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 Low Dose Thymoglobulin to Protect Kidney Function After Liver Transplant (NCT00970073), a randomized na study. The primary outcome is Estimated Glomerular Filtration Rate (eGFR) at 12 Months Post-surgery.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00970073 |
| Phase | NA |
| Condition | Liver Transplantation |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 30 |
| Arms in the primary outcome | 3 |
| Lead sponsor | The Cleveland Clinic |
| Results posted | Yes |
2. Clinical Question
Population
The registry describes a study in people undergoing liver transplantation. The condition is listed as liver transplantation, and the primary endpoint concerns kidney function after surgery. Detailed eligibility criteria, such as restrictions based on baseline kidney function or other clinical characteristics, are not reported in the registry record. The enrollment listed for the trial is 30.
Intervention
The delayed-treatment strategy combined Thymoglobulin, mycophenolate mofetil (MMF), and corticosteroids, with calcineurin inhibitor (CNI) treatment delayed until 10 days after transplant. One group received Thymoglobulin 3mg total on Days 0 and 2, with tacrolimus 3-8 as the trough concentration. The other received Thymoglobulin 4.5mg total and tacrolimus 3-8. The timing of Thymoglobulin for the latter group is not reported in the registry record.
Comparator
The control strategy was early CNI treatment. Tacrolimus 8-12 was initiated within 48 hours after transplant, with MMF and corticosteroids administered within 24 hours after transplant. These are the treatment descriptions in the registry; further details about dose adjustment or adherence are not reported in the registry record.
Primary question
The primary endpoint asks how median estimated glomerular filtration rate (eGFR), measured in mL/min at 12 months after surgery, differed across the delayed-CNI groups and the early-CNI control group. The registry describes postoperative acute kidney injury as reduced eGFR within 12 months. The posted endpoint is a group-level median at 12 months, rather than a reported individual diagnosis of acute kidney injury. The record does not list a formal statistical comparison for this primary endpoint.
3. Trial Design
NCT00970073 is listed as a completed, randomized, parallel-group trial sponsored by The Cleveland Clinic. The registry lists its phase as NA and its masking as none, so participants and study personnel were not masked according to the record. The listed enrollment is 30. The posted primary outcome has three groups, each with 10 participants represented in the endpoint summary: two delayed-CNI groups with different Thymoglobulin regimens and an early-CNI control group.
The study compared a strategy of delaying CNI therapy until 10 days after liver transplantation, with Thymoglobulin, MMF, and corticosteroids, against standard early tacrolimus with MMF and corticosteroids. The first delayed group received Thymoglobulin 3mg total on Days 0 and 2 and tacrolimus 3-8 as the trough concentration. The second received Thymoglobulin 4.5mg total and tacrolimus 3-8. The control group received tacrolimus 8-12 within 48 hours after transplant, with MMF and corticosteroids within 24 hours. The registry does not report the allocation sequence method, concealment procedures, or more detailed treatment-adherence information.
The study start is listed as 2009-08, and primary completion as 2015-06-15. The record reports patient survival and graft survival at 12 months post-transplant, and allograft rejection rates at 30 days, as secondary outcomes. It lists four outcome measures, but the posted results include three secondary outcomes in addition to the primary endpoint. Formal analysis details, including the intended analysis populations and statistical plan, 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 | Delayed CNI Group 1 | Delayed CNI Group 2 | Early CNI / Control Arm |
|---|---|---|---|
| STARTED | 10 | 10 | 10 |
| COMPLETED | 10 | 10 | 10 |
| NOT COMPLETED | 0 | 0 | 0 |
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 | Delayed CNI Group 1 | Delayed CNI Group 2 | Early CNI / Control Arm | Total |
|---|---|---|---|---|---|
| Participants analysed | 10 | 10 | 10 | 30 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 9 | 9 | 10 | 28 |
| Age, Categorical: >=65 years | Participants | 1 | 1 | 0 | 2 |
| Sex: Female, Male: Female | Participants | 2 | 1 | 3 | 6 |
| Sex: Female, Male: Male | Participants | 8 | 9 | 7 | 24 |
| Race and Ethnicity Not Collected | Participants | — | — | — | 0 |
| Region of Enrollment: United States | Participants | 10 | 10 | 10 | 30 |
6. Primary Endpoint
The registry lists the primary outcome as Estimated Glomerular Filtration Rate (eGFR) at 12 Months Post-surgery, measured over 12 Months.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | 90% Confidence Interval |
| Unit | mL/min |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is estimated glomerular filtration rate (eGFR) at 12 months after surgery, reported in mL/min as a median with a 90% confidence interval. eGFR is an estimate of kidney filtration function. The registry describes postoperative acute kidney injury as reduced eGFR within 12 months, making kidney function relevant to the study’s renal-protection question after liver transplantation.
