Rehabilitation With or Without Static Progressive Splinting for Wrist Stiffness: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Rehabilitation With or Without Static Progressive Splinting for Wrist Stiffness (NCT01618227), a randomized na study. The primary outcome is Wrist Range of Motion.

2. Clinical Question

3. Trial Design

This was a prospective randomized trial with a parallel-group design and no masking. Participants were assigned to rehabilitation with static progressive splinting or rehabilitation without splinting. The registry lists the study as terminated and records an enrollment of 4. It does not state why the study was terminated, whether termination occurred before or after the planned enrollment was reached, or whether the enrollment figure represents a target, the final number enrolled, or the number contributing to each posted outcome. The registry record does not report a sample-size justification or the intended enrollment target.

The recorded study start is 2008-09, and the primary completion date is 2015-01. These dates identify the registry milestones but do not explain the duration of recruitment, follow-up, or analysis. The phase is listed as NA. Massachusetts General Hospital is identified as the sponsor.

The primary endpoint was wrist range of motion at 2 months. The record describes measurement of wrist flexion and extension using a goniometer, in degrees, with the two movements summed to determine range of motion. The posted group summaries list 2 participants and a mean of 36.5 degrees with a standard deviation of 9.19 for rehabilitation with splinting. For rehabilitation without splinting, the summaries list 2 participants and a mean of 57.5 degrees with a standard deviation of 10.6.

Three secondary outcomes are listed: wrist range of motion, number of physical or occupational therapy visits, and number of additional surgeries. The record also describes planned questions about motion at six months and associations with negative pain thoughts, pain anxiety, and depression. Results for those questions are not reported in the registry record. No analysis is posted for the primary comparison.

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 Wrist Range of Motion, measured over 2 months.

The primary endpoint is wrist range of motion, measured in degrees at 2 months. The registry describes measuring flexion and extension with a goniometer and summing those measurements to determine range of motion. This endpoint represents movement in both directions as a combined measure, rather than reporting flexion and extension separately in the primary result.

Range of motion is relevant to the stated study question because the trial concerns restricted wrist movement after fractures, and its primary hypothesis concerns whether movement differs between rehabilitation with and without static progressive splinting. A goniometer provides a quantified measure of joint movement, allowing the endpoint to be expressed on a continuous scale. In general, a continuous endpoint can be described using a group mean and a measure of spread, such as the standard deviation reported in this record. Those summaries describe the posted observations; they do not, by themselves, establish whether a difference between groups is statistically reliable or attributable to the assigned treatment.

The registry posts group means and standard deviations for the two-month measure but does not post separate flexion and extension results, a confidence interval, a p-value, or an inferential comparison. It also does not report a threshold for a clinically important change in wrist range of motion. The meaning of the group summaries is therefore limited to the measured endpoint and the observations recorded at the stated time point. Further details about measurement procedures, assessor training, and whether measurement was masked are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies a continuous primary outcome, wrist range of motion in degrees, summarized using a mean and standard deviation. It also identifies the study as randomized, parallel-group, and unmasked. These design and measurement details describe the intended comparison, but the registry reports no statistical analysis of the two-month results. The statistical interpretation must therefore remain descriptive.

What does a group mean describe?

In general, the mean is an average of the measurements observed in a group. It condenses multiple measurements into one summary, which can help describe the central level of an outcome. It does not show every participant's value, how values are distributed, or whether the group differs reliably from another group. Here, the posted means are 36.5 degrees with splinting and 57.5 degrees without splinting. Each mean is reported with a standard deviation and a group size of 2.

What does the standard deviation add?

In general, a standard deviation describes the spread of individual measurements around a group mean. A smaller standard deviation indicates that measurements tend to lie closer to the mean, while a larger one indicates greater spread. It is not the same as a confidence interval: it describes variation among observations rather than directly quantifying uncertainty about a population mean. The posted standard deviations are 9.19 and 10.6. Because the group summaries are based on only 2 participants each, these estimates of spread are themselves highly uncertain.

Why is a group comparison more than comparing means?

In general, a formal comparison considers both the estimated difference between groups and the uncertainty in that estimate. The uncertainty depends on factors such as within-group variation and the number of observations. A confidence interval can express a range of values compatible with the data under the chosen analysis and assumptions. A p-value can describe how compatible the data are with a specified null hypothesis under a statistical model. Neither is posted for this comparison. The registry states that values were missing or not estimable for a two-arm comparison of the continuous endpoint, and the analysis count is 0.

What does randomization contribute?

In general, random assignment is intended to make treatment groups comparable in expectation, including with respect to characteristics that are not measured. It does not guarantee balance in a particular small trial, and it does not correct missing outcome data or replace statistical analysis. The record says allocation was randomized but does not report the randomization sequence method, concealment procedures, stratification, or whether assignment was implemented as planned. Those details are not reported in the registry record.

Why does the very small group size matter?

