Effectiveness and Implementation of mPATH-CRC: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effectiveness and Implementation of mPATH-CRC (NCT03843957), a randomized na study. The primary outcome is Percent of Patients Who Complete the mPATH-CRC Program.

2. Clinical Question

3. Trial Design

This completed study is a randomized, parallel-group trial of implementation approaches for mPATH-CRC. The registry record identifies the design as cluster-randomized: clinics, rather than individual patients, were assigned to the high-touch or low-touch strategy. The allocation is randomized and masking is listed as none. The record identifies Wake Forest University Health Sciences as the sponsor and gives enrollment as 77145.

The clinic-level assignment matters to interpretation. Patients treated at the same clinic share a setting and implementation process, so their outcomes may be more alike than outcomes from patients in different clinics. A comparison that treated every patient as independently randomized would not reflect the assigned design. The registry record explicitly cautions that a simple individual-level re-analysis would be misleading. No independent recalculation of the treatment comparison is therefore presented; the sponsor's own analysis would take precedence, but a sponsor effect estimate is not reported in the registry record.

Study groups include eligible clinic patients after implementation under each strategy, all adult clinic patients after implementation, clinic personnel after implementation, and eligible patients before implementation. The arm descriptions identify English- or Spanish-speaking patients for these patient groups. The pre-implementation eligible-patient groups cover the period described as 8 months before implementation; the post-implementation groups are described over 12 months after implementation. These populations and periods are not interchangeable with the primary outcome population, which is defined for the sixth month.

The study is marked completed. Its start date is 2019-10-31 and its primary completion date is 2022-08-25. The record lists the phase as NA. It does not report the number of clinics randomized, clinic-level allocation details, or the specific components distinguishing the high-touch strategy from the low-touch strategy. Those details are not reported in the registry record.

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: This is a pragmatic trial, with data being pulled from the electronic health record, so there is no loss to follow-up. A patient enters the dataset once at the time of their clinic visit; they are not actively followed over time but rather a retrospective data pull was conducted at the end of the study for relevant outcomes. The periods described under the description for "high touch" and "low touch" are at the clinic level, not the patient level.

Overall Study

Analysis population for the primary outcome, as defined in the registry: The analysis population for this outcome is in the sixth month after implementation, so this is a subset of the overall baseline population that includes patients eligible for CRC screening over the full12 months following implementation.

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.

Only the first 6 of 7 groups are shown.

6. Primary Endpoint

The registry lists the primary outcome as Percent of Patients Who Complete the mPATH-CRC Program, measured over Month 6.

The primary outcome is the percent of eligible patients, ages 50–74, who complete the mPATH-CRC program in the sixth month following the implementation date. It is an implementation outcome: it describes whether the program is completed by the defined patient population, rather than measuring a clinical health outcome. The record expresses the outcome as a count of participants and identifies the unit as participants.

A completion measure can help assess whether an implementation approach reaches its intended users and supports use of the program in routine clinical practice. In this study, the focus on a specific month also makes the timing part of the outcome definition. The primary outcome population is described as the sixth-month subset of the broader baseline population, with eligible patients over the full 12 months following implementation included in that broader population. The registry record does not report the observed completion count, the percentage, the denominator used in the posted analysis, or a comparison between strategies. It also does not report the operational criteria used to determine completion beyond the outcome description. These details are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

General statistical context: randomized trials use the assignment process to compare groups while limiting systematic differences at baseline. In a cluster-randomized trial, the unit assigned is a group or setting, such as a clinic, rather than each participant individually. Here the record identifies clinics as the randomized units and names high-touch and low-touch implementation strategies. Analyses should respect that assignment level.

Why does clinic-level assignment matter?

Participants who attend the same clinic may share staff, workflows, resources, and exposure to the implementation strategy. Their outcomes can consequently be correlated. General statistical context: this within-clinic similarity is often described as intracluster correlation. When outcomes are correlated within clusters, treating every participant as an independent randomized observation can make standard errors too small and confidence intervals too narrow. The appropriate analysis needs to reflect both the clinic-level assignment and the outcome structure. The registry record does not report the specific model or variance method used for the primary outcome.

The record itself flags this design issue, stating that a simple individual-level re-analysis would be misleading and that only the sponsor's own analysis is shown. At the same time, it lists 0 analyses and no primary-outcome estimate. Accordingly, no sponsor comparison or independently recalculated comparison is available in the registry record. A method cannot be reconstructed from the design description alone.

What does the primary outcome represent?

The primary outcome is the percent of patients who complete the program in the sixth month following implementation. It is a binary participant-level event summarized as a count or percentage, according to the outcome description. Interpreting a percentage requires a defined numerator—the patients meeting the completion criterion—and denominator—the eligible patients included in that outcome analysis. The record describes the target population and month, but does not report the observed numerator, denominator, or completion criteria in greater detail. The result is therefore not reported in the registry record.