The posted endpoint summarizes eGFR at the 12-month time point for each treatment group. A median describes the middle of the observed group distribution; it does not show the full distribution or how many participants had a particular degree of kidney impairment. The confidence interval conveys uncertainty around the group median under the method used to construct it. The registry does not report the exact eGFR definition, the threshold for reduced eGFR, or whether the analysis used a particular baseline measurement. It also does not report an inferential comparison between groups for this primary endpoint. Thus, the endpoint summaries describe kidney function at the stated time point, but do not by themselves establish a treatment effect or identify the frequency of acute kidney injury.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
At 12 months, the reported median eGFR was 72.0 mL/min in Delayed CNI Group 1, with a 90% confidence interval of 57.7 to 86.3. In Delayed CNI Group 2, the median was 87.8 mL/min, with a 90% confidence interval of 67.3 to 108.3. In the Early CNI / Control Arm, the median was 51.0 mL/min, with a 90% confidence interval of 24.4 to 77.6. These summaries place both delayed-CNI group medians above the control-group median in the posted results. The intervals are broad and overlap, and the registry does not list a formal primary-endpoint comparison or a p-value. The pattern is descriptive, not a demonstrated difference between treatment strategies.
The interval estimates communicate uncertainty as well as the median estimates. Their breadth means that the precise group medians are not pinned down closely by these data. With 10 participants represented in each group’s primary endpoint summary, the estimates should be read cautiously; an individual observation can have substantial influence in a group of this size. The record does not state how missing endpoint values, if any, were handled, so the displayed groups cannot be assumed to represent a particular missing-data strategy.
The posted secondary outcomes provide additional but limited context. At 12 months, patient survival and graft survival show the same broad descriptive ordering as the eGFR medians: the delayed-CNI groups have higher reported counts than the control group. The 30-day rejection summaries do not show that same ordering. These are separate outcomes, each based on small group summaries, and the record lists no reported analyses for them. They should not be combined into a single conclusion about the primary endpoint.
For the binary secondary outcomes, the posted comparisons include unadjusted risk differences and unadjusted p-values. Those comparisons are not adjusted for the multiple outcomes and group contrasts represented in the record. Their uncertainty is considerable, as reflected in the displayed intervals, and the registry does not report a sponsor analysis to supersede or contextualize these calculations. A p-value is not the probability that a treatment works, nor does a value above a conventional threshold establish equivalence. In particular, the absence of a reported statistically significant result would not show that the strategies are the same.
Overall, the primary endpoint summaries are compatible with a potentially favorable descriptive pattern for delayed CNI therapy, but the record does not provide a formal primary comparison or enough precision to draw a firm comparative conclusion. The study results are useful as a record of observed group summaries, not as conclusive evidence that one regimen improves kidney function or other outcomes.
9. Statistical Methods Explained
The main endpoint is a continuous measure summarized by a median. A median identifies the middle value in an ordered set of observations and is less sensitive to extreme observations than an arithmetic mean. It does not describe the spread of all individual measurements, however, and two groups with the same median can have different distributions. The posted record does not include individual eGFR values or another measure of distribution, so the group medians alone cannot show the range or shape of kidney-function outcomes.
