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 Effectiveness of a Knowledge-based Intervention for Patients With Cutaneous Lupus Erythematosus (NCT01629784), a na na study. The primary outcome is Percentage of Subjects Who Correctly Answered a Knowledge Assessment Item Immediately Before and After an Educational Lecture.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01629784 |
| Phase | NA |
| Condition | Cutaneous Lupus Erythematosus |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 31 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Northwestern University |
| Results posted | Yes |
2. Clinical Question
Population
People with cutaneous lupus erythematosus (CLE) enrolled in the study. The registry record gives an enrollment of 31, but does not report further eligibility details or the demographic composition of the enrolled group.
Intervention
A behavioral intervention described as a CLE educational script: a lecture about CLE and sun protection. The study description says the teaching addressed skin-protection techniques, including sunscreen application and sun-protective clothing.
Comparator
There was no separate control group. The design is recorded as single-group, with knowledge assessed immediately before and after the lecture. The pre-lecture assessment is a baseline measurement, not a concurrent control condition.
Primary question
What percentage of participants correctly answered knowledge-assessment items immediately before and after the educational lecture? The registry also describes a later survey, after 3 months, about retained knowledge and application of the educational intervention. The actual percentages and the results of that follow-up assessment are not reported in the registry record.
3. Trial Design
This completed study evaluated a behavioral educational intervention for cutaneous lupus erythematosus (CLE). The registry identifies the intervention as a CLE educational script and describes an educational lecture about CLE and sun protection. Its stated purpose was to assess knowledge about risk factors and triggers, particularly sun exposure, and to evaluate teaching about skin-protection techniques.
The design is listed as single-group, with allocation recorded as not applicable and masking recorded as none. There is no separate randomized or concurrent control group. The immediate pre-lecture questionnaire therefore provides a baseline measurement for comparison with the post-lecture questionnaire; it is not an untreated control condition. Enrollment was 31. The registry lists Northwestern University as the sponsor and the study status as completed.
The primary outcome concerns the percentage of participants who correctly answered a knowledge-assessment item immediately before and after the lecture. The study description also says a survey was planned after 3 months to evaluate knowledge retention and application of the educational intervention. A secondary outcome is described in terms of the percentage correctly answering a knowledge or behavioral assessment item before and 3 months after an educational lecture.
The registry record does not report the actual outcome percentages, participant flow, or the statistical methods used to compare assessments. It also does not report details such as the lecture duration, questionnaire content, or how participants were selected. These omissions limit assessment of how the intervention was delivered and how broadly the findings might apply.
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 | Cutaneous Lupus Erythematosus (CLE) |
|---|---|
| STARTED | 31 |
| COMPLETED | 25 |
| NOT COMPLETED | 6 |
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 | Cutaneous Lupus Erythematosus (CLE) |
|---|---|---|
| Participants analysed | 31 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 28 |
| Age, Categorical: >=65 years | Participants | 3 |
| Sex: Female, Male: Female | Participants | 26 |
| Sex: Female, Male: Male | Participants | 5 |
| Region of Enrollment: United States | participants | 31 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Subjects Who Correctly Answered a Knowledge Assessment Item Immediately Before and After an Educational Lecture, measured over immediately before and after an educational lecture.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percentage of participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the percentage of participants who correctly answered a knowledge-assessment item immediately before and immediately after an educational lecture about CLE and sun protection. It is intended to measure knowledge at two points surrounding the teaching intervention. The record says participants completed a written questionnaire at both time points and that the percentage answering correctly was calculated for each.
This type of endpoint can describe whether the distribution of correct answers changed after an educational activity. It is relevant to the intervention’s immediate educational aim, but it does not by itself measure longer-term retention, changes in sun-protection behavior, disease activity, or quality of life. The registry separately describes an assessment after 3 months concerning knowledge and application.
