Otteroo Case Series: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Otteroo Case Series (NCT03502265), a na na study. The primary outcome is Change in Alberta Infant Motor Scale.

2. Clinical Question

The clinical question concerns infants with or at risk for, or concern about, developmental delay. The registry describes an evaluation of Otteroo use as an adjunct to standard care, with infant motor development assessed over time. It is a single-group case series, not a randomized comparison of Otteroo with a separate control group. The record therefore frames a question about change during a sequence of care periods, rather than a direct estimate of the difference between two independently assigned treatments.

The stated primary outcome is change in Alberta Infant Motor Scale percentile, measured at weeks 0 and 12. The description says that a positive change means the percentile increased and a negative change means it decreased. The record gives no individual values, group summary, or analysis result for this change. It therefore does not establish whether the observed children’s percentiles rose, fell, or stayed the same.

That distinction matters: a within-child trajectory can describe what happened to participants during the study periods, but it cannot by itself separate change associated with Otteroo use from change that might occur with standard care, development over time, or other influences. The registry record does not report a like-for-like control comparison.

3. Trial Design

This is a completed, single-group study described as a case series. The registry lists enrollment of 4 and one Otteroo adjunct arm. Allocation is recorded as NA, masking as none, and the study model as single group. The record does not describe random assignment or blinding. Its stated design is a single-subject research design in which measures are collected across successive periods.

During the first 4 weeks, participants receive standard care as the baseline period. The next 4 weeks combine standard care with Otteroo use. The final 4 weeks are described as a reversal or retention period with standard care. The primary outcome is defined as change in Alberta Infant Motor Scale percentile from week 0 to week 12. Although the record describes measurements across the phases, it does not report the measurements at each time point or explain how the phase-specific observations were analyzed.

The intervention description presents Otteroo as a floatie that supports an infant or young child with their head above water and body in water. The rationale is that it may serve as a tool for exploring movement and body control before locomotion develops. This describes the study’s rationale; it is not evidence that a particular developmental effect occurred.

The study is listed as completed. Its recorded start date is 2018-04-03, and its primary completion date is 2019-09-01. The sponsor is the University of Southern California. The phase is recorded as NA. These registry entries describe the study record and do not supply an outcome analysis, a protocol rationale for the enrollment, or further design information. A sample-size justification 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

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 Alberta Infant Motor Scale, measured over weeks 0 and 12.

The primary endpoint is change in Alberta Infant Motor Scale percentile from week 0 to week 12. The registry describes the scale as an observational measure of motor skills and expresses the endpoint in change in percentile. Its stated full percentile range is 0-100%. A change of 0 means no change in percentile score. The description says that a change of 100 represents movement from 0% to 100% or from 100% to 0%, the maximum possible change in percentile score. Positive values indicate an increased percentile; negative values indicate a decreased percentile.

A percentile expresses a child’s position relative to a reference distribution, rather than a direct count of newly acquired skills. A change score gives a concise way to describe how that position differs between the two specified assessments. As a general statistical point, an endpoint should be interpreted according to its scale and the assessment times defined in the study; a change score alone does not show the full pattern of measurements between those times.

The endpoint is relevant to the stated question because the study rationale concerns infant movement and motor development. However, the registry record does not report the observed endpoint values, a mean change, the range of individual changes, or an uncertainty estimate. The measure’s definition and intended interpretation are available, but the result itself is not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The statistical information in the registry record is limited. It describes a single-group, single-subject research design and a change-score endpoint, but does not report a statistical analysis plan or any completed outcome analysis. The explanations below distinguish general statistical concepts from methods documented for this study.

What does a single-group design estimate?

In general, a single-group design observes outcomes in participants who pass through a sequence of conditions or periods. Repeated measurement can help describe each participant’s trajectory and can show whether observations differ across periods. It does not, by itself, provide the same protection against alternative explanations as a randomized comparison with a separate control group. Time, standard care, natural development, measurement conditions, and the intervention may coincide with changes in the observed outcome.

For this study, the registry describes a 4-week baseline period with standard care, a 4-week period with standard care and Otteroo, and a 4-week reversal or retention period with standard care. It also defines the primary change between week 0 and week 12. The record does not report whether the phase observations were summarized separately, whether trajectories were examined visually or statistically, or how individual and group-level information was combined. Those analysis details are not reported in the registry record.

What does a change score express?

In general, a change score is the later measurement compared with the earlier measurement for the same participant. Its sign and scale should be read according to the outcome definition. Here, the registry states that a positive change is an increased Alberta Infant Motor Scale percentile and a negative change is a decreased percentile. It describes the percentile range as 0-100% and states that 0 means no change in percentile score. These are interpretive definitions, not reported participant results.

A change score condenses two measurements into one value. It does not show the sequence of measurements between those assessment points, and it may not convey how much participants differ from one another. In general, presenting participant-level values alongside a group summary can make heterogeneity visible, particularly in a small case series. The registry record does not report those values or summaries.