The primary endpoint includes 90% confidence intervals. In general, a confidence interval expresses the uncertainty associated with an estimate under the method’s assumptions: intervals that are narrower indicate greater precision, while broader intervals indicate less precision. A confidence interval is not a guarantee that the true value lies within its displayed limits, and it is not a direct probability statement about the value in this particular trial. The posted intervals are broad and overlap. Overlap alone is not a formal test of whether group estimates differ; a direct comparison requires an appropriate analysis of the endpoint and its design. No formal primary-endpoint comparison is listed in the registry record.
The registry reports medians and intervals separately for three groups, rather than a single contrast between each delayed regimen and control for the primary endpoint. That distinction matters: comparing the appearance of separate intervals is not equivalent to estimating a treatment contrast with its own uncertainty. The record does not describe an adjustment for baseline characteristics, an analysis model, or a method for comparing the group medians. It is therefore not possible to determine from the record whether the posted summaries are adjusted or how a formal analysis would have accounted for the randomized design.
For binary outcomes, the posted comparisons express differences in observed event proportions as risk differences. A risk difference is an absolute contrast: it describes how much the observed event proportion in one group differs from that in the comparator group. Positive and negative values indicate opposite directions according to the order of the contrast. The displayed risk-difference intervals represent uncertainty in those unadjusted contrasts. The record does not state their confidence level, so it should not be inferred from the primary endpoint’s 90% intervals.
The unadjusted p-values accompanying secondary comparisons quantify how unusual the observed data, or data more extreme, would be under a specified no-difference model and its assumptions. They do not give the probability that the no-difference model is true. They also do not measure the size or clinical importance of a difference. With limited group sizes and sparse event counts, estimates can be imprecise, and conventional tests may have limited ability to distinguish a difference from chance variation. A non-small p-value is not evidence that groups are equivalent; establishing equivalence or noninferiority would require an appropriate design, margin, and analysis, none of which is reported for these outcomes.
The registry lists no reported analyses for the primary endpoint or the secondary outcomes. The binary comparisons displayed are unadjusted calculations rather than a reported sponsor analysis. They should be treated as descriptive statistical comparisons, not as a substitute for an analysis plan that addresses the randomized design, outcome definitions, missing values, and multiplicity. The record does not report whether analyses were intention-to-treat, per-protocol, or based on another analysis population.
The sample-size illustrations are planning calculations based on observed effects, not observed power and not evidence of the trial’s original design assumptions. The record describes their assumptions as a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect set to a stated fraction of the observed effect. For non-time-to-event outcomes, the figures refer to participants per arm. Such illustrations are sensitive to the observed effect: a planning calculation based on an unstable estimate from a small study may not be a reliable basis for a future trial without external justification. The registry does not report the trial’s own sample-size justification, its planned power, or whether any such calculations informed the original enrollment.
Over-dispersion is a general concern when a statistical model assumes less variation than the data contain. In that situation, standard errors can be too small and uncertainty can be understated. It is not possible to assess or attribute over-dispersion in these results because the registry does not report the primary analysis model, individual-level data, or a variance assessment. More broadly, the record does not report interim analyses, adjustment for multiple testing, missing-data methods, or sensitivity analyses; their use should not be assumed.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one primary endpoint and three secondary outcomes, with comparisons involving two delayed-CNI groups and an early-CNI control group. Considering several endpoints and contrasts increases the opportunity for chance findings. The record does not report a multiplicity strategy, such as a prespecified testing hierarchy or an adjustment to account for multiple comparisons. The secondary p-values are unadjusted, so they should not be read as confirmatory evidence in isolation. Whether multiplicity was addressed in a separate analysis is not reported in the registry record.
Missing-data handling is also not reported. The outcome summaries do not explain whether all randomized participants contributed to each endpoint, how unavailable measurements were handled, or whether any imputation or sensitivity analysis was used. The record does not report reasons for missing values or a comparison of participants with and without observed outcomes. It is therefore not possible to assess whether missingness could have affected the reported summaries.
