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 Assessment of Urinary NGAL to Predict AKI in Children Receiving Multiple Nephrotoxic Medications (NCT03527160), a registered phase not stated study. The primary outcome is Number of Patients With Nephrotoxic Medication Associated AKI Detected by Urinary NGAL.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03527160 |
| Phase | Phase not stated |
| Condition | Acute Kidney Injury, Nephrotoxicity |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 134 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Children's Hospital Medical Center, Cincinnati |
| Results posted | Yes |
2. Clinical Question
Population
Children exposed to multiple nephrotoxic medications are the population of interest. The registry record gives enrollment as 134, but does not report further eligibility details or a fuller description of the analyzed population.
Intervention
The study examines urinary neutrophil gelatinase-associated lipocalin, abbreviated NGAL, as a way to detect nephrotoxic medication-associated acute kidney injury. Its brief summary also describes a hypothesis about bedside urine testing in high-risk exposed patients.
Comparator
The brief summary frames the bedside test in relation to urinary NGAL measured on a clinical platform. It also notes that serum creatinine monitoring is currently available for monitoring this form of kidney injury. The registry does not describe a randomized comparison or identify a like-for-like control group.
Primary question
The primary endpoint is the number of participants with nephrotoxic medication-associated acute kidney injury first detected by a rise in urinary NGAL during a timeframe of 9 Days. The record does not report the observed endpoint count, or estimates of the sensitivity or reliability of either testing approach.
The registry's stated hypotheses are that urine NGAL is highly sensitive for detecting nephrotoxic medication-associated acute kidney injury and that bedside urine testing is adequate and reliable compared with urinary NGAL measured on the clinical platform. These are research questions, not reported findings. The record describes the outcome definition and the planned question, but it does not establish whether the hypotheses were supported.
The study summary gives a rationale: it describes nephrotoxic medication exposure as a commonly cited cause of acute kidney injury in hospitalized children and states that prior work at Cincinnati Children's Medical Center found exposure potentially modifiable. The summary also states that this exposure is the primary cause of acute kidney injury in 16% of cases. These statements provide context from the study summary; they are not results of the current study.
3. Trial Design
The registry lists the study as completed, with a start date of 2018-04-23 and a primary completion date of 2019-05-31. Enrollment is recorded as 134. The sponsor is Children's Hospital Medical Center, Cincinnati. These administrative details do not describe how participants were selected, followed, or assigned to any testing strategy.
The named group in the adverse-event record is NINJA. The registry does not state an allocation method, and the record identifies this as not being a randomized comparison. Its groups therefore should not be interpreted as like-for-like control arms. Further design details, including whether participants were enrolled consecutively or how testing was scheduled, are not reported in the registry record.
The primary outcome is a count of participants with nephrotoxic medication-associated acute kidney injury detected by urinary NGAL. The record gives a timeframe of 9 Days and defines acute kidney injury through a serum creatinine rise: a 50% rise over baseline or a 0.3 mg/dL rise within 48 hours. The registry also lists a secondary outcome concerning point-of-care NGAL reliability compared with clinical urinary NGAL.
The registry does not describe a prespecified statistical analysis, analysis population, or sample-size justification. It provides no primary outcome result or reliability estimate. The stated planning illustration assumptions are not details of the study design: they describe a calculation based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They should not be read as evidence that this study used those design features.
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 | NINJA |
|---|---|
| STARTED | 134 |
| COMPLETED | 113 |
| NOT COMPLETED | 21 |
Reasons for not completing this period:
| Reason | NINJA |
|---|---|
| No urine collected | 13 |
| No clinical serum creatinine collected | 6 |
| Did not meet inclusion | 2 |
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.
Population: Participants separated into these two groups during the analysis, depending on whether they developed AKI per KDIGO serum creatinine guidelines during the course of their participation in the study.
| Characteristic | Unit | Any AKI | No AKI | Total |
|---|---|---|---|---|
| Participants analysed | 27 | 86 | 113 | |
| Age, Continuous | years | 16.2 (12.1 to 19.1) | 12.0 (5.9 to 18.0) | 13.2 (6.7 to 18.2) |
| Sex: Female, Male: Female | Participants | 7 | 45 | 52 |
| Sex: Female, Male: Male | Participants | 20 | 41 | 61 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 | 3 | 3 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 27 | 83 | 110 |
| 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 | 2 | 2 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 3 | 12 | 15 |
| Race (NIH/OMB): White | Participants | 24 | 66 | 90 |
| Race (NIH/OMB): More than one race | Participants | 0 | 1 | 1 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 5 | 5 |
| Weight | kilograms | 47.1 (32.5 to 66.3) | 39.9 (18.0 to 53.0) | 42.3 (21.0 to 56.2) |
6. Primary Endpoint
The registry lists the primary outcome as Number of Patients With Nephrotoxic Medication Associated AKI Detected by Urinary NGAL, measured over 9 Days.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is a count: the number of participants with nephrotoxic medication-associated acute kidney injury detected by a rise in urinary NGAL. The registry specifies a timeframe of 9 Days. It defines acute kidney injury as either a 50% rise in serum creatinine over baseline or a 0.3 mg/dL rise within 48 hours. The endpoint description says urinary NGAL is the first means of detection.
