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 Calcium Aluminosilicate Anti-Diarrheal in Treating and Preventing Diarrhea in Patients With Metastatic Colorectal Cancer Receiving Irinotecan (NCT00748215), a randomized phase 2 study. The primary outcome is Number of Participants With Grade 3/4 Diarrhea.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00748215 |
| Phase | Phase 2 |
| Condition | Chemotherapeutic Agent Toxicity, Colorectal Cancer, Diarrhea |
| Allocation | Randomized |
| Design model | Single Group |
| Masking | Triple |
| Enrollment | 100 |
| Arms in the primary outcome | n/a |
| Lead sponsor | M.D. Anderson Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
Patients with metastatic colorectal cancer receiving irinotecan. The primary outcome description refers to patients who experienced any diarrhea or grade 3/4 diarrhea during the intervention period, but the registry record does not explain how that population description was used in the analysis.
Intervention
Oral calcium aluminosilicate anti-diarrheal, abbreviated CASAD, taken 4 times daily for 6 weeks in the absence of disease progression or unacceptable toxicity. Participants who developed grade 3 or 4 diarrhea could receive CASAD for an additional 6 weeks.
Comparator
Oral placebo, taken 4 times daily for 6 weeks in the absence of disease progression or unacceptable toxicity. Participants who developed grade 3 or 4 diarrhea could then receive CASAD for 6 weeks.
Primary question
Did CASAD reduce the occurrence of grade 3/4 diarrhea during the first 6 weeks compared with placebo? The registry record describes this as a prevention question. It does not report the arm-specific primary outcome counts or an estimate of the difference between arms, so the comparative result cannot be assessed from this record.
The study was described as a randomized, double-blind comparison in its official title, and the registry lists triple masking. It was a phase II trial in patients with metastatic colorectal cancer receiving irinotecan. The registry rationale says CASAD may help treat and prevent irinotecan-associated diarrhea, while also stating that whether it is more effective than placebo was not known.
The intervention descriptions include a treatment pathway after grade 3 or 4 diarrhea: participants in the placebo arm could then receive CASAD, while participants in the CASAD arm could continue it for an additional 6 weeks. The primary outcome timeframe, however, is the first 6 weeks from baseline during the initial intervention. The registry record does not report results for the later treatment period or explain how it relates to the primary comparison.
3. Trial Design
This was a phase II study with randomized allocation and a placebo comparator. The registry lists the masking as triple, while the official title describes the study as double blind. The registry record does not identify which people were masked or explain the difference in those descriptions. It lists the study model as single-group, which does not readily align with the described randomized comparison between CASAD and placebo; the record does not clarify this classification.
The registry reports enrollment of 100 and says participants were randomized equally between the two arms. CASAD and placebo were each taken orally 4 times daily for 6 weeks, unless disease progression or unacceptable toxicity occurred. For participants who developed grade 3 or 4 diarrhea, the arm descriptions specify a further 6 weeks of CASAD, with the second period differing according to initial assignment.
The primary timeframe was the first 6 weeks from baseline in the initial intervention. The listed primary outcome was the number of participants with grade 3/4 diarrhea. The outcome description also states that Bayesian futility monitoring was used, with a recommendation to stop for futility if it became clear that CASAD was not better than placebo. The monitoring schedule, statistical decision threshold, prior assumptions, and any stopping decision are not reported in the registry record.
The study status is completed. The registry lists a start date of 2009-02-04 and a primary completion date of 2014-08-12. These dates do not supply information about the timing or completeness of outcome reporting. Arm-specific primary outcome counts, an effect estimate, uncertainty intervals, and a test result are not reported in the registry record. Thus, the design can be described, but the primary comparative finding cannot be reconstructed from the registry information.
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.
Before assignment: Of the original 100 patients enrolled and randomized to the 6 week intervention period, 39 patients would go on to take open label CASAD; 22 patients from the CASAD arm and 17 patients from the placebo arm. These patients were added as a Milestone on the Participant Flow sheet. 8 patients received open label for \<21 days; 31 patients received open label CASAD for \>21 days.
