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 Development of Low Cost Devices to Increase Access to Treadmill Training (NCT02560506), a na na study. The primary outcome is Change in Locomotor Performance During Treadmill Walking.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02560506 |
| Phase | NA |
| Condition | Spinal Cord Injury |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 19 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Shirley Ryan AbilityLab |
| Results posted | Yes |
2. Clinical Question
Population
People with spinal cord injury were enrolled in a study of treadmill training. The registry record reports enrollment of 19 participants. It does not provide further eligibility details or a description of the characteristics of the enrolled participants, so the population represented by the results cannot be described more specifically from this record.
Intervention
The intervention was elastic-assisted treadmill walking. Participants trained on a treadmill with a low-cost pulley system made of rubber bands, described as Theraband, to assist therapists in advancing the limbs during gait training. The registry record does not report the training schedule, duration of individual sessions, or the amount of assistance used.
Comparator
No separate comparator group is reported. The study is identified as a single-group study, with allocation listed as not applicable. It therefore does not provide a like-for-like control comparison in which outcomes for one group can be contrasted with outcomes for another group receiving a different intervention or usual care.
Primary question
The primary outcome concerns change in treadmill speed, measured in meters per second, from baseline at 8 weeks. The clinical question is whether locomotor performance during treadmill walking changed over that period among participants receiving elastic-assisted treadmill training. The registry record gives the outcome definition but does not report the observed change or its uncertainty.
3. Trial Design
This completed study is registered as a single-group investigation of elastic-assisted treadmill walking for people with spinal cord injury. The registry lists enrollment of 19 participants. Allocation is marked not applicable, and the study is not described as a randomized comparison. Masking is listed as none. These design features mean that the primary outcome is framed as change within the study group, rather than as a contrast between separately assigned intervention and control groups.
The intervention description specifies treadmill training with a low-cost pulley system made of rubber bands. The device is intended to assist therapists in advancing participants’ limbs during gait training. The registry does not report the frequency or length of training sessions, the total intervention period, or details on how use of the device was standardized. Such operational details are not reported in the registry record.
The primary outcome is change from baseline in treadmill speed at 8 weeks, expressed in meters per second. It is described as a continuous measure summarized by a mean and standard deviation. Gait kinematics is listed as a secondary outcome, and the registry record identifies 3 outcome measures in total. It does not give numerical results for the primary or secondary outcomes.
The record gives a start date of 2008-01, a primary completion date of 2016-09, and a completed status. It does not report a statistical analysis for the outcomes: the record lists 0 analyses. Information about the planned analysis, the analysis population, or how missing measurements were handled is not reported in the registry record. The study design supports describing observed changes among participants, but without a reported comparison group it cannot isolate the intervention’s effect from other explanations for change over time.
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 | Elastic Assisted Treadmill Walking |
|---|---|
| STARTED | 19 |
| COMPLETED | 19 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: same as above
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 | Elastic Assisted Treadmill Walking |
|---|---|---|
| Participants analysed | 19 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 19 |
| Age, Categorical: >=65 years | Participants | 0 |
| Age, Continuous | years | 43 (SD 19) |
| Sex: Female, Male: Female | Participants | 6 |
| Sex: Female, Male: Male | Participants | 13 |
| Race and Ethnicity Not Collected | Participants | — |
| Region of Enrollment: United States | participants | 19 |
| peak treadmill speed | m/s | .64 (SD .26) |
6. Primary Endpoint
The registry lists the primary outcome as Change in Locomotor Performance During Treadmill Walking, measured over change from Baseline in treadmill speed at 8 weeks.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | m/s |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change in treadmill speed from baseline at 8 weeks. Speed is measured in meters per second and is intended to describe locomotor performance during treadmill walking. The registry record describes evaluation of treadmill speed before and after use of the device. A change measure focuses on how the recorded speed differs over time within the study group rather than comparing outcomes between randomized groups.
As a continuous outcome, treadmill speed can be summarized by a mean and a standard deviation. The mean describes the group’s average measurement or average change, while the standard deviation describes the spread of individual measurements around that mean. These summaries can help characterize both the direction and variability of observed changes, but they do not by themselves establish that a change was caused by the device.