The registry record does not report the item-level percentages, the number of questions, the number answering each item, or the analysis comparing pre-lecture and post-lecture responses. It therefore does not permit assessment of the size or precision of any immediate change. The word “percentage” identifies the planned measure; it is not itself evidence that knowledge increased.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a before-and-after educational assessment in a single group. Its primary question concerns the percentage of participants answering knowledge items correctly immediately before and after a lecture. However, the actual percentages and the results of any comparison are not reported in the registry record. There is consequently no reported effect estimate to interpret, and no basis in this record for quantifying an immediate knowledge change.
The same limitation applies to the later assessment. The study description refers to a survey after 3 months, and the listed secondary outcome concerns knowledge or behavioral assessment items before and after that interval. The registry record does not report the corresponding outcome values or a statistical analysis. It is therefore not possible to assess whether knowledge was retained or whether participants applied the educational content.
Even if pre- and post-lecture percentages were available, a single-group comparison would show change over time in the assessed group, not the effect relative to a concurrent control group. Without a separate control condition, other explanations for a difference—such as familiarity with the questionnaire or changes unrelated to the lecture—would not be ruled out by the design alone. This is a general limitation of uncontrolled before-and-after assessments, not a finding about what happened in this study.
The registry record does not report confidence intervals, p-values, item-level denominators, or other measures of uncertainty for the primary outcome. A percentage without its denominator or an uncertainty estimate can be difficult to judge, particularly when an assessment contains multiple items. The record also lists no analyses. Statistical significance, precision, and the consistency of responses across items therefore cannot be evaluated from the registry entry.
The stated enrollment and study status describe the record, but they do not establish how many participants completed each assessment or contributed to each outcome. The analysis population and missing-response handling are not reported in the registry record. The appropriate reading is therefore limited: the study was designed to assess knowledge around a lecture and at a later follow-up, but the registry entry does not give the outcome results needed to determine what those assessments found.
9. Statistical Methods Explained
The statistical question is about a percentage: the proportion of assessed participants who answered a knowledge item correctly. The primary endpoint specifies assessment immediately before and after an educational lecture. The planned measure is understandable, but the registry record does not report the observed percentages, item denominators, or analysis. Without those details, the size and precision of any change cannot be evaluated.
What does a percentage measure?
In general, a percentage expresses the share of observations meeting a defined condition. For this endpoint, the condition is a correct answer to a knowledge-assessment item. To interpret a percentage, readers need to know what counts as correct, how many participants answered the item, and whether the same participants contributed responses at both assessments. Those details are not reported in the registry record.
A percentage can be presented for each item or across a collection of items, but those approaches do not necessarily answer the same question. Item-level results describe knowledge of particular topics; a combined score may summarize performance across topics but depends on how items are selected and combined. The registry record identifies a knowledge-assessment item as the outcome unit, but does not report the questionnaire or scoring procedure. It is not possible to determine how results were aggregated or whether different items were analyzed separately.
How should a before-and-after comparison be understood?
In general, a pre-intervention assessment measures responses before teaching, while a post-intervention assessment measures responses after it. If the same people complete both assessments, their responses are related: each person’s later response can be compared with that person’s earlier response. Statistical methods for paired data account for this relationship. If the two sets of percentages are treated as independent, that relationship is not used. The registry record does not identify the comparison method or specify how missing responses were handled, so it is not possible to tell which approach, if any, was used.
A pre-lecture assessment is a useful baseline, but it does not provide the counterfactual comparison that a separate control group would offer. In general, a before-and-after difference in one group may reflect the teaching, repeated exposure to the questions, or other influences occurring over time. The design can describe change in the assessed group, but by itself cannot isolate the lecture’s effect from all other possible explanations.
What do uncertainty measures add?
In general, a confidence interval gives a range of values compatible with the data and the method used to calculate it. It communicates uncertainty around an estimate; it does not guarantee that the true value lies within the interval. A p-value, when reported, describes how compatible the observed data are with a specified statistical model or null hypothesis. Neither measure substitutes for the effect estimate, and neither establishes that an observed difference is important in practice.
