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 Satisfaction in Patients Receiving the PegIntron Pen Plus Rebetol for Hepatitis C (Study P04244)(COMPLETED) (NCT00705263), a registered phase not stated study. The primary outcome is Number of Participants Satisfied With the PegIntron Pen, Including the Assessment of the Device Accuracy and Ease of Use..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00705263 |
| Phase | Phase not stated |
| Condition | Hepatitis C, Chronic, Hepacivirus |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 113 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Schering-Plough |
| Results posted | Yes |
2. Clinical Question
Population
Patients with chronic hepatitis C treated with PegIntron pen plus Rebetol. The registry record lists an enrollment of 113, but does not report how many participants contributed to the satisfaction outcome.
Intervention
The treatment regimen included peginterferon alfa-2b, identified as SCH 54031, administered with the PegIntron pen, and ribavirin, identified as SCH 18908 and referred to as Rebetol. The assessment concerned the pen and participants’ experience using it.
Comparator
No separate comparator group is described for the satisfaction question. The registry record does not describe a randomized comparison, and allocation is not stated. The described group should therefore not be read as a like-for-like treatment control comparison.
Primary question
After 4 weeks of treatment, how many participants reported satisfaction with the PegIntron pen, with satisfaction defined as a score of 5 or above on a 7-point grading scale? The record gives the outcome definition but does not report the number who met it.
The clinical question focuses on users’ experience with an injection device rather than on a comparison of clinical outcomes between treatment regimens. Participants were asked about the training they received for proper pen use, preparation and injection of the medicine, and their subjective impressions of using the pen. These topics describe distinct aspects of the experience: instruction, practical handling, and overall perception. The registry outcome combines them under a satisfaction assessment, but does not report separate scores for these topics.
The record’s stated rationale is that accuracy and ease of medicine administration are relevant to treatment effectiveness, and that assessing satisfaction could inform improvements to training for patients and health care providers. That rationale does not itself establish that the pen improved administration or treatment outcomes. The recorded endpoint is a participant-reported satisfaction count at a specified treatment time, not an objective measure of injection accuracy, adherence, or hepatitis C response. Those outcomes are not reported in the registry record.
3. Trial Design
The registry record identifies the study as an evaluation of satisfaction among patients receiving the PegIntron pen with Rebetol for chronic hepatitis C. Its official title places the study in Slovenia. The listed sponsor is Schering-Plough. The registry status is completed, with a start date of 2005-10 and a primary completion date of 2008-05. The record lists enrollment of 113. Enrollment does not establish how many participants completed the questionnaire or contributed to the primary outcome; that information is not reported in the registry record.
The described group consists of patients with chronic hepatitis C treated with PegIntron pen plus Rebetol, who answered questions on a patient questionnaire. The registry identifies peginterferon alfa-2b and ribavirin as the interventions. It does not describe a separate control group for the satisfaction endpoint. The record also states that this was not a randomized comparison and that allocation was not stated. The satisfaction assessment therefore addresses reported experience in the described treatment group, not a randomized contrast between devices or regimens.
The primary endpoint was assessed after 4 weeks of treatment. Participants evaluated training, preparation and injection, and their subjective impressions of pen use. Satisfaction was defined using a threshold on a 7-point scale. The registry record does not report questionnaire wording, how the scale’s response options were presented, whether the questionnaire was validated, or whether responses were collected by an independent assessor.
Further design details, including masking, eligibility criteria, recruitment procedures, the number of treatment sites, and the planned analysis method, are not reported in the registry record. The enrollment figure alone cannot establish the number with observed endpoint data, nor can it establish whether all enrolled participants received the same duration of treatment or completed the assessment.
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: 113 patients were enrolled in the study; however, data were available for 110 subjects
Overall Study
| Stage | Patients With Chronic Hepatitis C |
|---|---|
| STARTED | 110 |
| COMPLETED | 108 |
| NOT COMPLETED | 2 |
Reasons for not completing this period:
| Reason | Patients With Chronic Hepatitis C |
|---|---|
| Withdrawal by Subject | 2 |
Analysis population for the primary outcome, as defined in the registry: Patients with chronic hepatitis C treated with PegIntron pen plus Rebetol
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 | Patients With Chronic Hepatitis C |
|---|---|---|
| Participants analysed | 110 | |
| Age Continuous | years | 40.25 (SD 12.71) |
| Sex/Gender, Customized: Female | participants | 37 |
| Sex/Gender, Customized: Male | participants | 68 |
| Sex/Gender, Customized: Not provided | participants | 5 |
| Region of Enrollment: Slovenia | participants | 110 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Participants Satisfied With the PegIntron Pen, Including the Assessment of the Device Accuracy and Ease of Use., measured over After 4 weeks of treatment..