Overall Study
| Stage | Arm I: Calcium Aluminosilicate Anti-Diarrheal (CASAD) | Arm II: Placebo |
|---|---|---|
| STARTED | 50 | 50 |
| Open Label CASAD After Initial 6 Weeks Intervention | 22 | 17 |
| COMPLETED | 41 | 32 |
| NOT COMPLETED | 9 | 18 |
Reasons for not completing this period:
| Reason | Arm I: Calcium Aluminosilicate Anti-Diarrheal (CASAD) | Arm II: Placebo |
|---|---|---|
| Withdrawal by Subject | 7 | 7 |
| Treatment change | 2 | 1 |
| Change in patient condition | 0 | 3 |
| Non-compliant | 0 | 2 |
| Adverse Event | 0 | 5 |
Analysis population for the primary outcome, as defined in the registry: Patients who experienced any diarrhea during the intervention period and patients who experienced Grade 3/4 diarrhea during the intervention period.
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 | Arm I: Calcium Aluminosilicate Anti-Diarrheal (CASAD) | Arm II: Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 50 | 50 | 100 | |
| Age, Continuous | Years | 57 (20 to 83) | 56 (26 to 81) | 56.5 (20 to 81) |
| Sex: Female, Male: Female | Participants | 21 | 25 | 46 |
| Sex: Female, Male: Male | Participants | 29 | 25 | 54 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 5 | 6 | 11 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 45 | 44 | 89 |
| 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 | 1 | 0 | 1 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 7 | 9 | 16 |
| Race (NIH/OMB): White | Participants | 42 | 41 | 83 |
| 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 | 50 | 50 | 100 |
| Baseline Bowel Assessment (BBA): < 1 Per Day | Participants | 7 | 6 | 13 |
| Baseline Bowel Assessment (BBA): < 1 -3 Per Day | Participants | 7 | 3 | 10 |
| Baseline Bowel Assessment (BBA): < >3 Per Day | Participants | 27 | 34 | 61 |
| Baseline Bowel Assessment (BBA): Other | Participants | 3 | 3 | 6 |
| Baseline Ostomy Bowel Assessment (BOBA): 2-3 times | Participants | 3 | 3 | 6 |
| Baseline Ostomy Bowel Assessment (BOBA): 4-6 times | Participants | 2 | 0 | 2 |
| Baseline Ostomy Bowel Assessment (BOBA): >6 times | Participants | 0 | 0 | 0 |
| Baseline Ostomy Bowel Assessment (BOBA): Other | Participants | 2 | 1 | 3 |
| Baseline Bowel Assessment (BBA): No | Participants | 7 | 6 | 13 |
| Baseline Bowel Assessment (BBA): Yes, some | Participants | 24 | 32 | 56 |
| Baseline Bowel Assessment (BBA): Yes, significant | Participants | 11 | 8 | 19 |
| Baseline Bowel Assessment (BBA): Not answered | Participants | 2 | 0 | 2 |
| Baseline Bowel Assessment (BBA): Hard difficult to pass | Participants | 8 | 9 | 17 |
| Baseline Bowel Assessment (BBA): Well-formed, easy to pass | Participants | 4 | 2 | 6 |
| Baseline Bowel Assessment (BBA): Loose | Participants | 25 | 29 | 54 |
| Baseline Bowel Assessment (BBA): Very loose and watery | Participants | 7 | 6 | 13 |
| Baseline Bowel Assessment (BBA): Not answered | Participants | 0 | 3 | 3 |
| Baseline Bowel Assessment (BBA): 1/4 Full | Participants | 0 | 1 | 1 |
| Baseline Bowel Assessment (BBA): 1/3 Full (recommended) | Participants | 4 | 1 | 5 |
| Baseline Bowel Assessment (BBA): 1/2 Full | Participants | 1 | 1 | 2 |
| Baseline Bowel Assessment (BBA): Other | Participants | 1 | 0 | 1 |
| Baseline Ostomy Bowel Assessment (BOBA): Does not measure output | Participants | 6 | 4 | 10 |
| Baseline Ostomy Bowel Assessment (BOBA): <200 ml/day | Participants | 0 | 0 | 0 |
| Baseline Ostomy Bowel Assessment (BOBA): 200-600 ml/day (typical) | Participants | 0 | 0 | 0 |
| Baseline Ostomy Bowel Assessment (BOBA): 600-1000 ml/day | Participants | 0 | 0 | 0 |
| Baseline Ostomy Bowel Assessment (BOBA): >1000 ml/day | Participants | 0 | 0 | 0 |
| Baseline Ostomy Bowel Assessment (BOBA): No | Participants | 4 | 4 | 8 |
| Baseline Ostomy Bowel Assessment (BOBA): Yes, some | Participants | 1 | 0 | 1 |
| Baseline Ostomy Bowel Assessment (BOBA): Yes, significant | Participants | 1 | 0 | 1 |
| Baseline Ostomy Bowel Assessment (BOBA): Well-formed, easy to pass | Participants | 0 | 0 | 0 |
| Baseline Ostomy Bowel Assessment (BOBA): Semi-formed (peanut butter consistency) | Participants | 1 | 3 | 4 |
| Baseline Ostomy Bowel Assessment (BOBA): Loose (pudding, cake batter consistency) | Participants | 2 | 1 | 3 |
