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 Survey on Anemia Therapy in Participants With Chronic Kidney Disease (CKD) Not on Dialysis (NCT02238067), a registered phase not stated study. The primary outcome is Percentage of Participants by ESA Types at Baseline.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02238067 |
| Phase | Phase not stated |
| Condition | Chronic Kidney Diseases |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 196 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Hoffmann-La Roche |
| Results posted | Yes |
2. Clinical Question
Population
Participants with chronic kidney disease who were not on dialysis and were treated with an erythropoiesis-stimulating agent (ESA) according to usual care and best-practice guidelines. The registry record describes the survey as taking place in Israel. Enrollment was 196; the primary outcome population is described as all enrolled participants.
Intervention
There was no assigned study treatment. Participants received ESA treatment as part of usual care. Physicians interviewed eligible participants and completed a satisfaction survey about anemia treatment at baseline and at the six-month follow-up. The record lists ESA and a satisfaction survey questionnaire as interventions.
Comparator
No comparator group is described. This was a non-interventional survey, not a randomized comparison of treatments. The ESA types in the primary outcome are categories whose baseline percentages were to be reported, not trial arms assigned by the study.
Primary question
What percentage of participants used each of the listed ESA types at baseline? The listed types were Mircera, Recormon, Eprex, and Aranesp. The registry record describes physician assessment through a satisfaction survey and specifies a 95% confidence interval as the measure of dispersion. It does not report the percentages or their confidence intervals.
The broader survey aimed to describe anemia-treatment patterns and participant satisfaction among people with chronic kidney disease who were not on dialysis. Secondary outcomes concerned CKD stages, injection administration and preferences about treatment frequency. Those descriptive questions do not create a treatment-versus-control comparison. The registry record does not report a causal question about whether one ESA is better than another, nor does it describe a randomized allocation or a comparison designed to estimate treatment effects.
3. Trial Design
This study is described as a prospective, non-interventional, cross-sectional, multicenter survey. It enrolled participants with chronic kidney disease who were not on dialysis and were receiving an ESA. Participating physicians were asked to interview eligible participants and complete a satisfaction survey about anemia treatment. The survey was scheduled at baseline and again at the six-month follow-up.
Because treatment followed usual care and best-practice guidelines rather than a study assignment, the design is observational. The registry record does not describe randomized allocation, a control group, or a protocol assigning participants to different ESA types. It therefore supports descriptive questions about treatment patterns and reported preferences, rather than a like-for-like comparison between assigned treatments. Differences among people receiving different ESA types could reflect their clinical circumstances or care context; this survey design does not by itself separate such factors from treatment choice.
The registry lists enrollment of 196 and gives the primary outcome population as all enrolled participants. It does not report how many participants contributed usable data to each outcome, whether every enrolled participant completed both surveys, or how missing responses were handled. The status is completed. The recorded study start is 2011-09, and primary completion is 2013-08.
The primary outcome concerned the percentage of participants by ESA type at baseline. The record also lists secondary outcomes about CKD stage, injection mode, interest in learning self-injection, perceived need for changes in treatment frequency, and preferred treatment frequency, including categories by ESA type or baseline frequency. The registry records 20 outcome measures overall. It does not report a prespecified statistical analysis plan, a sample-size justification, interim analyses, or methods for adjusting estimates for participant characteristics. Those details are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Chronic Renal Anemia Participants |
|---|---|
| STARTED | 196 |
| COMPLETED | 151 |
| NOT COMPLETED | 45 |
Reasons for not completing this period:
| Reason | Chronic Renal Anemia Participants |
|---|---|
| Not completed survey at Month 6 | 45 |
Analysis population for the primary outcome, as defined in the registry: All enrolled participants
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: All enrolled participants
| Characteristic | Unit | Chronic Renal Anemia Participants |
|---|---|---|
| Participants analysed | 196 | |
| Age, Continuous | years | 74.6 (SD 10.6) |
| Sex: Female, Male: Female | Participants | 85 |
| Sex: Female, Male: Male | Participants | 111 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Participants by ESA Types at Baseline, measured over Baseline.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | 95% Confidence Interval |
| Unit | percentage of participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint describes the percentage of participants using each ESA type at baseline. The registry lists Mircera, Recormon, Eprex, and Aranesp as the categories. This is a categorical, descriptive outcome: it summarizes how treatment use was distributed among the survey population at the start of observation. It does not measure change in anemia, clinical response, or a causal effect of one ESA compared with another.
