Nurse Education in Subjects With Psoriasis Undergoing Treatment With Adalimumab: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Nurse Education in Subjects With Psoriasis Undergoing Treatment With Adalimumab (NCT01435265), a randomized na study. The primary outcome is Change in Psoriasis Area Severity Index (PASI-75).

2. Clinical Question

The trial asks whether adding nurse education to the usual education materials is associated with adherence to adalimumab treatment and with the primary reported outcome, the number of participants reaching PASI-75. It concerns people with moderate to severe psoriasis undergoing adalimumab treatment. The design compares normal nurse education with additional nurse education, but the registry record does not report a numerical adherence result or a statistical comparison of the primary outcome.

Adherence to adalimumab treatment is listed as a secondary outcome, while PASI-75 is the primary outcome. Those outcomes address related but distinct questions: adherence concerns whether participants followed the treatment regimen, whereas PASI-75 concerns a specified level of change in psoriasis severity. The posted results do not establish whether any observed difference in PASI-75 arose from education, treatment adherence, chance, or other influences. With only a few participants recorded in each arm and no comparative analysis reported, the results are descriptive rather than a precise estimate of an education effect.

3. Trial Design

The registry describes a phase IV, randomized, prospective, open-label study with a parallel-group design. The sponsor was Wake Forest University Health Sciences. The record lists the study start as 2010-01, primary completion as 2012-04, and status as completed. The enrolled total was 7.

Participants were assigned to normal nurse education or additional nurse education. The normal-education arm received usual nurse education materials, and the additional-education arm received further nurse education beyond those materials. The study is classified as behavioral; the interventions concern education rather than a randomized comparison of different drug regimens. The trial title and description situate the question among people with moderate to severe psoriasis receiving adalimumab.

Randomization is intended, in general, to make groups comparable on average at the time of assignment, including factors that may not have been measured. It does not ensure balance in every small trial, and the registry record does not report details of the randomization sequence or allocation concealment. The study was unmasked. Participants and study personnel therefore were not described as blinded to the education assignment. The record does not report whether outcome assessors were masked.

The primary outcome was the number of participants reaching PASI-75, with assessments listed at baseline, 1 month, 3 months, 6 months, 9 months, and 12 months; only final PASI-75 was to be reported. The primary outcome description identifies participants who completed the study as the analysis population. The posted arm results are 1 participant for Normal Nurse Education, with 3 participants in that arm, and 3 participants for Additional Nurse Education, with 4 participants in that arm.

Adherence to adalimumab treatment is listed as a secondary outcome. The registry record does not report the adherence outcome values, the way adherence was measured, or the statistical analysis plan. It also does not report a target sample-size justification or interim analyses. These absences limit assessment of how the trial was intended to address its question beyond the design and outcomes described in the 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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: All participants who completed the study.

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.

6. Primary Endpoint

The registry lists the primary outcome as Change in Psoriasis Area Severity Index (PASI-75), measured over Baseline, 1 month, 3 months, 6 months, 9 months, 12 months.

The primary endpoint is the number of participants with PASI-75 at the final assessment. PASI is a measure of psoriasis severity that combines assessments of severity and affected area across the head, trunk, upper extremities, and lower extremities. The registry describes scoring severity using erythema, infiltration, and desquamation, and states that an overall whole-body score is calculated. PASI-75 means a reduction of at least 75% in PASI score from baseline. The endpoint is therefore a responder count, not a mean change in PASI score.

A responder endpoint can make a clinically interpretable threshold explicit: it counts participants who meet a defined degree of improvement rather than retaining each participant’s full score change. As a general statistical point, converting a continuous measure into a yes-or-no outcome can make the result easier to communicate, but it also discards information about how far each person’s change lies above or below the threshold. The registry record does not report individual PASI changes or the distribution of scores.

The outcome description lists assessments at baseline, 1 month, 3 months, 6 months, 9 months, and 12 months, but specifies that only final PASI-75 will be reported. The primary outcome population is described as all participants who completed the study. The record does not report the specific final assessment date for each participant or how incomplete follow-up was handled. The posted results give responder counts by arm, without an estimable comparative effect or uncertainty interval.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The trial’s primary outcome is binary at the participant level: a participant either meets the PASI-75 threshold at the final assessment or does not. The posted result is expressed as counts of participants with the endpoint in each arm. This differs from reporting a continuous PASI score, where each participant’s measured score or change could contribute information about the size of the response.

