Rotator Cuff Pathway: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Rotator Cuff Pathway (NCT03717753), a non-randomized na study. The primary outcome is Primary Outcome - Worst NRS With Movement.

2. Clinical Question

The study focuses on pain after rotator cuff repair, a setting in which the record says patients may still experience moderate to severe postoperative pain despite regional anesthesia and opioids. Its stated aim is to assess whether a comprehensive pathway is associated with lower worst pain with movement than the practice used before the pathway began.

The design matters to the question. Patients were assigned to groups by when they were studied relative to pathway initiation, rather than by randomization. Consequently, the observed contrast, if reported, would combine any pathway association with possible differences over time between the before and after groups. The record does not provide outcome results with which to estimate that association.

3. Trial Design

This is a completed, non-randomized before-and-after study, with a sequential model and single masking recorded. The study title identifies arthroscopic rotator cuff repair and pain during the period after block placement. The registry lists enrollment as 140. Its description planned 70 patients before pathway initiation and 70 after initiation. These are stated enrollment figures and plans; the registry record does not provide a flow of participants through treatment, follow-up, or analysis.

The before group represents the practice preceding pathway introduction; the after group represents care following its introduction. The summary describes the comparison as the pathway versus current standard practice and says that both groups receive identical postoperative follow-up. The record does not describe how the pathway was implemented, the exact regional technique or analgesic components, or whether practice changed in other ways during the study period.

Because allocation is based on study period rather than random assignment, measured and unmeasured differences between the groups could influence the comparison. Changes in staff, patient mix, procedures, or other care over time are general possibilities in before-and-after research; whether any occurred in this study is not reported in the registry record. The meaning of “single” masking, including whose assessments or treatment knowledge were masked, is also not reported.

The registry gives the study start as 2018-09-07, primary completion as 2020-01-26, and status as completed. These dates describe the registered study timeline, not the timing or availability of an analysis. Although the record lists five outcome measures, it lists zero analyses and does not report primary-outcome estimates. The registry record also does not report the protocol’s rationale for the planned enrollment or whether any changes were made during the study.

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 Primary Outcome - Worst NRS With Movement, measured over 0-48 hours after block placement.

The primary endpoint is worst NRS pain with movement, recorded as a mean with standard deviation during 0-48 hours after block placement. The record describes the score range as 0 to 10 and states that a lower score is a better outcome. The measure is intended to capture the worst movement-related pain during the specified postoperative period, rather than pain at rest or an average across all pain assessments.

Movement-related pain is relevant to the study’s stated aim because the pathway is intended to address postoperative pain after rotator cuff repair. A standardized numeric rating scale can turn a patient’s reported pain into a continuous measure that can be summarized across a group. Reporting a mean describes the group’s average score, while the standard deviation describes the spread of individual scores around that average. These statistics answer different questions: the mean concerns typical level, and the standard deviation concerns variability.

The registry record does not report the group means, standard deviations, difference between groups, confidence interval, or test result. Therefore, the endpoint definition clarifies what the study intended to measure but does not establish what scores were observed or how precisely any group contrast was estimated. The record does not provide additional details about the timing or frequency of movement assessments within 0-48 hours.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The study uses a continuous primary outcome: the mean of a numeric pain score. Its primary measure is worst NRS pain with movement during 0-48 hours after block placement, with a stated scale range of 0 to 10. The registry specifies standard deviation as the dispersion measure. A mean gives a summary of average score, while a standard deviation describes how much individual scores vary around that mean. Neither statistic is reported for the study groups in the registry record.

What does a group comparison estimate?

In general, a comparison of group means describes how the average outcome differs between groups. A confidence interval, when reported, gives a range of values compatible with the data and the analysis assumptions, and communicates the uncertainty around an estimated contrast. It is not reported in the registry record, so the precision of the primary comparison cannot be assessed. A p-value, if available, would address compatibility with a specified statistical null model; it would not by itself describe the size or practical importance of a difference. No p-value is reported.

What does the sequential design imply?

The groups are defined by whether patients were studied before or after the pathway began. This is not randomized allocation. In general, randomization helps balance measured and unmeasured characteristics in expectation, whereas a before-and-after design can leave group differences entangled with changes over time. For example, a shift in patient mix or other care could coincide with pathway introduction. These are general methodological concerns, not claims that such changes occurred in this study. The registry record does not report an adjusted analysis or details that would show how possible time-related differences were handled.