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Satisfied Participants |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the number of participants satisfied with the PegIntron pen, including an assessment of device accuracy and ease of use. The registry defines satisfaction as a score of 5 or above on a 7-point grading scale and sets the assessment after 4 weeks of treatment. The questionnaire asked participants to evaluate training in proper pen use, preparation and injection of the medicine, and their subjective impressions of using the pen.
A count is useful for expressing how many participants met the stated satisfaction threshold. It is not, by itself, a proportion: interpretation of a count in relation to the number assessed requires a denominator. The registry record does not report the number completing the questionnaire, the number with usable responses, or the count meeting the satisfaction definition. It therefore does not allow the reader to determine the observed frequency of satisfaction or its precision.
The endpoint captures a patient-reported experience at a defined time. A threshold can make a response easier to communicate as a satisfied/not-satisfied classification, but it also compresses the underlying scale. Participants with different scores may be grouped together, and the record does not provide the distribution of scores. The endpoint does not directly measure technical injection accuracy, adherence, or clinical response. Those distinctions matter because satisfaction may be relevant to device usability without being a substitute for those other outcomes.
The endpoint is used to address the study’s stated interest in patients’ experience and possible improvements to training. Whether it supports those conclusions depends on the observed results, response completeness, and the way the questionnaire was administered. The outcome value and those supporting details are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record defines a clear outcome question but does not include the result needed to answer it. It names the primary outcome as a count of participants meeting the satisfaction threshold after 4 weeks of treatment. No numerical count, scale distribution, or denominator for that assessment is reported in the registry record. Consequently, the posted information cannot establish how many participants were satisfied, what fraction of those assessed met the threshold, or how precise an estimate would be.
The enrollment of 113 is not interchangeable with the endpoint denominator. Some enrolled participants may not have completed the assessment or may have had missing responses, but the registry record does not report whether that occurred. It would be inappropriate to treat all enrolled participants as having an observed satisfaction response without a reported analysis population and missing-data account.
The endpoint is descriptive and participant-reported. In the absence of a distinct comparator, it can describe reported experience in the treated group if results are available; it cannot by itself establish that the pen is more satisfactory than another device or that the regimen caused a particular level of satisfaction. The registry record explicitly notes that this is not a randomized comparison and that allocation is not stated. It does not report comparative estimates, adjusted analyses, or uncertainty intervals.
The record lists one outcome measure and zero analyses. This means the registry entry does not display an analysis for the endpoint. It does not establish whether analyses were conducted outside the record, and no specific statistical method, estimate, or test result is reported in the registry record. There is therefore no basis for describing statistical significance, estimating an association, or drawing a conclusion about the precision of an outcome estimate.
The adverse-event entries list 0 participants affected for both serious and other events in the group, while the numbers at risk and deaths are not reported in the registry record. Without the relevant denominators and fuller event information, these entries do not establish event rates or provide a complete safety assessment. They also do not fill the gap in the primary satisfaction result.
Overall, the posted information supports description of the study question, its population, and its endpoint definition. It does not supply the observed satisfaction result needed to characterize participants’ experience. Any interpretation beyond those design details would require outcome and analysis information that is not reported in the registry record.
9. Statistical Methods Explained
The registry identifies the endpoint as a number of participants rather than a mean score. In general, a count records how many individuals meet a specified condition. For this study, the condition is a satisfaction score of 5 or above on a 7-point grading scale. The count is meaningful only alongside a defined population at risk of being counted, such as participants who completed the questionnaire and had an interpretable response. The number assessed is not reported in the registry record, so the endpoint’s denominator cannot be established from the posted information.
What does a thresholded satisfaction outcome represent?
In general, turning a scale into a thresholded outcome creates two categories: participants whose score meets the threshold and those whose score does not. This can be straightforward to communicate, but it discards detail about scores within each category. A participant just below the threshold and a participant with a much lower score would be treated alike for the count, as would participants with different scores at or above the threshold. The record does not give the individual score distribution, so it is not possible to examine how close responses were to the cut point or whether satisfaction was concentrated at particular scale values.
The threshold is part of the endpoint definition, not a statistical finding. It specifies how the count is formed, but does not show that participants met the threshold. The registry record does not report the number meeting it or the questionnaire’s full response pattern. It also does not report whether the score was analyzed in any other way.
