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 Efficacy of Intercostal CryoAnalgesia in Robotic Lung Resection (NCT05144828), a randomized phase 4 study. The primary outcome is Change in Visual Analogue Scale (VAS) Pain Score.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05144828 |
| Phase | Phase 4 |
| Condition | Pain, Postoperative, Lung Diseases |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 33 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Medical College of Wisconsin |
| Results posted | Yes |
2. Clinical Question
Population
Patients undergoing robot-assisted anatomic lung resection. The registry describes the study as a single-center, single-surgeon trial and lists an enrollment of 33 participants.
Intervention
Intercostal nerve cryoablation added to standard-of-care pain control. The arm description specifies cryoablation of intercostal nerves 4-9, an intercostal nerve block, and prescribed postoperative pain medication.
Comparator
Standard-of-care pain control without cryoablation. This arm also received an intercostal nerve block of nerves 4-9 and prescribed postoperative pain medication.
Primary question
How does the change in Visual Analogue Scale pain score compare between the two groups across the postoperative assessment period? The registry record does not report the comparative results.
The trial asks whether adding intercostal nerve cryoablation to the described pain-control regimen is associated with a different postoperative pain-score course than the regimen without cryoablation. It is a randomized, parallel-group comparison, so participants were assigned to one of two groups rather than each participant receiving both approaches. The registry identifies the study as single-masked but does not report who was masked or how masking was implemented.
The primary outcome is described as change in Visual Analogue Scale pain score. The listed assessment timeframe includes 14 days post-operatively and days 30, 60, 90, 120, 150, and 180. The outcome description also calls the measure a Daily VIS Score. The registry record does not clarify how daily scores were summarized at the listed assessment points or specify which time-point comparison was intended to answer the primary question.
The registry lists the M.D. Anderson Symptom Inventory score and Leeds Assessment of Neuropathic Symptoms and Signs score as secondary outcomes. It does not report their results. The clinical question is therefore identifiable, but the posted record does not show the estimates needed to judge the size, direction, or precision of any difference in pain scores or secondary measures.
3. Trial Design
The registry describes a Phase 4, randomized, single-masked, parallel-group trial. The brief summary characterizes it as prospective, single-center, and conducted by a single surgeon. Enrollment is listed as 33. The trial status is completed, with a start date of 2022-02-15 and primary completion date of 2024-10-04.
Participants were assigned to one of two groups. The cryoablation group received intercostal nerve cryoablation plus standard-of-care pain control. Its arm description names the CryoICE® CRYOS-L cryoablation probe, an intercostal nerve block of nerves 4-9 using 0.5% Marcaine with Epinephrine, and prescribed postoperative medication including tramadol, tylenol, and robaxin. The comparison group received the same described nerve block and postoperative medications, without the listed cryoablation procedure. Patient-controlled analgesia is listed among the interventions, but its use by group is not detailed in the arm descriptions.
Random assignment supports a comparison of the groups as assigned, but details that would help assess how assignment was carried out are not reported in the registry record. The record does not describe the randomization sequence, allocation concealment, masking procedures, or adherence to assigned care. It also does not report whether participants could receive additional pain treatments or how those would be handled in analysis.
The posted primary outcome covers several postoperative time points rather than a single listed assessment. This matters because repeated measurements on the same participant are related, and an analysis must specify how those measurements are used to estimate a group difference over time. The registry record does not report the planned analysis model, the primary time point, or a single summary contrast.
The arm-level safety counts list 17 participants at risk in the cryoablation group and 16 in the standard-of-care group. These counts match the enrollment total, but the registry record does not describe analysis populations for the primary outcome or explain whether all randomized participants contributed outcome measurements.