A count of participants with an event can describe how many people met the endpoint in the recorded group. By itself, it does not quantify how accurately a test identifies all cases. Assessing sensitivity would also require information about participants who did and did not meet the acute kidney injury definition, along with the test results for those participants. The registry record does not report those details or a sensitivity estimate.
The endpoint addresses the study's stated question about urinary NGAL as a detection measure. It is not itself a complete measure of test performance, and the registry does not report an observed endpoint count with which to judge the result. The secondary outcome concerning point-of-care NGAL reliability compared with clinical urinary NGAL is listed, but its result and measurement method are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The record establishes the study's topic, endpoint definition, timeframe, and stated rationale. It does not report the primary outcome count. Consequently, the posted record cannot show how many participants met the endpoint, how frequently urinary NGAL first detected acute kidney injury, or how closely bedside testing agreed with clinical-platform urinary NGAL.
The endpoint is a participant count rather than a reported estimate of sensitivity. These quantities answer different questions. A count describes the number of people meeting a definition in a specified group. Sensitivity describes the proportion of people with the target condition who test positive. To estimate it, the results would need to show the relevant test classifications alongside the reference classification. Those data are not reported in the registry record.
The outcome definition uses serum creatinine change, while urinary NGAL is described as the first means of detection. That distinction matters when interpreting the endpoint: the record describes a rule for defining acute kidney injury and a test used to detect it, but does not provide the participant-level or summary results needed to evaluate their relationship. It also does not report a comparison estimate, confidence interval, or test-performance statistics.
The brief summary states two hypotheses, including high sensitivity for urinary NGAL and adequacy and reliability of bedside testing compared with clinical-platform urinary NGAL. Those statements should be read as hypotheses rather than conclusions. The record lists a secondary reliability outcome, but gives no reliability result. There is therefore no posted evidence in this record to quantify agreement, precision, or the extent of any difference between the testing approaches.
The completion status and enrollment count do not substitute for outcome reporting. Enrollment is recorded as 134, but the record does not specify the number analyzed for the primary endpoint, whether all enrolled participants contributed data, or how missing observations were handled. The safety figures are separate from the primary endpoint and cannot establish urinary NGAL performance.
Planning calculations based on a stated fraction of an observed effect are planning illustrations, not observed power. Because the registry record does not report the outcome result or observed effect, such illustrations cannot be treated as a summary of the trial's observed evidence. The record also does not report whether any sponsor analysis supersedes a recalculation. Overall, the registry describes a clinically motivated question but does not provide enough outcome information to determine what the study found.
9. Statistical Methods Explained
What does a participant count tell the reader?
The primary endpoint is a count of participants who met the acute kidney injury definition and whose condition was first detected by urinary NGAL. A count is a descriptive summary. To interpret it, a reader would also need a clear denominator: the number of participants assessed under the endpoint definition. The enrollment figure is 134, but the registry does not state that this is the endpoint denominator, nor does it report the observed count. The count and its denominator are both needed to describe the event frequency in the analyzed group.
A count also differs from an estimate of diagnostic accuracy. Sensitivity concerns the ability of a test to identify people who have the target condition. Specificity concerns the ability to identify people who do not have it. Agreement compares classifications from testing methods. These are general statistical concepts; the registry does not report sensitivity, specificity, or agreement estimates for this study. A count alone cannot supply those results.
How should the definition of acute kidney injury be understood?
The registry defines the endpoint condition as a 50% rise in serum creatinine over baseline or a 0.3 mg/dL rise within 48 hours. This is the stated outcome rule, not a statistical analysis method. The description also says that a rise in urinary NGAL first detects the event. For a reader to evaluate how those criteria were applied, the record would need to explain the timing and availability of measurements and how cases were classified. Those procedural details are not reported in the registry record.
In general, a threshold-based definition turns a continuous measurement into a classification. That can make an outcome easier to summarize as an event count, but results may depend on the threshold and measurement schedule. This general point does not establish that the study used any particular schedule beyond the timeframe and definition stated in the registry.
What does uncertainty around an estimate mean?