What can a confidence interval tell a reader?

In general, a confidence interval describes the uncertainty around an estimated quantity under a statistical model and its assumptions. A narrow interval indicates greater precision than a wide interval, while an interval that includes a range of plausible values may leave substantial uncertainty about the magnitude or direction of an effect. An interval does not correct weaknesses in study design, remove bias, or establish that an observed change was caused by an intervention.

No confidence interval is reported for the primary endpoint in the registry record. Because no endpoint estimate is reported either, there is no interval to interpret. The sample-size planning illustrations are not a substitute for an uncertainty interval around observed study results.

What is the role of a significance test?

In general, a significance test evaluates how compatible data are with a specified statistical model and null hypothesis. A p-value is not the probability that a treatment works, nor does it describe the size or practical importance of a difference. Its interpretation depends on the design, analysis choices, data quality, and assumptions. It is best considered alongside an effect estimate and its uncertainty.

The registry record lists 0 analyses and does not report a p-value, test statistic, or analysis method for the primary outcome. A significance test should not be inferred from the endpoint definition or from planning calculations. No hypothesis-testing procedure is reported in the registry record.

How should the planning illustrations be understood?

The record describes planning illustrations based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It states that the effect to detect is a stated fraction of the observed effect. These assumptions describe the illustrations, not the case series’ actual design. The study itself is recorded as single group, with no randomized comparison and one arm.

In general, sample-size calculations ask how many participants a hypothetical design would require under chosen assumptions. Their output depends on the target effect, variability, error rate, allocation, and model. An illustration based on an observed effect is especially dependent on that effect estimate and should not be treated as a prospective design justification unless the record establishes that role. The registry says these are planning illustrations, not the trial’s own design. They are not observed power and do not show that the study had a particular probability of detecting an effect.

For time-to-event illustrations, the record states that counts refer to total events; other illustrations refer to participants per arm. Those conventions concern the planning material and do not alter the study’s one-group structure. The record does not report the study’s own sample-size justification, the assumed variability, or a prospective power calculation.

What does the registry not tell us about analysis?

The registry does not report a detailed statistical plan, a missing-data method, an analysis population, a method for handling repeated observations, or an adjustment strategy. It also does not report an interim analysis plan. These omissions mean that the analysis cannot be reconstructed from the registry entry. General statistical principles can explain how such methods work, but they cannot identify which methods were used in this study.

10. Multiplicity, Missing Data and Analysis Populations

The record lists one outcome measure and 0 analyses. It identifies change in Alberta Infant Motor Scale percentile as the primary outcome, but does not describe whether additional outcomes, secondary analyses, or multiple statistical comparisons were planned outside the registry entry. A multiplicity adjustment or strategy for controlling the chance of false-positive findings across multiple tests is not reported in the registry record.

Multiplicity is a general concern when many outcomes, time points, subgroups, or analytical choices are examined. The more opportunities there are to select a notable result, the more important it is to know what was prespecified and how results were interpreted. The registry describes observations over three successive periods and a primary assessment spanning weeks 0 and 12, but does not report the complete analysis plan or whether comparisons among the periods were formally tested. It would be inappropriate to assume that a particular multiplicity method was used or that no additional analyses occurred.

Missing-data information is also not reported in the registry record. The record does not state whether all planned assessments were completed, whether any observations were missing, how missing values were handled, or whether participants were included under a prespecified analysis population. These details matter because missing outcome data can change which participants contribute to a summary and can affect how representative the observed results are.

The enrollment count alone does not establish the number with a completed primary assessment. Nor does the registry’s record of 0 analyses establish that data were complete or that no analysis was conducted outside the registry. The posted entry does not provide enough information to assess those possibilities.

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’s safety figures list the Otteroo Adjunct group with 4 participants at risk for serious adverse events and 0 affected. For other adverse events, it also lists 4 at risk and 0 affected. Deaths are recorded as 0, and no serious adverse event terms are listed.

These figures describe what is recorded in the registry for this group. They should be read as recorded counts, not as proof that no adverse events occurred outside the reporting captured in the entry. The record does not provide event narratives, definitions beyond the serious and other categories, follow-up details, or an explanation of how events were collected and reviewed. It also does not report a separate comparison group for safety.

With a small single-group study, a count of 0 affected participants cannot establish that an event is impossible or characterize safety across a wider population. It also does not allow comparative estimates between Otteroo and another intervention. The appropriate reading is limited: the registry reports zero participants affected in the listed serious and other adverse-event categories and zero deaths among the listed group, while further safety details are not reported in the registry record.

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

The registry record establishes what the study set out to examine: change in Alberta Infant Motor Scale percentile from week 0 to week 12 among infants with or at risk for, or concern about, developmental delay, during a sequence that includes standard care and an Otteroo adjunct period. It also describes the intervention rationale and the intended baseline, intervention, and reversal or retention periods.