The endpoint is relevant to the stated focus on locomotor performance during treadmill walking. However, the registry record does not report baseline or follow-up means, the mean change, its standard deviation, a confidence interval, or a statistical test. Consequently, the magnitude and precision of the primary outcome cannot be evaluated from the registry record. Gait kinematics is listed as a secondary outcome, but numerical results for it are not reported in the registry record either.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record defines a clear primary measurement: change in treadmill speed from baseline at 8 weeks, in meters per second. It also identifies the outcome as continuous and describes the intended summary as a mean with standard deviation. However, no numerical outcome findings are reported. There is no posted mean change, no baseline or follow-up value, and no standard deviation or other measure of uncertainty for the primary outcome. The direction, size, and precision of any change therefore cannot be assessed from the registry record.
The study is single-group, with no randomized or other comparison group described. Even if within-group change results were available, a before-and-after comparison alone would not distinguish the intervention’s contribution from changes over time, participants’ other care or activities, measurement variation, or other factors. This limitation is inherent to interpreting change without a comparator; it does not imply that any particular alternative explanation occurred in this study.
The record reports enrollment of 19 participants, but enrollment is not the same as the number with an observed primary outcome. The number contributing measurements at baseline and at 8 weeks, and the handling of any missing measurements, are not reported in the registry record. Without those details, the completeness of the outcome data cannot be judged.
The registry lists 0 analyses. It therefore does not report a statistical test, p-value, confidence interval, or adjusted estimate for the primary endpoint. A p-value, if available, would address compatibility of the observed data with a specified statistical model; it would not measure the size or clinical importance of an effect. A confidence interval would describe uncertainty around an estimate under its analysis assumptions. Neither can be interpreted without an estimate and its reported analysis.
Gait kinematics is named as a secondary outcome, but its specific results are not reported. The record does not provide enough information to assess whether outcome definitions or analysis choices were prespecified, or whether multiple outcomes or analyses affected interpretation. Overall, the registry record documents the study question, intervention, and primary endpoint, but does not provide the results needed to quantify observed changes or their uncertainty.
9. Statistical Methods Explained
The registry describes the primary endpoint as a continuous measure: change in treadmill speed from baseline at 8 weeks. The stated unit is meters per second, and the specified summary is a mean with standard deviation. These terms describe the type of outcome and a way to summarize it; they do not identify the analysis method actually used. No outcome analysis is reported in the registry record.
What a mean and standard deviation describe
In general, a mean is the arithmetic average of a set of measurements. For a change endpoint, it can represent the average within-participant change if changes are calculated for participants and then averaged. A standard deviation describes how dispersed the measurements are around their mean. It reflects variation among observations, not the precision of the mean itself. The registry record does not report either summary for this endpoint, so the amount of change and the variability among participants are not known from the posted results.
General statistical interpretation distinguishes variability in individual outcomes from uncertainty about a group estimate. A confidence interval is a range of values compatible with the data under a specified model and method. Its width is influenced by variability, sample size, and the analysis approach. It is not reported for the primary outcome in the registry record. Without a reported estimate and interval, readers cannot determine how precisely the change was estimated.
Within-group change and a comparator
General explanation: a within-group analysis compares participants’ measurements over time, while a comparative analysis evaluates the difference in outcomes between groups. This record describes a single group and does not identify a separate control group. A within-group change, even if reported, would describe what happened in the enrolled participants over the measurement period. It would not, by itself, separate an intervention effect from other influences or from natural variation over time. The record does not report whether a within-group statistical test was performed.
Analysis choices not reported
The registry record lists 0 analyses. It does not report whether the primary outcome was analyzed using a model, a paired comparison, or another approach. It also does not describe covariate adjustment, handling of outliers, assumptions checks, or a method for estimating uncertainty. These details are not reported in the registry record and should not be inferred from the endpoint’s mean-and-standard-deviation description.
General explanation: statistical models rely on assumptions about the data and the relationship being estimated. For example, some methods assume that observations or model residuals follow a particular distribution. If outcome variability is greater than a model expects, uncertainty estimates and tests can be poorly calibrated; methods that account for over-dispersion may be relevant in settings where it occurs. The registry record does not indicate that over-dispersion was assessed or that any particular model was used. This general point is not a claim about the treadmill-speed data in this study.
Planning illustrations
The registry’s planning assumptions describe an illustration using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They also describe detecting a stated fraction of an observed effect. These are planning assumptions, not a description of the study’s actual single-group design or its reported analysis. The illustration is not the trial’s design justification, and it is not observed power. Numerical sample-size results and the particular effect fraction are not reported in the registry record. Because the study has no reported comparator group or posted effect estimate, those planning assumptions do not establish how well this study was powered for its primary endpoint.
