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 Correlation of Spinopelvic Movement With Lateral Radiographs (NCT05117229), a na na study. The primary outcome is Pelvic Tilt (PT).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05117229 |
| Phase | NA |
| Condition | Spinopelvic Relationships as They Relate to Total Hip Arthroplasty's |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 40 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Mayo Clinic |
| Results posted | Yes |
2. Clinical Question
Population
People being considered for surgical orthopedic surgery who have a lateral sit-to-stand radiograph. The registry lists enrollment as 40. More detailed eligibility criteria and participant characteristics are not reported in the registry record.
Intervention
A MetaWear sensor is added to the lateral sit-to-stand radiograph. The study description says the sensor measures spine and pelvic movements. Further details about sensor placement, operation, or data processing are not reported in the registry record.
Comparator
No separate comparison group is described. The registry lists a single-group model and does not specify a control arm. Although the brief summary describes comparing the sensor with radiographs, the exact comparison and its analysis are not reported in the registry record.
Primary question
The primary measure is baseline pelvic tilt, recorded in degrees. The registry describes the study as assessing spine motion prior to total hip arthroplasty, but the precise primary hypothesis or criterion for evaluating agreement or association is not reported in the registry record.
In plain terms, the study concerns whether a wearable sensor can capture information about pelvic and spinal movement while a person completes a sit-to-stand movement for lateral radiographs. The registry identifies pelvic tilt as the primary endpoint, but it does not report a result for that endpoint. It also does not give a numerical estimate of the relationship between sensor readings and radiographic measurements. Therefore, the clinical question can be described from the study rationale and design, but the posted results do not establish how closely the measurements correspond, how variable they are, or whether the sensor adds information beyond the radiographs.
3. Trial Design
This is a completed, single-group study registered as NCT05117229, titled “Correlation of Spinopelvic Movement With Lateral Radiographs.” The official title specifies assessment of spine motion prior to total hip arthroplasty. The registry lists Mayo Clinic as sponsor, enrollment as 40, and the study period as starting 2021-12-01 with primary completion on 2023-01-19. Its status is COMPLETED.
The intervention is a MetaWear Sensor, classified as a device. The arm description states that participants being considered for surgical orthopedic surgery have a sensor added to their standard-of-care lateral sit-to-stand radiograph. The registry lists a single-group model and does not describe random allocation or masking beyond “NONE.” There is no separate control arm described, so this is not a randomized comparison. Results from this design, if reported, would need to be interpreted as measurements from the studied group rather than as a treatment effect against a concurrent control.
The brief summary says the research compares a novel pelvic MetaWear sensor, which looks at spine and pelvic movements, when taking lateral sit-to-stand radiographs. However, the registry record does not specify exactly which sensor and radiograph quantities were compared, the statistical definition of correlation or agreement, or whether repeated measurements were taken. The registry lists three outcome measures, but does not provide their results in the information summarized by this record. No analysis is listed. Details such as eligibility criteria, recruitment procedures, study sites, protocol deviations, and analysis populations are not reported in the registry record.
The registry lists the phase as NA. This is a device study, and the record does not state a drug-development phase. The dates and completion status describe the registered study timeline; they do not by themselves establish when every participant was assessed or when the analysis was completed.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | MetaWear Sensor on Radiograph |
|---|---|
| STARTED | 40 |
| COMPLETED | 40 |
| NOT COMPLETED | 0 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | MetaWear Sensor on Radiograph |
|---|---|---|
| Participants analysed | 40 | |
| Age, Continuous | years | 62.6 (SD 18.1) |
| Sex: Female, Male: Female | Participants | 26 |
| Sex: Female, Male: Male | Participants | 14 |
| Race and Ethnicity Not Collected | Participants | — |
| Region of Enrollment: United States | participants | 40 |
| Body Mass Index (BMI) | kg/m2 | 31.0 (SD 6.3) |
6. Primary Endpoint
The registry lists the primary outcome as Pelvic Tilt (PT), measured over Baseline.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | degrees |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is pelvic tilt (PT), a continuous measure reported in degrees at baseline. The registry defines PT as a position-dependent parameter: the angle between a line from the midpoint of the sacral endplate to the center of the bifemoral heads and the vertical axis. It is described as recorded by the MetaWear sensor.
Pelvic orientation changes with body position, so a measure tied to position can characterize one aspect of spinopelvic posture during the movement of interest. In general, continuous measurements such as an angle can be summarized by a mean and a measure of dispersion. The registry specifies the mean as the endpoint parameter and standard deviation as the dispersion measure. The mean describes the central value in the measured group; the standard deviation describes how spread out individual measurements are around that mean.