In general, a confidence interval describes the range of values reasonably compatible with the data under the assumptions of the analysis. A narrow interval indicates greater precision than a wide interval, while neither interval by itself establishes that a finding is clinically important. The registry record does not report a confidence interval for the primary endpoint or for the secondary reliability outcome. Without an observed estimate and its uncertainty, the precision of the study result cannot be assessed.
A p-value, in general, describes how surprising data at least as extreme as those observed would be under a specified statistical model and null hypothesis. It does not measure the size or clinical importance of an effect. No p-value or hypothesis-test result is reported in the registry record. It would therefore be inappropriate to infer statistical significance or lack of significance from the study's completion status, enrollment, or safety counts.
What is the role of a planning illustration?
The record describes sample-size planning assumptions based on the observed effect: a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect to detect expressed as a stated fraction of the observed effect. These are assumptions for a planning illustration, not evidence that the trial was designed or conducted with equal allocation or a two-arm randomized comparison. The record says this is not a randomized comparison and does not state an allocation method.
A planning illustration asks how much information might be needed under specified assumptions. It is not an observed trial result and is not observed power. Observed power is not a substitute for reporting the effect estimate and its uncertainty. Here, the registry record does not report the primary outcome result or the observed effect needed to interpret the illustration in relation to the trial's findings. No planning sample-size values are stated in the registry record.
What can be concluded about the analysis?
The registry lists two outcome measures and records zero analyses. It does not report a statistical analysis plan, a model, adjustment variables, confidence intervals, or an analysis population. Those omissions mean the statistical approach cannot be reconstructed from the registry record. The secondary reliability outcome is named, but the record does not explain how reliability was measured or analyzed.
Over-dispersion is a general concern when observed count variation is greater than a model expects. It can make standard errors too small if a model assumes less variability than the data contain. This is a general statistical consideration, not a claim that the current study used a count model or had over-dispersed data. The registry does not report a model or the data needed to assess that issue.
In short, the methods information supports interpretation of the endpoint definition and the stated planning assumptions, but not a reconstruction of the analysis. Any stronger conclusion about diagnostic performance, statistical significance, or precision would require results and methods not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists two outcome measures: the primary count of participants with nephrotoxic medication-associated acute kidney injury detected by urinary NGAL, and a secondary outcome concerning point-of-care NGAL reliability compared with clinical urinary NGAL. It does not report how the outcomes were prioritized in the analysis beyond their primary and secondary labels, or how multiple statistical tests were handled. A multiplicity adjustment or testing hierarchy is not reported in the registry record.
Multiplicity matters in general when several hypotheses are tested, because repeated testing can increase the chance of a positive finding by chance. Whether and how this issue affected the study cannot be assessed without the analysis plan and results. The registry records zero analyses, so no outcome-specific inferential analysis is available to review.
Missing-data procedures are also not reported in the registry record. It does not state whether outcome measurements were missing, how missing observations were treated, or whether any sensitivity analyses were conducted. Enrollment is recorded as 134, but the number contributing data to the primary outcome is not reported. It should not be assumed that enrollment equals the analysis population.
The record does not identify an intention-to-treat, per-protocol, or other analysis population. Since the study is not described as a randomized comparison and the allocation method is not stated, those labels should not be applied by inference. The population used for the primary and secondary outcome analyses is not reported in the registry record.
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 |
|---|---|---|---|
| NINJA | 0 | 113 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| NINJA | 0 of 113 |
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 |
|---|---|
| NINJA | 0 of 113 |
The adverse-event record lists the NINJA group with 113 participants at risk, 0 participants affected by serious adverse events, and 0 deaths. No serious adverse-event terms are listed. These are the figures recorded for that group; they are separate from the primary urinary NGAL endpoint and do not measure diagnostic performance.
A zero recorded count means the registry reports no events in that category for the group as recorded. It does not, by itself, establish that no adverse events of any kind occurred, that all safety information was collected, or that a testing strategy caused no harm. The record does not provide additional detail on safety-event ascertainment, follow-up completeness, or the relationship between the group at risk and the enrollment figure.
Safety counts should be interpreted alongside the population monitored, the event definitions, and the duration and completeness of follow-up. The registry provides the timeframe of 9 Days for the primary endpoint, but does not state that this is the safety follow-up period. No broader safety conclusion can be drawn from these figures alone.
12. What the Result Does, and Does Not, Mean
The registry record establishes that the study addressed urinary NGAL as a possible way to detect acute kidney injury associated with nephrotoxic medication exposure in children. It defines the primary endpoint, gives its timeframe, and describes hypotheses about urinary NGAL sensitivity and bedside-test reliability. These details clarify the intended research question.
The record does not report the primary endpoint count, test-performance estimates, reliability results, or inferential analyses. It therefore does not show whether urinary NGAL detected acute kidney injury in the study, how often it did so, or how bedside results compared with clinical-platform measurements. The hypotheses cannot be treated as findings, and no conclusion about test accuracy can be drawn from the endpoint description alone.