What a two-arm comparison would address

In general, a statistical comparison of two randomized arms estimates how the outcome differs between the assigned groups, subject to assumptions and limitations of the design. For a binary outcome, an analysis might report a difference in event proportions, a relative measure, or another contrast, together with an uncertainty interval. These are general approaches, not analyses reported for this trial. The registry record says values were missing or not estimable for a two-arm comparison of the binary endpoint. It therefore does not provide a comparative estimate or its uncertainty.

That distinction matters: separate arm counts describe what was recorded in each group, while an inferential comparison quantifies the between-group contrast and its precision. Without the latter, the observed count pattern cannot establish whether a difference is compatible with chance variation or how large an underlying difference might be. No p-value or confidence interval for the primary comparison is reported in the registry record.

Why sparse binary data are difficult

As a general statistical matter, binary outcomes in small groups can yield sparse data. Some standard methods rely on approximations that may be unreliable when counts are limited. Exact methods or carefully selected models can sometimes be considered, but they do not create information that the trial did not collect, and their suitability depends on the analysis question and assumptions. The registry record does not identify a method used to estimate a treatment contrast. It would not be appropriate to infer an unreported method or calculate a new comparison from the arm counts.

Randomization is useful because it aims to prevent systematic allocation of participants according to prognosis or other characteristics. In a small randomized study, however, randomization does not ensure that baseline characteristics are balanced. The registry record does not report baseline characteristics or adjusted analyses, so the extent of any imbalance and the role of covariate adjustment cannot be assessed.

What open-label assignment means

The trial is listed as unmasked. In general, knowledge of assignment can influence participants’ experiences, behaviors, and reports, and can influence how study personnel deliver or assess an intervention. These concerns are especially relevant for an education intervention, because participants and educators may know which educational program is being used. The registry record does not describe masked outcome assessment or procedures intended to reduce measurement or reporting effects.

The primary endpoint is defined using a severity measure and a response threshold. In general, specifying a threshold can make the outcome straightforward to interpret, but it turns a range of possible score changes into a binary classification. A participant just meeting the threshold and a participant with a much larger reduction both count as responders. The registry record reports only final PASI-75 counts, not the underlying score changes, so that information cannot be recovered from the posted endpoint.

Analysis planning and interpretation

Good trial interpretation depends on a prespecified statistical plan that identifies the main comparison, analysis population, handling of missing outcomes, and any adjustment for multiple outcomes or repeated assessments. The registry record does not report the statistical plan, a sample-size justification, or interim analyses. Those items cannot be inferred from the randomization or the observed enrollment.

The record lists PASI-75 as the primary outcome, with several assessment times but only final PASI-75 designated for reporting. Adherence is listed as a secondary outcome. In general, having multiple outcomes or assessment times can raise questions about which tests are confirmatory and how multiplicity is handled. No multiplicity procedure is reported in the registry record, and the primary outcome’s designated final reporting does not by itself show what analysis decisions were made.

The registry’s sample-size assumptions describe planning illustrations based on an observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. Such illustrations are hypothetical planning calculations, not evidence about the probability that this completed trial detected an effect. They should not be called observed power. The record does not report the trial’s own sample-size justification, and no numerical planning estimates are available in the posted information.

In summary, the statistical record supports a descriptive reading of the PASI-75 counts only. The registry does not report an estimable between-arm analysis, the method for such an analysis, or the uncertainty around a comparative effect. General statistical principles explain why these details matter, but they cannot substitute for trial-specific methods and results that are not reported in the registry record.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Normal Nurse Education", "Additional Nurse Education-")
n      <- c(3, 4)
events <- c(1, 3)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Normal Nurse Education  3  1  33.3  0.8  90.6  6.1  79.2  6.8  80.6
ARM  Additional Nurse Education-  4  3  75.0  19.4  99.4  30.1  95.4  28.4  94.7

11. Multiplicity, Missing Data and Analysis Populations

The primary endpoint description identifies PASI-75 as the main outcome and lists assessments at baseline, 1 month, 3 months, 6 months, 9 months, and 12 months. It also states that only final PASI-75 will be reported. Adherence to adalimumab treatment is listed as a secondary outcome. The registry record does not report the statistical plan, the method used to choose or analyze outcomes, or a procedure for addressing multiplicity.