The analysis populations are not reported. The record does not say whether the results were analyzed according to randomized assignment, treatment received, or another population definition. It also does not report a protocol-defined statistical analysis plan, interim analyses, or the primary endpoint’s comparison model. These omissions limit assessment of whether the displayed results follow the intended analysis and how robust the findings are to alternative assumptions.
Not reporting these procedures does not establish that they were not used; it means they cannot be evaluated from the registry record. The posted estimates and unadjusted comparisons should therefore be interpreted as the available outcome summaries, with uncertainty about the analysis choices behind them.
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 |
|---|---|---|---|
| Delayed CNI Group 1 | 0 | 10 | 0.0% |
| Delayed CNI Group 2 | 1 | 10 | 10.0% |
| Early CNI / Control Arm | 1 | 10 | 10.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Delayed CNI Group 1 | 0 of 10 |
| Delayed CNI Group 2 | 1 of 10 |
| Early CNI / Control Arm | 2 of 10 |
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 |
|---|---|
| Delayed CNI Group 1 | 2 of 10 |
| Delayed CNI Group 2 | 5 of 10 |
| Early CNI / Control Arm | 4 of 10 |
Most frequent serious adverse event terms
| Event term | Organ system | Delayed CNI Group 1 | Delayed CNI Group 2 | Early CNI / Control Arm |
|---|---|---|---|---|
| Metastatic Lung Cancer | Respiratory, thoracic and mediastinal disorders | 0 of 10 | 1 of 10 | 0 of 10 |
| Graft vs Host Disease | Immune system disorders | 0 of 10 | 0 of 10 | 1 of 10 |
| Heart Failure | Cardiac disorders | 0 of 10 | 0 of 10 | 1 of 10 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Delayed CNI Group 1 | Delayed CNI Group 2 | Early CNI / Control Arm |
|---|---|---|---|---|
| HCV recurrence | Infections and infestations | 2 of 10 | 5 of 10 | 4 of 10 |
Serious events with the highest arm-level rate: metastatic lung cancer (10.0%), graft vs host disease (10.0%), heart failure (10.0%).
The adverse-event summary reports participants at risk and participants affected in each group. For serious adverse events, the listed affected counts are 0 in Delayed CNI Group 1, 1 in Delayed CNI Group 2, and 1 in the Early CNI / Control Arm; 10 participants are listed at risk in each group. The record also identifies Metastatic Lung Cancer, Graft vs Host Disease, and Heart Failure among the top serious-event terms, each reported as 10.0%. It does not specify in this summary which group or groups contributed each term.
For other adverse events, the affected counts are 2, 5, and 4 in Delayed CNI Group 1, Delayed CNI Group 2, and the control group, respectively. Death counts are listed as 0, 1, and 2 in those same groups. These counts are descriptive; they do not establish that treatment caused an event or that one strategy has a different safety profile. With the small group summaries, event counts can be unstable. The registry record does not provide event narratives, timing, severity grading beyond the serious-event designation, attribution, or a detailed account of how adverse events were collected. The listed terms and counts should not be interpreted as a complete clinical safety assessment.
12. What the Result Does, and Does Not, Mean
The posted primary results show higher median eGFR values in both delayed-CNI groups than in the early-CNI control group at 12 months. The confidence intervals indicate uncertainty around those estimates, and the registry does not report a formal comparison for the primary endpoint. The results therefore describe an observed pattern, but do not establish that delaying CNI therapy caused better kidney function or reduced acute kidney injury.
The endpoint is a group-level eGFR summary at a specified time point. It is not, by itself, a measure of every aspect of kidney health, a report of individual clinical outcomes, or proof that a participant did or did not experience acute kidney injury. The registry’s description links acute kidney injury to reduced eGFR within 12 months, but does not specify a threshold or report the number of participants meeting a diagnostic definition.
