Improving Communication for Primary Care Patients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Improving Communication for Primary Care Patients (NCT04819191), a randomized na study. The primary outcome is Number of Patients 65 and Older With New Documentation of Any Advance Directive in the Electronic Health Record (EHR).

2. Clinical Question

3. Trial Design

This is a randomized, parallel-group pragmatic trial comparing SHARING Choices with usual care. The registry lists no masking. It identifies the intervention as behavioral and records the study as completed. The sponsor is Johns Hopkins University, and the trial identifier is NCT04819191. Enrollment is listed as 64915.

The registry start date is 2021-03-01, and the primary completion date is 2023-11-20. Those dates describe the record's study milestones; they do not establish the exact observation period for each participant. For the primary outcome, the record defines an individual observation period of 12 months beginning with each candidate patient's initial visit after trial inception. Comparable observation periods are to be constructed for intervention and control candidates.

The intervention is a package: a clinic letter introducing advance care planning, facilitator access, patient-family agenda-setting, optional assistance with portal registration, and education and resources about Alzheimer's Disease and Related Dementias for clinic staff. The comparator is labeled usual care. More detail on usual care, the randomization procedure, allocation concealment, and the assignment ratio is not reported in the registry record.

The record lists the phase as NA. It does not report the number of sites, how participants or clinics were recruited, whether assignment occurred at the patient or site level, or whether the analysis accounted for clustering. Those design details matter for interpreting precision and generalizability, but cannot be inferred from the broad description of the trial as pragmatic. Although enrollment is recorded, the registry does not report how many participants contributed data to the primary outcome.

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: New Advance Directive or MO(L)ST Among Patients Without Documentation At Baseline - Excluding patients who did have an existing Advance Directive or MO(L)ST at the time of entry to the study cohort. Participants who had new uploads of Advance Directives or MO(L)ST after baseline are reported.

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 Number of Patients 65 and Older With New Documentation of Any Advance Directive in the Electronic Health Record (EHR), measured over 1 year.

The primary endpoint is the number of patients 65 and older with new documentation of any advance directive in the electronic health record. The registry defines eligible baseline status by excluding patients who already had an advance directive or MO(L)ST at entry to the study cohort. It counts new uploads after baseline. The specified documentation types include a durable power of attorney, a living will, a Maryland Medical Order for Life Sustaining Treatment, and a District of Columbia Medical Order for Sustaining Treatment.

The outcome is assessed using information recorded in each care delivery system's electronic medical record 12 months after study entry. The initial visit date after trial inception begins the observation period, with comparable periods specified for the intervention and control groups. The outcome unit is participants, and its stated timeframe is 1 year.

As a general measurement rationale, an electronic record can capture whether specified documentation was added during a defined follow-up period. This makes documentation a concrete outcome for a communication and planning initiative. It is not a direct measure of the content or quality of a discussion, whether a patient's preferences changed, whether family perspectives were aligned, or whether care later followed a documented preference. The registry results do not report the observed endpoint counts or a comparison between groups.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a randomized, parallel-group trial with no masking. Random assignment is intended, in general, to make groups comparable on average at the time of assignment, including on characteristics that were not measured. A parallel design follows groups assigned to different conditions rather than assigning the same participant to each condition. These design labels do not by themselves establish how assignment was carried out or how the data were analyzed. Allocation concealment and the unit of randomization are not reported in the registry record.

What does the endpoint count?

The primary outcome is a count of participants who meet a binary event definition: new documentation of an advance directive in the electronic health record during the specified follow-up. The record lists the endpoint unit as participants and identifies qualifying document types. At an individual level, a patient either meets the definition or does not; at a group level, those outcomes can be summarized as counts and, when denominators are known, as proportions. The registry does not report the observed counts or denominators, so no such proportion or group contrast can be stated.