| Baseline Ostomy Bowel Assessment (BOBA): Very loose and watery | Participants | 3 | 0 | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants With Grade 3/4 Diarrhea, measured over First 6 weeks from baseline in initial intervention with CASAD or PLACEBO.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with grade 3/4 diarrhea during the first 6 weeks from baseline in the initial CASAD or placebo intervention. It is a binary participant-level outcome: each participant either met the stated grade threshold during that timeframe or did not. The registry labels the measure as a count of participants.
Severe diarrhea is the event the trial was intended to prevent, so counting participants who experienced it gives a direct way to compare the occurrence of the specified complication between randomized arms. Restricting the primary timeframe to the initial 6 weeks also distinguishes the comparison of the initial assigned interventions from the later treatment pathway, in which participants could receive CASAD after developing grade 3 or 4 diarrhea.
That distinction matters for interpretation. A count for the initial period would address the stated prevention question; it would not by itself describe the effect of later CASAD treatment, the duration or recurrence of diarrhea, or all diarrhea of any grade. The registry record does not report arm-specific primary endpoint counts, the number of participants included in the endpoint analysis, or a comparative estimate. It also describes the outcome population in terms of participants experiencing any diarrhea and participants experiencing grade 3/4 diarrhea, without explaining the analysis population or denominator. These details are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a clinically specific primary question: whether CASAD, compared with placebo, prevented grade 3/4 diarrhea during the first 6 weeks of initial intervention. It reports that enrollment was 100 and that randomization was equal between arms, but it does not give the primary endpoint count for either arm. There is no posted comparative estimate, confidence interval, or primary-outcome test result in the record. Consequently, the registry information does not establish the direction or precision of the primary comparison.
The adverse-event information is separate from that missing primary result. Serious adverse events affected 4 participants in the CASAD arm and 9 in the placebo arm; 50 participants were listed at risk in each arm. Deaths were recorded for 1 participant in the CASAD arm and 0 in the placebo arm. These counts describe events in the registry's safety reporting and should not be treated as the missing grade 3/4 diarrhea endpoint. They also do not, on their own, establish that an event was caused by the assigned intervention.
In general, an estimate comparing randomized groups is more informative when accompanied by an uncertainty interval. A confidence interval describes a range of effect estimates compatible with the data and analysis assumptions; wider intervals indicate less precision. Because the primary counts and interval are not reported in the registry record, it is not possible to assess the magnitude, direction, or precision of any primary effect. A p-value or claim of statistical significance cannot be inferred from the study design or the safety counts.
The trial description mentions Bayesian futility monitoring. This indicates that the study contemplated assessing whether continuing would be worthwhile if CASAD appeared not to be better than placebo. The monitoring description is not a report of the final result. The registry record does not report the decision rule, interim findings, or whether the futility recommendation was applied. Without those details, no conclusion about trial stopping or evidence strength should be drawn.
The record also lists the study model as single-group while describing randomization to CASAD and placebo. That inconsistency limits clarity about how the registry classifies the analysis, although the arm descriptions make the intended comparison apparent. The absence of the primary outcome results remains the central constraint: the posted registry information describes the question and design but does not answer the question.
9. Statistical Methods Explained
What does a randomized comparison contribute?