The secondary survival, graft-survival, rejection, and safety summaries provide additional observations but are not definitive treatment comparisons. The unadjusted secondary results do not account for the full set of outcomes and contrasts, and the record does not provide a multiplicity plan or reported sponsor analyses. They cannot independently establish efficacy or safety.
These findings also do not show that the treatment strategies are equivalent. A lack of a reported formal difference is not evidence of equivalence, and the registry does not report a noninferiority or equivalence framework. The study’s group summaries can inform interpretation of what was observed in this trial, while leaving substantial uncertainty about the comparative effects, precision, generalizability, and safety of the regimens.
13. Why This Trial Matters Statistically
This trial is statistically notable for comparing a renal-protection strategy that delays CNI therapy with an early-CNI approach after liver transplantation, while reporting three treatment groups rather than a single intervention group and control group. The primary outcome is a continuous kidney-function measure, summarized by group medians and 90% confidence intervals. The displayed estimates make the descriptive pattern easy to see, but the absence of a reported formal primary comparison is an important limit on inference.
The study also illustrates the challenges of interpreting small randomized groups. Each primary endpoint summary represents 10 participants, so the precision of the estimates and the stability of individual event counts deserve attention. This does not invalidate the observations; it means that uncertainty should remain central to interpretation. The secondary outcomes add clinically relevant dimensions, but multiple unadjusted comparisons can make isolated apparent patterns less persuasive.
Finally, the record distinguishes between results and planning. Its sample-size illustrations use observed effects and stated assumptions; they are not evidence of observed power or of the original design justification. The registry does not report the original statistical plan, analysis populations, or missing-data methods. For biostatisticians and clinical researchers, the trial underscores why treatment contrasts, uncertainty, multiplicity, and analysis transparency matter alongside the numerical outcome summaries.
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.
Several limitations specific to this trial constrain interpretation. The primary endpoint summaries represent 10 participants in each group, and the registry does not report individual-level eGFR values, a measure of distribution, or a formal comparison between the groups. The intervals are broad, so the medians are not estimated with high precision. The registry also does not state how reduced eGFR was defined or how missing 12-month measurements, if any, were handled.
The intervention groups differ in Thymoglobulin dose, and the record describes both as delayed-CNI regimens. This means that the group summaries do not isolate the effect of delaying CNI from the effect of the Thymoglobulin regimen. The timing of Thymoglobulin in Delayed CNI Group 2 is not reported in the registry record. Further details on adherence, dose modification, and treatment received are also not reported.
The record lists secondary outcomes but no reported analyses. The posted binary comparisons are unadjusted, and no multiplicity strategy, analysis populations, or missing-data approach is reported. Sparse events and limited group sizes make those comparisons imprecise. The record does not provide eligibility criteria, baseline characteristics, or enough detail to assess balance between randomized groups or the applicability of the results to other transplant populations.
Finally, the study is listed as open-label, and the registry does not report details about outcome assessment procedures. The record does not include a formal safety analysis or an account of adverse-event attribution. These limitations do not negate the posted observations, but they restrict how confidently those observations can be interpreted as comparative effects.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Low Dose Thymoglobulin to Protect Kidney Function After Liver Transplant — NCT00970073.
- Registry record last updated 2018-10-09; status last verified 2018-09.
- Results first posted 2018-10-09.
- 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
NCT00970073 is a completed, randomized, open-label, parallel-group study sponsored by The Cleveland Clinic. It evaluated delayed CNI therapy with Thymoglobulin, MMF, and corticosteroids against early tacrolimus with MMF and corticosteroids after liver transplantation. The listed enrollment is 30, and the primary outcome is median eGFR in mL/min at 12 months after surgery, reported with 90% confidence intervals.
The posted medians are higher in both delayed-CNI groups than in the early-CNI control group, but the registry does not report a formal primary comparison. Secondary outcomes include patient survival, graft survival, and allograft rejection; their comparisons are unadjusted and should be read cautiously. The registry does not report the statistical analysis plan, analysis populations, multiplicity approach, or missing-data methods.