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 Evaluation of Capsule Endoscopy in Patients With Suspected Crohn's Disease (NCT00487396), a non-randomized na study. The primary outcome is Diagnostic Yield in Suspected Crohn's Patients (CE Prior to IC vs. IC and SBFT).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00487396 |
| Phase | NA |
| Condition | Crohn's Disease |
| Allocation | Non-Randomized |
| Design model | Single Group |
| Masking | Single |
| Enrollment | 98 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Medtronic - MITG |
| Results posted | Yes |
2. Clinical Question
The study concerns patients with suspected Crohn’s disease and symptoms of abdominal pain and diarrhea. Its clinical question is whether capsule endoscopy (CE), performed before ileocolonoscopy (IC), improves diagnostic yield compared with standard diagnostic testing that includes IC and small bowel follow-through (SBFT). The registry also lists secondary diagnostic-yield comparisons of CE with SBFT and with IC.
Population
Patients with suspected Crohn’s disease and symptoms of abdominal pain and diarrhea. The registry lists enrollment as 98; the number included in each outcome analysis is not reported in the registry record.
Intervention
Capsule endoscopy, described as a device intervention and intended to precede ileocolonoscopy in the primary diagnostic question.
Comparator
The primary comparison is diagnostic yield for CE combined with IC versus IC combined with SBFT. The registry also lists CE versus SBFT and CE versus IC as secondary comparisons.
Primary question
Does adding CE before IC improve the detection of pathologies, such as ulcers or lesions, compared with the diagnostic yield of IC combined with SBFT?
This is a diagnostic question, not a comparison of treatment effects on symptoms, disease course, or other patient outcomes. Diagnostic yield concerns whether a procedure or procedure combination identifies relevant findings. The registry defines the primary outcome as a comparison of found and missed pathologies across procedure combinations. It does not report the observed yields, the numbers of findings, or the direction and precision of the comparison. Therefore, the record states what the investigators aimed to assess but does not establish the observed answer.
3. Trial Design
The registry identifies this as a completed study of capsule endoscopy in patients with suspected Crohn’s disease. It lists a single-group model and non-randomized allocation. Those design labels do not describe a randomized parallel-group trial with an allocated control arm. The record lists enrollment as 98, but does not report how many participants contributed data to each analysis or whether all enrolled participants completed each diagnostic procedure.
The intervention is capsule endoscopy, classified as a device. The primary objective concerns CE before ileocolonoscopy, compared with the diagnostic yield of IC combined with small bowel follow-through. The registry lists two secondary outcomes: diagnostic yield for CE versus SBFT and for CE versus IC. The exact sequence of tests, eligibility details, and any rules for selecting or interpreting findings are not reported in the registry record.
Masking is listed as single. Which people were masked, what information was concealed, and how masking was maintained are not reported in the registry record. The study phase is listed as NA. The sponsor is Medtronic - MITG. The record gives a study start of 2007-09, primary completion of 2010-10, and status of completed.
Because the study is non-randomized and recorded as single-group, any diagnostic comparison should not be read as a randomized treatment contrast. The registry’s stated comparison concerns diagnostic procedures and their yield, but it does not give the analysis-level participant flow or enough procedural detail to reconstruct how each comparison was formed. The actual results and any protocol deviations 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.
Before assignment: 98 patients enrolled in this study. 18 cases excluded due to the following: 15 cases were excluded due to noncompliance with the protocol. 1 patient withdrew consent before any study procedure. 1 patient could not ingest the capsule. 1 patient refused to undergo the ileocolonoscopy and SBFT. Therefore 80 patients were included in the analysis
Overall Study
| Stage | SB Capsule Then Standard Ileocolonoscopy |
|---|---|
| STARTED | 98 |
| COMPLETED | 95 |
| NOT COMPLETED | 3 |
Analysis population for the primary outcome, as defined in the registry: The number of found and missed pathologies (i.e. ulcers, lesions, etc.) were calculated for the combination of procedures.
