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 Pediatric Emergency Department Smartphone Otoscope Study (PED-Oto) (NCT02918773), a randomized na study. The primary outcome is Number of Antibiotic Prescriptions.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02918773 |
| Phase | NA |
| Condition | Acute Otitis Media, Acute Otitis Externa |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 22 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Emory University |
| Results posted | Yes |
2. Clinical Question
The study asks whether assigning participating clinicians to use a smartphone otoscope rather than a conventional otoscope is associated with a different number of antibiotic prescriptions for acute otitis media (AOM) in pediatric emergency department encounters. The primary measure concerns encounters in which a participating clinician diagnosed AOM, with prescription information obtained from children’s medical records. The registry specifies Month 6 as the primary outcome timeframe.
Population
Children seen in emergency department encounters by participating clinicians, where AOM was diagnosed. The registry summary describes the setting as two affiliated children’s hospital emergency departments.
Intervention
Participating clinicians assigned to the smartphone otoscope arm use that device for all otic examinations during the stated six-month period.
Comparator
Participating clinicians assigned to the conventional otoscope arm use a conventional otoscope for all otic examinations during the same stated period.
Primary question
At Month 6, how many encounters involving an AOM diagnosis had an antibiotic prescription recorded in each study arm? The registry record does not report the arm-specific primary outcome results or a comparison between them.
This is a question about prescribing in encounters, not a direct comparison of device accuracy or children’s clinical outcomes. The record also lists diagnoses of AOM and otitis externa, and clinician acceptability of the smartphone device, as secondary outcomes. Their results are not reported in the registry record.
3. Trial Design
The registry describes PED-Oto as a randomized, parallel-group study with no masking. The listed enrollment is 22. The study summary says that 20 volunteer clinicians would be randomly assigned to use either a smartphone otoscope or a conventional otoscope for all otic examinations over a six-month period. The enrollment figure and the summary’s clinician count describe different record entries; the registry does not explain their relationship further.
The setting is two affiliated children’s hospital emergency departments. The two arms are defined by the device assigned to clinicians: smartphone otoscope or conventional otoscope. The assignment is therefore described at the clinician level, while the primary outcome is measured in emergency department encounters involving children diagnosed with AOM. The registry record does not report how many clinicians or encounters were assigned to each arm for the primary analysis.
The study status is listed as completed. The recorded start date is 2016-10-15, and the primary completion date is 2017-04-15. These dates describe the registry record and do not supply outcome findings.
Because masking is listed as none, the study is recorded as unmasked. The record does not describe safeguards intended to limit the influence of clinicians’ knowledge of their assigned device, nor does it report whether outcome abstraction from medical records was blinded. Further details about sequence generation, allocation concealment, protocol deviations, or the analysis plan are not reported in the registry record. The posted design information therefore identifies the randomized comparison and its broad setting, but does not establish all operational details needed to assess conduct.
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: Study clinicians logged 1,502 encounters where otoscopes were used; 112 (7%) of encounters were excluded due to incomplete data or not meeting study inclusion criteria, for a total of 1390 encounters evaluated.
Overall Study
| Stage | Conventional Otoscope Encounters | Smartphone Otoscope Encounters |
|---|---|---|
| STARTED | 11 | 11 |
| COMPLETED | 11 | 11 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: This analysis includes emergency department encounters with children by a participating clinician where AOM was diagnosed.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: The attributes of the children seen in the pediatric emergency department who were examined by clinicians participating in the study are presented in the baseline analysis. Only minimal information was collected from the medical records regarding the baseline characteristics of these children..
| Characteristic | Unit | Conventional Otoscope Encounters | Smartphone Otoscope Encounters | Total |
|---|---|---|---|---|
| Participants analysed | 11 | 11 | 22 | |
| Age, Continuous | age in months of encounter subjects | 43.5 (SD 38.8) | 49.0 (SD 42.0) | 45.90 (SD 40.34) |
| Sex/Gender, Customized: Not collected | Emergency department encounters | 776 | 614 | 1390 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: United States | Emergency department encounters | 776 | 614 | 1390 |
| Reason for clinic visit: Fever | Emergency department encounters | 522 | 424 | 946 |
| Reason for clinic visit: Ear pain | Emergency department encounters | 106 | 96 | 202 |
| Reason for clinic visit: Congestion/runny nose | Emergency department encounters | 270 | 182 | 452 |
| Reason for clinic visit: Cough | Emergency department encounters | 365 | 274 | 639 |
| Reason for clinic visit: Other | Emergency department encounters | 338 | 317 | 655 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Antibiotic Prescriptions, measured over Month 6.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Emergency department encounters |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the number of emergency department encounters in which antibiotics were prescribed to treat acute otitis media. The registry says that prescription information was identified in medical records of children who received an otoscopic examination by a participating clinician. The primary analysis population is described as encounters with children seen by a participating clinician where AOM was diagnosed, and the stated timeframe is Month 6.