Random allocation is intended to make the treatment groups comparable, on average, with respect to factors that could influence an outcome. It supports a causal comparison when the assigned groups are analyzed appropriately and outcome information is sufficiently complete. Randomization does not guarantee identical groups, and it does not replace reporting the observed outcomes and their uncertainty. In this trial, the registry describes randomization between CASAD and placebo, but the primary outcome counts and analysis are not reported in the registry record.
The registry describes equal allocation and enrollment of 100. Those design details do not reveal how many participants experienced grade 3/4 diarrhea, whether all randomized participants were included in the analysis, or how missing outcome information was handled. The trial's own sample-size justification is not reported in the registry record.
How should a participant count be understood?
The primary measure is a count of participants who experienced grade 3/4 diarrhea during the stated timeframe. Although the endpoint is recorded as a count, its underlying status is binary for each participant: the event occurred or it did not. A comparison ordinarily needs both the number of participants with the event and the relevant denominator in each arm. The registry record does not report those primary-outcome counts or denominators, so an event proportion or between-arm estimate cannot be interpreted from the record.
For a binary outcome, investigators may report an absolute difference in event risk, a relative measure, or both. Each answers a different descriptive question, and each should be accompanied by uncertainty. No such primary comparison is reported. No effect measure should be reconstructed from the adverse-event counts, because those are a different outcome.
What is a confidence interval?
In general, a confidence interval conveys the precision of an estimated effect under the assumptions of the statistical method. It is not a range in which the true effect is guaranteed to lie. A narrow interval indicates that the estimate is more precise than a wide interval, while an interval spanning effects in opposing directions can leave the direction uncertain. Since the registry record does not report a primary effect estimate or confidence interval, its precision cannot be evaluated.
What does Bayesian futility monitoring mean?
In general, Bayesian monitoring updates the probability of possible treatment effects as outcome information accumulates, using both observed data and prior assumptions. A futility rule can recommend stopping when the accumulating evidence makes a worthwhile benefit seem unlikely under the chosen framework. The registry description says that Bayesian futility monitoring was used and that stopping was recommended if CASAD was clearly not better than placebo. It does not report the prior distribution, decision threshold, planned assessment timing, observed interim data, or whether the recommendation was followed. The method's mention is therefore not itself evidence that CASAD was or was not effective.
What can planning calculations tell readers?
In general, sample-size planning illustrates the amount of information a study might need under specified assumptions; it does not describe an observed result or establish the power achieved after the study. The registry's stated planning assumptions refer to a two-sided significance level of 0.05, equal allocation, a normal approximation, and effects expressed as fractions of an observed effect. These are planning assumptions, not evidence that the study detected an effect or that the assumed effect was true. The registry record does not report the trial's own sample-size justification. Any planning illustration based on an observed effect should be understood as hypothetical planning, not observed power.
How should masking be read?
Masking is intended to reduce the influence of expectations on care, event assessment, or reporting. The registry lists triple masking, while the official title says double blind. It does not explain which people were masked or reconcile the descriptions. The extent to which masking affected outcome assessment therefore cannot be determined from the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one primary outcome measure, but the outcome description says that the primary outcome has several categories or time points and is not reduced to one comparison. It does not specify which category or time point was selected for a single primary test, whether multiple comparisons were planned, or how any multiplicity was handled. The stated primary timeframe is the first 6 weeks from baseline in the initial intervention; further details about multiple outcome definitions or analysis choices are not reported in the registry record.
Multiplicity matters when several outcomes, time points, or subgroup comparisons are examined. In general, conducting many statistical tests can increase the chance of a seemingly notable result arising by chance. Prespecified outcome definitions and an analysis plan help readers distinguish the main confirmatory comparison from exploratory analyses. The registry record does not report enough detail to assess those choices for this trial.
Missing-data handling is also not reported in the registry record. It does not state whether all randomized participants were included in the primary analysis, how participants with incomplete follow-up were treated, or whether any imputation or sensitivity analysis was used. The primary outcome description refers to participants who experienced any diarrhea and participants who experienced grade 3/4 diarrhea, but it does not define the analysis population or denominator.
The record reports no analyses for the primary outcome. It is therefore not possible to assess analysis populations, missingness, multiplicity adjustments, or robustness to alternative assumptions from the registry information. These gaps limit interpretation independently of whether the intended study design was randomized and masked.