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: 98 patients enrolled in this study. 18 cases excluded due to the following: 15 cases were excluded due to noncompliance with the protocol. 1 patient withdrew consent before any study procedure. 1 patient could not ingest the capsule. 1 patient refused to undergo the ileocolonoscopy and SBFT. Therefore 80 patients were included in the analysis
| Characteristic | Unit | SB Capsule Then Standard Ileocolonoscopy |
|---|---|---|
| Participants analysed | 80 | |
| Age, Categorical: <=18 years | Participants | 20 |
| Age, Categorical: Between 18 and 65 years | Participants | 60 |
| Age, Categorical: >=65 years | Participants | 0 |
| Age, Continuous | years | 28.35 (SD 13.25) |
| Sex: Female, Male: Female | Participants | 38 |
| Sex: Female, Male: Male | Participants | 42 |
| Region of Enrollment: United States | participants | 46 |
| Region of Enrollment: Israel | participants | 20 |
| Region of Enrollment: Sweden | participants | 14 |
6. Primary Endpoint
The registry lists the primary outcome as Diagnostic Yield in Suspected Crohn's Patients (CE Prior to IC vs. IC and SBFT), measured over four months from enrollment.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percentage of yield |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is diagnostic yield in patients with suspected Crohn’s disease, expressed in the registry as a percentage of yield. The stated timeframe is four months from enrollment. The objective is to assess whether capsule endoscopy before ileocolonoscopy improves diagnostic yield compared with ileocolonoscopy combined with small bowel follow-through.
The registry describes the underlying information as the number of pathologies found and missed, including examples such as ulcers and lesions, for combinations of procedures. Yield is useful in diagnostic research because it focuses on the detection of findings rather than on a treatment response. A comparison of yield can address whether the procedures identify different amounts or patterns of relevant pathology. It does not, by itself, establish the clinical importance of each finding or whether detecting a finding changes subsequent care or patient outcomes.
The outcome is labelled as a percentage of yield, while its parameter type is recorded as a number. The denominator, precise rules for counting a pathology, and handling of findings identified by more than one procedure are not reported in the registry record. Neither the observed yields nor the estimated comparison is reported in the registry record. Consequently, the endpoint definition conveys the intended measurement, but not the magnitude or precision of the observed result.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a planned diagnostic-yield comparison and names McNemar’s test for comparing the yield of IC combined with CE against the yield of IC combined with SBFT. It does not report the primary outcome result, an effect estimate, a confidence interval, or a p-value. The evidence available in the record therefore does not show whether the observed diagnostic yield favored either procedure combination, or how precisely any difference was estimated.
Diagnostic yield is a measure of detected findings under the definition used by a study. It is not interchangeable with sensitivity, specificity, predictive value, or overall diagnostic accuracy unless those measures are explicitly defined and estimated. The record’s stated focus on pathologies found and missed does not provide enough detail to determine how each of those accuracy measures was calculated. The registry’s summary aim refers to accurately diagnosing small bowel Crohn’s disease, but the posted primary outcome is diagnostic yield. The distinction matters: a higher yield alone does not describe false-positive findings, the correctness of every finding, or the effect of testing on patient outcomes.
The record lists enrollment as 98, but that figure does not establish the number analyzed for the primary outcome. The analysis count, procedure-specific denominators, missing observations, and participant flow are not reported in the registry record. No conclusion about completeness of follow-up or the representativeness of analyzed participants can be drawn from enrollment alone.
The non-randomized, single-group design also shapes interpretation. It does not provide a randomized assignment contrast, and the record does not describe an allocated control group. Comparisons among diagnostic procedures may be informative, but their interpretation depends on how procedures were applied, how findings were assessed, and whether the comparison is paired at the participant level. The registry names McNemar’s test, which is designed for paired binary outcomes; pair-level outcome data and the details needed to assess that structure are not reported in the registry record.
Thus, the posted record supports a description of the question, design labels, outcome definition, and planned test. It does not supply the result needed to judge the size, direction, or statistical uncertainty of the primary comparison. No treatment recommendation or conclusion about clinical benefit follows from the information recorded.