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 | Intercostal Nerve Cryoablation Plus Standard of Care (SOC) Pain Control | Standard of Care (SOC) Pain Control |
|---|---|---|
| STARTED | 17 | 16 |
| COMPLETED | 15 | 15 |
| NOT COMPLETED | 2 | 1 |
Analysis population for the primary outcome, as defined in the registry: Daily VIS Score
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 | Intercostal Nerve Cryoablation Plus Standard of Care (SOC) Pain Control | Standard of Care (SOC) Pain Control | Total |
|---|---|---|---|---|
| Participants analysed | 17 | 16 | 33 | |
| Age, Continuous | years | 68.1 (SD 6.3) | 65.3 (SD 13.8) | 66.7 (SD 10.4) |
| Sex: Female, Male: Female | Participants | 13 | 8 | 21 |
| Sex: Female, Male: Male | Participants | 4 | 8 | 12 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 1 | 0 | 1 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 1 | 1 |
| Race (NIH/OMB): White | Participants | 16 | 15 | 31 |
| 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 | 17 | 17 | 33 |
6. Primary Endpoint
The registry lists the primary outcome as Change in Visual Analogue Scale (VAS) Pain Score, measured over 14 Days post-operatively, day 30, day 60, day 90, day 120, day 150, day 180.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | scores on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is titled “Change in Visual Analogue Scale (VAS) Pain Score.” The registry describes a patient self-assessment scale from 0-10, where 0 means no pain and 10 means worst possible pain. Pain scores are used to describe a participant’s reported symptom intensity, and repeated assessments can show how that report changes over the postoperative period.
The listed timeframe includes 14 days post-operatively and days 30, 60, 90, 120, 150, and 180. The outcome description refers to a “Daily VIS Score,” while the title uses “VAS Pain Score.” The registry record does not explain whether “VIS” is a separate label, how daily assessments were summarized, or which of the listed time points defines the primary comparison.
For a continuous outcome, a group mean describes the average score within a group, while the standard deviation describes variation among individual scores. A difference in group means can summarize the contrast, but its interpretation depends on the time point or longitudinal summary being compared. A confidence interval would show the range of effect estimates reasonably compatible with the observed data under the analysis assumptions. No group means, standard deviations, effect estimates, or confidence intervals for this endpoint are reported in the registry record.
Repeated pain assessment can be useful for describing the course of symptoms rather than relying on one observation. However, conclusions about that course require a stated model and a clear approach to missing assessments. Neither is reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a randomized comparison of intercostal nerve cryoablation plus standard-of-care pain control against standard-of-care pain control alone. It also identifies postoperative pain score change as the primary outcome. The record does not report the group-level pain scores or a comparative estimate. Consequently, the direction and magnitude of the observed pain-score contrast cannot be described from this record.
No confidence interval or p-value for the primary outcome is reported in the registry record. Without an effect estimate and its uncertainty, the posted information does not establish whether the groups differed, how large any difference may have been, or how precisely it was estimated. The absence of a reported analysis is not evidence that the groups were the same; it means the comparison cannot be evaluated from the outcome information.
The endpoint includes multiple postoperative assessments: 14 days post-operatively and days 30, 60, 90, 120, 150, and 180. A result at one assessment would not necessarily describe the pattern at the others. A longitudinal analysis might estimate an overall group contrast, differences at specific time points, or a group-by-time pattern, but the registry record does not state which question was analyzed. It reports zero analyses and does not provide a primary outcome result.
The registry lists 33 enrolled participants. The safety counts show 17 at risk in the cryoablation group and 16 in the standard-of-care group. Those totals describe the safety groups in the posted record; they do not indicate how many contributed complete pain measurements. The analysis population and outcome-specific participant counts are not reported in the registry record.
The posted record lists two secondary measures, the M.D. Anderson Symptom Inventory score and the Leeds Assessment of Neuropathic Symptoms and Signs score, but no results for them. It is therefore not possible to compare the primary and secondary findings or assess whether any pattern was consistent across measures.
Overall, the record describes the question, groups, and outcome schedule, but does not provide the numerical outcome analyses needed to interpret efficacy. Statistical interpretation should remain limited to that distinction: the trial was designed to make a randomized comparison, while its registry record does not display the comparative pain results.
9. Statistical Methods Explained
What does a group mean describe?