The outcome population also needs to be distinguished from enrollment. Enrollment is 77145, but this is not stated to be the primary analysis denominator. The record defines the primary analysis population by eligibility and the sixth month after implementation, and describes a broader post-implementation population over 12 months. A total enrollment figure cannot substitute for the outcome-specific population.

How should uncertainty be assessed?

General statistical context: an effect estimate, such as a difference in completion between strategies, communicates the magnitude and direction of a comparison. A confidence interval gives a range of values compatible with the observed data and the assumptions of the statistical method. A p-value summarizes how unusual the data would be under a specified null model; it does not quantify the size or practical importance of an effect. These quantities must be interpreted alongside the design, outcome definition, and analysis population.

No effect estimate, confidence interval, or p-value for the primary outcome is reported in the registry record. Consequently, statistical significance and precision cannot be assessed from this record. It would also be inappropriate to infer that a non-significant finding occurred, because there is no reported test result. For cluster-randomized data, valid uncertainty estimates need to account for clustering; a participant-level calculation that ignores the randomized clinics would not do so.

What can planning illustrations tell a reader?

The sample-size material is described as a planning illustration computed from the observed effect, not as the trial's original design. The stated assumptions are a two-sided significance level of 0.05, equal allocation between strategies, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. Such illustrations address how many participants per arm might be needed under those assumptions. They are not observed trial outcomes, and they are not observed power.

General statistical context: a planning calculation depends on the assumed effect, variability, allocation, significance threshold, and analysis method. For a cluster-randomized design, planning also needs to reflect clustering and the number and size of clusters. The registry record does not report the original sample-size justification or enough information to establish whether a planning illustration accounts for the trial's cluster structure. It should therefore not be read as evidence that the trial was adequately or inadequately powered. The actual planning values are not stated in the record summary available for this interpretation.

The record does not identify an interim-analysis plan, covariate adjustment strategy, handling of repeated or missing observations, or the detailed statistical model. These features may affect estimates and uncertainty, but they are not reported in the registry record. Without those details or posted outcome results, the defensible statistical reading is limited to the stated design, outcome definition, and explicit caution about individual-level re-analysis.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Clinic Patients Eligible for CRC Screening on 'Hig", "Clinic Patients Eligible for CRC Screening on 'Low")
n      <- c(558, 397)
events <- c(5, 4)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Clinic Patients Eligible for CRC Screening on 'Hig  558  5  0.9  0.3  2.1  0.4  2.1  0.4  2.1
ARM  Clinic Patients Eligible for CRC Screening on 'Low  397  4  1.0  0.3  2.6  0.4  2.6  0.4  2.6

11. Multiplicity, Missing Data and Analysis Populations

The registry record names 18 outcome measures and lists several secondary implementation outcomes, including reach by socioeconomic strata, adoption, fidelity, maintenance, and colorectal cancer screening tests ordered. It does not report how the analyses were prioritized beyond naming the primary outcome, nor does it describe a multiplicity adjustment or a strategy for interpreting multiple secondary comparisons. Those plans are not reported in the registry record.

General statistical context: when many outcomes or comparisons are tested, the chance of at least one apparently unusual result can increase. A prespecified primary outcome can help focus interpretation, while adjustment methods or a hierarchy of tests can address multiplicity. Without a stated analysis plan and results, it is not possible to determine whether multiplicity was addressed or how secondary findings were intended to support conclusions. No secondary outcome results are reported in the registry record.

The record describes the primary analysis population as eligible patients in the sixth month after implementation and separately describes wider post-implementation populations and pre-implementation groups. It does not state how missing outcome information was handled, whether all eligible patients had outcome status available, or whether any participants were excluded from the analysis. It also does not describe an imputation method or sensitivity analyses for missing data. These details are not reported in the registry record.

General statistical context: missingness can affect an estimate when the chance that an outcome is unobserved is related to patient characteristics or outcome status. The direction and size of any such effect depend on the underlying data and assumptions, so they cannot be inferred from the registry description. With no reported outcome counts or missing-data methods, the extent of missingness and its influence on the comparison cannot be assessed.

12. 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 adverse-event entries list zero serious events, zero other events, and zero deaths in each reported group. For eligible patients after implementation, the high-touch group lists 7933 at risk and the low-touch group lists 5159 at risk. For all adult patients after implementation, the corresponding at-risk counts are 43775 and 23359. For clinic personnel after implementation, they are 282 and 232. The pre-implementation eligible-patient groups list 5526 at risk under high touch and 3971 under low touch. Each of these groups has zero serious events, zero other events, and zero deaths in the registry record.

These entries describe what was reported for the listed groups; they do not show that no event could have occurred outside the record's reporting scope. The groups include different populations and periods, so their at-risk counts should not be combined or treated as equivalent exposure groups. The record does not describe event definitions, ascertainment procedures, or the basis for including these implementation populations in adverse-event reporting. Those details are not reported in the registry record. The absence of listed events is not, by itself, a comparative safety analysis or evidence of a treatment effect.