In general, multiplicity arises when several outcomes, time points, or statistical comparisons are examined. The more analyses considered, the greater the chance that at least one may appear notable by chance if results are interpreted without accounting for the broader set of analyses. This general concern does not establish that multiple testing occurred in this trial. The record does not report enough detail to determine what analyses were conducted or whether any adjustment was planned.

The primary endpoint population is described as participants who completed the study. The registry record does not report the number of participants who completed follow-up, the extent or reasons for missing outcome data, or the approach to handling missing values. It also does not report whether the analysis followed original randomized assignment for all participants or used another population definition. The stated completer population should therefore be distinguished from an intention-to-treat analysis, which is a general approach that retains participants according to randomized assignment regardless of later adherence or completion.

There are 0 analyses reported in the registry record. The absence of posted analyses leaves the handling of missing data and the relationship between the stated analysis population and the reported arm counts unclear. These gaps prevent a full evaluation of potential bias from incomplete follow-up or selective analysis.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Serious events with the highest arm-level rate: headache (50.0%), abdominal pain (33.3%), abscess on r lower leg (33.3%), depression (33.3%), diarrhea (33.3%).

The registry reports serious adverse events for all 3 participants at risk in the Normal Nurse Education arm and all 4 participants at risk in the Additional Nurse Education arm. It reports 0 other adverse events in each arm. These figures describe the posted participant counts; they do not establish the number of distinct event episodes, event timing, severity beyond the serious classification, or causal relationship to treatment or education.

The registry lists serious-event terms with percentages: Headache, 50.0%; Abdominal Pain, 33.3%; Abscess on R lower leg, 33.3%; Depression, 33.3%; Diarrhea, 33.3%; and Diverticulitis, 33.3%. The record does not make clear in the posted list how these terms are distributed by arm or provide the corresponding event counts. A person may experience more than one event, so term percentages should not be added or treated as mutually exclusive categories.

Deaths are not reported in the registry record. That is different from a report of no deaths. The safety figures are descriptive and arise from a very small study. They do not by themselves support a comparison of safety between groups or attribution of an event to adalimumab, nurse education, or another cause.

13. What the Result Does, and Does Not, Mean

The result means that the registry record reports different final PASI-75 responder counts in the two education arms: 1 participant among 3 in the Normal Nurse Education arm and 3 participants among 4 in the Additional Nurse Education arm. These are observations from the enrolled study participants. The record does not report an estimable statistical comparison, so it does not quantify the uncertainty around a between-arm effect.

The counts do not establish that additional nurse education caused a difference in PASI-75. Randomization supports a comparative question, but a very small study can produce unstable results, and the posted record lacks the comparative analysis needed to evaluate precision. The data also do not establish equivalence or no effect. An absence of a reported statistical comparison is not evidence that the groups had the same outcome.

The result does not show whether additional education improved adherence, because adherence is listed as a secondary outcome but its result is not reported in the registry record. Nor do the PASI-75 counts explain the underlying PASI score changes, since only responder counts are posted. The record does not allow readers to determine the degree of change among participants who did not meet the response threshold.

The endpoint is described for participants who completed the study, but completion and missing-outcome details are not reported. Consequently, the relationship between the enrolled groups and the analyzed endpoint counts cannot be fully evaluated. The record also lacks the planned sample-size justification and statistical analysis plan, making it impossible to judge the precision or intended inferential scope from those plans.

In practical statistical terms, the posted information is a small descriptive record rather than a precise estimate of the effect of an educational intervention. It documents the design, outcome definition, arm counts, and some safety information, while leaving important questions about analysis, missing data, adherence, and uncertainty unanswered. No clinical recommendation follows from these registry results alone.