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 |
|---|---|---|---|
| Arm I: Calcium Aluminosilicate Anti-Diarrheal (CASAD) | 4 | 50 | 8.0% |
| Arm II: Placebo | 9 | 50 | 18.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Arm I: Calcium Aluminosilicate Anti-Diarrheal (CASAD) | 1 of 50 |
| Arm II: Placebo | 0 of 50 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 1% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Arm I: Calcium Aluminosilicate Anti-Diarrheal (CASAD) | 50 of 50 |
| Arm II: Placebo | 50 of 50 |
Most frequent serious adverse event terms
| Event term | Organ system | Arm I: Calcium Aluminosilicate Anti-Diarrheal (CASAD) | Arm II: Placebo |
|---|---|---|---|
| Neutropenia | Blood and lymphatic system disorders | 2 of 50 | 0 of 50 |
| Obstruction | Gastrointestinal disorders | 0 of 50 | 2 of 50 |
| Febrile Neutropenia | Infections and infestations | 1 of 50 | 1 of 50 |
| Abdominal Pain | General disorders | 0 of 50 | 2 of 50 |
| Renal Failure | Renal and urinary disorders | 0 of 50 | 1 of 50 |
| Fracture - skull | Musculoskeletal and connective tissue disorders | 0 of 50 | 1 of 50 |
| Hemorrhage - intracranial | Nervous system disorders | 0 of 50 | 1 of 50 |
| Creatinine - elevated | Renal and urinary disorders | 0 of 50 | 1 of 50 |
| Abdominal Distention | Gastrointestinal disorders | 0 of 50 | 1 of 50 |
| Dehydration | Gastrointestinal disorders | 1 of 50 | 0 of 50 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Arm I: Calcium Aluminosilicate Anti-Diarrheal (CASAD) | Arm II: Placebo |
|---|---|---|---|
| Fatigue | General disorders | 29 of 50 | 21 of 50 |
| Nausea | Gastrointestinal disorders | 23 of 50 | 25 of 50 |
| Constipation | Gastrointestinal disorders | 23 of 50 | 19 of 50 |
| Diarrhea | Gastrointestinal disorders | 31 of 50 | 0 of 50 |
| Vomiting | Gastrointestinal disorders | 13 of 50 | 16 of 50 |
| Anemia | Metabolism and nutrition disorders | 10 of 50 | 12 of 50 |
| Anorexia | Gastrointestinal disorders | 14 of 50 | 6 of 50 |
| Pain | General disorders | 11 of 50 | 9 of 50 |
| Alopecia | Skin and subcutaneous tissue disorders | 11 of 50 | 7 of 50 |
| Hyperglycemia | Metabolism and nutrition disorders | 9 of 50 | 8 of 50 |
Serious events with the highest arm-level rate: neutropenia (4.0%), obstruction (4.0%), abdominal pain (4.0%), febrile neutropenia (2.0%), renal failure (2.0%).
The registry lists serious adverse events for each arm, with 50 participants at risk in the CASAD arm and 50 in the placebo arm. Serious adverse events affected 4 participants in the CASAD arm and 9 in the placebo arm. Deaths were recorded for 1 participant in the CASAD arm and 0 in the placebo arm. These are descriptive counts, not estimates of the primary diarrhea outcome.
The registry also lists serious-event terms and percentages: Neutropenia and Obstruction at 4.0% each; Abdominal Pain at 4.0%; and Febrile Neutropenia, Renal Failure, and Fracture - skull at 2.0% each. The record does not specify the arm distribution for these listed terms in the information available, so the percentages should not be assigned to either arm.
In general, safety counts need context about event definitions, follow-up, exposure, and whether events were considered related to treatment. A serious event occurring during a trial does not by itself show that the assigned intervention caused it. The registry record does not report causal attribution or further safety-analysis methods. The counts should therefore be read as reported events, not as proof of comparative safety.
12. What the Result Does, and Does Not, Mean
The study was designed to compare CASAD with placebo on grade 3/4 diarrhea during the first 6 weeks of initial intervention in patients with metastatic colorectal cancer receiving irinotecan. The registry record reports the trial's phase, allocation, interventions, timeframe, and a description of Bayesian futility monitoring. These details explain the question the study set out to address.