Why can variability matter?

In general, greater variation among individual measurements makes a group mean less precise when other aspects of a study are held constant. The standard deviation is useful for describing that variation, but the record does not give group standard deviations. Pain scores may also vary by person and assessment time; the registry does not explain how observations across 0-48 hours were collected or reduced to the stated worst score.

What does over-dispersion mean in general?

Over-dispersion means that observed variability is greater than a statistical model expects. It matters when a model assumes a particular level of variability, because standard errors and confidence intervals can then be too small if that extra variation is ignored. This concept is general and does not imply over-dispersion in this study. The primary endpoint is described as a continuous mean with standard deviation, and the record does not report a model, diagnostic assessment, or finding about over-dispersion.

How should planning calculations be read?

The registry’s sample-size assumptions describe a planning illustration based on an observed effect, not the trial’s own design. The stated assumptions are a two-sided significance level of 0.05, equal allocation between the groups, and a normal approximation; the effect to detect is a stated fraction of the observed effect. Such calculations are planning illustrations, not observed power and not evidence that a target effect was detected. The registry record does not report an observed primary effect or the planning outputs needed to evaluate the illustration. The enrollment plan itself is stated as 70 patients before and 70 after pathway initiation; the record does not report a sample-size justification.

More broadly, a complete statistical interpretation would need the observed outcome summaries, a clearly defined contrast, its uncertainty, and information about analysis choices and missing data. Those details are not reported in the registry record. Without them, statistical methods can be explained conceptually, but an estimate of pathway association cannot be reconstructed or evaluated.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists five outcome measures and names secondary outcomes concerning total opioid use, satisfaction with pain management, pain at rest, and block duration. It identifies worst NRS pain with movement as the primary outcome. The record does not report results for these outcomes, an analysis plan specifying how they were tested, or any adjustment for multiple comparisons. Multiplicity is a general concern when several outcomes or tests are examined: the chance of at least one apparently notable result can increase if many inferences are made without an appropriate plan. Whether that issue arose in the analyses for this study is not reported in the registry record.

Missing-data handling is also not reported in the registry record. The record does not say how incomplete pain assessments or missing secondary outcomes were treated, whether any imputation was used, or whether sensitivity analyses were conducted. These details matter because results may depend on which participants have usable measurements and on assumptions about why data are missing.

The analysis populations are not described. The registry record does not report how many participants were included in each endpoint analysis, whether all enrolled participants were analyzed, or whether exclusions occurred. The stated enrollment and planned group sizes do not establish the number contributing outcome data.

The record lists zero analyses. That absence means analysis details and estimates are not available in the registry record; it should not be taken as proof that no analyses were performed. The statistical plan, including any interim analyses or prespecified handling of multiplicity and missingness, is not reported in the registry record.

11. Safety Results

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

Deaths

Other (non-serious) adverse events

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

The registry’s adverse-event entries list 70 people at risk in the Before Group and 70 in the After Group. For both groups, the serious-event count is 0, the other-event count is 0, and deaths are recorded as 0. These are the figures recorded for the adverse-event categories; they do not provide detailed descriptions of how events were solicited, assessed, or attributed.

A zero recorded count should be read narrowly: the registry record reports no events in that category for the listed group. It does not, by itself, establish that no events occurred outside the reporting process or that every participant had complete safety follow-up. The record does not report the definitions used for event severity, the surveillance methods, or whether events were considered related to the pathway.

Safety counts also do not answer the primary pain question. They concern adverse-event reporting, while the primary endpoint is a pain score during 0-48 hours after block placement. The registry record does not report outcome estimates for pain or the secondary outcomes, so these safety figures cannot be used to infer the pathway’s effect on those measures.

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

The registry record describes a study intended to assess whether a comprehensive pathway was associated with lower worst pain with movement after arthroscopic rotator cuff repair. It identifies the before and after groups, the primary endpoint, its scale, and the time period of interest. It also reports a completed status and enrollment of 140. These registry entries describe the study’s design and registration; they are not findings about the pathway’s association with pain.

The record does not report the primary outcome values or a between-group estimate. As a result, it does not show whether the after group had higher, lower, or similar mean pain scores, and it does not quantify uncertainty. No conclusion about the size or precision of an association can be drawn from the endpoint description alone. The listed adverse-event counts do not substitute for primary outcome results.