In general, a binary outcome can be compared using measures such as a difference in proportions or a ratio of proportions. A confidence interval would communicate the range of effect sizes compatible with the data under the analysis assumptions. A p-value addresses how compatible the data are with a specified null hypothesis under a statistical model; it is not an estimate of the size or practical importance of an effect. These are general explanations, not reported analyses from this trial. The registry gives no effect estimate, confidence interval, or p-value for the primary endpoint.

What does the planning description mean?

The registry's sample-size planning description refers to an illustration computed from an observed effect, using a two-sided significance level of 0.05, equal allocation, and a normal approximation. It also describes planning to detect stated fractions of that observed effect. Such calculations are hypothetical planning illustrations, not observed trial outcomes and not observed power. No planning illustration values or observed effect are reported in the registry record. The record does not report the trial's own sample-size justification or whether these assumptions were used to design the trial.

In general, an illustration based on a fraction of an observed effect asks how a future study might be planned to detect a smaller or otherwise specified portion of an effect estimate. Its usefulness depends on having an effect estimate and on assumptions about the design and analysis. It cannot establish that the original study was adequately powered, nor can it replace an analysis of the trial data. Since no observed primary effect is reported in the registry record, the planning illustration cannot be interpreted as evidence about this comparison.

Why are uncertainty and model details important?

Randomized assignment supports a comparison, but the estimated effect and its uncertainty depend on which observations are included, how missing records are handled, and whether the statistical model reflects the design. If participants were assigned by clinic or another cluster, outcomes within a cluster could be correlated; a valid analysis would generally need to account for that dependence. This is a general statistical consideration, not a claim that the trial used cluster randomization. The unit of assignment and any adjustment for clustering are not reported in the registry record.

For an outcome based on electronic records, completeness and comparability of record capture are also relevant. In general, incomplete outcome data can affect both the estimate and its precision, especially if the missingness differs between groups or relates to the outcome. The registry does not report missing-data methods, the amount of missing endpoint information, or sensitivity analyses. It also does not report whether the primary analysis was adjusted, which covariates were used, or which analysis population was specified.

The record lists no analysis entries. A statistical analysis plan, interim analyses, multiplicity adjustment, and details of any model used are not reported in the registry record. Therefore, methods such as covariate adjustment, robust standard errors, imputation, or subgroup analysis cannot be attributed to this trial. They can be relevant in general, but should not be mistaken for analyses documented. The posted record supplies enough design and endpoint information to understand the intended question, but not enough statistical output to evaluate the estimated effect or its precision.

10. Multiplicity, Missing Data and Analysis Populations

The registry indicates that the primary outcome has several categories or time points and is not reduced to one comparison. It does not provide a single group contrast to evaluate, nor does it report how multiple categories or time points were handled in the analysis. A multiplicity strategy, such as a prespecified primary contrast or adjustment across multiple tests, is not reported in the registry record. Consequently, the record does not establish which comparison would be treated as primary for inference or how the chance of false-positive findings across analyses was addressed.

Missing-data methods are not reported in the registry record. The record gives no group-specific endpoint denominators, extent of unavailable electronic records, follow-up completeness, or description of how missing endpoint status was treated. It is therefore not possible to assess whether missingness was balanced across groups or whether it could affect the comparison.

The endpoint definition excludes patients who had an advance directive or MO(L)ST at baseline. This is a stated eligibility feature of the endpoint population, not a missing-data rule. How other analysis populations were defined is not reported in the registry record. The record does not say whether analyses followed randomized assignment, used an as-treated population, or applied another inclusion rule. It also does not report a statistical analysis plan, interim analyses, or sensitivity analyses. These omissions limit assessment of the analysis choices, independently of the fact that the primary outcome results are not posted.

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

The registry record establishes what SHARING Choices was intended to offer and how new advance-directive documentation was to be counted. It does not report the primary outcome result. Accordingly, the record does not establish whether the groups differed, the size or direction of any difference, or how precisely a difference was estimated. A completed study status and an enrollment entry do not answer those statistical questions.