In general, a sample-size calculation estimates the number of participants needed under specified assumptions about the effect to detect, variability, significance level, and analysis. Changing those assumptions changes the planning result. Such calculations do not show that a study had a particular probability of finding a result after the data have been collected. The planning illustration associated with this record should therefore be read as hypothetical and distinct from the enrolled group of 19 participants.
Multiplicity and outcome selection
When several outcomes or analyses are examined, general statistical practice considers whether the chance of a misleading positive result is affected by making multiple comparisons. This record lists 3 outcome measures, identifies gait kinematics as a secondary outcome, and names treadmill-speed change as primary. It does not report a multiplicity adjustment, a hierarchy of secondary outcomes, or the analysis results. It is therefore not possible to determine from the registry record how multiple outcomes were handled or whether any adjustment was used.
10. Confidence Intervals for Each Arm
No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.
| Arm | Participants | Mean | Standard deviation | 95% CI for the mean |
|---|---|---|---|---|
| Elastic Assisted Treadmill Walking | 19 | 0.800 | 0.250 | 0.680 to 0.920 |
R code and output
arm <- c("Elastic Assisted Treadmill Walking")
n <- c(19)
m <- c(0.8)
sp <- c(0.25)
sd <- sp # posted standard deviations
for (i in seq_along(n)) {
se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}
CARM Elastic Assisted Treadmill Walking 19 0.800 0.250 0.680 0.92011. Multiplicity, Missing Data and Analysis Populations
The registry record identifies treadmill-speed change at 8 weeks as the primary outcome and lists gait kinematics as a secondary outcome. It also reports 3 outcome measures in total. It does not describe the other outcome measures in the record, provide a statistical analysis plan, or state whether multiplicity was addressed. Whether the analyses used a prespecified hierarchy or an adjustment for multiple comparisons is not reported in the registry record.
General explanation: evaluating several outcomes or conducting several tests can increase the chance of at least one apparently unusual result. A prespecified primary outcome can help focus interpretation, while multiplicity procedures can modify inference when multiple comparisons are planned. The registry’s designation of a primary outcome is useful context, but it does not establish what analyses were conducted or whether any statistical adjustment was applied.
The record lists 0 analyses and contains no numerical primary or secondary outcome results. It does not report the number of participants with measurements at each time point, reasons for missing measurements, or how missing data were handled. It also does not identify an analysis population, such as all enrolled participants or participants with complete measurements. These details are not reported in the registry record.
General explanation: missing outcome data can affect interpretation when participants with observed results differ from those whose measurements are unavailable. The impact depends on the amount and pattern of missingness and on the analysis assumptions. Since the record does not report outcome completeness or a missing-data method, the direction or extent of any such influence cannot be assessed.
12. 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 |
|---|---|---|---|
| Elastic Assisted Treadmill Walking | 0 | 19 | 0.0% |
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 |
|---|---|
| Elastic Assisted Treadmill Walking | 0 of 19 |
The registry’s adverse-event entry lists 19 participants at risk for serious adverse events and 0 participants affected. For other adverse events, it likewise lists 19 at risk and 0 affected. These are the recorded counts for the elastic-assisted treadmill-walking group. They describe what is entered in the registry record; they do not establish that every possible adverse event was systematically captured or that no event could occur outside the recorded reporting period.
The record does not list any serious adverse-event terms. Deaths are not reported in the registry record. It also does not provide details about the adverse-event collection period, how events were solicited or classified, or whether participants completed safety follow-up. Without these details, the counts cannot be interpreted as a complete account of safety monitoring.
General explanation: an adverse-event count is most informative when read alongside the number of participants monitored, the time and method of monitoring, and the definitions used for event categories. A count of 0 affected participants is a registry entry for this study, not proof that an intervention is free of risk. These figures should be interpreted as descriptive registry data rather than as a comparative safety estimate, since the study has no reported control group.
13. What the Result Does, and Does Not, Mean
The registry record documents a study of elastic-assisted treadmill walking among people with spinal cord injury and identifies change in treadmill speed from baseline at 8 weeks as the primary endpoint. It reports enrollment of 19 participants and describes a low-cost rubber-band pulley system intended to assist therapists during gait training. Those details establish the study’s focus and outcome definition.