Even if a group difference were available, the non-randomized before-and-after design would require cautious interpretation. A difference could reflect the pathway, other changes across the study periods, or a combination. Whether participant characteristics or care practices differed, and whether analyses adjusted for any such factors, is not reported in the registry record. This is a general limitation of the design, not evidence that a particular source of bias occurred.

The record does not report information about missing outcome data, analysis populations, or the statistical methods used for an outcome comparison. It also does not report a sample-size justification. Therefore, the planned group sizes should not be treated as proof that the study could detect a particular effect, and planning calculations should not be interpreted as observed power.

The appropriate reading is descriptive: the registry states what the investigators intended to compare, but does not report the result of that comparison. The record cannot establish the direction, magnitude, precision, or causal interpretation of a primary-outcome association.

13. Why This Trial Matters Statistically

This study addresses a practical statistical question: how should pain outcomes be compared when a care pathway is introduced in routine clinical practice and patients are observed in periods before and after implementation? Such designs can describe changes associated with implementation, but the time-based allocation means that the pathway’s association may be difficult to separate from other temporal changes. Recognizing that distinction is important when interpreting a clinical comparison.

The primary endpoint is also clearly tied to the clinical question: worst pain with movement during 0-48 hours after block placement, recorded as a mean on a 0 to 10 scale. Distinguishing movement pain from pain at rest, and worst pain from an average across assessments, helps define what the endpoint represents. The listed secondary outcomes broaden the topics of interest, including opioid use, satisfaction, pain at rest, and block duration.

Statistically, a useful interpretation would require more than an outcome label or a group size. Readers need the group summaries and a between-group estimate, together with a measure of precision and information about missing data and analysis choices. The registry record does not report these results or methods, so it illustrates why design descriptions and outcome definitions cannot replace posted estimates.

The record also makes the distinction between a planning illustration and a trial’s own design relevant. A calculation based on an observed effect is a planning exercise, not observed power and not evidence of a treatment effect. For this study, the underlying observed effect is not reported in the registry record, so the planning assumptions do not supply a result to interpret.

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 most important limitation for interpreting the registry entry is the absence of primary outcome results. The record does not report group means or standard deviations for worst NRS pain with movement, an estimated contrast, or its precision. It also lists zero analyses. Consequently, the intended comparison cannot be evaluated from the registry record.

The sequential before-and-after design is another trial-specific constraint. Patients entered groups based on study period, not random assignment, so differences between periods could be associated with the observed outcome. The record does not report whether patient characteristics, clinical practice, or other contextual factors changed, nor does it describe adjustment for potential confounding. This does not prove that group differences existed; it limits what can be concluded if a contrast is later reported.

The registry record gives limited information about the intervention. It describes a comprehensive pathway that includes a well-defined regional technique and multimodal analgesia, but does not specify the actual components or implementation. The comparator is described as current standard practice, without further detail. The meaning of single masking is not defined, so it is unclear who was masked or what assessments might have been protected from knowledge of group.

Outcome collection and analysis details are also absent. The record does not state the number or timing of pain assessments within 0-48 hours, how the worst score was determined, or how missing measurements were handled. It does not report analyzed populations, adjustment methods, or multiplicity procedures. These gaps limit assessment of measurement, precision, and potential bias.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Rotator Cuff Pathway — NCT03717753.
• Registry record last updated 2024-12-27; status last verified 2024-12.
• Results first posted 2023-01-11.
• 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

NCT03717753 is a completed, non-randomized, sequential before-and-after study titled “Rotator Cuff Pathway.” It concerns a comprehensive pathway introduced for patients undergoing arthroscopic rotator cuff repair. The registry lists enrollment as 140 and describes plans for 70 patients before and 70 after initiation. The study start is recorded as 2018-09-07, with primary completion on 2020-01-26.

The primary endpoint is mean worst NRS pain with movement during 0-48 hours after block placement, on a scale from 0 to 10, with lower scores described as better. Secondary outcomes listed are total opioid use, satisfaction with pain management, pain at rest, and block duration. The adverse-event entries show 0 serious events, 0 other events, and 0 deaths in each group.

The registry record lists zero analyses and does not report primary-outcome results, estimates, or analysis details. The design and endpoint can therefore be described, but the association between pathway introduction and the primary pain outcome cannot be quantified from this record.