A Study Assessing Perfusion Outcomes With PINPOINT® Near Infrared Fluorescence Imaging in Low Anterior Resection: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Study Assessing Perfusion Outcomes With PINPOINT® Near Infrared Fluorescence Imaging in Low Anterior Resection (NCT02205307), a randomized na study. The primary outcome is Anastomotic Leak Rate.

2. Clinical Question

This is a question about a surgical process and a postoperative event. Imaging was intended to assess tissue perfusion during the operation, while the primary outcome concerned anastomotic leaks after the procedure. The registry description does not establish that a change in perfusion assessment necessarily changes the leak outcome; that relationship is the subject of the clinical comparison, not an assumption to make when reading the record.

The intervention category combines two imaging devices. Consequently, the primary comparison as described is between the combined PINPOINT-or-SPY-Elite strategy and standard practice alone. The record does not report a separate primary comparison for PINPOINT versus SPY Elite, nor does it give device-specific counts for the primary endpoint. It also does not report details about how surgeons selected between the devices.

The stated mITT definition includes randomized subjects when surgery was initiated or at least one ICG injection was performed. This is narrower than simply describing everyone randomized, and the record does not give the number meeting those conditions. The registry’s enrollment is 347, but that enrollment figure should not be treated as the primary endpoint denominator or as the number analyzed. The analysis population and outcome denominator are not reported in the registry record.

3. Trial Design

The study is described as randomized, controlled, parallel, and multicenter. Its allocation is listed as randomized, and masking is listed as none. The record identifies the trial as terminated. Enrollment is 347. The study start is 2015-01, and primary completion is 2017-05. The phase is listed as NA.

The parallel design assigned participants to one of two surgical strategies: standard practice with additional intraoperative imaging using PINPOINT or SPY Elite, or standard practice alone. The two imaging devices appear together in the intervention description, so this record supports reading the primary comparison as a combined imaging strategy versus standard practice. It does not report a separate assignment or outcome analysis for each device.

Random allocation can help make comparison groups similar with respect to both measured and unmeasured factors, on average, when the trial is conducted and analyzed appropriately. It does not ensure that the groups are identical, and the record does not report the randomization method, allocation concealment, or group-specific baseline characteristics. Masking is listed as none; the record does not specify which trial roles, if any, were aware of treatment assignment beyond that designation.

The target condition list includes rectal cancer and rectosigmoid cancer. The primary outcome description concerns low anterior resection and postoperative anastomotic leak. The intervention arm descriptions specify that the surgeon’s standard practice continued in both groups, with imaging added in one group. The study therefore evaluates the imaging strategy as an adjunct to usual surgical practice, not as a replacement for that practice.

Although enrollment and timing are reported, the record does not explain the reason for termination, whether recruitment ended as planned, or whether the study stopped early. It does not report a planned sample-size justification, a statistical analysis plan, or the timing of any interim analyses. The registry record also does not report how many participants were assigned to each randomized group for the primary analysis or how many met the mITT definition.

Two secondary outcomes are named: Rate of SPY Visualization and Tissue Perfusion, and Incidence of Post-Operative Abscess Requiring Surgical Management. The record lists three outcome measures overall, but it does not give a complete set of comparative analysis results for the primary question. The existence of named outcomes alone does not show that an effect was estimated or establish the precision of any comparison.

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

Analysis population for the primary outcome, as defined in the registry: Modified Intent-to-Treat (mITT): the mITT analysis population includes all randomized subjects in whom a low anterior resection surgical procedure is initiated or at least one injection with ICG was performed.

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 Anastomotic Leak Rate, measured over Day 0 to Week 8 (+/- 2 weeks).

The primary endpoint is Anastomotic Leak Rate, expressed as a count of participants. It concerns postoperative leaks after low anterior resection, comparing the group receiving perfusion imaging as an adjunct to standard surgical practice with the group receiving standard practice alone. The stated assessment window is Day 0 to Week 8 (+/- 2 weeks).

An anastomotic leak is clinically relevant to this surgical setting because it is a postoperative complication involving the connection made during the operation. The endpoint is used to evaluate whether the intraoperative strategy is associated with a difference in this specific postoperative event. The registry record does not provide a clinical definition of anastomotic leak, the method used to confirm it, or details of adjudication. Those details should not be inferred from the endpoint name.

The outcome is listed as a count of participants with an event, making it a binary participant-level endpoint for a defined follow-up window: each participant either contributes an event or does not, according to the study’s outcome rules. This differs from a continuous measure such as a laboratory value, and it is not described as time-to-event. The record does not report a single numerator and denominator for either randomized group in the primary outcome results, nor a comparative estimate or uncertainty interval.

