Management of Distal Radius Fractures in Children Younger Than 11 Years Old.: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Management of Distal Radius Fractures in Children Younger Than 11 Years Old. (NCT02670629), a randomized na study. The primary outcome is Radial Shortening in Degrees - Residual Radiographic Deformities in Terms of the Radial Tilt, Radial Shortening and Radial Variation, Obtained in Both Groups..

2. Clinical Question

The trial addresses a procedural comparison in children with a specific fracture presentation: whether to restore anatomic alignment before casting or leave the fracture in a partially reduced, overriding position. Both groups received a short arm cast. The registry describes follow-up at week 1, 3, 6 and 10, with new X-rays at each consultation; the primary outcome timeframe is 10 weeks.

The question is not limited to radiographs. Secondary outcomes concern pain and residual functional deficits at 10 weeks. These measures give different perspectives on the treatment groups, but they do not change the stated primary focus on radiographic deformity. The registry record does not specify a minimum clinically important difference for the radiographic or secondary outcomes, so statistical contrasts alone cannot establish whether a measured difference would be important to patients or clinicians.

The protocol description notes that anatomic reduction involved anesthesia and sedatives, while the partial-reduction arm received oral medications. The registry says the study was randomized, double-masked and parallel-group. It does not describe who was masked or how masking was maintained. As a result, the record establishes the broad comparison and design labels but does not fully explain how each procedure was implemented or how participants and assessors might have experienced the interventions.

3. Trial Design

This was a randomized, double-masked, parallel-group trial with 58 participants. The registry reports 29 participants in the anatomic closed reduction plus short cast arm and 29 in the partial-reduction overriding-position arm. The trial status is completed. The registry lists a start of 2013-01 and primary completion of 2015-12. The phase is recorded as not applicable.

The treatment contrast was between two management strategies for completely displaced distal radius fractures in children younger than 11 years. In the control arm, clinicians performed closed anatomic reduction under anesthesia using sedatives and applied a short arm cast for 6 weeks. In the other arm, the fracture was left in a partially reduced overriding position without reduction, with a short arm cast for 6 weeks and oral medications. The registry describes follow-up at week 1, 3, 6 and 10, with new X-rays at each consultation.

Random allocation is intended to make treatment groups comparable on average at the start of a trial, including for characteristics that may not be measured. It does not guarantee that groups are identical, especially in a trial of this size. The record identifies the allocation as randomized, but the sequence-generation method, concealment procedures, and any stratification factors are not reported in the registry record.

The double-masked label indicates that the record classified the trial as double-masked, but the identities of the masked parties and practical masking procedures are not reported in the registry record. Because the procedures differ, the record would need to explain how masking was maintained for readers to judge its feasibility. The registry does not describe the sample-size justification, protocol deviations, or analysis population. These omissions limit assessment of design and conduct beyond the basic parallel-group 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.

Before assignment: Patients who had additional fractures or injuries, as well as those who sustained an open distal radius fractures were excluded from the trial before the assignment of groups. Other exclusion criteria included bone diseases, pathological fractures and chronic fractures.

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.

Population: We included 29 patients in both arms. All of the patients included in this trial completed the according follow-up.

6. Primary Endpoint

The registry lists the primary outcome as Radial Shortening in Degrees - Residual Radiographic Deformities in Terms of the Radial Tilt, Radial Shortening and Radial Variation, Obtained in Both Groups., measured over 10 weeks.

The primary outcome is described as residual radiographic deformities at 10 weeks, with radial shortening named in the outcome title and radial tilt, radial shortening and radial variation identified in its description. The registry says the cast was removed after 6 weeks and in-house rehabilitation began when pain had resolved. Simple X-rays were evaluated with the Montoya Classification, which the description says stratifies patients according to time until radiographic consolidation and bone remodeling. The radiographic measures were recorded and compared between groups. The title gives degrees as the unit, while the description also says millimeters were used where needed.

Radiographic measurements provide an objective way to describe alignment and remodeling after a fracture. They can indicate the extent of residual deformity at a stated follow-up point, rather than relying only on symptoms or function. A measure of alignment is relevant to this trial because the two assigned approaches differ in whether anatomic reduction is performed before casting.

