Community-engaged Approaches to Testing in Community and Healthcare Settings for Underserved Populations: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Community-engaged Approaches to Testing in Community and Healthcare Settings for Underserved Populations (NCT04870307), a na na study. The primary outcome is Change in SARS-CoV-2 Testing Rate (Practices).

2. Clinical Question

The question is about implementation and testing processes in participating practices, not the effect of a randomized treatment on individual patients. The broader program also included community-oriented activity, but the stated primary measure is specifically practice-level. That distinction matters: an average practice-level rate describes patterns across practices, and cannot by itself show which patients were tested, why others were not tested, or how individual outcomes changed.

3. Trial Design

NCT04870307 is registered under the title Community-engaged Approaches to Testing in Community and Healthcare Settings for Underserved Populations. The sponsor is the University of Oklahoma. The registry lists the study as completed, with a start date of 2020-09-30 and a primary completion date of 2023-06-30. Its phase and allocation are recorded as NA, masking as none, and model as single group. These entries describe the registry classification; they do not establish details of procedures that are not recorded.

The study summary describes a pragmatic program combining practice-based and community-based approaches. The practice component aimed to support guidelines-based testing and patient education. The community component was designed around mobile testing sites and responsiveness to community testing needs. The registry’s practice-arm description states that a practice-based implementation study was conducted with 35 practices, using baseline data collection, overlapping interim measurements of care quality and process outcomes, and final collection at the end of the intervention. It also states that patients were not direct subjects in this part of the study. The registry enrollment is 323; the relationship between that enrollment entry and the practice description is not explained in the record.

The listed primary outcome is a continuous measure, summarized as a mean with standard deviation, and defined over baseline to 12 months. The registry lists 15 outcome measures and zero analyses. It does not report a randomized allocation, masking, or a concurrent control group. The intervention description and outcome structure therefore support reading the primary question as a change over time in practice-level testing, not as a controlled treatment contrast. A detailed statistical analysis plan, including any adjustments or handling of within-practice dependence, is 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.

Overall Study

Analysis population for the primary outcome, as defined in the registry: The average proportion of patients receiving a SARS-CoV-2 test at the practice-level. Data were collected at the practice level only, no participant or patient level data were collected.

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: Participants are primary care practice members within the 35 participating practices (physicians, physician assistants, nurse practitioners, clinical staff, office managers, etc.)

6. Primary Endpoint

The registry lists the primary outcome as Change in SARS-CoV-2 Testing Rate (Practices), measured over Baseline to 12 months.

The primary endpoint is the change in the proportion of patients eligible for SARS-CoV-2 testing, based on screening, who receive a SARS-CoV-2 test. The measure ranges from zero to one and is summarized as a mean with a standard deviation. Its stated timeframe is baseline to 12 months. The registry defines the population for this measure at the practice level: it is the average proportion of patients receiving a test at the practice level, and no participant- or patient-level data were collected for this outcome.

This kind of process measure can describe whether testing is reaching people who are considered eligible under the screening approach used by the practices. In general, tracking a process outcome over time can help characterize implementation, even when the study does not estimate a randomized treatment effect. The measure is not itself a clinical outcome such as illness or recovery, and the registry does not report details of the screening rules or how eligibility was applied at each measurement.

The endpoint is presented as a change, so interpretation requires both the observed baseline and follow-up information or a reported change estimate, together with its uncertainty. Those results are not reported in the registry record. Without them, the endpoint definition can be explained, but the size, direction, and precision of the change cannot be assessed.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary outcome is a continuous measure: the practice-level proportion of eligible patients who received testing. The registry says that this proportion ranges from zero to one and that the reported parameter is a mean with standard deviation. Those terms describe a planned way to summarize the measure, not an observed result. The numerical mean and standard deviation are not reported in the registry record.

What does a mean and standard deviation describe?

In general, a mean summarizes the central level of a measured quantity across observations. A standard deviation describes how spread out those observations are around the mean. For a practice-level measure, interpretation depends on what counts as an observation and how practices contribute to the summary. The registry identifies the practice as the level of data collection for the primary measure, but the detailed calculation and weighting are not reported in the registry record. For example, the record does not say whether the average gives the same weight to every practice or reflects the number of patients at each practice.

What does change over time mean?

The endpoint compares baseline with the 12-month timeframe. In general, an analysis of change may compare each practice’s follow-up measure with its own baseline measure, or may compare group summaries at the two times. These approaches answer related but not identical questions and can produce different estimates. The registry defines the change outcome but does not report the analysis formula, the exact handling of practices with incomplete measurements, or whether baseline values were used as covariates in a model. Those analytic details are not reported in the registry record.

