complete hierarchy of outcomes or analyses. This makes it difficult to place the primary result in the context of all analyses conducted.
The record also notes that not all subjects had reported IVUS data for each lesion before and after treatment. The number of evaluable observations for the primary endpoint and the handling of missing measurements are not reported in the registry record. The arm counts therefore should not be assumed to be the denominators for every endpoint analysis. Missing imaging data can affect how representative the reported summaries are of the randomized groups, depending on why data are absent and how the analysis handled them.
Because this was a pilot intended to inform a larger trial, the result is best understood as an estimate from an exploratory study rather than as a definitive treatment comparison. The registry does not report a planned sample-size justification or a prespecified decision rule for advancing endpoints. The posted result identifies a group difference on the recorded imaging measure; it does not resolve broader clinical questions or establish how precisely the effect would be estimated in a larger study.
9. Statistical Methods Explained
The primary endpoint is summarized using medians and inter-quartile ranges. A median identifies the central value in an ordered set of observations. The inter-quartile range describes the interval from the lower to the upper quartile, capturing the middle portion of the observed distribution. These summaries can be useful when values are skewed or include extreme observations because they are less influenced by extremes than the mean and standard deviation. That is general statistical context; the registry does not report the shape of the endpoint distributions.
What does the Wilcoxon (Mann-Whitney) test compare?
The registry names the Wilcoxon (Mann-Whitney) method for the comparison between the arms. In general, this is a rank-based method: observations from both groups are ordered together, and the comparison uses their ranks. It tests whether values in one group tend to rank higher or lower than values in the other group. It is often described as a test of distributions. It is not automatically a test of medians alone; a median-focused interpretation requires additional assumptions about the distributions, such as similar shapes.
The posted p-value is 0.022. In general, a p-value measures how unusual data at least as incompatible with a specified null model would be if that model and the test assumptions were true. It does not give the probability that the null model is true, nor does it measure the magnitude of an effect. The registry does not report the test statistic, an effect estimate for the comparison, or a confidence interval. Those omissions limit how fully the reported test can be assessed from the registry record.
How should the summaries be read alongside the test?
The medians and inter-quartile ranges describe the observed endpoint values within each arm. The Wilcoxon result supplies a group comparison based on ranks. These are complementary forms of information: the summaries convey the scale and spread of the posted values, while the test gives a measure of statistical evidence against its null model. Neither substitutes for a confidence interval, which in general describes a range of effect estimates compatible with the data and the interval procedure. No confidence interval for the primary comparison is reported in the registry record.
The reported values are a median of 25.0 with an inter-quartile range of 11.1 to 42.9 for the Orbital Atherectomy System arm, and a median of 0.0 with an inter-quartile range of 0.0 to 6.7 for the Balloon Angioplasty arm. The test result is p = 0.022. No new difference or ratio is calculated from these summaries. The endpoint is described as a percentage of lumen gain, and its assessment is tied to the maximum calcium ablation site after balloon angioplasty.
Why does over-dispersion matter in general?
Over-dispersion occurs when data vary more than a statistical model expects. If a method assumes less variability than the data actually contain, uncertainty can be understated and inferential results can be unreliable. Rank-based methods avoid some distributional requirements associated with parametric comparisons, but they do not remove the need to understand the data structure, independence of observations, missingness, or the analysis population. The registry does not report an assessment of over-dispersion or describe checks of model assumptions. The primary test is identified as Wilcoxon (Mann-Whitney), rather than as a model-based analysis.
Lesion-level imaging data may have a structure that matters for analysis if observations are clustered within participants. The registry states that not all subjects had reported IVUS data for each lesion before and after treatment, but it does not say how many lesions or measurements contributed, whether multiple lesions were included per participant, or how any within-participant dependence was handled. Those details are not reported in the registry record, so the implications for the test cannot be resolved from the posted description.
What does the planning illustration represent?
General sample-size calculations use assumptions about the effect to detect, variability, significance level, allocation, and statistical method. The planning illustration associated with this study is described as based on the observed effect, with a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. It considers the stated fraction of the observed effect. Such calculations are planning illustrations, not observed power and not evidence that the trial had a particular probability of detecting an effect. The registry does not report that these assumptions were the trial’s own design assumptions or provide a sample-size justification for the pilot.