The endpoint is relevant to the study’s stated focus on spine and pelvic movement in people being considered for total hip arthroplasty. However, the registry record does not report the baseline mean or standard deviation, nor does it provide a numerical comparison between sensor readings and radiographs. The endpoint definition also does not by itself establish whether the sensor’s readings are accurate, reproducible, or clinically useful. Those interpretations would require results and supporting methodological details that are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies pelvic tilt at baseline as the primary outcome, but a numerical result for that endpoint is not reported in the registry record. In particular, no mean or standard deviation is available in the record, and no estimate of association or agreement between MetaWear sensor measurements and radiographic measures is reported. There are also no analysis results listed. As a result, the posted information does not permit a quantitative conclusion about the observed pelvic tilt or the relationship between the two measurement approaches.
The study is described as a single-group assessment, not a randomized comparison. That distinction matters. A single-group measurement study can describe values within the participants assessed and can potentially examine how different measurement methods relate. It cannot, on its own, estimate a comparative treatment effect between independently assigned groups. The record does not provide the precise comparison method, so it is not possible to tell whether the intended evaluation concerned correlation, agreement, change, or another measurement property.
General statistical interpretation: a mean is a summary of the center of a continuous distribution, while a standard deviation describes its variability. Neither quantity alone gives the full distribution of individual values. An association measure, if one were reported, would describe how measurements vary together; it would not automatically show that the two methods give interchangeable readings. Agreement addresses whether methods yield sufficiently similar values, which is a different question from whether their values move together. The registry does not report the statistic or criterion used to address either question.
Uncertainty also cannot be assessed from the registry information available. A confidence interval, if reported, would express the precision of an estimate under the assumptions of its analysis. No confidence interval, p-value, or other inferential result is reported. Without an estimate and its uncertainty, the result cannot be judged for magnitude or precision. The listed enrollment of 40 is not a substitute for an outcome estimate and does not reveal how many participants contributed usable baseline measurements.
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 between two arms, and a normal approximation. These are illustrations, not evidence that the study used a two-arm design. No resulting sample-size figures are available in this record, and the registry does not report the study’s own sample-size justification. Such planning calculations must not be interpreted as observed power or as evidence that an outcome was detected.
Accordingly, the defensible reading is descriptive: the registry documents a completed single-group sensor study, names pelvic tilt as its primary measure, and lists safety counts. It does not report the primary outcome values or the analyses needed to assess the measurement relationship. This is absence of reported numerical results in the registry record, not evidence that the measurements were equal, different, precise, imprecise, or clinically meaningful.
9. Statistical Methods Explained
General statistical explanation: the methods needed to interpret a continuous measurement study depend on the question being asked. Describing the typical value, assessing variability, measuring association, and evaluating agreement are related but distinct aims. The registry specifies a mean and standard deviation for the primary endpoint, but it does not report the analysis used to compare sensor and radiographic measures or provide estimates from that analysis.
What do the mean and standard deviation describe?
For a continuous endpoint such as pelvic tilt in degrees, the mean is the arithmetic center of the observed measurements. The standard deviation describes how dispersed measurements are around that center. A small or large standard deviation is meaningful only in the context of the endpoint, measurement procedure, and population; it should not be interpreted as a measure of accuracy. The registry indicates that the primary endpoint uses these summaries, but its numerical mean and standard deviation are not reported in the registry record.
These summaries also do not tell the full story of a distribution. A mean can be influenced by unusually high or low observations, and the standard deviation does not show whether values cluster unevenly or contain outliers. General statistical practice may use plots or additional summaries to examine distribution shape, but the registry record does not report those details for this endpoint. No conclusion about skewness, outliers, or measurement range can be drawn from the endpoint definition alone.
How are association and agreement different?
General statistical explanation: correlation measures the extent to which two measurements vary together. A strong correlation does not necessarily mean the measurements have similar numerical values. For example, one method could consistently give higher readings than another while preserving the same ordering of participants. Agreement methods instead examine how close paired measurements are and whether differences show systematic patterns. The exact approach depends on the study question and design.
The study title uses the word “Correlation,” while the brief summary refers to comparing the sensor with radiographs. Those descriptions do not identify a particular statistic or define an acceptable level of agreement. The registry record does not report the paired data, method-comparison analysis, prespecified criterion, or result. Consequently, it is not possible to tell whether the study evaluated association, agreement, or both, nor how any observed relationship should be quantified.
Why does the study structure matter?
This record describes a single-group model without a separate control arm. For a measurement study, participants may contribute readings from more than one method, but the record does not say precisely how measurements were paired or whether multiple readings were collected. If paired readings are analyzed, the analysis should account for their within-person relationship rather than treating them as independent observations. That is a general principle; the registry does not report whether or how it was applied.