The endpoint uses a serum creatinine rise to define acute kidney injury and urinary NGAL as the first means of detection. Without the observed classifications and measurement details, the record does not allow assessment of how well the detection measure corresponded to the outcome definition. Nor does it establish that bedside testing is adequate or reliable.
The safety figures record 0 serious adverse events and 0 deaths in the NINJA group, among 113 participants at risk. These figures are limited to the recorded categories and do not answer the primary research question. They should not be interpreted as a complete assessment of all possible safety events.
The most defensible reading is that this registry record documents a relevant question and its planned outcome definitions, while leaving the central outcome evidence unavailable. The completed status and enrollment count do not fill that gap. Conclusions about effectiveness, diagnostic performance, precision, or comparative benefit are not reported in the registry record.
13. Why This Trial Matters Statistically
This study's statistical question is more specific than whether an event occurred. It asks whether urinary NGAL can identify nephrotoxic medication-associated acute kidney injury and whether bedside testing corresponds adequately and reliably with clinical-platform urinary NGAL. Those questions require diagnostic or agreement results, not merely a participant count. Separating the endpoint definition from test-performance measures helps prevent a count from being mistaken for sensitivity or reliability.
The registry's endpoint description also makes the reference definition important. Acute kidney injury is defined by serum creatinine change, while urinary NGAL is described as first detecting the event. Clear reporting of how measurements are timed and how cases are classified would help readers assess the relation between an early detection signal and the defined outcome. Those details and the resulting analyses are not reported in the registry record.
The study summary presents a rationale centered on potentially modifiable medication exposure and an avoidable adverse safety event. That framing explains why an early detection measure is of interest, but it is not evidence that the test achieved the proposed purpose. Statistical interpretation depends on observed data, denominators, and uncertainty estimates, none of which are reported for the primary outcome.
The record is also a useful example of why registry status, enrollment, outcome definitions, and outcome findings are distinct pieces of information. A completed study with enrollment recorded as 134 can still have no posted primary result in the registry record. Readers need the actual outcome analysis to judge its magnitude and precision; the stated hypotheses and planning assumptions cannot replace it.
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 central limitation for interpretation is that the registry record does not report the primary endpoint result. It also omits the observed effect, denominator for the endpoint, and test-performance estimates. As a result, the main question about urinary NGAL detection cannot be answered from the posted record.
The registry does not report results for the secondary point-of-care reliability outcome. It does not describe the reliability metric, how testing methods were compared, or the uncertainty around any comparison. The stated hypotheses therefore remain hypotheses in this record.
Design and analysis details are sparse. Allocation is not stated, the record identifies the study as not a randomized comparison, and no like-for-like control comparison is described. Participant eligibility, measurement schedules, analysis populations, missing-data handling, and statistical models are not reported in the registry record. These gaps limit assessment of selection, measurement, and analysis issues.
The primary endpoint definition is stated, but operational detail about applying it is not reported. In particular, the record does not describe how urinary NGAL results were classified, how the timing of measurements was handled, or how the creatinine-based definition was applied when measurements were unavailable. These are uncertainties in the documentation, not evidence that any particular problem occurred.
The safety record gives figures for serious adverse events and deaths but does not report broader safety ascertainment details or establish the safety follow-up period. The NINJA group has 113 participants at risk, while overall enrollment is recorded as 134; the relationship between those figures is not explained. The registry record does not report whether the safety and efficacy populations differed or why.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Assessment of Urinary NGAL to Predict AKI in Children Receiving Multiple Nephrotoxic Medications — NCT03527160.
- Registry record last updated 2021-10-05; status last verified 2021-09.
- Results first posted 2021-06-18.
- 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 identifies a completed study titled “Assessment of Urinary NGAL to Predict AKI in Children Receiving Multiple Nephrotoxic Medications,” sponsored by Children's Hospital Medical Center, Cincinnati. Enrollment is recorded as 134. The start date is 2018-04-23, and the primary completion date is 2019-05-31.
The primary outcome is a participant count for nephrotoxic medication-associated acute kidney injury first detected by urinary NGAL, over a timeframe of 9 Days. The condition is defined by a 50% rise in serum creatinine over baseline or a 0.3 mg/dL rise within 48 hours. A secondary outcome concerns point-of-care NGAL reliability compared with clinical urinary NGAL.
The record states hypotheses about sensitivity and bedside-test reliability, but does not report outcome results, test-performance estimates, or statistical analyses. It identifies no randomized comparison and does not state allocation. The adverse-event record reports 0 serious adverse events and 0 deaths for the NINJA group, with 113 participants at risk.