For comparisons that are not time-to-event analyses, planning results are expressed as participants per arm for 80% power or another stated power level, as applicable to the associated calculations. Time-to-event illustrations use total events. No particular calculated planning values are reported in the registry record. A pilot study’s observed effect can be imprecise, so using it as a planning input should not be mistaken for a reliable forecast of the effect in a future trial.
Finally, the registry lists eight outcome measures and nine analyses. A complete statistical methods account would ordinarily clarify outcome hierarchy, analysis populations, handling of missing data, multiplicity procedures, and any prespecified adjustments. Those details are not reported in the registry record. Their absence does not change the reported test result, but it limits assessment of how the analysis was planned and how the primary comparison fits among the other analyses.
10. Analyses Reported by the Sponsor
| Method | Estimate | 95% CI | P-value |
|---|---|---|---|
| Wilcoxon (Mann-Whitney) | not reported | 0.022 |
The registry’s reported comparison is a Wilcoxon (Mann-Whitney) test, with p = 0.022. The group summaries are medians and inter-quartile ranges: 25.0, with 11.1 to 42.9, for the Orbital Atherectomy System arm, and 0.0, with 0.0 to 6.7, for the Balloon Angioplasty arm. This describes the sponsor’s posted analysis of the primary endpoint.
The registry record does not report a separately recalculated test result, effect estimate, or confidence interval for this comparison. No discrepancy between the sponsor analysis and a recalculation is identified in the registry record. Accordingly, the reported sponsor analysis remains the available inferential result; there is no alternative recalculated result in the registry record to set alongside it.
The reported p-value should be read together with the endpoint summaries and the limitations in the record. A p-value does not convey the size or clinical importance of an effect, and the registry does not report a confidence interval for the comparison. The record also notes incomplete availability of IVUS data by lesion and does not describe the missing-data method or analysis population. Those issues limit the extent to which the posted comparison can be independently assessed.
11. Multiplicity, Missing Data and Analysis Populations
The registry lists eight outcome measures and nine analyses. Fractional Flow Reserve is identified as a secondary outcome. The primary endpoint is the IVUS-based percentage of calcium removal out of lumen gain. The record does not report a complete hierarchy of outcomes, a prespecified analysis plan, or whether and how multiplicity was addressed. It is therefore not possible to determine from the registry record whether the reported p-value was adjusted for the number of outcomes or analyses, or whether the primary endpoint and analysis were selected before results were examined.
Multiplicity is a general statistical concern when several outcomes or comparisons are assessed. As the number of analyses increases, the chance of at least one apparently notable result can increase if each is considered without adjustment. This general point does not establish that the reported result is false or that a particular adjustment was required; it explains why knowing the prespecified analysis hierarchy and multiplicity approach matters. Neither is reported in the registry record.
The primary endpoint description states that not all subjects had reported IVUS data for each lesion before and after treatment. The registry does not state how much data were missing, why measurements were unavailable, how missing measurements were handled, or how many participants and lesions were included in the endpoint analysis. It also does not report whether the analysis followed an intention-to-treat, per-protocol, or other analysis population. The listed arm counts should not be treated as confirmation that all participants contributed endpoint data.
These omissions affect interpretation of both the precision and representativeness of the reported result. If the availability of imaging data is related to participant characteristics, treatment, or outcomes, an analysis of available measurements could differ from an analysis of all randomized participants. That is a general possibility, not a claim about what occurred in this trial. The registry does not provide enough detail to evaluate the missingness mechanism or the robustness of the primary comparison to missing data.