In general, estimates from small groups are more sensitive to individual observations and tend to be less precise than estimates from larger groups. A single participant's measurement can have substantial influence on a group mean and standard deviation when few observations contribute. A small dataset also limits the ability to assess assumptions or characterize unusual values. The posted summaries should therefore be read as descriptions of the recorded observations, not as precise estimates of what would occur in a broader population.

How should planning calculations be understood?

In general, sample-size planning calculations use assumptions about the effect to be detected, the significance level, allocation, and statistical model. The registry describes planning illustrations based on fractions of the observed effect, a two-sided significance level of 0.05, equal allocation, and a normal approximation. Such illustrations are planning scenarios, not observed power and not evidence about the result. They are explicitly not the trial's own design. The registry record does not report a sample-size justification for the study. Specific planning estimates are not reported in the registry record.

In general, power is a property of a planned study under specified assumptions, not a retrospective measure of whether a result is true. A study with few observations can fail to distinguish an effect from random variation even when the point estimates differ. Conversely, a numerical difference alone does not demonstrate an effect. In this trial, no inferential analysis is posted, so neither statistical significance nor the precision of a treatment contrast can be assessed from a reported test or interval.

The method information available therefore supports a limited reading: the endpoint is continuous, the results are presented as means and standard deviations, and the comparison was randomized in a parallel design. The registry does not report the analysis model, handling of missing outcomes, covariate adjustment, test statistic, or inferential results. Any more specific account of how the primary comparison was analyzed would go beyond what is reported in the registry record.

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.

R code and output

arm <- c("Rehabilitation With Static Progressive Splinting", "Rehabilitation Without Splinting")
n   <- c(2, 2)
m   <- c(36.5, 57.5)
sp  <- c(9.19, 10.6)
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  Rehabilitation With Static Progressive Splinting  2  36.500  9.190  -46.069  119.069
CARM  Rehabilitation Without Splinting  2  57.500  10.600  -37.737  152.737

11. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary endpoint of wrist range of motion at 2 months and three secondary outcomes: wrist range of motion, number of physical or occupational therapy visits, and number of additional surgeries. The study description also includes planned questions about range of motion at six months and correlations with negative pain thoughts, pain anxiety, and depression. Considering multiple outcomes or time points can raise a multiplicity issue: in general, the more statistical tests conducted, the greater the chance that at least one result may appear notable by chance. The registry record does not report whether the study used a multiplicity adjustment, a hierarchy of tests, or another strategy for interpreting multiple outcomes.

The analysis count is 0, and the registry states that values were missing or not estimable for a two-arm comparison of the continuous endpoint. No group-comparison analysis is posted. The record does not specify whether this reflects unavailable participant-level data, incomplete outcome reporting, an analysis that could not be performed, or another reason. The reason is not reported in the registry record.

Missing-data handling is also not reported. The registry does not describe how missing measurements were addressed, whether participants were analyzed according to randomized assignment, or which analysis population was used. It does not report participant flow, adherence, withdrawals, or the number with outcome data at each follow-up time beyond the group sizes attached to the posted two-month summaries. Those details are not reported in the registry record.

In general, the way missing observations are handled can affect both the estimated result and its uncertainty, particularly when missingness is related to treatment or outcome. Without an account of missing data and analysis populations, it is not possible to determine how the posted summaries relate to all randomized participants. No assumptions about exclusions, imputation, or intention-to-treat analysis should be made from the available registry information.

12. Safety Results

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

Other (non-serious) adverse events

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

The serious adverse event figures list 2 participants at risk in the rehabilitation-with-splinting group and 2 at risk in the rehabilitation-without-splinting group. The number affected by a serious adverse event is 0 in each group. The figures for other adverse events also list 2 at risk and 0 affected in each group. Death counts are not reported in the registry record. No top serious-event terms are listed.

These figures describe what the registry reports for the small groups represented in the safety record. They should not be read as proof that serious or other adverse events cannot occur. In general, when few participants are represented, an absence of reported events provides limited information about the range or frequency of possible harms. The registry record does not describe the event-collection period, methods for soliciting events, severity definitions beyond the serious-event category, or completeness of safety follow-up.

The figures do not establish a comparative safety profile. No statistical analysis of adverse events is reported, and the record does not provide event narratives or details about causal attribution. The absence of listed serious-event terms means that no such terms appear in the posted record; it does not independently verify that all possible events were captured. These counts should be interpreted as registry-reported observations, not as a prediction of safety for other patients or settings.

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

The registry record addresses a focused question: whether rehabilitation with static progressive splinting was associated with better wrist flexion and extension at 2 months than rehabilitation without splinting. The primary measurement combines flexion and extension into wrist range of motion in degrees. The posted summaries report a mean of 36.5 degrees with splinting and 57.5 degrees without splinting, with standard deviations of 9.19 and 10.6. Each group summary lists 2 participants.