How would uncertainty be described in general?
For a count derived from participant-level responses, an estimate of the proportion meeting the criterion would ordinarily be interpreted with its denominator and an uncertainty interval. In general, a confidence interval describes a range of values compatible with the observed data under the method used; it is not a guarantee that the true value falls in that range. The registry record reports neither an outcome denominator nor a confidence interval. No interval or proportion can therefore be quoted for this endpoint.
Statistical precision depends on the amount of usable information, not simply on the enrollment figure. A recorded enrollment of 113 does not disclose how many participants posted a valid response. Nor does it reveal how the outcome was handled for participants without a response. The registry record does not report a missing-data method, a rule for excluding incomplete questionnaires, or an analysis population. These omissions prevent a reader from assessing whether the available responses represent the enrolled group.
What can be said about the analysis plan?
The record lists one outcome measure and zero analyses. It does not report a statistical analysis plan, a test, a model, a confidence interval method, or a prespecified approach to missing values. The absence of a listed analysis should be understood as a limitation of what is recorded, not proof that no analysis was ever performed. There is no posted estimate from which to assess statistical significance or precision.
In general, a statistical method should match the outcome and the study question. A count of people meeting a criterion differs from a continuous score, and a single-group descriptive question differs from a randomized comparison. If the purpose is to describe the treated group, the count and the number assessed are central. If the purpose is to compare groups, the design and a suitable between-group estimate are needed. The registry record describes no like-for-like control comparison for this endpoint, so a comparative treatment effect cannot be inferred.
Over-dispersion is a general concern in some count-data models when observed variability exceeds what the model assumes. It matters because an inappropriate variance assumption can make uncertainty estimates misleading. That concept does not establish that an over-dispersed model was needed for this endpoint: the endpoint is a count of participants meeting a binary threshold, and the record reports no model or participant-level data from which to evaluate variability. No claim about over-dispersion or model fit can be made for this study.
How should planning calculations be read?
In general, sample-size planning asks how much information a future study might need to detect a specified effect under stated assumptions. A planning illustration based on an observed effect is not the trial’s original design justification and is not observed power. It depends on the effect value and analysis assumptions used. The registry record does not report a sample-size justification or a numerical outcome estimate for this satisfaction endpoint. Any planning illustration should therefore not be mistaken for evidence that the study was adequately powered, nor for an observed treatment effect.
These distinctions are especially important for a single-group satisfaction assessment. Planning for a comparison requires a defined comparator and a target contrast; the record does not describe such a comparison for the primary question. No inference about a comparative effect, its precision, or statistical significance can be reconstructed from the endpoint definition and enrollment alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists one outcome measure and zero analyses. The stated primary measure is the count of participants satisfied with the PegIntron pen, including assessment of device accuracy and ease of use. The record does not report a multiplicity strategy, such as how multiple outcomes or repeated analyses would be handled. Since no analysis is listed, the posted information does not establish whether multiplicity was a practical issue in the study’s conducted analyses or whether any adjustment was made.
Missing data are also not described. The enrollment figure does not identify how many participants completed the questionnaire after 4 weeks, how many responses were usable, or how incomplete responses were treated. The registry record does not report an imputation method, a complete-case rule, or sensitivity analyses. Without those details, readers cannot assess the effect that missing responses might have on the satisfaction count.
The analysis population is not specified. It is not reported whether the endpoint included all enrolled participants, only those who began treatment, only those who reached the assessment time, or another group. The description says that treated participants answered questionnaire questions, but it does not quantify participation or completion. Enrollment should therefore not be interpreted as the number analyzed.
These omissions limit reproducibility and interpretation. A clear accounting of the number assessed, the number with missing responses, the endpoint count, and the analysis population would be needed to evaluate the result. None of those outcome details is reported in the registry record.
11. What the Result Does, and Does Not, Mean
The study’s stated purpose is to evaluate patient satisfaction with the PegIntron pen and to inform improvements to training for patients and health care providers. The primary endpoint reflects participants’ subjective assessment after 4 weeks of treatment, using a defined score threshold. This gives the clinical question a practical focus on training, preparation, injection, and experience using the device.
The registry record does not report the number of participants who met the satisfaction threshold, the number assessed, or the distribution of questionnaire scores. As a result, the posted information cannot establish whether satisfaction was common or uncommon, nor how precisely it was estimated. It also cannot show whether participants’ views differed across the aspects of use included in the questionnaire.