The absence of random allocation means the study is not a randomized comparison of treatment groups. Randomization is not required for every measurement-method question, but design and analysis still need to match the intended inference. The record does not state whether the sensor result was compared with a reference standard, whether assessors were blinded to other readings, or how measurement quality was checked. These details are not reported in the registry record, so they cannot be assumed.
What would uncertainty estimates add?
General statistical explanation: an estimate is more informative when accompanied by an uncertainty measure. A confidence interval gives a range of values compatible with the data and analysis assumptions at a stated confidence level. Its width conveys precision: wider intervals indicate less precision than narrower intervals. A p-value addresses compatibility with a specified null hypothesis under a statistical model; it does not measure clinical importance, prove a hypothesis, or show that methods agree.
No confidence interval, p-value, or numerical effect estimate for pelvic tilt or the sensor-radiograph relationship is reported in the registry record. Therefore, neither the size nor the precision of any estimated relationship can be evaluated. The enrollment listing alone cannot supply that missing information, because precision also depends on the variability of the measurements, the analysis, and the number of usable observations.
How should the planning assumptions be read?
The registry includes assumptions for planning illustrations: two-sided significance level 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of an observed effect. It notes that non-time-to-event illustrations are expressed as participants per arm, while time-to-event illustrations use a total event count. These assumptions describe hypothetical planning calculations, not the design of the single-group study. The registry does not report resulting sample-size values or the study’s own design justification. The illustrations are not observed power and do not establish the sensitivity of this completed study.
General statistical explanation: planning calculations depend on an assumed effect size and variability, as well as the planned analysis and error rate. If an assumed effect is too optimistic, a planned study may be less informative than expected; if it is conservative, the calculation may imply a larger study. Those general considerations cannot be applied numerically to this record because the relevant result values and the study-specific planning rationale are not reported.
Overall, the registry specifies the endpoint summary and gives generic planning assumptions, but does not provide the methods or estimates required to reproduce or fully assess the primary analysis. Details about data handling, model choice, assumptions checks, confidence intervals, and sensitivity analyses are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists three outcome measures and identifies pelvic tilt as the primary endpoint. It does not report the other outcome definitions or their results in the information summarized in this record. The number of listed outcomes alone does not establish how many formal statistical tests were performed; the registry lists no analyses.
General statistical explanation: when multiple hypotheses are tested, the chance of at least one false-positive finding can increase if each test is interpreted independently. Analysis plans may address this through a prespecified hierarchy, adjustment, or a clearly exploratory interpretation. Which approach is appropriate depends on the questions and design. The registry record does not report a multiplicity strategy, so no adjustment or testing hierarchy can be assumed.
Missing-data methods and analysis populations are also not reported in the registry record. It is not stated whether all participants with a measurement were included, how missing measurements were handled, or whether exclusions occurred. The enrollment listing of 40 does not establish the number with evaluable primary-endpoint data. No imputation method, complete-case approach, or sensitivity analysis is specified in the record.
These omissions limit assessment of how the analyses were defined and how robust any result would be to missing data or multiple testing. Because no analysis results are listed, it is not possible to determine whether these issues affected any reported estimate.
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 |
|---|---|---|---|
| MetaWear Sensor on Radiograph | 0 | 40 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| MetaWear Sensor on Radiograph | 0 of 40 |
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 |
|---|---|
| MetaWear Sensor on Radiograph | 0 of 40 |
The registry lists one group, MetaWear Sensor on Radiograph. For that group, 40 are listed as at risk for serious adverse events and 0 as affected; for other adverse events, 40 are listed as at risk and 0 as affected. The death count is 0. No serious adverse-event terms are listed.
These counts describe what is recorded in the registry; they do not establish that no adverse events occurred outside the categories or reporting period captured by the record. The registry information does not provide event definitions, the safety observation window, severity grading, relatedness assessments, or details of how events were collected. It also does not give a comparison group. Therefore, the counts cannot support a comparative safety estimate, and the zero counts should not be read as proof of absence of risk.
General statistical explanation: an observed count of zero is a description of the recorded data, not a guarantee that the underlying event probability is zero. Interpretation depends on the number observed, duration of observation, completeness of reporting, and event ascertainment. Those details are not reported in the registry record. The appropriate reading is limited to the posted counts and the reporting limitations.
12. What the Result Does, and Does Not, Mean
The record documents a completed study evaluating a MetaWear sensor alongside lateral sit-to-stand radiographs in a single group. Pelvic tilt, measured in degrees at baseline, is identified as the primary endpoint. The study’s stated purpose concerns sensor measurement of spine and pelvic movement. These details establish the topic and broad design, but they do not provide the primary outcome result.
