This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record.
1. Trial at a Glance
AKIKI was a randomized, parallel-design clinical trial evaluating two renal replacement therapy strategies in patients with acute kidney injury in the intensive care unit.
| Feature | AKIKI |
|---|---|
| ClinicalTrials.gov identifier | NCT01932190 |
| Title | Artificial Kidney Initiation in Kidney Injury |
| Status | Completed |
| Phase | NA |
| Sponsor | Assistance Publique - Hôpitaux de Paris |
| Condition | Renal Replacement Therapy for Acute Kidney Injury in Intensive Care Unit |
| Allocation | Randomized |
| Masking | None |
2. Clinical Question
Population
Patients with renal replacement therapy for acute kidney injury in the intensive care unit.
Intervention
Early RRT strategy.
Comparator
Delayed RRT strategy.
Primary question
Does timing strategy for renal replacement therapy affect overall survival?
3. Trial Design
Randomization
620 participants
Parallel groups
2 strategies
Intervention
RRT timing
Follow-up
Survival assessment
Endpoint
60-day OS
Early RRT strategy
Procedure intervention arm.
Delayed RRT strategy
Procedure comparator arm.
4. Endpoints
| Endpoint | Definition | Time frame |
|---|---|---|
| Overall survival | The date of randomization to the date of death, regardless of cause. | 60 days |
5. Planned Analysis
The registry identifies overall survival as the primary endpoint measured from randomization until death from any cause. For a time-to-event endpoint such as overall survival, analyses commonly use methods that account for censoring, including Kaplan-Meier estimation, comparison of survival distributions, and model-based estimates such as hazard ratios.
6. Statistical Methodology
Time-to-event analysis
Overall survival is a time-to-event endpoint. Unlike a simple proportion, survival analysis incorporates both observed deaths and participants whose follow-up ends before death is observed. These participants contribute information until their last known follow-up time.
where dᵢ represents events at time points and nᵢ represents individuals at risk immediately before those events.
Hazard ratios
A Cox proportional-hazards model is frequently used for randomized survival comparisons. A hazard ratio summarizes the relative instantaneous event rate between groups over follow-up, but it does not directly represent the probability that an individual patient survives.
Censoring
Patients who remain alive at the end of observation or are lost to follow-up may be censored. Correct interpretation requires that censoring assumptions are considered when interpreting survival estimates.
7. Statistical Methods Explained
Why is overall survival analyzed differently from a binary endpoint?
Overall survival includes both whether an event occurred and when it occurred. Survival methods preserve information from different follow-up durations.
What does randomization contribute statistically?
Random allocation helps balance known and unknown patient characteristics between treatment strategies, allowing differences in outcomes to be attributed more reliably to the assigned strategy.
Why does follow-up duration matter?
A survival endpoint depends on observing events over time. Longer follow-up can provide more information about the durability of differences between groups.
Why are confidence intervals important?
Confidence intervals describe uncertainty around an estimated treatment effect. They are needed to understand the precision of an estimate, not only whether a statistical test crosses a significance threshold.
8. Limitations
- The registry record does not report posted statistical analyses or numerical outcome results.
- Overall survival interpretation depends on follow-up completeness and censoring patterns.
- Randomized comparisons answer the effect of assigned strategies within the enrolled trial population; generalization depends on patient eligibility and clinical setting.
- Without posted analyses, treatment-effect estimates cannot be independently summarized from the registry record.
9. Why This Trial Matters Statistically
| Concept | How it appears in AKIKI |
|---|---|
| Randomization | Comparison of two assigned renal replacement therapy strategies. |
| Parallel design | Two concurrent intervention groups. |
| Time-to-event analysis | Overall survival measured over 60 days. |
| Censoring | Important consideration for survival outcomes. |
| Clinical endpoint interpretation | Separating treatment timing effects from statistical uncertainty. |