Even if a satisfaction count were available, this endpoint would represent reported experience rather than a direct measure of accurate dosing, adherence, or clinical response. In general, satisfaction can be informative about usability and acceptability, but it should not be treated as proof of those other outcomes. The record does not report results for them.
The study description does not identify a separate comparator for the satisfaction assessment and does not describe a randomized comparison. Therefore, the endpoint cannot be interpreted as demonstrating that this pen is more or less satisfactory than another device, or that it caused a particular experience relative to an alternative. The registry rationale connecting administration accuracy and ease of use with treatment effectiveness is a rationale for evaluating the device; it is not an outcome result.
The record’s completed status and enrollment figure describe study registration, not the completeness or strength of the endpoint evidence. Since the numerical satisfaction result and its denominator are not reported in the registry record, conclusions about the observed level of satisfaction, uncertainty, and generalizability remain unavailable.
12. Why This Trial Matters Statistically
This study illustrates the distinction between a clearly stated patient-reported endpoint and a result that can be interpreted quantitatively. The registry defines what counted as satisfaction, identifies the assessment time, and describes the questionnaire topics. Those details clarify the intended measurement. Yet without the number meeting the definition and the number assessed, the primary question remains unanswered in the posted record.
It also highlights why enrollment and analysis denominators should not be conflated. Enrollment of 113 is recorded, but the registry does not report whether all enrolled participants completed the assessment. For a count of satisfied participants, the number with an observed response is essential to judging how the count relates to the group studied. Reporting only enrollment does not resolve that issue.
The endpoint further demonstrates the interpretive trade-off in thresholding a scale. A threshold can offer a compact summary, while losing information about the range and distribution of participants’ experiences. Reporting both the threshold-based count and the underlying score distribution can, in general, preserve more context. The registry record does not report the distribution.
Finally, the study is a reminder that a usability question and a treatment-effect question are different. Satisfaction with a pen can inform understanding of device experience, but this record does not present a randomized comparison or clinical outcome results. Clear communication of these boundaries helps prevent a descriptive endpoint from being read as evidence of comparative effectiveness or safety.
13. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The central limitation for interpretation is that the registry record defines the primary endpoint but does not report its observed value. Neither the number meeting the satisfaction threshold nor the number assessed is given. No score distribution or uncertainty estimate is reported, so the magnitude and precision of the satisfaction result cannot be evaluated.
The endpoint is based on participants’ subjective impressions and combines evaluation of training, preparation and injection, and pen use. The registry does not report separate results for these topics, the questionnaire wording, or evidence about the measurement properties of the instrument. The thresholded definition also does not preserve the full scale distribution in the single stated count.
The assessment is specified after 4 weeks of treatment. The record does not describe later assessments, so it cannot establish how experience might change over time. It also does not report the number of participants who completed the assessment or the treatment exposure among those assessed.
No separate comparator is described, and the registry notes that the study was not a randomized comparison with allocation not stated. The satisfaction endpoint therefore cannot support a like-for-like device comparison. The record also does not report an analysis method, missing-data approach, or analysis population. These limitations are specific to interpreting this endpoint and its completeness, rather than evidence that the study necessarily lacked procedures not entered in the registry.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Satisfaction in Patients Receiving the PegIntron Pen Plus Rebetol for Hepatitis C (Study P04244)(COMPLETED) — NCT00705263.
- Registry record last updated 2009-08-25; status last verified 2009-08.
- Results first posted 2009-07-17.
- 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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17. Record Summary
NCT00705263 is a completed study evaluating satisfaction among patients with chronic hepatitis C receiving PegIntron pen plus Rebetol. Its official title identifies Slovenia, and Schering-Plough is listed as sponsor. The registry record gives a start date of 2005-10, a primary completion date of 2008-05, and enrollment of 113.
The primary outcome is the number of participants satisfied with the PegIntron pen after 4 weeks of treatment, with satisfaction defined as a score of 5 or above on a 7-point grading scale. The questionnaire covered training, medicine preparation and injection, and subjective impressions of pen use. The record lists one outcome measure and zero analyses, but does not report the satisfaction count, outcome denominator, or analysis population.
The record does not describe a randomized comparison or a separate comparator for the satisfaction question. Missing-data handling, statistical methods, and a sample-size justification are not reported in the registry record. The posted entry therefore establishes the study question and endpoint definition, but not the numerical result needed to characterize participants’ satisfaction.