Preoperative Survey to Evaluate Patient Allergy: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Preoperative Survey to Evaluate Patient Allergy (NCT05670756), a registered phase not stated study. The primary outcome is True Allergy (Consistent With an IgE-mediated Reaction).

2. Clinical Question

3. Trial Design

The registry describes a completed survey study at Nationwide Children's Hospital. Its stated focus is the medication allergy list in the electronic medical record for patients presenting for surgery, together with the symptoms that prompted those allergy entries. Participants were asked to complete a REDCap survey on an iPad during the visit. The intervention is classified as a survey, rather than a drug or procedure.

The record lists enrollment of 250 and an enrollment period beginning 2023-05-01, with primary completion on 2023-11-13. The status is COMPLETED. The listed arm is patients with a medication allergy in their electronic medical record. There is no reported control arm or randomized allocation, so the study does not support a like-for-like treatment comparison.

The study aims to describe allergy demographics and prevalence, examine the decision-making behind allergy identification, and assess potential relevance to perioperative care. These aims are descriptive and evaluative. The registry does not establish that survey responses changed clinical decisions or patient care.

The primary outcome is recorded as a number of allergies, with baseline as its timeframe. The registry also lists two secondary outcome categories concerning allergies judged unlikely to be true or not to be true. Although it lists three outcome measures overall, the numeric results for these measures are not reported in the registry record. A statistical analysis plan, including details of any models or uncertainty estimates, is 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

Analysis population for the primary outcome, as defined in the registry: In the 250 participants, there were at total of 301 medication allergies reported due to some participants being allergic to multiple medications.

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 True Allergy (Consistent With an IgE-mediated Reaction), measured over Baseline.

The primary endpoint is the number of medication allergies classified as true allergies consistent with an IgE-mediated reaction. Its operational definition includes specified cutaneous reactions—hives, urticarial, skin redness, or rash—within 6 h of a dose, or anaphylaxis or an anaphylactoid reaction within 6 h of a dose. The stated timeframe is baseline.

This measure is used to distinguish allergy-list entries that meet the study’s symptom-and-timing definition from entries that may be less consistent with that definition. That distinction is relevant to the study’s descriptive aim of examining how medication allergies were identified and their potential relevance to perioperative care. It should not be read as a test of treatment effectiveness.

The measurement unit is allergies, not participants. The registry states that the 250 participants reported 301 medication allergies because some participants were allergic to multiple medications. These are different units of observation: one person may contribute more than one allergy entry. The numeric count meeting the primary endpoint definition is not reported in the registry record, so the proportion of listed allergies meeting the definition cannot be interpreted from these registry entries.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What is being counted? The primary endpoint is a count of allergies meeting the stated reaction definition. A count can describe the number of qualifying events or entries in the observed records. Here the unit is explicitly allergies, while the study population is described in participants. Because some participants had multiple medication allergies, the two units should not be conflated. A count of qualifying allergies would not automatically equal a count of participants with at least one qualifying allergy.

The registry reports 250 participants and 301 medication allergies. Those figures indicate that allergy entries can be clustered within participants. In general, observations from the same person may share characteristics and may not be statistically independent. If an analysis treats each allergy entry as independent when entries from one participant are related, uncertainty can be understated. Whether the study used a method to account for this clustering is not reported in the registry record. This is a general statistical consideration, not a claim about an analysis that was performed.

How does a classification rule work? The primary outcome uses a prespecified description of reactions and their timing: certain cutaneous reactions within 6 h of a dose, or anaphylaxis or an anaphylactoid reaction within 6 h of a dose. Such a rule makes the intended classification more concrete and can improve consistency. It does not, by itself, show that every record contained enough detail for classification, that reviewers applied the rule reliably, or that the classification was validated against another diagnostic standard. Those details are not reported in the registry record.

What can a descriptive count tell readers? A count can summarize the number of observed entries that satisfy a definition. For interpretation across a population, readers often also need a denominator and an estimate of uncertainty. The relevant denominator depends on the question: allergy entries for the share of entries classified in a category, or participants for the share of people with at least one such entry. No resulting count or proportion for the primary endpoint is reported in the registry record, and no confidence interval is reported. A confidence interval is a statistical range that expresses the uncertainty around an estimate under the assumptions of the analysis. It cannot be assessed without a reported estimate and method.