Describing baseline treatment patterns is useful for understanding what therapies participants were receiving when the survey began. In a non-interventional survey, these figures can characterize practice in the enrolled population, while remaining dependent on who was eligible, enrolled, and represented in the recorded responses. The endpoint is not itself a measure of satisfaction; satisfaction was addressed through the survey, with additional outcomes concerning treatment preferences.
The registry record specifies a 95% confidence interval as the dispersion measure for this outcome. In general, a confidence interval conveys the uncertainty around an estimated percentage under the assumptions of the statistical method. It does not remove possible selection or measurement biases. Although the endpoint definition and interval type are recorded, the actual percentages and confidence intervals are not reported in the registry record. Consequently, the distribution among ESA categories and its precision cannot be interpreted from the registry information.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record defines a clear descriptive primary question: the percentage of participants in each ESA category at baseline. It identifies the categories and specifies a 95% confidence interval for the outcome, but it does not report any category-specific estimate or interval. As a result, the record does not establish which ESA type was most or least common in the enrolled population, nor how precisely any percentage was estimated.
That absence of estimates limits statistical interpretation. A confidence interval would ordinarily help readers judge how compatible the observed data are with a range of underlying percentages, subject to the method’s assumptions. Without the estimates and interval limits, neither the distribution nor its precision can be assessed. No p-value or treatment comparison is reported, and the study design does not describe a randomized comparison. The primary endpoint should therefore be understood as a planned descriptive measure, not evidence that one ESA outperforms another.
The registry describes a survey at baseline and six-month follow-up, and lists secondary measures about clinical stages, injection practices, interest in self-injection, and preferences for treatment frequency. It does not report the results for those outcomes. The study’s stated aim was to understand treatment patterns and satisfaction; the registry record alone does not show what participants reported or whether preferences changed between survey occasions.
Enrollment was 196, and the primary outcome population is identified as all enrolled participants. That does not establish that all enrolled participants had complete baseline data or contributed to every outcome. The number analyzed for each measure, missing responses, and handling of missingness are not reported in the registry record. In general, when response completeness varies, a percentage may depend on which participants contributed data and on the denominator used. Those details are necessary for a full assessment of representativeness and precision.
The registry lists serious adverse-event information for the participant group, including a serious-event count of 3 and serious-event terms each reported at 0.5%. Those entries are safety information, not the primary endpoint, and should be interpreted separately from treatment-pattern estimates. They do not supply a comparative safety analysis across ESA types. The separate deaths field is not reported in the registry record.
Overall, the record establishes the survey’s setting, design, target population, outcome definitions, and some safety entries. It does not provide primary or secondary outcome estimates, analysis methods, or sufficient detail on outcome denominators. Conclusions about prevalence, precision, comparative treatment effects, or changes over follow-up cannot be drawn from the recorded information alone.
9. Statistical Methods Explained
The primary outcome is a percentage: the share of participants in each ESA category at baseline. In general, a percentage is formed by relating the number of observations in a category to the relevant denominator. The registry identifies all enrolled participants as the primary outcome population, but does not report the category counts, the denominator actually used for each estimate, or the resulting percentages. It is therefore not possible to reconstruct or verify those estimates from the registry record.
The registry specifies a 95% confidence interval. In general, a confidence interval is an uncertainty range calculated from observed data using a statistical method and its assumptions. It describes the precision of an estimate; it is not a guarantee that the interval contains the underlying value, and it does not address bias from selection, measurement, or incomplete responses. For a percentage, precision depends on the amount of usable information and the distribution of responses. The interval method itself is not reported in the registry record, and no interval bounds are given.
The descriptive nature of the endpoint matters. The primary outcome summarizes ESA use rather than comparing outcomes between treatment groups. Although the registry lists several ESA types, participants were treated according to usual care, not assigned to those categories by randomization. In general, observed differences between categories in an observational study may reflect differences in the people receiving each treatment, as well as differences associated with treatment. A descriptive percentage alone cannot distinguish those explanations.
The survey is described as prospective and cross-sectional, with surveys at baseline and six-month follow-up. These features indicate that information was collected at planned occasions, but they do not by themselves specify a longitudinal statistical model or a method for comparing responses across occasions. The analysis used for repeated survey responses, if any, is not reported in the registry record. Nor does the record state whether each outcome used the same participants or denominator at both time points.
There are 20 outcome measures listed overall. In general, reporting many outcomes creates a multiplicity issue: when numerous statistical tests are conducted, the chance of at least one apparently notable result can increase. Whether that issue applies to a particular set of descriptive summaries depends on what analyses were planned and how results are interpreted. The registry records no analyses and does not report a plan for controlling multiplicity. It is not possible to infer whether formal tests or adjustments were intended.