14. Why This Trial Matters Statistically

This trial is statistically informative as an example of the gap between a randomized design and an interpretable comparative estimate. Randomization creates a framework for comparing education groups, but a very small enrollment can leave substantial uncertainty and can make a binary endpoint difficult to analyze. Here, the registry reports arm-level PASI-75 counts but no estimable two-arm comparison. That distinction is important: seeing counts in both arms is not the same as having a sufficiently precise estimate of the difference between them.

The study also highlights why endpoint and analysis-population definitions matter. PASI-75 is a threshold-based responder outcome, while the primary outcome population is described as study completers. The registry record does not report score-level changes, missing-data handling, or whether all randomized participants contributed to the endpoint analysis. Those details affect how readers understand what the counts represent and how broadly they can be interpreted.

Because this is an education intervention, the open-label design is also relevant to statistical interpretation. In general, awareness of group assignment can affect behaviors and measurement, and those possibilities should be considered alongside randomization. The record does not report masking of assessors or other safeguards, so the extent of these influences cannot be evaluated.

Finally, the registry lists adherence as a secondary outcome, but does not report its result or an analysis linking adherence to PASI-75. This leaves a central part of the intervention’s proposed pathway unquantified. The statistical lesson is not that the observed counts prove or disprove an educational effect, but that small enrollment, binary outcomes, incomplete analysis reporting, and absent uncertainty estimates sharply limit what can be concluded from a randomized study’s posted results.

15. 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 enrollment of 7 is small, and the arm counts are 3 for Normal Nurse Education and 4 for Additional Nurse Education. With so few participants, the reported responder counts are sensitive to individual outcomes, and a stable comparative estimate is difficult to obtain. The registry itself notes that the values were missing or not estimable for a two-arm comparison of this binary endpoint.

The primary outcome description defines the population as participants who completed the study, but the registry record does not report completion counts, reasons for non-completion, or missing outcome handling. It therefore does not show whether the posted endpoint counts cover all randomized participants. The record also does not report baseline characteristics, which prevents assessment of how similar the small groups were on measured factors before the intervention.

The study was open-label. The registry record does not report whether outcome assessment was masked or what steps were taken to limit possible influence of assignment awareness. This is relevant to an educational intervention and to a severity-based endpoint. The record does not describe the specific content, duration, or delivery procedures for the additional education beyond saying it went beyond normal education materials.

The primary endpoint is reported as a final responder count, and the outcome description says only final PASI-75 will be reported despite listing multiple assessment times. The record does not report individual PASI score changes or the adherence outcome values. It also does not report the analysis plan, sample-size justification, multiplicity handling, or any interim analyses. These limitations are specific gaps in the registry information; they do not establish what procedures were or were not used outside the record.

Safety interpretation is limited by the small groups and by the lack of event counts and arm-specific detail for the listed serious-event terms. Deaths are not reported in the registry record. Taken together, the available information supports descriptive reporting but not a precise comparative conclusion.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Nurse Education in Subjects With Psoriasis Undergoing Treatment With Adalimumab — NCT01435265.
• Registry record last updated 2018-08-29; status last verified 2018-07.
• Results first posted 2013-03-05.
• 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.

19. Record Summary

NCT01435265 is a completed phase IV randomized, prospective, open-label, parallel-group study sponsored by Wake Forest University Health Sciences. The registry lists a start of 2010-01, primary completion of 2012-04, and enrollment of 7. The study compared normal nurse education with additional nurse education among people with moderate to severe psoriasis undergoing adalimumab treatment.

The primary outcome was the number of participants reaching PASI-75 at final assessment. The posted counts were 1 participant among 3 in the Normal Nurse Education arm and 3 participants among 4 in the Additional Nurse Education arm. The registry record does not report an estimable two-arm comparison. Adherence to adalimumab treatment is listed as a secondary outcome, but its result is not reported in the registry record.

Serious adverse events were reported for all participants at risk in each arm; other adverse events were recorded as 0 in both arms. Deaths are not reported in the registry record. The analysis plan, sample-size justification, missing-data handling, and comparative uncertainty estimates are not reported. The record therefore supports a descriptive account of a small trial, not a precise estimate of the effect of additional nurse education.