The analysis population is defined as mITT and includes randomized subjects in whom a low anterior resection procedure was initiated or at least one injection with ICG was performed. That definition determines who is intended to contribute to the endpoint analysis, but the registry record does not report how the definition was applied in practice, how missing outcome observations were handled, or the resulting group-specific denominators.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does randomization contribute?

In general, randomization assigns participants to study strategies by chance rather than by a clinician’s choice. When allocation is implemented as planned, it can reduce systematic differences between groups at the start of a study. Randomization does not guarantee balance in every characteristic, and it does not prevent bias arising from missing outcomes, deviations from the assigned strategy, or differences in outcome assessment.

This registry record identifies the allocation as randomized, but the method of sequence generation and allocation concealment is not reported. Allocation concealment concerns whether upcoming assignments could be anticipated before enrollment. Without those details, the presence of randomized allocation can be described, but its implementation cannot be assessed fully from this record.

What comparison is described?

The stated comparison is standard practice with PINPOINT or SPY Elite imaging added versus standard practice alone. The parallel model means participants were assigned to a study group rather than crossing between the strategies as described in the record. The record lists no masking. In general, lack of masking can matter when care decisions, event detection, or reporting could be influenced by knowledge of assignment. The record does not provide enough detail to determine whether or how awareness affected surgical care or endpoint assessment.

The two devices are grouped in one intervention description. That makes the registry’s main question a comparison of an imaging strategy with standard practice, not a direct comparison of the devices. No separate device-specific primary analysis is reported in the registry record.

How should a binary endpoint be understood?

The primary outcome is a participant count for an event within a stated follow-up window. In general, a binary outcome records whether a participant experienced the event under the endpoint definition. A group’s event frequency can be summarized using an event count and the number assessed, and a between-group analysis can estimate a contrast between groups. The particular contrast and model should be specified in the analysis plan. The registry record does not report the primary endpoint counts, denominators, effect estimate, or model.

A raw count by itself is difficult to interpret without knowing the number of participants assessed and the rules for determining whether an event occurred. A comparison also needs to account for the intended analysis population and missing outcome data. Here, the outcome unit is participants, the follow-up window is Day 0 to Week 8 (+/- 2 weeks), and the mITT definition is stated. The registry record does not report the primary endpoint data needed to reconstruct a comparison.

What does the mITT definition mean?

The record defines the mITT analysis population to include all randomized subjects in whom a low anterior resection procedure was initiated or at least one injection with ICG was performed. In general, an analysis population definition sets out which randomized participants contribute to an analysis. Modified Intent-to-Treat populations vary across trials, so the exact definition matters; the label alone does not establish which participants were included.

The record does not report how many randomized participants met this definition, whether any participants were excluded after randomization, or whether the outcome analysis followed the mITT definition as written. It also does not explain how participants with unknown leak status were treated. These omissions limit assessment of the analysis population and the potential influence of missing data.

How do confidence intervals and p-values help?

In general, an effect estimate describes the direction and magnitude of a group contrast, while a confidence interval communicates its statistical uncertainty. A narrow interval indicates greater precision than a wide interval, though precision does not determine whether an effect is clinically important. A p-value measures how compatible observed data are with a specified null hypothesis under the assumptions of the analysis. It does not give the probability that the null hypothesis is true, and it should not be interpreted without the estimate and its interval.

No primary comparative effect estimate, confidence interval, or p-value is reported in the registry record. As a result, the primary endpoint’s direction, size, and precision cannot be evaluated from this information. Nor can the absence of a reported p-value be treated as evidence that the groups were the same.

What do the planning assumptions mean?

In general, a sample-size calculation is a planning exercise: it asks how much information a proposed study might need under specified assumptions. It is not an observed result and does not establish the power achieved by a completed trial. The planning illustration associated with this record is described as based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is described as a stated fraction of the observed effect.

Those assumptions do not substitute for the trial’s own design rationale. The planned sample-size justification is not reported in the registry record. A planning illustration based on an observed effect depends on that effect and should not be read as evidence that the original trial was designed around it. It also should not be described as observed power. For non-time-to-event outcomes, the planning convention is participants per arm; the primary endpoint is a participant-count outcome, not a time-to-event outcome.

In general, over-dispersion matters when count data vary more than a chosen model expects, because standard errors based on the narrower variance assumption can be too small. That concept is not a basis for changing the analysis of this endpoint: the primary outcome is specified as participants with an event, and the registry record does not report a count model or over-dispersion assessment.