12. 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 |
|---|---|---|---|
| Orbital Atherectomy System | 22 | 25 | 88.0% |
| Balloon Angioplasty | 17 | 26 | 65.4% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Orbital Atherectomy System | 3 of 25 |
| Balloon Angioplasty | 3 of 26 |
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 |
|---|---|
| Orbital Atherectomy System | 4 of 25 |
| Balloon Angioplasty | 8 of 26 |
Most frequent serious adverse event terms
| Event term | Organ system | Orbital Atherectomy System | Balloon Angioplasty |
|---|---|---|---|
| Minor amputation - pre-planned, index limb | Surgical and medical procedures | 2 of 25 | 4 of 26 |
| Revascularization, index limb (TLR) | Surgical and medical procedures | 3 of 25 | 3 of 26 |
| Revascularization, non-index limb | Surgical and medical procedures | 4 of 25 | 2 of 26 |
| Congestive Heart Failure | Cardiac disorders | 2 of 25 | 2 of 26 |
| Minor amputation, index limb due to gangrene | Surgical and medical procedures | 2 of 25 | 2 of 26 |
| Revascularization, index limb (non-TVR) | Surgical and medical procedures | 1 of 25 | 3 of 26 |
| Cellulitis, index limb | Musculoskeletal and connective tissue disorders | 1 of 25 | 2 of 26 |
| Coronary Artery disease, worsening | Cardiac disorders | 1 of 25 | 2 of 26 |
| Death, unknown cause | General disorders | 2 of 25 | 1 of 26 |
| Major amputation, index limb due to gangrene | Surgical and medical procedures | 2 of 25 | 1 of 26 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Orbital Atherectomy System | Balloon Angioplasty |
|---|---|---|---|
| Dissection | Injury, poisoning and procedural complications | 1 of 25 | 5 of 26 |
| Vessel spasm | Injury, poisoning and procedural complications | 3 of 25 | 0 of 26 |
| Access site bleeding | Injury, poisoning and procedural complications | 0 of 25 | 1 of 26 |
| Lower extremity edema | General disorders | 0 of 25 | 1 of 26 |
| Pseudoaneurysm, access site | Injury, poisoning and procedural complications | 0 of 25 | 1 of 26 |
| Slow flow | Injury, poisoning and procedural complications | 0 of 25 | 1 of 26 |
| Urinary tract infection | Renal and urinary disorders | 0 of 25 | 1 of 26 |
Serious events with the highest arm-level rate: revascularization, non-index limb (16.0%), minor amputation - pre-planned, index limb (15.4%), revascularization, index limb (tlr) (12.0%), recoil (11.5%), revascularization, index limb (non-tvr) (11.5%).
The registry reports serious adverse events for 22 of 25 participants at risk in the Orbital Atherectomy System arm and 17 of 26 participants at risk in the Balloon Angioplasty arm. It reports other adverse events for 4 of 25 and 8 of 26 participants at risk, respectively. Deaths are listed as 3 in each arm. These are counts in the registry record, not an adjusted comparison between groups.
The serious adverse event terms listed with percentages are Revascularization, non-index limb (16.0%); Minor amputation - pre-planned, index limb (15.4%); Revascularization, index limb (TLR) (12.0%); Recoil (11.5%); Revascularization, index limb (non-TVR) (11.5%); and Congestive Heart Failure (8.0%). The record does not explain the denominators used for these percentages or whether participants could contribute to more than one term. The terms should not be added together or interpreted as mutually exclusive categories.
The registry does not report a statistical comparison of adverse events, follow-up duration for these counts, or attribution of events to treatment. Differences in raw counts alone do not establish a causal safety difference. These summaries describe the reported event information; they do not provide a complete safety assessment or a basis for individual medical decisions.
13. What the Result Does, and Does Not, Mean
The posted result concerns a specific IVUS-based endpoint measured after balloon angioplasty: percentage of calcium removal out of lumen gain at the maximum calcium ablation site. The Orbital Atherectomy System arm had a reported median of 25.0 and inter-quartile range of 11.1 to 42.9; the Balloon Angioplasty arm had a median of 0.0 and inter-quartile range of 0.0 to 6.7. The registry reports a Wilcoxon (Mann-Whitney) p-value of 0.022 for the comparison.
These data support a description of different observed group distributions on this endpoint in this pilot study. They do not establish that a treatment works or does not work. The endpoint is an imaging measure, and the record does not establish its relationship to patient-centered outcomes, its clinical importance, or a minimally important difference. The result does not answer whether participants experienced different symptoms, function, quality of life, or other clinical outcomes.
The registry describes the study as intended to identify appropriate endpoints for a larger, statistically powered pivotal trial. A pilot result can inform questions for later research, but it does not substitute for that larger trial. The record does not report the sample-size justification, a confidence interval for the primary comparison, or sufficient analysis details to judge the precision and robustness of the result fully. Not all subjects had reported IVUS data for each lesion before and after treatment, and the handling of this missing information is not reported.