This endpoint focuses on prescribing activity among encounters meeting the AOM diagnosis description. It is not a count of all antibiotic prescriptions for every condition, and it is not itself a measure of diagnostic accuracy, symptom improvement, or safety. Counting prescriptions can describe a practice pattern, but interpreting an arm comparison would require the actual arm-specific counts and a clear account of the analysis population and method.
The registry record does not report the primary endpoint values, an effect estimate, uncertainty around an estimate, or a statistical test. It also does not give further details on how repeated encounters, missing records, or the definition of a prescription were handled. The intended endpoint and timeframe are stated, but the posted record does not allow the primary comparison to be quantified.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes that the trial was designed as a randomized comparison of smartphone and conventional otoscopes, and it describes a primary prescribing endpoint at Month 6. It does not post the values needed to determine how many qualifying AOM encounters had antibiotic prescriptions in either arm. Nor does it provide an effect estimate, confidence interval, or statistical test for that endpoint. As a result, the primary comparison cannot be interpreted quantitatively from the registry record.
This distinction matters: a stated outcome is not the same as a reported result. The record’s description of how prescription information was to be collected does not show what the collected data were. Likewise, the fact that the study is marked completed does not establish the direction, size, or precision of any difference between arms. The registry lists zero analyses, and no inferential results for the primary comparison are reported in the registry record.
The record does contain adverse-event figures for the two encounter groups. It reports zero serious events, zero other events, and zero deaths in each listed group. Those figures are useful as a description of what the registry posted, but they do not fill the gap in the primary endpoint results. They also should not be treated as evidence about the relative effects of the devices on prescribing or diagnostic decisions.
The secondary outcome descriptions include the number of AOM diagnoses, the number of otitis externa diagnoses, and clinician acceptability of the smartphone device. Their numerical results are not reported in the registry record. The posted information therefore supports a description of the planned comparison and recorded safety counts, not conclusions about whether the devices differed on the primary or secondary outcomes.
Any interpretation should also respect the measurement level. Clinicians were assigned to device arms, whereas the endpoint is described for encounters. Encounters handled by the same clinician may not be statistically independent. The record does not state whether the analysis accounted for this structure, or how many clinicians contributed encounters to each arm. Without those details and the outcome data, precision and the validity of any unadjusted comparison cannot be assessed.
The displayed tables, plots, and planning illustrations may help readers inspect other posted or derived material, but they do not replace an unreported primary result. Any planning illustration should be read as a hypothetical calculation under its stated assumptions, not as observed power or as evidence that the trial detected an effect. The main interpretive conclusion is limited: the registry describes a relevant randomized design, but does not report the primary outcome comparison.
9. Statistical Methods Explained
The registry identifies randomization, a parallel-group structure, and no masking. These terms describe broad features of the design, but they do not provide a full statistical analysis plan. The record does not report the randomization procedure, allocation concealment, the prespecified model, adjustment variables, or how uncertainty was to be summarized. The explanations below are general statistical context, not claims about methods used in this study unless those methods are explicitly described in the record.
What randomization contributes
In general, random assignment is intended to make comparison groups similar, on average, with respect to factors present before assignment. It can support causal interpretation when the assignment is implemented as planned and the analysis respects the unit of assignment. Here, the summary says volunteer clinicians were randomly assigned to use one of the two devices. The primary outcome, however, is described as a count of encounters. That means assignment and measurement occur at different levels: a clinician receives an assignment, and encounters handled by that clinician contribute outcome information.
In general, observations within a clinician may be related because they share the clinician’s habits and working context. An analysis that treats every encounter as independent can therefore understate uncertainty if it ignores clustering. The registry record does not report whether clustering was considered, how many clinicians were assigned to each arm, or how many qualifying encounters each clinician contributed. It is not possible to determine from the posted information whether the analysis handled this structure appropriately.
What a count endpoint means
The primary outcome is expressed as a number of encounters with an antibiotic prescription, within encounters where AOM was diagnosed. A count is different from a continuous measurement such as a laboratory value, and different from a binary outcome defined for each child or encounter. General approaches to count data may include methods that model event counts, sometimes with an allowance for the amount of observation or exposure. Which approach is suitable depends on how the data were collected and what contrast is intended.