9. Statistical Methods Explained
The primary analysis is described as a McNemar test comparing diagnostic yield for IC combined with CE against yield for IC combined with SBFT. Understanding the test helps clarify what kind of data the stated analysis would use, but the registry does not report the underlying paired observations or the test result.
What does McNemar’s test assess?
In general, McNemar’s test is used for paired binary outcomes. Each paired unit contributes a result under each of two conditions, such as whether a finding was detected under each procedure combination. The test focuses on pairs with discordant results: those in which the outcome differs between conditions. Pairs with the same outcome under both conditions do not determine the direction of the contrast in the same way. This paired approach differs from a test designed for independent groups, because it accounts for the linkage between observations from the same unit.
For this study, the registry states that the test evaluates diagnostic yield for IC combined with CE compared with IC combined with SBFT. It does not report the paired data, how a pathology-level finding was translated into a binary outcome, whether the unit of analysis was the participant or an individual finding, or how multiple findings within a participant were handled. Those details are important for assessing whether the analysis structure matches the data.
What does a p-value say?
In general, a p-value measures how incompatible the observed data are with a specified null model, under the assumptions of the analysis. It is not the probability that the null hypothesis is true, nor does it measure the size or clinical importance of an effect. A small p-value cannot replace an effect estimate and its confidence interval. The registry does not report a p-value for the primary comparison, so no significance conclusion can be drawn from this record.
Why does an effect estimate need a confidence interval?
In general, a confidence interval describes the range of effect values that are reasonably compatible with the data and the statistical model at the stated confidence level. Its width reflects precision: a narrower interval indicates greater precision, while a wider interval indicates greater uncertainty. The interval also shows whether estimates compatible with the data include effects in different directions or a value representing no difference. No primary effect estimate or confidence interval is reported in the registry record.
What assumptions matter for diagnostic comparisons?
General considerations include the definition of a positive finding, consistency of interpretation across procedures, and whether the observations are paired as the selected test requires. If diagnostic findings are clustered within participants, treating every finding as independent may understate uncertainty. If procedures differ in when or how they are performed, those features can also affect the comparison. The registry does not report enough detail to determine how these issues were addressed.
The endpoint description says that found and missed pathologies were counted for procedure combinations, and the primary timeframe is four months from enrollment. It does not give a denominator for the percentage of yield, a complete operational definition of a positive result, or a rule for adjudicating disagreements. These are not minor presentation details: they determine what the estimated yield represents and what conclusions can reasonably be drawn from it.
How should planning calculations be read?
In general, a sample-size calculation is a planning exercise based on assumptions, not a result observed in a completed study. The planning illustration associated with this record uses a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; it defines the effect to detect as a stated fraction of the observed effect. Such assumptions describe a hypothetical planning framework, not the actual design of this non-randomized, single-group study. The record does not report a trial-specific sample-size justification. Any planning estimates are not observed power and should not be interpreted as evidence that the study did or did not have sufficient power.
For count outcomes, variability can exceed what a simple model assumes when observations are more dispersed than expected. In general, over-dispersion can make standard errors too small if it is ignored, leading to intervals that are too narrow and tests that appear more decisive than warranted. The primary endpoint is described as diagnostic yield and the named test is McNemar’s test; the record does not identify a count model or report an over-dispersion assessment. It would therefore be inappropriate to infer that a count model or a particular variance adjustment was used.
Overall, the methods description identifies a paired-comparison test and a diagnostic-yield objective, but leaves key implementation details and all primary numerical results unreported in the registry record. The test name alone is not enough to verify the analysis or interpret its result.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary diagnostic-yield outcome and two secondary comparisons: CE versus SBFT and CE versus IC. It records three outcome measures and three analyses. Testing several outcomes or contrasts can increase the chance of at least one apparently unusual result when all are considered together. General approaches to this issue include defining a hierarchy of hypotheses or adjusting the interpretation for multiple testing. The multiplicity strategy, if any, is not reported in the registry record. Without that information and the outcome results, the relationship between the primary and secondary analyses cannot be assessed.