No confidence intervals, p-values, or analysis results for the primary outcome are reported in the registry record. The actual percentages are also absent. Thus, neither the direction nor the magnitude of a difference can be checked, and its statistical precision cannot be assessed. This does not mean that the result was necessarily null; it means that the registry entry does not report the information required to interpret a result.
What can be learned from the planning assumptions?
The record gives assumptions for a sample-size planning illustration: a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. It labels this as a planning illustration computed from the observed effect, not as the trial’s own design. That hypothetical two-arm framework does not match the recorded single-group study design. The actual observed effect is not reported in the registry record, so the planning assumptions should not be read as evidence about the trial’s results or as a justification for its enrollment.
More generally, planning calculations estimate the sample size needed under specified assumptions. They are not observed power, and they do not establish that a study had adequate precision after data collection. A planning estimate depends on the anticipated effect and model assumptions; if those differ from the data or study design, the calculation may not describe the study’s actual ability to estimate an effect. No trial-specific sample-size justification is reported in the registry record.
The registry lists no analyses. It therefore does not identify a statistical test, an adjustment for covariates, a method for combining assessment items, or a plan for handling multiple comparisons. These absent details should not be inferred from the outcome description or the planning assumptions.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 2 outcome measures and describes a primary knowledge outcome plus a secondary assessment concerning knowledge or behavior after 3 months. The record does not report the questionnaire items or explain whether each item was analyzed separately, combined into a score, or selected for reporting after analysis. It also lists no analyses. A multiplicity adjustment, prespecified testing hierarchy, or other approach to interpreting several outcome comparisons is not reported in the registry record.
Multiplicity matters in general when several outcomes, time points, or items are tested. The more comparisons considered, the greater the chance that at least one may appear notable by chance under a statistical model. This does not establish that multiplicity affected this study; it means the record does not provide the analysis plan needed to assess that issue. Without item-level results and a declared approach, readers cannot distinguish a single planned test from a broader set of comparisons.
Missing-data handling is also not reported in the registry record. The entry gives enrollment and an adverse-event risk set, but it does not state how many participants completed each knowledge assessment, whether any item responses were missing, or how missing responses were handled. The analysis population—such as whether all enrolled participants or only those with paired assessments were included—is not reported. Consequently, the denominators underlying the outcome percentages and the possibility of differences between participants with and without observed responses cannot be assessed.
No imputation method, sensitivity analysis, or other missing-data strategy is reported. These gaps do not show that missing data or multiplicity changed the findings; they limit the ability to evaluate how outcomes were analyzed and how robust any result would be.
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 |
|---|---|---|---|
| Cutaneous Lupus Erythematosus (CLE) | 0 | 31 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Cutaneous Lupus Erythematosus (CLE) | 0 of 31 |
The adverse-event record lists 0 serious adverse events among 31 participants at risk and 0 other adverse events among 31 participants at risk. These are the recorded event counts for the CLE group. The registry does not list serious adverse-event terms.
Zero recorded events should be read as an observation in this registry entry, not as proof that an intervention has no possible risks. Event counts alone do not describe the completeness or duration of safety monitoring, and the registry record does not report those details. The intervention is described as behavioral education, but that does not remove the need to interpret safety data according to the monitoring and reporting information available.
The at-risk counts do not establish that every participant completed every study assessment or had the same observation period. The record does not give additional information on event definitions, collection procedures, or whether events were considered related to the educational intervention. The adverse-event figures therefore describe what was recorded, while leaving important context about ascertainment and follow-up unreported.
12. What the Result Does, and Does Not, Mean
The study addresses an educational question: whether knowledge about CLE and sun protection was assessed before and after a lecture, with a later survey also described. This makes the design relevant to evaluating immediate knowledge responses and, in principle, later retention or application. The registry record does not report the actual percentages or analysis results, so it does not show whether responses changed.