Those numbers describe the recorded measurements, but the registry reports no inferential comparison. There is no p-value or confidence interval, and the record specifically indicates that values were missing or not estimable for a two-arm comparison of this continuous endpoint. The summaries therefore do not establish that the groups differ statistically, nor do they quantify the uncertainty in a treatment contrast. The registry also gives no threshold for interpreting the size of a movement difference as clinically important.

The results do not establish whether splinting caused a change in wrist movement. Randomization is a useful design feature, but the very small posted group summaries and absence of an analysis limit what can be concluded. The record also does not report the reason for study termination or enough detail about participant flow and missing data to explain the relationship between enrollment and the endpoint summaries.

These findings should not be extended to outcomes that are not reported. The six-month range-of-motion question, therapy visits, additional surgeries, and psychological measures are not answered by the two-month primary summaries. The safety figures likewise do not establish a general safety profile. The most defensible interpretation is narrow: the registry records the group-specific descriptive measurements and reports no analysis capable of supporting a comparative conclusion.

14. Why This Trial Matters Statistically

This trial matters statistically because it illustrates the difference between posting descriptive results and providing an interpretable comparison. A randomized design can be valuable, but readers still need an analysis that estimates the treatment contrast and conveys its uncertainty. Here, the registry posts means and standard deviations for the primary continuous endpoint, yet reports no analysis for the two-arm comparison. The observed summaries alone cannot answer the primary comparative question with statistical precision.

The very small group summaries make this distinction especially important. In general, small samples can produce unstable estimates, and individual observations may substantially influence the mean and standard deviation. Reporting a point estimate without an interval or test can invite an overly confident reading of the apparent separation between group summaries. The absence of an inferential result is not evidence that the groups are equivalent; it is an absence of a reported comparison.

The record also highlights why outcome and analysis planning matter. The study description includes a primary endpoint and several secondary questions, but the registry does not report a sample-size justification, a multiplicity strategy, missing-data methods, or analysis populations. Those omissions make it harder to assess how the results were intended to be interpreted and whether the posted summaries represent the intended analysis.

For clinical researchers and biostatisticians, the record is a useful reminder to distinguish study design, observed summaries, and statistical evidence. Randomization describes allocation, while the group means describe outcomes among those represented in the summaries. Neither alone supplies an estimate of uncertainty or a basis for a treatment-effect conclusion. Clear reporting of participant flow, analysis methods, confidence intervals, and outcome availability would be needed to support a more complete evaluation.

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 limitations are specific to the information reported for this trial. The registry lists an enrollment of 4, and each posted primary outcome group summary lists 2 participants. These small numbers sharply limit the precision and stability of descriptive statistics. The reason for the study's terminated status is not reported in the registry record, so the effect of termination on recruitment, follow-up, or analysis cannot be assessed.

The primary comparison has no reported statistical analysis. The registry identifies the endpoint as continuous and states that values were missing or not estimable for a two-arm comparison. No confidence interval, p-value, adjusted estimate, or analysis model is reported. The record does not state why an analysis was unavailable.

Outcome reporting is incomplete for the questions described in the study record. The two-month wrist range-of-motion summary is posted, but results for the six-month comparison, therapy visits, additional surgeries, and psychological associations are not reported in the registry record. Flexion and extension are combined in the primary measure, with no separate results for either motion direction.

Important design and conduct details are also not reported. These include eligibility criteria beyond the condition description, baseline characteristics, allocation procedures, treatment adherence, rehabilitation schedules, measurement assessor procedures, participant flow, missing-data handling, analysis populations, and reasons for withdrawal or termination. The record does not provide a sample-size justification or a stated approach to multiple outcomes. These gaps restrict assessment of comparability, precision, and the scope of the posted findings. They should not be filled by assumptions about how the trial was conducted.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Rehabilitation With or Without Static Progressive Splinting for Wrist Stiffness — NCT01618227.
• Registry record last updated 2017-03-23; status last verified 2017-02.
• Results first posted 2017-03-23.
• 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.

19. Record Summary

NCT01618227 is a randomized, parallel-group, unmasked trial of rehabilitation with or without static progressive splinting for post-traumatic stiff wrists. The registry lists an enrollment of 4, a terminated status, a study start of 2008-09, and a primary completion date of 2015-01.

The primary endpoint was wrist range of motion in degrees at 2 months, defined as the sum of goniometer-measured flexion and extension. The posted mean and standard deviation were 36.5 and 9.19 with splinting, and 57.5 and 10.6 without splinting; each group summary lists 2 participants. The registry reports no analysis for the comparison and indicates that values were missing or not estimable for a two-arm comparison of this continuous endpoint.

Secondary outcomes include wrist range of motion, therapy visits, and additional surgeries. Their results are not reported in the registry record. Serious and other adverse event figures list 0 affected in each group, with 2 at risk per group; deaths are not reported. The posted record supports a descriptive account of the small group summaries, not a precise comparative conclusion.