Missing-data handling is not reported in the registry record. The record does not state how incomplete diagnostic procedures, unavailable outcome assessments, indeterminate findings, or withdrawals were handled. It also does not report the number of participants with missing outcome data or the assumptions used for any imputation or exclusion. Enrollment of 98 should not be treated as the analysis denominator in the absence of reported analysis populations and outcome-specific counts.
The analysis populations are not reported in the registry record. In particular, it is not stated whether analyses included everyone enrolled, only participants with completed procedure pairs, or another defined population. Because the design is described as non-randomized and single-group, there is no randomized intention-to-treat population to infer from the design labels. Participant flow, protocol deviations, and exclusions from each analysis are also not reported. These omissions limit assessment of selection, completeness, and comparability across diagnostic procedures.
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 |
|---|---|---|---|
| Adverse Events | 1 | 80 | 1.2% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Adverse Events | 0 of 80 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Adverse Events | 8 of 80 |
Most frequent serious adverse event terms
| Event term | Organ system | Adverse Events |
|---|---|---|
| Capsule Retention | Gastrointestinal disorders | 1 of 80 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Adverse Events |
|---|---|---|
| Abdominal Pain | Gastrointestinal disorders | 2 of 80 |
| Capsule retention | Product Issues | 2 of 80 |
| Weakness | General disorders | 1 of 80 |
| Nausea | Gastrointestinal disorders | 1 of 80 |
| Blood in stool | Gastrointestinal disorders | 1 of 80 |
| Skin irritation | Skin and subcutaneous tissue disorders | 1 of 80 |
| dehydration | General disorders | 1 of 80 |
Serious events with the highest arm-level rate: capsule retention (1.2%).
The adverse-event record lists 1 serious adverse event among 80 at risk, 8 other adverse events among 80 at risk, and 0 deaths. It also lists Capsule Retention as a top serious adverse-event term, with 1.2% recorded. These are registry entries and should be read as reported counts and a reported term, not as a complete account of event timing, severity grading, or causal relationship to the procedure.
The registry does not report the definition or observation period for these adverse-event summaries, whether events were assessed as related to capsule endoscopy, or how the at-risk population was defined. It does not give a detailed event narrative or explain how the listed serious-event term relates to the serious-event count. The primary endpoint timeframe of four months from enrollment should not be assumed to be the safety observation period, because that connection is not reported in the registry record.
These figures describe the posted safety entries but do not, on their own, establish comparative safety. The study is not described as a randomized comparison, and the registry does not provide an adverse-event comparison with a control group. No additional risk estimate should be inferred from the counts.
12. What the Result Does, and Does Not, Mean
The record documents an evaluation intended to compare diagnostic yield for capsule endoscopy used before ileocolonoscopy with yield for ileocolonoscopy combined with small bowel follow-through. It also identifies secondary comparisons of capsule endoscopy with each of those procedures. The primary endpoint focuses on pathologies found and missed, and the record names McNemar’s test for the primary comparison.
What the record does not establish is the observed diagnostic yield or the difference between procedure combinations. It reports no numerical primary result, confidence interval, or p-value. As a result, the direction, magnitude, and precision of the primary comparison are not reported in the registry record. The same limitation applies to the secondary comparisons: their outcomes are listed, but their results are not reported.
Even a reported difference in diagnostic yield would answer a limited question about findings detected under the study’s definitions. It would not automatically demonstrate improved overall diagnostic accuracy, establish that findings were clinically important, or show that testing changed patient outcomes. Those broader conclusions would require definitions and evidence not reported in the registry record.
The design labels also set boundaries on interpretation. A non-randomized, single-group study does not yield a randomized treatment-effect estimate. Any procedure comparison depends on the way tests were applied and findings assessed, details not fully reported in the registry record. Enrollment of 98 does not reveal the number analyzed or the completeness of paired observations.
The posted safety entries describe adverse-event counts and a listed serious-event term, but do not provide sufficient information to assess causality or comparative safety. Taken together, the record allows readers to identify the study’s diagnostic objective and some of its methods, while leaving the central efficacy-of-detection comparison and key analytic details unresolved. It does not support medical advice or a conclusion that a procedure is beneficial or ineffective.