The registry does not provide a fuller operational definition for the primary value, including which specific radiographic measure the arm values represent when the outcome title names radial shortening and the description lists several measurements. Nor does it give a clinical threshold for interpreting the magnitude of a difference. The reported arm values are 8.96 for anatomic reduction and 8.998 for partial reduction with overriding position, with standard deviations of 1.2 and 1.34, respectively. The registry labels the summary as a geometric mean, despite also listing standard deviation. These features warrant caution in interpreting the scale and summary statistic as a stand-alone measure of clinical importance.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation depends on the outcome scale, the summary measure, and the comparison that was planned. For this trial, the registry reports arm-level primary values and standard deviations, but it does not report a primary between-group estimate or inferential test. The secondary outcomes include unadjusted comparisons calculated from the posted summary statistics, as well as one registry-listed Chi-squared result for the functional outcome.

What does a confidence interval describe?

General explanation: a confidence interval expresses the uncertainty around an estimated contrast under a specified statistical model. A narrower interval indicates greater precision under that model; a wider interval indicates less precision. It does not show the range of individual participant outcomes, and it does not guarantee that the true effect lies within the interval. For the primary endpoint, no confidence interval is reported in the registry record, so the precision of a primary treatment contrast cannot be assessed from the posted summaries.

For the secondary pain comparison, the unadjusted mean difference is -2.2, with a 95% confidence interval from -2.587 to -1.813 and p < 0.001. For the functional outcome, the unadjusted mean difference is -1.025, with a 95% confidence interval from -1.056 to -0.994 and p < 0.001. These intervals accompany comparisons derived from the posted arm-level summaries. They quantify uncertainty for those unadjusted comparisons under their calculation assumptions; they do not account for possible multiplicity or unreported analysis choices.

How should p-values be read?

General explanation: a p-value measures how incompatible the observed data are with a specified null model, assuming that model and the analysis assumptions are appropriate. It is not the probability that the null hypothesis is true, nor a measure of the size or clinical importance of an effect. The secondary unadjusted comparisons report p < 0.001. The registry separately reports p = 0.003 for a Chi-squared analysis of the functional outcome. Since the registry does not describe that test's input data or its relation to the continuous summary, the two results should not be treated as interchangeable.

A test result can be statistically persuasive while still leaving questions about measurement, clinical importance, bias, and generalizability. The record does not report a prespecified threshold for an important change on either secondary scale. It also does not report a primary p-value, so the secondary p-values cannot be used as substitutes for inference on the primary radiographic endpoint.

What do the standard deviations indicate?

General explanation: a standard deviation describes how dispersed observations are around an average or other summary, depending on the statistical model and scale. It is not the uncertainty of the estimated group mean; that uncertainty also depends on the number of observations and analytic assumptions. The registry lists standard deviations for the primary and secondary arm summaries. For the primary outcome, the record labels the measure a geometric mean but pairs it with standard deviation. A geometric mean is generally used for positive values with a multiplicative interpretation, while standard deviations are often presented on the original or transformed scale. The registry does not explain the scale or calculation, so the pairing should not be interpreted beyond what is stated.

Why can over-dispersion matter?

General explanation: over-dispersion occurs when observed variability is greater than a statistical model expects. If a model understates variability, standard errors may be too small and confidence intervals too narrow, making evidence appear more precise than warranted. This issue is especially relevant when analyzing counts or clustered observations under models that impose a particular variance structure. The registry record does not report a count-based model or an over-dispersion assessment for the outcomes in this trial. It is therefore a general methodological consideration, not a reported trial finding.

What do the planning illustrations mean?

The planning illustrations use observed secondary effects as hypothetical targets, with two-sided significance level 0.05, equal allocation, and a normal approximation. They show participants per arm for 80% and 90% power when targeting 100%, 75% or 50% of the observed effect. Such illustrations are sensitive to the observed effect, which can be unstable, particularly in small trials. They are not the trial's original sample-size justification and are not observed power. The registry record does not report the actual sample-size assumptions or rationale used when the study was designed.

General explanation: power is the probability that a specified statistical procedure will reject a null hypothesis when a particular effect is present, under the assumptions used in planning. Retrospective power calculated from an observed effect does not add useful information beyond the estimate and its uncertainty. The planning figures should therefore be read as hypothetical design illustrations, not as evidence that the trial had a particular probability of detecting its true effect.