Count data can have a variance that exceeds the mean, a feature commonly called over-dispersion. In general, allowing for over-dispersion can prevent uncertainty from being understated when counts are more variable than a basic count model expects. The registry record gives no dispersion estimate and does not identify a count model, an exposure offset, or any other model specification. The posted endpoint description alone is not enough to determine the appropriate analysis.
What an estimate and confidence interval would show
In general, an effect estimate would summarize the contrast between the two assigned-device groups on a defined scale. A confidence interval would describe the range of values compatible with the data and the statistical method under its assumptions. A narrow interval indicates greater precision than a wide interval, but an interval does not by itself resolve concerns about bias, measurement, or model choice. The registry record does not post an estimate or confidence interval for the primary endpoint, so the size and precision of any comparison are not available.
A p-value, if reported, would address compatibility between the observed data and a specified null model under assumptions. It would not measure the probability that the null hypothesis is true, nor establish practical importance. No primary endpoint p-value is reported in the registry record. It is therefore not appropriate to characterize the comparison as statistically significant or not statistically significant.
How to read planning illustrations
The planning assumptions described for the sample-size illustrations use a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation; the effect to detect is defined as a stated fraction of the observed effect. In general, such calculations illustrate the sample size associated with a chosen effect and assumptions. They do not describe the number of observations actually analyzed, and they are not observed power. The record does not report the trial’s own sample-size justification or planning rationale. Because the primary comparison itself is not reported, the illustrations should not be read as a substitute for an outcome estimate.
The record also does not identify a statistical method for the listed secondary outcomes or the clinician acceptability measure. Without those specifications and results, readers cannot assess how the secondary data were summarized, whether estimates were adjusted, or how uncertainty was handled. The registry’s design information is useful context, but a full evaluation of the analysis would require methods and results not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists the antibiotic-prescription count as the primary outcome and also describes outcomes concerning diagnoses of AOM and otitis externa, and clinician acceptability of the smartphone device. It does not report a multiplicity strategy, such as a hierarchy among outcomes or an adjustment for multiple statistical tests. The record lists no analyses, so there are no posted test results from which to judge how multiplicity was handled. This absence does not establish that no plan existed; the plan is simply not reported in the registry record.
Missing-data handling is also not reported in the registry record. The endpoint description says prescription information was found in children’s medical records, but it does not say how unavailable, incomplete, or ambiguous records were treated. It does not describe exclusions, imputation, or sensitivity analyses. Readers cannot determine whether all eligible encounters had complete outcome information.
The analysis populations are not fully specified beyond the description of encounters where AOM was diagnosed and a participating clinician performed an otoscopic examination. The record does not state whether analyses followed clinician assignment regardless of device use, how protocol deviations were handled, or whether any per-protocol population was used. It also does not report participant flow by arm or the number of clinicians and qualifying encounters included in an analysis.
These gaps limit interpretation of any potential comparison: multiplicity, missingness, and population definitions can affect estimates and their uncertainty. Since the primary outcome results themselves are not posted, these issues cannot be resolved by reviewing the registry record.
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 |
|---|---|---|---|
| Conventional Otoscope Encounters | 0 | 776 | 0.0% |
| Smartphone Otoscope Encounters | 0 | 614 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Conventional Otoscope Encounters | 0 of 776 |
| Smartphone Otoscope Encounters | 0 of 614 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Conventional Otoscope Encounters | 0 of 776 |
| Smartphone Otoscope Encounters | 0 of 614 |
The registry lists two encounter groups for adverse events: conventional otoscope encounters and smartphone otoscope encounters. For the conventional group, 776 are listed as at risk, with 0 serious events, 0 other events, and 0 deaths. For the smartphone group, 614 are listed as at risk, with 0 serious events, 0 other events, and 0 deaths. These are the posted counts, not a comparison of rates.
The figures are presented for encounter groups, so they should not be read as counts of individual children or clinicians. The registry record does not explain the event definitions, ascertainment process, observation period for these safety entries, or whether the figures refer to all encounters or a more restricted set. It also does not describe whether any events were judged related to an otoscope.
Zero reported events means that no events are listed in these registry fields; it does not establish that no unrecorded event occurred or that the devices have no safety concerns. The at-risk counts and event counts should be interpreted as a limited registry summary. They do not provide the missing prescribing results and should not be used to infer a difference in the primary endpoint.
12. What the Result Does, and Does Not, Mean
The posted record allows readers to identify the study’s central comparison: clinicians were assigned to use a smartphone or conventional otoscope, and the primary endpoint concerns antibiotic prescriptions in pediatric emergency department encounters diagnosed as AOM at Month 6. It also gives the broad setting, the study status, and adverse-event counts. These are meaningful features for understanding what the trial set out to examine.