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

The study addresses an implementation question: how mPATH-CRC can be put into clinical practice, including whether high-touch or low-touch implementation is associated with program completion among eligible patients. Its cluster-randomized design is relevant because clinics, not individual patients, were assigned to strategies. The record also identifies a broader set of implementation outcomes, such as reach, adoption, fidelity, and maintenance.

What the posted record does establish is the planned focus of the primary outcome, the population and timing described for that outcome, the randomized parallel-group design, and the listed study groups. It reports enrollment of 77145 and marks the study completed. It also reports zero serious events, zero other events, and zero deaths across the adverse-event groups listed. Those details describe the registry entries; they do not supply the comparative results needed to judge completion or implementation performance.

The record does not report the primary outcome value, a difference between high-touch and low-touch clinics, an uncertainty interval, or a statistical test. It therefore cannot show whether either strategy had a higher completion percentage, how large any difference might be, or how precise an estimate would be. Nor does the lack of a reported estimate imply that the strategies had identical outcomes.

General statistical context: an implementation result is most informative when it is read alongside its population, outcome definition, time period, analysis method, and uncertainty. For a cluster-randomized study, the analysis must also account for clinic-level assignment. Those considerations are especially important when assessing whether an observed difference is credible and how broadly it can be applied. In this registry record, the necessary comparative results and several analysis details are not reported. The appropriate conclusion is therefore about the limits of the record, not about whether mPATH-CRC or an implementation strategy succeeds or fails.

14. Why This Trial Matters Statistically

This trial is statistically notable because the implementation strategy is assigned at the clinic level while outcomes are described for patients and clinic personnel. That structure illustrates why the unit of randomization and the unit of outcome measurement are not always the same. A valid comparison must preserve the clinic-level assignment in its analysis rather than treating all participants as individually randomized.

The study also distinguishes an outcome tied to a specific implementation month from broader patient populations observed over a longer post-implementation period. That distinction is important: an overall enrollment figure does not identify the analysis population for a time-specific outcome. Interpretation depends on matching the outcome numerator and denominator to the population and period set out in the outcome definition.

Implementation research often considers more than a single patient-level endpoint. This registry record lists reach, adoption, fidelity, maintenance, and screening tests ordered alongside the primary completion outcome. These domains capture different aspects of delivering and sustaining a program. Their presence makes a clear outcome hierarchy and a transparent approach to multiple analyses especially useful, although those plans are not reported in the registry record.

Finally, the record demonstrates the difference between a study's completion status and the availability of analyzable results. The study is marked completed, but no analyses are listed and the primary result is not reported. Without estimates and uncertainty, readers cannot assess the direction, magnitude, or precision of the comparison. Statistical transparency requires the reported outcome data and the design-appropriate analysis, not just a trial description or total enrollment.

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.

The central limitation for statistical interpretation is that the registry record does not report the primary outcome result or any analysis. There is no completion percentage, comparison estimate, confidence interval, or test result to evaluate. The record lists 0 analyses, so the comparative effect and its precision cannot be assessed from the posted information.

The primary outcome description identifies eligible patients aged 50–74 and the sixth month after implementation, but the observed numerator, denominator, and detailed completion criteria are not reported. Although total enrollment is 77145, the record does not establish that this number corresponds to the primary outcome population. It also does not report the number of randomized clinics or the clinic-level allocation details, which limits assessment of the design and its statistical precision.

Several methodological details are absent, including the statistical model, treatment of clustering in the sponsor analysis, covariate adjustment, missing-data handling, and multiplicity plan. Interim analyses and the original sample-size justification are also not reported in the registry record. These omissions prevent a full assessment of whether the analysis matched the design and how robust the results would be to alternative assumptions.

The descriptions of high-touch and low-touch strategies do not specify their implementation components, and the record does not explain how program completion was ascertained. The listed adverse-event groups have zero reported events, but event definitions and ascertainment procedures are not described. These limitations concern the information available in the registry record and do not establish that the study itself lacked these procedures or analyses.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Effectiveness and Implementation of mPATH-CRC — NCT03843957.
• Registry record last updated 2024-01-31; status last verified 2024-01.
• Results first posted 2024-01-31.
• 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

NCT03843957, titled Effectiveness and Implementation of mPATH-CRC, is a completed randomized, parallel-group, cluster-randomized study sponsored by Wake Forest University Health Sciences. Enrollment is listed as 77145. The study compares high-touch and low-touch implementation strategies for mPATH-CRC and also lists mPATH-Checkin among its interventions. Masking is listed as none.

The primary outcome is the percent of eligible patients aged 50–74 who complete mPATH-CRC in the sixth month following implementation. The record lists 18 outcome measures and 0 analyses. It does not report a primary outcome estimate or comparative statistical result. The adverse-event groups each list zero serious events, zero other events, and zero deaths. The registry record describes the design and intended outcomes, but does not provide the results needed to judge the relative performance or precision of the implementation strategies.