In general, count data may vary more than a simple model assumes, a feature called over-dispersion. Repeated observations within a participant can also produce dependence. Models for counts or clustered data can address these features when appropriate, but the choice depends on the question and data structure. The registry does not report a model, an over-dispersion assessment, or an adjustment for repeated allergy entries. It is therefore not possible to attribute any particular method to the study.

What does the record say about analysis? It lists three outcome measures and zero analyses. This does not give the methods, estimates, or uncertainty for the outcomes. The statistical analysis plan, including any adjustment, subgroup analysis, or interim analysis, is not reported in the registry record. The analysis population and rules for excluding or retaining incomplete records are also not reported.

How should planning calculations be understood? Any sample-size figures associated with planning are illustrations, not observed power and not evidence about the study’s design justification. The stated illustration assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect set as a stated fraction of the observed effect. Those assumptions describe planning calculations; they do not establish that the survey study had two randomized arms. The record does not report a sample-size justification for the actual study, and the listed study design has no comparator arm. Planning illustrations should not be interpreted as observed results or as a substitute for the missing outcome estimates.

In general, a significance test addresses compatibility between data and a statistical null hypothesis under a model; it does not measure the size or practical importance of an effect. Confidence intervals and the underlying estimates are also needed to assess precision. The registry entries do not report a primary endpoint estimate, a test, a p-value, or an interval, so inferential conclusions cannot be drawn from this record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists three outcome measures: one primary category for true allergy consistent with an IgE-mediated reaction, and two secondary categories concerning unlikely true allergy and not true allergy. Considering multiple outcomes can create a multiplicity issue when formal hypothesis tests are performed, because the chance of at least one false-positive finding can increase across tests. Whether any multiplicity adjustment or hierarchy among outcomes was planned is not reported in the registry record.

The record lists zero analyses and does not report outcome estimates, p-values, or confidence intervals. Therefore, there is no reported inferential result from which to assess multiplicity adjustments or selective emphasis. The statistical analysis plan is not reported in the registry record.

Missing-data procedures are also not reported. The record does not state whether every participant completed the survey, whether allergy histories or reaction details were incomplete, or how missing or ambiguous information was handled. It does not describe an analysis population, such as whether outcomes were based on all enrolled participants or only records with classifiable reactions. These details matter because incomplete symptom or timing information could affect whether an allergy entry meets the operational definition.

It is also not reported whether the allergy entries were reviewed by one or more assessors, whether disagreements were resolved, or whether classifications were checked for consistency. These are methodological details rather than evidence that any specific problem occurred. Without the analysis and missing-data information, the degree to which the results may depend on classification or completeness decisions cannot be evaluated.

11. Safety Results

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

Deaths

Other (non-serious) adverse events

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

The registry lists a medication-allergy group with 250 at risk for each safety category. It reports zero serious adverse events, zero other adverse events, and zero deaths. These are the recorded safety figures for the group.

A zero count means that no events were recorded in the registry’s summary for that category. It does not establish that the underlying risk is zero, nor does it show that the survey or an allergy classification caused or prevented an event. The record does not report additional detail about event definitions, collection procedures, follow-up duration, or attribution. Those details are not reported in the registry record.

These safety summaries should also be kept separate from the primary endpoint. The primary outcome concerns the number of allergy entries meeting a reaction definition, whereas the safety figures concern adverse events and deaths. The registry’s zero safety counts do not provide the missing primary outcome count or explain how allergy entries were classified.

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

This study addresses how medication allergies recorded in electronic medical records are characterized among patients presenting for surgery. It describes an approach that combines record identification with a participant survey about symptoms that prompted allergy listings. Its primary outcome definition makes clear which reaction types and timing qualify as a true allergy consistent with an IgE-mediated reaction for this study.

The record does not report the numeric result for that primary outcome or for the secondary categories. Consequently, it does not show how often listed allergies met the study definition, how precise any estimate was, or how the categories compared. The enrollment and allergy-entry counts describe the study population and data structure; they are not results for the primary outcome.