10. Multiplicity, Missing Data and Analysis Populations

The registry identifies one primary outcome and two secondary outcomes, but it does not report a full statistical analysis plan. In particular, the order in which outcomes were to be tested, whether a hierarchy was prespecified, and whether multiplicity adjustments were planned are not reported in the registry record. This matters because examining multiple outcomes can increase the chance of a statistically notable result when each is assessed separately.

General explanation: multiplicity can be addressed by methods that control the overall false-positive risk, or by a prespecified testing sequence in which later tests depend on earlier results. Without information on the intended approach, the unadjusted p-values for secondary outcomes should be treated as exploratory rather than as a family of confirmatory tests. The registry's primary endpoint has no posted p-value or confidence interval, so the relationship between primary and secondary testing cannot be reconstructed.

The record reports arm sizes and outcome summaries, but does not describe missing data, exclusions, or analysis populations. The number analyzed for each endpoint, reasons for any missing measurements, and whether an intention-to-treat or per-protocol approach was used are not reported in the registry record. It is also not reported whether all randomized participants completed follow-up at each stated visit. These omissions prevent assessment of possible bias from missing outcomes or departures from randomized assignment.

General explanation: missing outcome data can bias a comparison when the likelihood of missingness is related to treatment assignment or outcome status. The direction and size of any bias depend on the missingness pattern and assumptions used to address it. No imputation approach, sensitivity analysis, or missing-data assumption is reported. The absence of these details does not establish that data were missing; it means the registry record does not allow readers to evaluate the issue.

The record also does not describe whether the endpoint definitions and analysis methods were finalized before outcome data were examined. Nor does it explain the Chi-squared analysis reported for the functional outcome. These missing details limit reproducibility and make it difficult to distinguish prespecified confirmatory analyses from analyses chosen after data collection.

11. 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 2% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: fracture redisplacement after reduction and cast (6.9%).

The registry reports serious adverse events in the anatomic closed reduction plus short cast group among 2 of 29 participants, and none among the 29 participants in the partial-reduction overriding-position group. The listed serious adverse event term is fracture redisplacement after reduction and cast, reported as 6.9%. The record also reports other adverse events among 2 of 29 participants in the anatomic reduction group and none in the partial-reduction group. Death counts are not reported in the registry record.

These figures are counts of participants affected, not a complete account of event timing, severity details, duration, management or relatedness. The registry record does not define the criteria used to classify events as serious, or say whether one participant could contribute more than one event. It does not provide a full listing of non-serious event types. The listed serious term gives context for the reported serious events but should not be assumed to describe every event unless the record says so.

Small group counts can be imprecise: a difference in observed counts does not, by itself, establish a treatment-caused difference in risk. The record does not provide a comparative safety analysis or confidence intervals. These adverse-event figures should therefore be read descriptively and alongside the limitations of reporting, rather than as a complete comparative safety assessment.

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

The registry record documents a randomized comparison of two approaches to managing completely displaced distal radius fractures in children younger than 11 years. It reports group summaries for a radiographic outcome at 10 weeks and secondary summaries for pain and functional deficits. The primary arm values are similar as posted, but the record does not include a formal between-group estimate or uncertainty interval for that endpoint. Consequently, the primary result cannot establish the precision of a treatment contrast.

The secondary results show unadjusted statistical differences in the posted summaries. They do not establish the size of a clinically meaningful benefit, because the registry does not give thresholds for important changes or fully explain the scale interpretation. They also do not establish that the primary radiographic outcome differs in the same way. The registry's separate Chi-squared result for the functional endpoint is not described sufficiently to reconcile it with the continuous summary comparison.

These findings do not prove equivalence between the strategies. A conclusion of equivalence requires a prespecified margin and methods designed to show that uncertainty is contained within that margin. The registry record does not report such a margin or a noninferiority or equivalence framework. Likewise, a lack of a reported primary significance test should not be mistaken for evidence of no difference.

The results also do not establish how the procedures would perform in settings or populations beyond the enrolled children and fracture presentation described. The record does not provide detailed eligibility criteria, baseline characteristics, implementation information, or a clear account of analysis populations. The number of participants is limited, and the available record leaves important statistical and clinical details unspecified.

A careful conclusion is therefore descriptive: the registry posts primary radiographic summaries and secondary outcome comparisons, but the strength of inference about the primary comparison is constrained by the absence of an inferential result and endpoint clarification. No treatment recommendation follows from these registry data alone. Interpretation requires attention to the exact outcome definitions, the uncertainty around contrasts, analysis choices, multiplicity, and completeness of follow-up.