What is not available to evaluate?

The registry record does not report the statistical analysis plan, the primary comparison model, covariate adjustment, handling of missing outcomes, interim analyses, or multiplicity procedures. These are not details that can be inferred from the randomized design or the endpoint name. Without them and without a reported primary result, readers cannot assess the planned error-control strategy, the robustness of the analysis, or the sensitivity of the finding to alternative assumptions.

10. Multiplicity, Missing Data and Analysis Populations

The record names the primary endpoint and two secondary outcomes: Rate of SPY Visualization and Tissue Perfusion, and Incidence of Post-Operative Abscess Requiring Surgical Management. It lists three outcome measures overall, but does not report a complete set of comparative analyses. The analysis plan and any multiplicity procedure are not reported in the registry record.

Multiplicity arises in general when several hypotheses or outcomes are tested. If many comparisons are made, the chance of at least one apparently unusual result can increase unless the analysis plan addresses that issue. The record does not state whether secondary outcomes were tested formally, whether any adjustment was planned, or which outcomes were considered confirmatory. No claims about control of false-positive findings can be made from the available description.

The primary outcome is not reduced to one comparative result in the posted information, and the record lists no analyses. The reason noted is that the primary outcome has several categories or time points and was not reduced to one comparison. The underlying category-specific results and any analysis combining them are not reported in the registry record. Consequently, there is no single primary estimate to interpret alongside any secondary findings.

The mITT population is defined by randomization plus initiation of low anterior resection or at least one ICG injection. However, the record does not report the number in this population, group-specific endpoint denominators, missing outcome counts, reasons for missingness, or the method used to handle missing data. In general, missing outcomes can affect a comparison when the probability of missingness is related to treatment assignment or event status. The direction and extent of any such effect cannot be assessed without those details.

The registry record also does not report whether interim analyses were conducted or whether any stopping rule was used. The terminated status does not answer those questions. The analysis population, missing-data handling, multiplicity approach, and analysis plan should therefore be treated as not reported in the registry record rather than inferred.

11. 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 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: ileus (4.8%), anastomotic leak (4.8%), dehydration (4.8%), pelvic abscess (2.4%), small intestinal obstruction (2.3%).

The adverse-event summary lists serious-event counts for the PINPOINT or SPY Elite group, the STANDARD group, and a separate Not Treated group. Serious adverse events affected 44 participants among 171 at risk in the PINPOINT or SPY Elite group, 52 among 168 at risk in the STANDARD group, and 0 among 8 at risk in the Not Treated group. Other adverse events affected 155 participants among 171 at risk, 146 among 168 at risk, and 2 among 8 at risk, respectively. The record lists deaths as 3, 1, and 0 for these groups, respectively.

These are descriptive safety counts, not the primary endpoint comparison. The Not Treated group is reported separately and should not be assumed to be a randomized comparator. The record does not describe the reasons participants were not treated or provide an adjusted safety comparison. The serious-event terms listed include Ileus, Anastomotic Leak, and Dehydration at 4.8% each; Pelvic Abscess at 2.4%; Small Intestinal Obstruction at 2.3%; and Abdominal Abscess at 1.8%. The denominator and group distribution for these listed term percentages are not reported in the registry record.

In general, adverse-event counts need context about definitions, follow-up, and ascertainment. The registry record does not provide enough detail to establish whether these counts cover the same population or observation window as the primary endpoint. They should not be used to infer a comparative effect on anastomotic leak rate.

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

The record describes a randomized, parallel, multicenter study of perfusion imaging added to standard surgical practice during low anterior resection, compared with standard practice alone. Its primary question concerns postoperative anastomotic leaks over Day 0 to Week 8 (+/- 2 weeks). This defines what the study set out to evaluate, but the registry record does not report a single comparative estimate for that outcome.

Accordingly, the record does not establish the direction or magnitude of a difference in leak rate, or how precisely such a difference was estimated. It does not report an effect estimate, confidence interval, or p-value for the primary comparison. This absence should not be interpreted as showing that the strategies had equivalent outcomes, nor as evidence that one strategy was superior. A conclusion about the comparative primary outcome requires results that are not reported in the registry record.

The intervention description combines PINPOINT and SPY Elite imaging. The primary question therefore concerns the combined imaging strategy as recorded, not the independent effect of either device. No device-specific primary outcome results are reported. The study’s listed secondary outcomes and adverse-event summaries offer additional descriptive context, but they do not replace a primary endpoint analysis.