The study is not reported as a randomized comparison and has no comparator group in the record. It therefore cannot establish whether one intervention is better than another. Nor does the record demonstrate that a particular allergy classification changed perioperative decisions or outcomes. The stated aim of assessing potential relevance to perioperative care should be understood as the study’s purpose, not as a reported finding.

More generally, a reaction history classified using symptom and timing criteria is not identical to proof of a biological mechanism. The registry names the intended category as consistent with an IgE-mediated reaction, but it does not report a diagnostic validation study or confirmatory testing. The classification should therefore be interpreted according to the operational definition stated in the record.

The appropriate conclusion is limited: the registry describes a completed survey-based evaluation, its target population, and its primary classification rule. The numeric outcome and important analysis details are not reported in the registry record, so the magnitude, precision, and broader implications of the findings cannot be determined from these registry entries.

13. Why This Trial Matters Statistically

Medication allergy entries are not merely labels in a record; the study’s stated rationale is to examine the symptoms behind those entries and their potential relevance to perioperative care. Statistically, that question depends on defining what is counted and keeping the unit of analysis clear. This record specifies an allergy-level primary outcome and notes that some participants contributed multiple allergy entries, an important distinction for describing and analyzing the data.

The study also illustrates why a transparent operational definition matters. The primary classification uses reaction type and a time window after a dose. That definition gives readers a basis for understanding what the endpoint represents, while also making clear that classification depends on the information available about symptoms and timing. Whether those data were complete and consistently assessed is not reported.

The registry’s stated purpose is descriptive and concerns clinical decision-making context, not treatment efficacy. That makes the lack of a comparator consistent with the question as recorded, but it also limits what can be inferred about consequences of any particular approach. A useful descriptive study still requires reported outcome values, denominators, and uncertainty to show what was observed and how precisely it was estimated.

Here, the record includes enrollment and allergy-entry counts but not the numeric results for the primary or secondary outcomes. It lists zero analyses and does not report statistical methods or missing-data procedures. Those omissions prevent a quantitative assessment of the classification findings and highlight the distinction between a well-defined research question and a fully interpretable reported result.

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 of the registry record for interpreting this study is that it does not report numeric results for the primary or secondary outcomes. The primary endpoint is defined, but its count is unavailable, as are estimates of precision. The record therefore does not permit a quantitative assessment of the main classification question.

The registry describes participants who had a medication allergy listed in their electronic medical record and who presented for surgery. It does not report the recruitment method, eligibility details beyond the listed allergy status, or the characteristics of people who did not participate. The extent to which the enrolled group represents other patients or settings is not reported in the registry record.

Multiple allergy entries may come from one participant: the record reports 301 medication allergies among 250 participants. The analytic handling of this repeated-observation structure is not reported. Nor are the completeness of symptom and timing histories, classification procedures, assessor agreement, or handling of ambiguous entries. These omissions make it difficult to judge the reliability and uncertainty of the intended allergy categories.

The record lists three outcomes and zero analyses, but does not describe a statistical analysis plan, missing-data rules, analysis population, or multiplicity approach. It also does not report whether the study evaluated actual changes in perioperative decisions or patient outcomes. Thus, its stated relevance to perioperative care is a purpose rather than a demonstrated effect. These limitations concern what is available in the registry record and do not establish that the study itself lacked additional procedures or analyses.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Preoperative Survey to Evaluate Patient Allergy — NCT05670756.
• Registry record last updated 2024-10-15; status last verified 2024-10.
• Results first posted 2024-10-15.
• 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.

18. Record Summary

NCT05670756 is a completed survey study sponsored by Nationwide Children's Hospital, with enrollment listed as 250. The record describes identifying medication allergies in electronic medical records and asking participants about the symptoms that prompted those listings, using a REDCap survey on an iPad during the visit.

The primary outcome is the number of listed medication allergies meeting a definition based on specified reaction types within 6 h of a dose. The record states that 250 participants reported 301 medication allergies because some had multiple allergies. It lists two secondary allergy categories, but numeric results for all outcomes are not reported in the registry record.

The record does not describe a randomized comparator, and it lists zero analyses. Statistical methods, missing-data handling, and the analysis population are not reported. Safety summaries list zero serious adverse events, zero other adverse events, and zero deaths in the medication-allergy group.