Even with reported before-and-after results, a single-group design would not by itself establish that the lecture caused any observed change. There is no separate control group in the recorded design. Repeating the assessment may affect responses, and other changes over time may also influence them. These are general considerations for uncontrolled before-and-after studies, not evidence that any particular influence occurred in this study.
The endpoint is a measure of correct answers, not a direct measure of sun-protection behavior, CLE severity, disease outcomes, or quality of life. The study description identifies behavior and quality of life as relevant concerns, but the registry entry does not report results for those outcomes. A knowledge score should not be treated as proof of behavior change or clinical benefit.
The record establishes the intervention type, broad assessment schedule, single-group design, and enrollment. It does not report the outcome values needed to judge the magnitude, direction, or precision of the findings. The appropriate conclusion is limited to what was planned and measured: the registry describes an educational assessment, but the posted record does not provide the results needed to determine what the assessment found.
13. Why This Trial Matters Statistically
This study illustrates the distinction between specifying an outcome and reporting its result. The primary measure is defined as the percentage answering knowledge items correctly before and after a lecture, and the record describes a later assessment. Yet the registry entry does not report the percentages, denominators, or statistical comparisons. Without these, readers cannot evaluate the magnitude or precision of the measured change.
The design also highlights the difference between a baseline and a control group. Repeating an assessment in one group can describe changes over time, but does not supply a concurrent comparison that separates intervention effects from other influences. That distinction is central when interpreting behavioral and educational evaluations.
The record’s planning assumptions provide another statistical lesson: a sample-size illustration based on a hypothetical two-arm comparison is not equivalent to the design recorded for the study. Planning calculations are conditional on their assumptions and do not replace a study-specific justification or observed result. The record does not report such a justification or its analysis methods.
Finally, the absence of reported outcome analyses leaves important questions unanswered about uncertainty, missing responses, and how multiple items were handled. These issues are not merely technical details: they determine what can be concluded from percentages and how confidently results can be generalized. The registry record makes the intended educational question clear, while its limited results reporting constrains statistical interpretation.
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 principal limitation for interpretation is that the registry record does not report the primary or secondary outcome values. Without the percentages, item denominators, and comparisons, the direction and size of any change cannot be evaluated. Measures of statistical uncertainty and the analysis results are also not reported.
The recorded single-group design has no separate control group. A pre-lecture assessment is a baseline, but it cannot by itself distinguish a lecture-related change from effects of repeated testing or other influences over time. This limits causal interpretation even if before-and-after results were available.
The registry record does not describe the assessment instrument, the number or content of its items, scoring rules, or whether the same items were used at each time point. It also does not report the number of participants contributing responses to each outcome, missing-data handling, or the analysis population. Those omissions constrain evaluation of measurement quality and the reliability of the reported percentages.
Details of participant characteristics and recruitment are not reported in the registry record. The rationale discusses differences across populations and emphasizes sun exposure, but the entry does not give the enrolled group’s demographic composition. Applicability to particular populations therefore cannot be assessed from this record. The lecture’s delivery details and safety-monitoring procedures are also not reported.
These limitations concern what can be established from the registry entry. They should not be taken as evidence that the study did not collect the relevant information; they indicate that the information is not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Effectiveness of a Knowledge-based Intervention for Patients With Cutaneous Lupus Erythematosus — NCT01629784.
- Registry record last updated 2013-06-03; status last verified 2013-04.
- Results first posted 2013-06-03.
- 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
This completed, single-group behavioral study evaluated a CLE educational script and lecture about CLE and sun protection. Enrollment was 31, with knowledge assessed immediately before and after the lecture. The study description also refers to a survey after 3 months about knowledge retention and application.
The registry record does not report the outcome percentages, analysis results, confidence intervals, p-values, analysis populations, or missing-data methods. It lists 2 outcome measures and no analyses. The adverse-event record reports 0 serious events and 0 other events among 31 at risk. The available entry describes the study’s question and design, but does not provide the outcome results needed to assess the observed knowledge changes.