The record reports enrollment of 347 and lists a modified Intent-to-Treat definition. Enrollment is not the same as the number analyzed for the primary endpoint, and the record does not give the mITT count or primary outcome denominators. The trial is listed as terminated, but the reason is not reported. These details limit assessment of completeness and of how closely the reported analysis, if any, followed the intended population.

In general, evidence from one trial is interpreted in light of its design, analysis, precision, and applicability. Here, the design and question can be described, but the primary comparative result is unavailable in the registry record. It is therefore not possible to assess the observed effect, its uncertainty, or whether it would be clinically important. No treatment recommendation follows from the available registry information.

13. Why This Trial Matters Statistically

This study asks a statistically important question about a procedural adjunct: whether intraoperative assessment of colon and rectal tissue perfusion with PINPOINT or SPY Elite, added to standard practice, is associated with a different postoperative anastomotic leak rate than standard practice alone. Randomized allocation is relevant because it is intended to support a fair comparison of strategies, while the parallel design makes the groups the basis for that comparison.

The trial also illustrates why a clear endpoint result matters as much as a clear endpoint definition. The registry record identifies a participant-level event and a follow-up window, and it defines an mITT population. Yet it does not report the comparative estimate, uncertainty interval, or p-value, and it lists no analyses. Without these results, readers cannot judge the size or precision of the primary comparison from the registry record.

It also matters that the intervention group combines two devices. The primary question as described is about the imaging strategy as a group, not a head-to-head comparison of PINPOINT and SPY Elite. Device-specific claims would require device-specific results, which are not reported in the registry record.

Finally, the record distinguishes the primary outcome from the serious adverse-event summaries. Counts of serious events and listed event terms are useful descriptive information, but they do not supply the primary comparative analysis. Keeping those evidence types separate prevents safety listings from being mistaken for an answer to the trial’s main question. This distinction is central to sound statistical interpretation: a study’s design, endpoint, analysis population, and actual comparative result all contribute different pieces of evidence.

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 registry record contains limited detail about trial conduct and analysis. It does not report the randomization method, allocation concealment, baseline characteristics by group, or the reason for termination. Masking is listed as none, but the record does not specify how awareness of assignment may have affected care or outcome assessment. These omissions prevent a fuller appraisal of potential sources of bias.

The intervention group combines PINPOINT and SPY Elite, and device-specific use and outcomes are not reported. The record therefore does not support separate conclusions about either imaging device. It also does not provide a primary outcome definition beyond the endpoint description, so clinical criteria for identifying a leak and any adjudication process are not available.

Although the mITT population is defined, the number meeting that definition and the group-specific primary endpoint denominators are not reported. Missing outcome counts, reasons for missingness, and missing-data methods are also not reported in the registry record. These gaps prevent assessment of how complete the primary endpoint data were or how exclusions and missing observations may have affected the comparison.

The primary outcome is not presented as one comparative analysis, and the registry record lists no analyses. It does not report an effect estimate, confidence interval, p-value, analysis model, adjustment strategy, multiplicity procedure, or statistical analysis plan. The planned sample-size justification and any interim analyses are likewise not reported. The termination status does not resolve these uncertainties, and its reason is not reported in the registry record.

These limitations concern what can be evaluated from this record. They do not establish that the trial was conducted improperly or that its results would favor either group. They do mean that the primary comparison’s magnitude, precision, and robustness cannot be judged using the reported registry information alone.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: A Study Assessing Perfusion Outcomes With PINPOINT® Near Infrared Fluorescence Imaging in Low Anterior Resection — NCT02205307.
• Registry record last updated 2020-06-24; status last verified 2020-06.
• Results first posted 2020-06-24.
• 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.

18. Record Summary

NCT02205307 is a randomized, controlled, parallel, multicenter study listed as terminated. Enrollment is 347; the study start is 2015-01, primary completion is 2017-05, and phase is listed as NA. Masking is listed as none.

The study compares standard surgical practice with PINPOINT or SPY Elite perfusion imaging added during low anterior resection against standard practice alone. The primary endpoint is anastomotic leak rate from Day 0 to Week 8 (+/- 2 weeks), in an mITT population defined by initiation of low anterior resection or at least one ICG injection after randomization.

The registry record does not report a single comparative primary endpoint result, effect estimate, confidence interval, or p-value. It also does not report the reason for termination, the analysis plan, or how missing primary outcome data were handled. Serious and other adverse-event counts are listed separately, but they do not provide the missing primary comparison.