The numerical mean and standard deviation for pelvic tilt are not reported in the registry record. Nor are numerical results for correlation, agreement, or another comparison between sensor readings and radiographs. There is no reported estimate with which to assess the magnitude or precision of a measurement relationship. Thus, the posted results do not show how close the methods were, whether they tracked together, or how variable the measurements were among participants.
General statistical explanation: a measurement may be associated with another measurement without agreeing closely enough for the two to be interchangeable. Likewise, a group mean does not describe every individual reading. Assessing a method’s usefulness ordinarily requires evidence matched to the intended purpose, such as repeatability, agreement with a reference, or ability to measure a relevant feature. The registry record does not report enough results or methodological detail to judge those properties.
The single-group design also does not establish a treatment effect. The study is not described as a randomized comparison, and it has no separate control group in the record. It should therefore be read as a measurement-focused study rather than as evidence that an intervention changes a clinical outcome. No clinical outcome effect is reported.
The adverse-event entries record zero affected participants for serious and other adverse events, and zero deaths. These are registry counts, not proof that risk is absent; event definitions and observation details are not reported. Overall, the record supports a description of the study’s purpose, sensor, endpoint, and listed safety counts. It does not support a conclusion about measurement performance or clinical benefit.
13. Why This Trial Matters Statistically
This study matters statistically because it concerns how a wearable sensor might characterize movement during a clinical imaging procedure. Measurement questions are foundational: before a reading can inform later research or practice, its meaning, variability, and relationship to other measurements need to be understood. A study linking a sensor with lateral radiographs could address a methodological question, but only if the comparison and its results are clearly reported.
Pelvic tilt is defined as a position-dependent angle, so the conditions under which it is recorded are important to interpretation. The registry indicates that the sensor is added to a lateral sit-to-stand radiograph, but does not provide detailed measurement procedures or a numerical method-comparison result. Without those details, readers cannot distinguish a close match between methods from mere association, or determine whether observed variation reflects participants, positioning, or measurement processes.
The single-group design is appropriate to describe as a measurement study, not a randomized treatment comparison. This distinction prevents an overreach from measurement data to claims about treatment outcomes. In general, an informative report for this kind of question would make the estimand explicit, explain how paired readings were handled, quantify uncertainty, and state the limitations of the reference method and measurement process. Those details and numerical estimates are not reported in the registry record.
The record also illustrates why registry status and enrollment are not substitutes for outcome reporting. A study can be marked completed while the record available to readers lacks primary endpoint results and analysis details. That gap limits reproducibility and prevents evaluation of statistical precision. The central statistical importance is therefore both the study’s measurement focus and the need for complete reporting before its findings can be assessed.
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 main limitation for interpreting this study is that the numerical primary-endpoint result is not reported in the registry record. Although pelvic tilt is defined and the record specifies mean and standard deviation summaries, neither value is available. No quantitative result for the relationship between MetaWear measurements and radiographs is reported.
The comparison itself is not described in sufficient detail to identify its statistical target. The title refers to correlation, while the summary describes comparing the sensor with radiographs. The record does not say whether the intended question was association, agreement, repeatability, or another measurement property. It also does not specify the reference standard, the paired measurement procedure, or any acceptance criterion.
Further limitations include the single-group design and absence of a separate control arm. This is not a randomized comparison, so it cannot support a randomized treatment-effect interpretation. The registry does not report participant characteristics, detailed eligibility criteria, the number with usable primary-endpoint data, or how missing measurements were handled. The listed enrollment of 40 cannot answer those questions.
Analysis details are also not reported: there is no stated model, uncertainty estimate, multiplicity approach, or sensitivity analysis. The registry lists three outcome measures but no analyses. Safety reporting is limited to counts; event definitions and the observation period are not reported. These are limits of what can be concluded from the registry record and should not be filled in by assumption.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Correlation of Spinopelvic Movement With Lateral Radiographs — NCT05117229.
- Registry record last updated 2023-11-18; status last verified 2023-10.
- Results first posted 2023-11-18.
- 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
NCT05117229 is a completed, single-group study titled “Correlation of Spinopelvic Movement With Lateral Radiographs,” sponsored by Mayo Clinic. The registry lists enrollment as 40 and describes adding a MetaWear sensor to lateral sit-to-stand radiographs in people being considered for surgical orthopedic surgery. The study period is listed as starting 2021-12-01, with primary completion on 2023-01-19.
The primary endpoint is baseline pelvic tilt in degrees, summarized as a mean with standard deviation. Its numerical result and the analysis of the sensor-radiograph relationship are not reported in the registry record. The record lists zero serious adverse events, zero other adverse events, and zero deaths in the sensor group. Event definitions and observation details are not reported.
The registry describes planning assumptions for illustrations but does not report their resulting sample-size values or the study’s own statistical analysis. The available record therefore identifies the study question and broad design, but does not allow quantitative evaluation of the primary measurement result.