13. Why This Trial Matters Statistically
This study’s statistical question is about how diagnostic yield is defined and compared, rather than how a treatment changes a clinical outcome. That distinction is important in biostatistics: the meaning of an estimate depends on the endpoint, its denominator, and the unit of analysis. The registry describes findings as found or missed and labels the endpoint as a percentage of yield, but does not report the complete calculation rule. Without that operational detail, readers cannot fully determine what a yield estimate would represent.
The named McNemar test also highlights a key design issue. In general, paired methods are appropriate when observations under two conditions are linked. The test’s interpretation depends on having a suitable paired binary outcome. The registry names the procedure combinations and test, but does not report the paired outcome data or explain how multiple pathologies were handled. This makes the study a useful example of why a statistical method should be considered alongside its data structure, rather than interpreted from its name alone.
Transparency about results is equally important. The registry identifies the primary and secondary diagnostic comparisons, yet numerical outcome results and uncertainty estimates are not reported in the registry record. Naming an endpoint and test does not tell readers the estimated effect or its precision. Without those results, statistical significance and practical importance cannot be evaluated.
Finally, the non-randomized, single-group design and the unspecified analysis populations limit what can be inferred about the comparison. The listed enrollment is not a substitute for analysis denominators or participant-flow information. These features illustrate why interpretation relies on both statistical methods and clear reporting of who contributed data, how outcomes were constructed, and what uncertainty surrounds the estimates.
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 trial-specific details needed to interpret diagnostic yield are not reported in the registry record. The endpoint is described in terms of pathologies found and missed, but the denominator for the yield percentage, the criteria for counting a finding, and the handling of multiple or overlapping findings are unspecified. The record does not explain how a finding was judged to represent Crohn’s disease or how disagreements between procedure results were resolved.
The primary timeframe is four months from enrollment, but the timing of each procedure and the relationship between the endpoint window and safety follow-up are not reported. The registry identifies single masking without identifying who was masked or what information was concealed. These gaps prevent assessment of whether interpretation of findings could have been influenced by knowledge of procedure results or other information.
The non-randomized, single-group design is not a randomized control comparison. The record does not provide sufficient procedural detail to establish exactly how comparisons were formed, whether all participants received each procedure, or whether all comparisons were paired at the participant level. The analysis populations, outcome-specific denominators, missing-data methods, and participant flow are not reported. The stated enrollment of 98 cannot resolve those uncertainties.
Finally, the primary and secondary outcome results are not reported in the registry record. No effect estimate, confidence interval, or p-value is available to assess the magnitude or precision of the diagnostic-yield comparison. These limitations apply to interpretation of the registry record and do not establish that the study itself did not collect such information.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Evaluation of Capsule Endoscopy in Patients With Suspected Crohn's Disease — NCT00487396.
- Registry record last updated 2020-10-22; status last verified 2020-09.
- Results first posted 2012-05-16.
- 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
The registry record for NCT00487396 is titled “Evaluation of Capsule Endoscopy in Patients With Suspected Crohn’s Disease.” It describes a completed, non-randomized, single-group study of capsule endoscopy in patients with suspected Crohn’s disease. Enrollment is listed as 98, masking as single, and phase as NA. The record lists a study start of 2007-09 and primary completion of 2010-10. The sponsor is Medtronic - MITG.
The primary objective is to compare diagnostic yield for capsule endoscopy before ileocolonoscopy with yield for ileocolonoscopy combined with small bowel follow-through. McNemar’s test is named for this comparison. Secondary outcomes compare diagnostic yield for capsule endoscopy with small bowel follow-through and with ileocolonoscopy.
The primary result, secondary results, effect estimates, confidence intervals, analysis populations, and missing-data methods are not reported in the registry record. Adverse-event entries list 1 serious adverse event, 8 other adverse events, and 0 deaths, with Capsule Retention recorded as a top serious-event term at 1.2%.