The sample-size illustrations associated with the posted results are planning illustrations based on an observed effect, with stated assumptions of a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. In general, such an illustration asks how many participants per arm a hypothetical comparison might require for a chosen power under those assumptions. It is not the design basis documented for this survey, which has no described randomized arms, and it is not observed power. The registry record does not report a sample-size justification for the original survey. These hypothetical assumptions should not be treated as evidence that the study was designed or powered for a comparison between ESA types.
More broadly, the record does not describe the statistical procedures used to estimate percentages, confidence intervals, or any secondary outcomes. It does not report adjustment for potential confounders, a model for follow-up responses, a strategy for handling clustering across multicenter sites, or checks of model assumptions. These methods are not reported in the registry record. Their absence from the record does not establish that no such work occurred; it means the statistical approach cannot be evaluated from the recorded information.
In general, transparent reporting of methods and denominators helps readers distinguish a well-defined estimate from an estimate whose interpretation depends on undocumented choices. For this survey, the endpoint definition and confidence-interval level are recorded, but the actual values and the details needed to assess their calculation are not. Interpretation should remain limited to the design and definitions that are documented.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 20 outcome measures, including the baseline ESA-type percentage and secondary outcomes concerning CKD stage, injection practices, and treatment-frequency preferences. In general, examining many outcomes can raise multiplicity concerns if statistical tests are used: some apparently notable findings may arise by chance when many tests are performed. The registry record does not report an analysis plan, identify any multiplicity adjustment, or describe which outcomes were tested. It records 0 analyses. No inference about a correction strategy or testing hierarchy can be made from this information.
The primary outcome population is described as all enrolled participants, and enrollment was 196. The record does not report the denominator used for each percentage, outcome-specific analysis populations, or the number of participants with missing responses. It also does not explain whether incomplete questionnaires were excluded, whether missing values were imputed, or whether any sensitivity analyses were conducted. These details are not reported in the registry record.
In general, missing information can affect both the precision and the meaning of a percentage. If responses are unavailable for some participants, an estimate among respondents may not represent the full enrolled population when the likelihood of responding is related to treatment or participant characteristics. The registry does not provide enough detail to assess that possibility. The fact that the survey was scheduled at baseline and six-month follow-up does not establish that every participant completed both occasions or that paired changes were analyzed.
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 |
|---|---|---|---|
| Chronic Renal Anemia Participants | 3 | 196 | 1.5% |
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 |
|---|---|
| Chronic Renal Anemia Participants | 0 of 0 |
Most frequent serious adverse event terms
| Event term | Organ system | Chronic Renal Anemia Participants |
|---|---|---|
| Upper gastrointestinal haemorrhage | Gastrointestinal disorders | 1 of 196 |
| Cardiac failure congestive | Cardiac disorders | 1 of 196 |
| Chronic kidney disease | Renal and urinary disorders | 1 of 196 |
| Death | General disorders | 1 of 196 |
Serious events with the highest arm-level rate: upper gastrointestinal haemorrhage (0.5%), cardiac failure congestive (0.5%), chronic kidney disease (0.5%), death (0.5%).
The adverse-event information is recorded for the group titled Chronic Renal Anemia Participants. The registry lists 196 as at risk for serious adverse events and reports 3 serious adverse events. It also lists Upper gastrointestinal haemorrhage, Cardiac failure congestive, Chronic kidney disease, and Death as serious-event terms, each at 0.5%. These are registry entries and should be read as reported, rather than treated as a comparison between ESA types.
The separate fields for other adverse events show 0 at risk and 0 affected. Those entries do not provide a basis for estimating the frequency of other adverse events in the enrolled group. The deaths field is null; a death count is not reported in the registry record. The listed serious-event term Death at 0.5% is a term in the serious-event listing, and should not be substituted for the separate deaths field.
In general, safety counts need context about definitions, follow-up, ascertainment, and analysis denominators. The registry record does not provide detailed methods for collecting or adjudicating adverse events, nor does it report a safety comparison by ESA category. These figures therefore describe the entries recorded in the registry; they do not establish comparative risk or a causal relationship.
12. What the Result Does, and Does Not, Mean
The record describes an observational survey of ESA treatment patterns and treatment satisfaction among participants with chronic kidney disease who were not on dialysis. Its primary outcome is the baseline percentage in each of four ESA categories, and the registry specifies a 95% confidence interval. These details clarify what the primary measure was intended to describe.
The record does not report the primary percentages or confidence intervals. It also does not report the secondary outcome estimates. Thus, the posted registry information cannot establish the frequency of each ESA type, the precision of those percentages, the distribution of treatment preferences, or whether survey responses changed by follow-up. The design description and outcome definitions should not be mistaken for outcome findings.