Repeated measurement within practices also matters. In general, observations from the same practice may be more alike than observations from different practices. Methods that treat dependent measurements as independent can produce uncertainty estimates that are too small. Statistical models can account for clustering or repeated measurements, but which method was used, and whether any such adjustment was made, are not reported in the registry record. Over-dispersion is a general concern when observed variation exceeds what a model assumes; it can affect uncertainty estimates. The record does not report a model or diagnostic assessment that would establish whether over-dispersion was relevant to this analysis.

How should uncertainty be interpreted?

In general, a confidence interval conveys the range of effect values compatible with the observed data and the statistical model. A narrow interval indicates greater precision under that model, while a wide interval indicates more uncertainty. A p-value, when reported, summarizes how compatible the data are with a specified null hypothesis under the model’s assumptions; it is not a measure of effect size or practical importance. Neither a confidence interval nor a p-value for the primary endpoint is reported in the registry record. The change estimate itself is also not reported, so there is no result around which to interpret uncertainty.

Because the study is recorded as single group and has no identified like-for-like control comparison, a before-and-after analysis would not, on its own, distinguish program-related change from changes in the setting or broader circumstances over time. In general, a concurrent comparison can help address some shared time trends, while random allocation can support causal interpretation if the design and conduct justify it. The registry does not report such a randomized comparison for this primary outcome. It also does not report whether an interrupted time-series or another design-based approach was used.

What do the planning assumptions mean?

The registry includes assumptions for a planning illustration based on the observed effect: a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect defined as a stated fraction of the observed effect. For time-to-event illustrations, the stated quantity is the total number of events using the Schoenfeld method; other illustrations are expressed as participants per arm. These are planning conventions, not evidence that the trial used a two-arm design. They do not override the registry’s single-group description, and the assumptions should not be read as the trial’s own design justification.

Planning sample sizes are illustrations of how design choices relate to the ability to detect an effect under assumptions. They are not observed power, and they do not establish that an observed result is reliable. The registry record does not report the study’s own sample-size justification or a protocol-based power calculation. Since no primary effect estimate is reported, the planning illustration cannot be interpreted as a substitute for the missing outcome result.

Finally, the registry lists zero analyses. That entry does not explain whether analyses were performed outside the registry or whether results were submitted elsewhere; such explanations are not reported in the registry record. Statistical conclusions should therefore be limited to the defined endpoint and the registry entries that are actually available.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 15 outcome measures, including the primary testing-rate change and secondary measures concerning vaccination rates and COVID-19 referrals. COVID-19 Referrals appears repeatedly in the listed secondary outcomes. When a study evaluates multiple outcomes or multiple analyses, the chance of at least one apparently unusual result can increase. In general, a prespecified hierarchy or multiplicity adjustment can help govern interpretation across many tests. Whether an adjustment, hierarchy, or other multiplicity strategy was used is not reported in the registry record.

The record lists zero analyses and does not give numerical results for the primary or secondary outcomes. It is therefore not possible to assess whether all planned analyses were reported, whether the listed outcomes were analyzed, or how multiplicity was handled. The protocol and detailed statistical analysis plan are not reported in the registry record. No assumption should be made about which outcomes were primary at the analysis stage beyond the primary outcome designation recorded in the registry.

Missing-data methods are also not reported in the registry record. The entry does not describe the amount or pattern of missing practice measurements, the handling of practices without follow-up data, imputation, or sensitivity analyses. In general, missingness can affect both the estimated change and its precision, particularly if the likelihood of missing data is related to practice characteristics or outcome values. The available record does not establish whether missing data occurred or how any such data were handled.

The primary outcome is practice-level, and the registry explicitly states that no participant- or patient-level data were collected for it. The analysis population, exclusions, and rules for including practices in the primary analysis are not reported in the registry record. Those omissions limit assessment of the population represented by any possible estimate, as well as assessment of whether the analysis followed a prespecified plan.

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.

For the registry group titled Primary Care Practices, 323 people are listed as at risk for serious adverse events and 0 as affected. The corresponding other-adverse-event entries list 323 at risk and 0 affected. The deaths entry is 2. No serious-event terms are listed among the top serious terms.

These entries are counts in the registry record; they are not a complete account of event definitions, timing, severity, or attribution. In particular, the record does not explain the relationship between the listed group, the 323 at-risk entries, the practice-based description, and the practice-level primary outcome. The two deaths should be read as a reported count, not as evidence that the study intervention caused or prevented deaths. Causal attribution and further details about the deaths are not reported in the registry record.

Zero affected in the recorded serious and other adverse-event categories does not mean that risk was absent. It means that no affected participants are recorded in those entries. The registry record does not report additional safety narratives, event definitions, or a method for collecting safety information. These figures should therefore be interpreted narrowly and separately from the testing-rate outcome.