It does not report the outcome values or an analysis of them. As a result, the record does not show whether percentile scores increased, decreased, or remained unchanged, how much any change varied among participants, or how precisely a group-level change was estimated. It also does not provide a statistical test or confidence interval. No conclusion about the observed developmental change can be drawn from the endpoint definition alone.

The single-group structure is important to interpretation. Even if a change were reported, an uncontrolled sequence of observations would not isolate the effect of Otteroo from standard care, development over time, measurement variation, or other influences. The record does not describe randomization or a separate control arm, and its allocation is recorded as NA. This limits causal interpretation; it does not itself tell us whether participants changed or why.

The safety entry reports 0 participants affected by serious adverse events, 0 affected by other adverse events, and 0 deaths in the listed group. Those are registry counts, not a comprehensive guarantee of safety or a comparison against another group. The entry does not provide additional event details.

Accordingly, the most defensible conclusion is about the scope of the record, rather than a treatment effect: the study design and primary measure are described, but the primary result and its statistical uncertainty are not reported in the registry record. The planning illustrations are not trial results, do not represent observed power, and do not replace a report of the completed outcome analysis.

13. Why This Trial Matters Statistically

Statistically, this case series highlights the difference between measuring change and identifying its cause. Repeated observations across baseline, intervention, and reversal or retention periods can be informative about participant trajectories. The sequence described in the record offers a structure for observing how measurements vary over time. But because there is no separate control arm, the design cannot by itself distinguish intervention-related change from changes associated with time, standard care, development, or other influences.

The registry also illustrates why an endpoint definition is not an outcome result. It specifies the Alberta Infant Motor Scale percentile, the assessment points, and how positive and negative changes are interpreted. Those details help explain what a reported value would mean. Without participant values or an analysis, however, they do not reveal the direction, magnitude, or precision of change. A clear outcome definition and a report of the observed data are both needed for statistical interpretation.

A further lesson concerns the distinction between a study design and a planning calculation. The record describes sample-size planning illustrations using a hypothetical two-arm framework, while the case series itself has a single group. Planning calculations can help explore what a different design might require under stated assumptions, but they are not evidence of the completed study’s statistical power or results. They also cannot serve as the study’s own design justification when the registry identifies them as illustrations.

Finally, small case series can be useful for describing experiences and patterns that warrant careful follow-up, but their statistical interpretation depends on transparent reporting of individual outcomes, missingness, analysis choices, and uncertainty. Those elements are not reported in this registry entry. Its value is therefore in documenting the research question, design, and outcome definition while making clear how much remains unknown from the posted statistical record.

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.

Several limitations are specific to the information recorded for this study. Enrollment was 4, and the design has one group rather than a separate control arm. The record describes successive standard-care, Otteroo adjunct, and standard-care periods, but it does not provide the actual observations from those periods. It is therefore not possible to examine individual trajectories, compare changes across phases, or assess whether any pattern was consistent among participants.

The primary endpoint is defined as change in percentile between weeks 0 and 12, but no outcome value or analysis is reported. There is no estimate of group change, participant-level result, measure of variability, confidence interval, or test result. This prevents assessment of both the direction and precision of the outcome.

The record does not report the statistical analysis plan, sample-size justification, analysis population, handling of missing observations, or approach to repeated measurements. It also does not report whether assessments were completed for every enrolled participant. Without this information, the analysis cannot be reconstructed and the potential effects of missing data cannot be evaluated.

The absence of a like-for-like control comparison limits causal attribution. A change observed across the study periods could not be separated from the influence of standard care, development over time, measurement variation, or other factors using the design as described. The record does not report additional details that would resolve these limitations.

Safety reporting is similarly limited to counts: the record lists 4 at risk and 0 affected in each adverse-event category, with 0 deaths, but gives no event narratives or collection details. These are registry-reporting limitations; they should not be mistaken for evidence about unreported observations or analyses.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Otteroo Case Series — NCT03502265.
• Registry record last updated 2021-11-23; status last verified 2021-10.
• Results first posted 2021-10-27.
• 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

The registry record describes NCT03502265, Otteroo Case Series, as a completed single-group case series sponsored by the University of Southern California. Enrollment was 4. The recorded start date is 2018-04-03, and the primary completion date is 2019-09-01. Allocation is listed as NA, masking as none, and phase as NA.

The single arm combines standard care with Otteroo during a 4-week intervention period, preceded by a 4-week standard-care baseline and followed by a 4-week standard-care reversal or retention period. The primary outcome is change in Alberta Infant Motor Scale percentile from week 0 to week 12.

The registry reports no outcome analyses and does not report primary endpoint results. The safety entry lists 0 participants affected by serious adverse events, 0 affected by other adverse events, and 0 deaths among 4 at risk in the group. The record describes the study question and design, but does not report an analysis of developmental outcomes or additional details needed to assess its precision.