For a continuous measure such as a pain score, the mean summarizes the average score among participants included in a group at a specified assessment. A comparison of means can express the average difference between groups. The registry identifies the primary parameter as a mean and the dispersion measure as a standard deviation. It does not report the group means or standard deviations for the primary outcome, so a numerical comparison cannot be interpreted.
A standard deviation describes how spread out individual observations are around a group mean. It is not the same as the uncertainty in the estimated group mean. General explanation: a confidence interval for a treatment contrast reflects uncertainty in that estimated contrast, incorporating the amount of information and variability in the observations under the model used. No such interval is reported for the primary outcome.
Why does the time structure matter?
The primary outcome lists several postoperative assessment points, and the description also refers to a daily score. Repeated observations from the same person are generally related rather than independent. General explanation: an analysis of repeated measurements needs to account for that within-person relationship; treating every observation as unrelated can misstate uncertainty. The registry record does not report whether a repeated-measures model was used, how daily scores were handled, or which time point or summary was primary.
Different approaches answer different questions. A comparison at one named assessment estimates a contrast at that point. A model using measurements over time can describe an average pattern or test whether the groups’ trajectories differ. Those are not interchangeable estimands. Since no analysis model or primary contrast is reported, the intended statistical interpretation of the multiple time points is not clear from the registry record.
What would a confidence interval contribute?
General explanation: an effect estimate gives the magnitude and direction of a comparison, while a confidence interval conveys its precision. A narrow interval indicates greater precision than a wide interval, conditional on the model and data. An interval spanning values on both sides of no difference may be compatible with effects in either direction. That interpretation still depends on the analysis being appropriate and the interval being reported. The registry record includes no primary endpoint estimate or confidence interval.
How should p-values be read?
General explanation: a p-value summarizes how unusual results at least as extreme as the observed result would be under a specified null model and its assumptions. It does not measure the probability that the null hypothesis is true, the size of an effect, or whether a result is important to patients. A p-value is most informative alongside an effect estimate and uncertainty interval. No p-value for the primary outcome is reported in the registry record.
What is the role of multiplicity?
Testing more than one time point or outcome can create a multiplicity issue: the chance of at least one apparently notable result can increase when many comparisons are examined. General explanation: a prespecified primary contrast and an appropriate multiplicity strategy can help keep interpretation aligned with the question. The record lists multiple pain assessment points and secondary outcomes but does not report a multiplicity plan, a hierarchy of tests, or which comparisons were conducted. No adjustment should be presumed.
What does over-dispersion mean?
General explanation: over-dispersion refers to observed variability greater than a statistical model expects. It is especially relevant for some count or binary outcomes. The primary endpoint is described as a continuous mean score with standard deviation, not as a count outcome. The registry record does not report a model or diagnostics, so no claim about over-dispersion or model adequacy can be made for this analysis.
What can planning calculations tell us?
General explanation: a sample-size calculation is a planning exercise based on assumptions about the effect to detect, variability, significance level, allocation, and analysis. It is not a measure of the probability that a completed trial detected an effect. The sample-size assumptions described for the page characterize any resulting figures as planning illustrations based on an observed effect, with two-sided significance level 0.05, equal allocation, and a normal approximation. Such illustrations should not be read as observed power. The registry record does not report the trial’s own sample-size justification, and the posted record contains no primary effect estimate from which to assess the trial’s findings.
In short, the registry supplies enough design information to identify the broad comparison and outcome but not enough analysis detail or numerical results to reproduce or evaluate the primary statistical inference. The analysis model, primary contrast, assumptions, and uncertainty estimates are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The primary pain outcome is assessed at several postoperative time points, and the registry also lists two secondary outcomes: M.D. Anderson Symptom Inventory score and Leeds Assessment of Neuropathic Symptoms and Signs score. Examining many outcomes or time points raises a multiplicity question. General explanation: when several comparisons are tested, an isolated result can appear notable by chance more often than in a single prespecified comparison. A prespecified testing hierarchy or other multiplicity approach can clarify how multiple findings should be interpreted. The registry record does not report such a plan, identify a single primary time point, or state which outcome comparisons were tested.