Because treatment was not assigned and there was no comparator group, the survey is not a randomized test of one ESA against another. In general, a descriptive survey can characterize reported practice in its enrolled population, but it cannot by itself establish that a treatment caused an outcome or that one treatment is superior. The registry record does not describe an adjusted comparative analysis that would address differences among participants receiving different ESA types.
The safety entries likewise do not supply a comparative safety result. They report serious-event information for the group, but the registry does not provide detailed ascertainment methods or a breakdown by ESA type. The separate deaths field is not reported. Any broader interpretation would require information beyond the results recorded in the registry.
For readers, the key distinction is between what the registry documents and what remains unavailable. It documents the population, the survey approach, the baseline endpoint, its intended confidence-interval measure, and selected safety entries. It does not document the outcome estimates, outcome-specific denominators, missing-data handling, or a statistical analysis plan. Claims about treatment effectiveness, comparative safety, or participant preferences cannot be supported by these recorded details alone.
13. Why This Trial Matters Statistically
This survey raises a useful statistical distinction between describing treatment use and estimating treatment effects. Its primary outcome is a percentage distribution across ESA types at baseline. Such a measure can address how treatment was patterned in the enrolled survey population, but it is not a randomized contrast and does not quantify a causal effect. Recognizing the estimand—the quantity an analysis seeks to describe—helps prevent a descriptive endpoint from being interpreted as a comparative treatment result.
The registry identifies a confidence-interval level, which signals an intention to express uncertainty around percentages. But estimates and intervals are needed together to assess both the observed distribution and its precision. Because neither is reported, the endpoint’s statistical result cannot be evaluated, even though its definition is clear.
The survey also illustrates why denominator and missing-data reporting matter. A percentage is interpretable only in relation to the participants whose responses contributed to it. The record names all enrolled participants as the primary outcome population but does not report outcome-specific denominators or response completeness. Those omissions limit assessment of precision and representativeness.
Finally, the record lists multiple outcomes spanning treatment patterns and preferences. In general, a broad outcome set can be informative, but analyses need clear definitions and an interpretation strategy, particularly if formal tests are used. The registry does not report such a plan. The study is therefore statistically informative as a case for distinguishing observational description, uncertainty, multiplicity, and reporting completeness, while its recorded results do not support conclusions about treatment comparisons.
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 for interpretation is that the registry record does not report the primary outcome percentages or their 95% confidence intervals. It also omits the estimates for the secondary outcomes, so the stated questions about treatment patterns and preferences cannot be answered from the recorded results. The actual denominator for each estimate is not reported, despite the primary outcome population being described as all enrolled participants.
The non-interventional design is another important limitation for causal interpretation. Treatment followed usual care, and the record does not describe a randomized comparison or a control group. Any differences in descriptive results among ESA categories could not be attributed to treatment without further design and analysis information. The registry does not report adjusted analyses or the factors considered in treatment selection.
Although the survey was planned at baseline and six-month follow-up, the record does not report completion by occasion, paired-response counts, or how changes over time were analyzed. Missing-data handling and outcome-specific analysis populations are not reported in the registry record. The multicenter setting is stated, but methods addressing possible site-level variation are not reported.
The registry lists 20 outcome measures but does not report an analysis plan, procedures for multiplicity, or methods used to calculate estimates and intervals. It also does not give a sample-size justification for the survey. Finally, adverse-event collection and adjudication methods are not described, and the separate deaths field is not reported. Together, these gaps constrain evaluation of precision, completeness, representativeness, and safety interpretation.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Survey on Anemia Therapy in Participants With Chronic Kidney Disease (CKD) Not on Dialysis — NCT02238067.
- Registry record last updated 2017-03-24; status last verified 2017-02.
- Results first posted 2016-11-07.
- 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 describes a completed prospective, non-interventional, cross-sectional, multicenter survey of participants with chronic kidney disease who were not on dialysis and were receiving ESA treatment. Enrollment was 196. Physicians were to conduct interviews and complete anemia-treatment satisfaction surveys at baseline and six-month follow-up.
The primary outcome was the percentage of participants by ESA type at baseline, with a 95% confidence interval specified. The record lists 20 outcome measures overall, but does not report the primary or secondary outcome estimates, their intervals, outcome-specific denominators, missing-data methods, or a statistical analysis plan. It reports 3 serious adverse events and lists four serious-event terms at 0.5% each; a separate deaths count is not reported in the registry record.
The registry supports a description of the study design and intended measures, but the recorded information is insufficient to assess the treatment-pattern estimates, their precision, or comparative treatment effects.