13. Why This Trial Matters Statistically

This trial is statistically interesting because it compares two materially different management strategies while tracking both radiographic and patient-reported outcomes. Random allocation is an important design feature for causal comparison, and the registry records equal group sizes. The primary outcome is closely aligned with the contrast in fracture alignment, but the posted record does not provide a formal estimate of the primary between-group difference.

That gap illustrates why reporting an endpoint and its arm-level summaries is not the same as reporting an interpretable treatment effect. A comparative estimate, uncertainty interval, and clear outcome definition are needed to judge both magnitude and precision. Here, the primary title and description refer to multiple radiographic measures and different units, while the arm summaries are labeled as a geometric mean. The registry does not explain how those elements connect.

The trial also shows why outcomes should be interpreted according to their roles. Secondary measures may offer useful perspectives, but unadjusted tests across multiple endpoints can create a less secure inferential basis than a prespecified primary analysis. A reported small p-value is not a measure of clinical importance and does not solve questions about the analysis plan, missing data, or scale meaning.

Finally, the planning illustrations based on observed secondary effects are not evidence about the trial's original design or its achieved power. Their hypothetical nature is important because effect estimates from a trial can be optimistic or unstable. The registry does not report the original sample-size justification, so the study's planned ability to answer its primary question cannot be assessed from these illustrations.

For biostatistical reading, the central lesson is to distinguish design labels, descriptive summaries, inferential comparisons and clinical interpretation. Each answers a different question. The registry supports a description of the trial and its posted outcomes, but several elements needed for a full evaluation of precision and analysis conduct are not reported.

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 available record. The primary outcome title identifies radial shortening in degrees, while the description lists radial tilt, radial shortening and radial variation and says millimeters were used where needed. The record does not identify which individual measure corresponds to the posted arm values, explain the units for each component, or describe how the geometric mean and standard deviation were calculated. This ambiguity limits interpretation of the primary summaries.

No primary treatment contrast, confidence interval or p-value is reported. Therefore, the primary comparison's uncertainty cannot be assessed from the posted information. The close appearance of the two arm summaries does not demonstrate equivalence, and the record does not report an equivalence margin or a noninferiority analysis.

The registry does not report baseline characteristics, participant flow, analysis populations, or the number with observed data at each follow-up point. It is not possible to determine from the record whether the outcome summaries include all randomized participants or how missing measurements were handled. The allocation method, concealment details, masking procedures and protocol deviations are also not described.

The secondary results include unadjusted comparisons and a separate Chi-squared result for the functional outcome, but the latter's construction is not explained. The registry does not report a prespecified multiplicity approach, clinical importance thresholds, or a complete statistical analysis plan. These omissions limit confidence in treating the secondary findings as confirmatory.

Safety reporting is also incomplete for a full comparison: the record gives affected-participant counts and a serious-event term but does not report event-level detail, relatedness, timing, or a comparative uncertainty analysis. Finally, the registry description offers limited detail on eligibility beyond age and fracture presentation, which restricts assessment of generalizability.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Management of Distal Radius Fractures in Children Younger Than 11 Years Old. — NCT02670629.
• Registry record last updated 2019-12-18; status last verified 2019-12.
• Results first posted 2019-11-14.
• 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 a completed randomized, double-masked, parallel-group trial with enrollment of 58 children younger than 11 years who had completely displaced distal radius fractures. It compared closed anatomic reduction under anesthesia using sedatives plus a short arm cast with partial reduction in an overriding position plus a short arm cast. Both casts were described as lasting 6 weeks, with follow-up at week 1, 3, 6 and 10.

The primary outcome concerns residual radiographic deformity at 10 weeks. The registry posts arm summaries but no inferential comparison for this endpoint. Secondary outcomes concern pain and residual functional deficits at 10 weeks, with unadjusted comparisons calculated from the posted summaries and a separate reported Chi-squared result for the functional outcome. Serious and other adverse-event counts are also posted.

The record does not report the primary analysis plan, sample-size justification, missing-data handling, analysis populations, or a multiplicity strategy. It also leaves ambiguity about the specific radiographic quantity and units represented by the primary arm values. These limitations constrain interpretation of precision, clinical importance and the strength of conclusions from the posted outcomes.