The record does not report a missing-data method, the number of participants with observed primary outcome measurements at each assessment, or reasons for missing measurements. These details matter because incomplete follow-up can affect both the estimate and its precision, particularly when missingness differs between groups or relates to pain. General explanation: methods for handling missing measurements rely on assumptions, and those assumptions should be described alongside the analysis.
The record also does not identify the primary analysis population or state whether participants were analyzed according to randomized assignment. The arm-level safety counts list 17 and 16 participants at risk, but these figures do not establish the number included in each primary outcome analysis. The randomization procedure, exclusions, protocol deviations, and analysis-population definitions are not reported in the registry record.
Because the posted record reports zero analyses and no outcome estimates, it is not possible to determine how missing observations, multiple comparisons, or analysis populations were handled. These are gaps in the available registry information, not evidence that a particular method was or was not used.
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 |
|---|---|---|---|
| Intercostal Nerve Cryoablation Plus Standard of Care (SOC) Pain Control | 0 | 17 | 0.0% |
| Standard of Care (SOC) Pain Control | 0 | 16 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Intercostal Nerve Cryoablation Plus Standard of Care (SOC) Pain Control | 0 of 17 |
| Standard of Care (SOC) Pain Control | 0 of 16 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Intercostal Nerve Cryoablation Plus Standard of Care (SOC) Pain Control | 3 of 17 |
| Standard of Care (SOC) Pain Control | 3 of 16 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Intercostal Nerve Cryoablation Plus Standard of Care (SOC) Pain Control | Standard of Care (SOC) Pain Control |
|---|---|---|---|
| Prolonged air-leak | Respiratory, thoracic and mediastinal disorders | 3 of 17 | 3 of 16 |
The registry lists zero serious adverse events among 17 participants at risk in the intercostal nerve cryoablation plus standard-of-care group, and zero among 16 participants at risk in the standard-of-care group. It lists three other adverse events in each group. No deaths are listed in either group.
These figures are counts as reported in the registry. The record does not provide event descriptions for the three “other” adverse events in each group, or clarify whether the counts refer to participants with at least one event or to event occurrences. It also does not report timing, severity, relatedness, duration, or how events were collected. The top serious adverse event terms list is empty.
Zero serious adverse events reported in these groups should be read as a description of the posted counts, not as proof that serious events cannot occur. General explanation: safety estimates depend on the number of participants observed, length and completeness of follow-up, event definitions, and ascertainment procedures. The registry record does not give enough detail to assess those features or to make a precise comparative safety estimate.
The posted safety counts do not provide a statistical comparison or uncertainty interval. They should therefore be interpreted as descriptive registry figures rather than as evidence of a demonstrated difference between groups.
12. What the Result Does, and Does Not, Mean
This trial addresses a specific comparison: adding intercostal nerve cryoablation to a standard-of-care pain-control regimen during robot-assisted anatomic lung resection, versus the listed standard-of-care regimen without cryoablation. The registry identifies randomization, the two groups, and postoperative pain scores as the primary outcome. These details make the intended clinical question understandable.
However, the registry record does not report the comparative pain results. It provides no group means, standard deviations, effect estimate, confidence interval, or p-value for the primary outcome. It also does not report results for the two listed secondary outcomes. Therefore, the posted information cannot show whether the groups’ pain scores differed, in which direction, by how much, or with what precision. It cannot support a conclusion that the added procedure did or did not change the measured outcomes.
The safety figures are also limited. The record reports zero serious adverse events in both groups, three other adverse events in each group, and zero deaths. The “other” events are not described, and the record does not provide enough detail to assess event ascertainment or make a precise comparative safety judgment.
General explanation: a statistically estimated difference and its uncertainty address a different question from whether an outcome matters to patients. Clinical interpretation generally needs the size and precision of the estimate, the outcome’s context, and the study’s limitations. Here, the registry does not provide the primary estimate or its uncertainty, so neither statistical nor clinical importance can be assessed from the posted results.