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

The registry record establishes that NCT04870307 was a completed study of community-engaged testing approaches and that its stated primary outcome was a practice-level change in SARS-CoV-2 testing among patients considered eligible. It also describes practice-based implementation activity and a community-based approach involving mobile testing. These details identify the program’s intended setting and the process it sought to measure.

The record does not report the numerical primary outcome, its direction, or its precision. It therefore cannot establish from the posted results whether testing rates changed, how large any change was, or whether it was distinguishable from random variation under a statistical model. It also cannot establish whether any change was caused by the program. A single-group change over time, even when observed, can reflect influences beyond the intervention; the registry does not report a control comparison for the primary question.

The outcome is practice-level rather than patient-level. It can characterize implementation across practices, but it cannot show which individuals received testing or explain why some eligible patients may not have received it. It is not a direct measure of infection, illness, or other clinical outcomes. The outcome definitions for vaccination rates and referrals do not substitute for absent results on those measures.

The listed safety counts are also limited: the registry records 0 affected for serious adverse events, 0 affected for other adverse events, and 2 deaths in the stated group. The record does not provide enough detail to interpret causality or event circumstances. Overall, the registry describes the study’s purpose, design classification, and outcome definitions, but does not provide the outcome analyses needed to quantify what changed or to support a causal conclusion.

13. Why This Trial Matters Statistically

This study is statistically notable because it frames testing as an implementation outcome measured at the practice level. That choice aligns the primary question with how participating practices deliver a process of care, rather than with individual patient outcomes. It also determines the limits of interpretation: a practice-level average is informative about implementation across practices, but does not describe each patient’s experience or explain practice-to-practice differences.

The record describes a pragmatic combination of practice-based and community-based approaches, while the primary endpoint is specifically defined for practices. Keeping the intervention setting and the outcome unit distinct is important when reading a study that includes multiple ways of reaching a community. A measure tied to one component cannot automatically represent the performance or impact of every component in a broader program.

The single-group classification also makes the distinction between observed change and causal effect central. In general, measurements before and after implementation can document temporal patterns, but a comparison strategy is needed to address alternative explanations for those patterns. The registry does not report a randomized control comparison for the primary measure. Nor does it provide an analysis result that would allow the magnitude or uncertainty of any change to be examined.

The record is also a useful reminder that outcome definitions and outcome findings are different kinds of information. The endpoint, timeframe, summary measure, and data level are stated, but the primary result is not reported in the registry record. Without the estimate and its uncertainty, statistical interpretation must stop short of judging the direction or precision of change. This separation between design description, measurement, and reported analysis is especially important for implementation studies, where the meaning of an aggregate process measure depends on its unit and comparison strategy.

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 principal limitation for interpretation is that the registry record does not report the primary outcome result. The magnitude and direction of change, baseline and follow-up values, uncertainty estimates, and test results are not reported. Without these, the primary question cannot be answered from the record.

The study is listed as single group, with allocation recorded as NA. The registry does not identify a like-for-like control comparison for the primary endpoint. Any change over time would therefore need cautious interpretation, since time trends and other changes in practice or community conditions could contribute. The registry does not report an analysis designed to separate those influences.

The primary data are practice-level, and no participant- or patient-level data were collected for that outcome. This limits assessment of individual testing patterns and prevents examination of patient-level variation using the stated primary measure. The record does not explain how practices were weighted in the average, how many practices contributed to the primary result, or how incomplete practice measurements were handled. Although the arm description refers to 35 practices, the registry does not explain how that description relates to the enrollment entry of 323.

The protocol, statistical analysis plan, sample-size justification, multiplicity approach, missing-data methods, analysis population, and model details are not reported in the registry record. The record also lists zero analyses and does not provide results for the other listed outcome measures. These gaps limit evaluation of prespecification, precision, and completeness of reporting. The adverse-event entries give counts but do not provide event-level context or causal attribution. Each limitation concerns information absent from the registry record; none establishes that an unreported procedure or analysis did not occur.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Community-engaged Approaches to Testing in Community and Healthcare Settings for Underserved Populations — NCT04870307.
• Registry record last updated 2025-01-30; status last verified 2025-01.
• Results first posted 2025-01-30.
• 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

NCT04870307 is a completed University of Oklahoma study titled Community-engaged Approaches to Testing in Community and Healthcare Settings for Underserved Populations. It is listed as a single-group study with masking recorded as none and allocation as NA. The registry gives a start date of 2020-09-30, a primary completion date of 2023-06-30, and enrollment of 323.

The primary outcome is the baseline-to-12-month change in the practice-level proportion of patients eligible for SARS-CoV-2 testing who received a test. It is defined as a continuous measure ranging from zero to one, summarized by a mean and standard deviation. The registry does not report its numerical result or uncertainty. It lists 15 outcome measures and zero analyses. The safety entries record 0 affected for serious adverse events, 0 affected for other adverse events, and 2 deaths; further event context is not reported in the registry record.