The record does not report the primary outcome results. It provides no numerical change in treadmill speed, no baseline or follow-up mean, and no measure of uncertainty. As a result, the registry information does not establish whether speed changed, how large any change was, or how consistent participant outcomes were. It also cannot support a judgment about the precision of an estimated change.
The single-group design is important to interpretation. A within-group change can describe outcomes over time for enrolled participants, but it cannot by itself show what would have happened over the same period without the intervention. Since no comparator group is reported, the registry record does not provide a controlled estimate of the intervention’s effect. This is a limitation of the design, not evidence for or against a particular outcome.
Gait kinematics is listed as a secondary outcome, but its numerical findings are not reported in the registry record. The record also does not report analysis methods, missing-data handling, or the analysis population. Consequently, there is not enough information to assess the robustness of any outcome estimate or to determine how many participants contributed measurements at the relevant time points.
The record is informative about the planned clinical focus and the device-based intervention, but it is not a numerical report of efficacy or a comparative safety assessment. The adverse-event entry records 0 affected participants among 19 at risk for both serious and other adverse events, with important monitoring details not reported. These entries should be read descriptively and within the limits of registry reporting.
14. Why This Trial Matters Statistically
Statistically, this study illustrates why the design and completeness of outcome reporting matter alongside the endpoint definition. The registry identifies a continuous primary outcome, its unit, its time frame, and a mean-and-standard-deviation summary. Those details make the intended measurement interpretable, but they do not substitute for a reported estimate, variability measure, or uncertainty interval. Without those results, readers cannot judge the magnitude or precision of observed change.
The single-group design also clarifies the kind of inference available. A before-and-after description can characterize change among participants, but a separate comparator is needed to make a direct between-group contrast. Even a reported within-group change would not by itself distinguish the intervention from other explanations for change over time. The design therefore places limits on causal interpretation independent of the statistical method.
Enrollment of 19 participants is useful context, but it does not disclose how many had complete primary outcome measurements or how missing observations were handled. Reporting the analysis population, outcome availability, and uncertainty around estimates would help readers assess how much information the data contain. The registry record lists 0 analyses, making those aspects of the results unavailable.
The record also demonstrates the importance of distinguishing planning illustrations from an actual study design. The described planning assumptions refer to equal allocation between two arms, while this study is registered as single-group. Such an illustration is hypothetical and cannot be treated as a description of the enrolled study or as observed power. Clear separation of planning assumptions, design, and results is essential to sound interpretation.
15. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
Several trial-specific limitations affect interpretation of the registry record. The study is single-group, with allocation marked not applicable and masking listed as none. No like-for-like control comparison is reported. Therefore, any within-group change, if it were available, could not by itself identify the contribution of the device apart from other possible influences over time.
The registry reports enrollment of 19 participants but does not report how many contributed baseline and 8-week treadmill-speed measurements. It does not describe participant characteristics, eligibility criteria, reasons for missing measurements, or the method used to address missing data. These omissions limit assessment of who the results might represent and how complete the outcome information was.
The primary outcome is defined, but numerical results are not reported. The registry gives no estimate of change, standard deviation, confidence interval, or test result. It lists 0 analyses, so the method used to analyze the continuous outcome is not reported. The registry also does not provide detailed definitions or numerical results for the secondary outcome of gait kinematics.
Intervention delivery is described in broad terms as treadmill training using a low-cost rubber-band pulley system to assist therapists in advancing limbs. Training frequency, session duration, intervention exposure, adherence, and any variation in device use are not reported in the registry record. Safety monitoring details and deaths are also not reported. These limitations concern information absent from the record and should not be mistaken for evidence that any specific issue occurred.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Development of Low Cost Devices to Increase Access to Treadmill Training — NCT02560506.
- Registry record last updated 2026-04-27; status last verified 2026-04.
- Results first posted 2026-04-27.
- 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.
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Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
19. Record Summary
The registry record describes a completed, single-group study of elastic-assisted treadmill walking for people with spinal cord injury. Enrollment was 19, the intervention used a low-cost rubber-band pulley system, and the primary outcome was change in treadmill speed from baseline at 8 weeks, measured in meters per second. Gait kinematics is listed as a secondary outcome.
The record reports no outcome analyses and does not provide numerical results for the primary or secondary outcomes. It also does not report the analysis population, missing-data handling, or detailed intervention schedule. The adverse-event entry lists 0 affected among 19 at risk for serious events and 0 affected among 19 at risk for other events; deaths are not reported in the registry record. The single-group design does not provide a comparator for estimating a controlled treatment effect.