They do not show the primary result. The registry record does not report the number of participants with grade 3/4 diarrhea in either arm, a difference between arms, an uncertainty interval, or a statistical test. It is therefore not possible to say from the posted registry results whether the primary endpoint favored either group or how precisely an effect was estimated. Neither the study title nor the stated rationale substitutes for outcome data.
The serious adverse-event and death counts provide safety information, but they do not answer the primary prevention question. They also do not establish a causal relationship between an intervention and an event. The serious-event terms are not allocated by arm in the listed information, so arm-specific interpretation of those terms is not supported.
In general, a result should be interpreted in light of the outcome definition, analysis population, missing data, and uncertainty. Those analysis details are not reported in the registry record. A completed study status does not itself establish that all outcome findings are posted. The defensible interpretation is therefore limited: the registry describes a randomized CASAD-versus-placebo study and reports some safety counts, but it does not contain enough primary-outcome information to determine the comparative finding.
13. Why This Trial Matters Statistically
This trial raises several useful statistical questions for clinical research. Its primary outcome is an event count within a defined period, but the registry record does not report the group-specific event counts or a comparative estimate. That illustrates why a trial's objective and design are not enough to evaluate its evidence: readers also need the outcomes, denominators, analysis method, and uncertainty.
The study description also distinguishes the initial randomized intervention from a later treatment pathway. Participants in either arm who developed grade 3 or 4 diarrhea could receive CASAD, though the pathway differed by initial assignment. Defining the primary comparison over the initial 6 weeks helps make clear which period is intended to address prevention. Later treatment, recurrence, and outcomes beyond that window would require separate definitions and reporting.
Another statistical issue is the mention of Bayesian futility monitoring without the decision rule or monitoring results. A monitoring method can affect when a trial stops and how its evidence should be interpreted. Describing the method without its assumptions and decisions leaves readers unable to assess that part of the design.
Finally, the registry's randomized comparison and its single-group model classification do not align clearly, and the masking descriptions differ between the title and registry. Such discrepancies do not determine the result, but clear design and analysis reporting helps readers understand what was compared and how. The record demonstrates why complete reporting is essential for translating a trial question into an interpretable statistical conclusion.
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 of the registry record is that it does not report the primary outcome results. There are no arm-specific grade 3/4 diarrhea counts, comparative effect estimate, or uncertainty interval. The primary prevention question therefore cannot be answered from the posted results, despite the detailed description of the intended endpoint and timeframe.
The endpoint description refers both to participants with any diarrhea and participants with grade 3/4 diarrhea, without clarifying the analysis population or denominator. The record does not report how missing outcome information was handled, whether all randomized participants were analyzed, or which statistical method was used for the primary comparison. It also does not clarify how the outcome's several categories or time points were addressed.
The design information has inconsistencies: the registry lists randomized allocation and a single-group model, and its masking description differs from the official title. The record does not resolve these classifications or identify who was masked. The futility-monitoring description lacks its decision threshold, timing, prior assumptions, and any reported decision.
Safety interpretation is limited by the absence of detail about event attribution and the arm distribution for the listed serious-event terms. The trial's own sample-size justification is not reported in the registry record. These limitations concern reporting and interpretability; they do not establish what the missing results would have shown.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Calcium Aluminosilicate Anti-Diarrheal in Treating and Preventing Diarrhea in Patients With Metastatic Colorectal Cancer Receiving Irinotecan — NCT00748215.
- Registry record last updated 2020-12-02; status last verified 2020-11.
- Results first posted 2020-12-02.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT00748215 is a completed phase II study of CASAD versus placebo in patients with metastatic colorectal cancer receiving irinotecan. The registry describes randomized allocation, enrollment of 100, and equal allocation between the arms. The primary outcome is the number of participants with grade 3/4 diarrhea during the first 6 weeks from baseline in the initial intervention.
The intervention descriptions specify oral treatment 4 times daily for 6 weeks, with a further CASAD treatment period for participants who developed grade 3 or 4 diarrhea. The record mentions Bayesian futility monitoring. It reports serious adverse events affecting 4 participants in the CASAD arm and 9 in the placebo arm, and deaths for 1 and 0 participants, respectively.
Arm-specific primary outcome results, a comparative estimate, and uncertainty are not reported in the registry record. The posted information therefore describes the study design and some safety counts without reporting the finding for its primary question.