The safety counts are descriptive and do not establish that an event was caused by a study intervention. Likewise, a statistically notable result on the primary imaging endpoint should not be treated as evidence about the overall balance of clinical benefits and harms. The registry’s outcome and analysis counts, without a reported multiplicity strategy or complete analysis hierarchy, further limit interpretation of the primary p-value in the broader set of analyses.
In short, the record reports a group difference on the specified imaging measure, together with incomplete information about endpoint availability and analysis methods. It does not determine the clinical meaning of that difference or resolve the questions that a larger pivotal study would need to address.
14. Why This Trial Matters Statistically
CLARITY I illustrates the statistical role of a pilot study: it can examine candidate measurements and help identify endpoints for later evaluation. The registry explicitly describes this study as a pilot intended to identify clinically appropriate endpoints for a larger, statistically powered pivotal trial. Its primary outcome is an imaging measure of calcium removal in relation to lumen gain, rather than a direct clinical outcome.
The reported medians and inter-quartile ranges make the observed endpoint distributions interpretable alongside the rank-based comparison. The Wilcoxon (Mann-Whitney) p-value of 0.022 indicates that the posted analysis found evidence against its null model for this endpoint. At the same time, the registry does not report a confidence interval or an effect estimate for the comparison, so the precision of the group contrast is not fully described.
The record also shows why analysis populations and missing-data reporting matter. It states that not all subjects had reported IVUS data for each lesion before and after treatment, yet does not give the endpoint analysis population or explain how missing measurements were handled. Those details are essential to understanding what observations the reported summaries represent.
Finally, the record lists multiple outcome measures and analyses but does not describe a multiplicity approach or full analysis hierarchy. These are not merely technical details: they shape how readers should interpret an isolated p-value and how confidently a pilot result can guide future study planning. The study is statistically informative as an endpoint-focused pilot, but the record leaves important questions for a later, more fully specified trial.
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.
Several limitations are specific to the available record. First, the primary endpoint depends on IVUS measurements, and the registry notes that not all subjects had reported data for every lesion before and after treatment. It does not report how many endpoint observations were available, why data were absent, or how missing measurements were handled. The number of participants contributing to the primary comparison is therefore not clear from the endpoint description.
Second, the study is described as a pilot for endpoint selection, not as a definitive pivotal trial. The record does not report a sample-size justification or a prespecified target for the primary comparison. The posted group summaries and p-value should consequently be interpreted in that pilot context, rather than as a complete assessment of the likely size or precision of an effect in a later study.
Third, the registry reports a rank-based test and p-value but not a confidence interval, test statistic, or separate effect estimate. It does not report whether the test’s assumptions were assessed, whether lesion-level observations were clustered within participants, or how the analysis population was defined. Those details are not reported in the registry record.
Fourth, the registry lists eight outcome measures and nine analyses but does not describe the prespecified outcome hierarchy or any multiplicity procedure. It also identifies Fractional Flow Reserve as a secondary outcome without reporting its result in the registry record used for this account. The absence of those details limits comparison of the primary result with the wider set of study analyses.
Finally, the record’s adverse-event counts do not include a reported comparative safety analysis, event attribution, or a follow-up description for those counts. They should be read as descriptive registry figures, not as a complete evaluation of the comparative safety profile.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Complete Lesion Assessment With ffR and IVUS TechnologY — NCT01941030.
- Registry record last updated 2023-07-18; status last verified 2023-07.
- Results first posted 2019-01-24.
- 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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19. Record Summary
CLARITY I, formally titled Complete Lesion Assessment With ffR and IVUS TechnologY (CLARITY I), is recorded as NCT01941030. Abbott Medical Devices is the sponsor. The study is completed, randomized, parallel-group, and unmasked, with enrollment of 51. The listed conditions are peripheral artery disease and critical limb ischemia.
The trial compared orbital atherectomy followed by balloon angioplasty with balloon angioplasty alone. The primary endpoint was the post-balloon angioplasty percentage of calcium removal out of lumen gain, assessed by IVUS. The registry reports medians of 25.0 and 0.0, with inter-quartile ranges of 11.1 to 42.9 and 0.0 to 6.7, respectively, and a Wilcoxon (Mann-Whitney) p-value of 0.022.
The study is described as a pilot intended to help identify endpoints for a larger pivotal trial. The record notes incomplete IVUS data availability and does not report the missing-data approach, full analysis populations, or multiplicity strategy.