The conclusion is about what is available in the registry record, not about all results that may exist elsewhere. The record shows a completed randomized trial and its stated outcome framework, but the comparative analyses are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial is statistically notable for its repeated patient-reported pain assessments. The primary outcome lists 14 days post-operatively and days 30, 60, 90, 120, 150, and 180, while the outcome description refers to a daily score. Such a schedule can describe change over time, but it also requires a clear definition of the main comparison and a method that accounts for repeated measurements within participants.
That distinction is important when reading the posted record. A set of assessments can support several different analyses: a contrast at a selected assessment, a summary across assessments, or a comparison of trajectories. Each describes a different aspect of the outcome. The registry record does not identify which was the primary statistical contrast, and it reports no analyses. Readers therefore cannot tell what estimand the trial’s results were intended to represent.
The design also compares two regimens that share an intercostal nerve block and prescribed postoperative pain medication, with cryoablation as the listed addition in one group. That makes the intervention contrast clear at a broad level. At the same time, the registry record does not report how patient-controlled analgesia was used, how treatment adherence was assessed, or how additional pain treatment was handled.
Finally, the posted record illustrates why a completed status and an enrollment figure do not substitute for outcome estimates. Statistical interpretation needs results and precision, along with the analysis population and methods. Those details are not reported in the registry record. The record is useful for identifying the trial’s question and structure, but does not show the evidence needed to quantify the primary comparison.
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 main limitation for interpreting this trial from the registry record is the absence of comparative outcome analyses. Although the study is listed as completed and the primary outcome is described, the record reports no analysis and no primary outcome estimates. It therefore does not show the direction, size, or precision of the pain-score comparison.
The repeated-measure endpoint is not fully specified. Its title refers to change in VAS pain score, its description calls the measure a Daily VIS Score, and its timeframe lists several postoperative assessments. The registry record does not reconcile these labels, explain how daily observations were summarized, identify a single primary time point, or state the planned longitudinal contrast.
Important methods are not reported in the registry record: the randomization sequence and concealment, who was masked, the primary analysis model, the analysis population, handling of missing observations, and any adjustment for multiple outcomes or time points. The record also does not report a sample-size justification. Without these details, readers cannot assess whether the analysis followed the intended design or how sensitive it may be to assumptions.
The brief summary describes a single-center, single-surgeon study with enrollment of 33. This identifies the setting and scale stated in the record, but the registry does not provide enough information to assess representativeness or whether the results generalize beyond that setting. Moreover, because primary and secondary outcome results are absent, the limitations of the estimated effects cannot be judged directly.
Safety information is limited to group counts. Descriptions and details of the other adverse events, event ascertainment methods, and follow-up for safety are not reported in the registry record. These limitations apply to interpretation of the posted record; they do not establish what information may be available outside it.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Efficacy of Intercostal CryoAnalgesia in Robotic Lung Resection — NCT05144828.
- Registry record last updated 2026-04-15; status last verified 2026-03.
- Results first posted 2026-01-28.
- 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 completed, Phase 4, randomized, single-masked, parallel-group trial of intercostal nerve cryoablation during robot-assisted anatomic lung resection. It lists a single-center, single-surgeon study and enrollment of 33. The intervention group received cryoablation plus the described standard-of-care pain control; the comparison group received standard-of-care pain control alone.
The primary outcome is change in VAS pain score, with assessments listed from 14 days post-operatively through day 180. Secondary outcomes are the M.D. Anderson Symptom Inventory score and the Leeds Assessment of Neuropathic Symptoms and Signs score. The registry lists zero analyses and does not report comparative outcome results, estimates, confidence intervals, or p-values.
For safety, the record lists zero serious adverse events and zero deaths in each group, with three other adverse events in each group. The other events are not described. Statistical methods for repeated assessments, missing data, multiplicity, and analysis populations are not reported in the registry record.