However, the record does not report the primary outcome values or a between-arm estimate. It therefore does not show whether prescription counts differed, how large any difference was, or how precisely a difference could be estimated. The record also does not report the numerical results for the listed secondary outcomes. It cannot support a conclusion about comparative prescribing, diagnostic patterns, clinician acceptability, or the accuracy of either device.
The trial’s completed status is not a result. Nor does randomization alone establish what the data showed. A reader would need the outcome data, a clearly described analysis population, and methods that account for the clinician-level assignment and encounter-level measurement to evaluate the comparison. None of that can be reconstructed from the posted record without guessing.
The zero event counts are a separate descriptive entry and do not answer the primary question. Similarly, planning illustrations are hypothetical calculations based on stated assumptions; they are not observed power, and they cannot establish an effect when the primary results are absent.
The appropriate reading is therefore bounded. The registry documents a randomized, unmasked, parallel comparison in pediatric emergency departments and defines a prescribing endpoint. It does not provide enough result information to determine the direction, magnitude, or precision of the primary comparison. No conclusion about whether one device changed prescribing or improved diagnosis follows from the posted information alone.
13. Why This Trial Matters Statistically
This trial is statistically interesting because its assignment and outcome occur at different levels. The registry summary describes clinicians as the units randomly assigned to a device, while the primary outcome is a count across encounters involving children diagnosed with AOM. That structure raises a general design and analysis issue: encounters managed by the same clinician may share patterns, so a suitable analysis may need to account for clustering. The record does not say whether it did.
The endpoint also illustrates why the population definition matters. The primary measure concerns prescriptions among encounters in which AOM was diagnosed, rather than all emergency department encounters. The number and composition of qualifying encounters can affect the interpretation of a count. The registry describes the endpoint and timeframe, but does not post the counts or the analysis denominator by arm.
Randomization is valuable, but it does not remove the need to report how assignment was conducted, how the data were analyzed, and how uncertainty was quantified. The lack of posted outcome estimates means readers cannot assess precision or distinguish a meaningful pattern from chance variation. The absence of secondary results and a stated multiplicity approach further limits what can be learned about the broader set of questions in the record.
For biostatisticians and clinical researchers, the record highlights the importance of transparent reporting across design, unit of assignment, outcome unit, analysis populations, and results. In this case, the design and endpoint are identifiable, but the registry’s posted information does not connect them through a reported analysis. That gap is central to interpreting the study statistically.
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 primary limitation for interpreting this specific trial is that the registry record does not report the primary endpoint results. No arm-specific prescription counts, effect estimate, confidence interval, or test result are posted. The secondary outcome results are also not reported in the registry record. Consequently, the page can describe the question and design, but cannot assess the size or precision of the observed comparison.
The design description leaves several details unresolved. The summary refers to volunteer clinicians being randomized, while the listed enrollment is 22; the registry does not explain the relationship between these entries. It also does not report the number of clinicians or qualifying encounters in each arm. Because assignment is described for clinicians and the endpoint is measured in encounters, missing detail about the analysis of within-clinician clustering is especially relevant.
Masking is listed as none, and the record does not describe whether medical-record outcome abstraction was blinded. The protocol, allocation procedures, adherence to assigned device, departures from assignment, and analysis plan are not reported in the registry record. The endpoint description does not specify how incomplete or ambiguous records were handled, and missing-data procedures are not reported.
The record lists adverse-event counts but does not provide event definitions or further ascertainment details. It does not report a multiplicity strategy for the primary and secondary outcomes. These are limitations of the available registry information; they should not be taken as proof that the underlying study did not address these issues. They do, however, constrain what can be concluded from the posted record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Pediatric Emergency Department Smartphone Otoscope Study (PED-Oto) — NCT02918773.
- Registry record last updated 2018-07-13; status last verified 2018-06.
- Results first posted 2018-07-13.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
PED-Oto is listed as a completed, randomized, parallel-group study with no masking. The registry describes a comparison of smartphone and conventional otoscopes in two affiliated children’s hospital emergency departments. Its summary says volunteer clinicians were assigned to use one device for all otic examinations over a six-month period. Listed enrollment is 22.
The primary outcome is the number of emergency department encounters with an antibiotic prescription for AOM, assessed at Month 6 among encounters where AOM was diagnosed. The registry record does not report the primary result or an analysis comparing arms. It also lists outcomes for AOM diagnoses, otitis externa diagnoses, and clinician acceptability, without numerical results reported in the registry record.
The adverse-event fields list 0 serious events, 0 other events, and 0 deaths in each encounter group. The record does not report a statistical analysis plan, missing-data procedures, or a multiplicity strategy. The available information defines the study question and broad design, but does not support a quantitative interpretation of its primary comparison.