Even if an effect estimate were available, the endpoint would describe new documentation in an electronic health record, rather than every component of advance care planning. In general, a document in a record is not equivalent to evidence that a discussion occurred, that preferences were understood or aligned, or that subsequent care reflected those preferences. Conversely, a discussion or decision that was not entered into the record would not necessarily be captured by this endpoint. The registry does not report how often such situations occurred.

The intervention is a package of communication, facilitation, agenda-setting, portal support, and staff education. The record does not describe a component-specific comparison, so any future overall contrast would concern the package as a whole rather than identify the contribution of an individual element. The comparator is labeled usual care, but its content is not detailed in the registry record.

The record lists zero counts in its displayed serious-event, other-event, and death fields for each group. Those entries do not replace a complete assessment of safety or establish what was collected, monitored, or reported outside those fields. No medical recommendation follows from these registry entries. The appropriate statistical conclusion is limited: the question and planned measurement are described, but the primary outcome findings and their uncertainty are not reported.

12. Why This Trial Matters Statistically

This trial is statistically notable for studying a communication and planning intervention using a concrete electronic-record endpoint in a pragmatic primary care setting. Randomized comparison can, in general, help distinguish an intervention contrast from differences that arise because groups began with different characteristics. The registry describes the broad design and the outcome definition, making the intended comparison understandable even though its results are absent.

The endpoint also illustrates a measurement issue common to pragmatic research: an outcome drawn from routine records is observable and tied to documented care, yet it reflects both underlying activity and whether that activity was recorded. Interpreting a difference in documentation requires attention to record capture and the meaning of documentation as a proxy for wider processes. The registry specifies document types and a follow-up period, but does not report data on completeness of records or the relationship between documentation and other aspects of advance care planning.

The gap between a clearly stated question and absent inferential results is itself important. Without outcome counts, denominators, effect estimates, and uncertainty intervals, readers cannot assess magnitude or precision. The study's completed status and enrollment figure cannot fill that gap. The case underscores why design descriptions and statistical results serve different purposes: the former explain what was intended, while the latter are necessary to evaluate what the data show.

13. 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.

A central trial-specific limitation of the registry record is that it does not report the primary outcome comparison. Group-level endpoint counts, analysis denominators, an effect estimate, and its uncertainty are absent. The record also lists no analysis entries and indicates that the primary outcome includes several categories or time points without one reduced comparison. This prevents evaluation of the reported effect and of the statistical procedure used to obtain it.

The endpoint is based on electronic health record documentation. The registry does not report record completeness, how documents were identified across care delivery systems, or whether the systems captured documentation comparably between groups. Those details could affect ascertainment of the endpoint. The endpoint population excludes those with an advance directive or MO(L)ST at baseline, so the primary outcome does not describe new documentation among that excluded group.

Other design and analysis details are not reported in the registry record, including the unit and procedure of randomization, allocation concealment, assignment ratio, analysis population, missing-data handling, and any adjustment for clustering or other covariates. The usual-care condition is not further characterized. These omissions constrain assessment of implementation, analysis validity, and applicability beyond the settings studied. They should not be filled in by assumption.

14. Related Tutorials

15. Related Statistical Calculators

16. Sources

• ClinicalTrials.gov: Improving Communication for Primary Care Patients — NCT04819191.
• Registry record last updated 2025-03-03; status last verified 2025-02.
• Results first posted 2025-03-03.
• 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.

17. Record Summary

NCT04819191, titled Improving Communication for Primary Care Patients (SHARING Choices), is listed as a completed randomized, parallel-group trial with no masking. The sponsor is Johns Hopkins University, and enrollment is listed as 64915. The registry dates are 2021-03-01 for study start and 2023-11-20 for primary completion.

The behavioral intervention combines a clinic letter, access to an advance care planning facilitator, patient-family agenda-setting, optional portal-registration assistance, and staff education and resources about Alzheimer's Disease and Related Dementias. The comparator is usual care.

The primary endpoint concerns new electronic-record documentation of any advance directive among patients 65 and older without such documentation at baseline, assessed over 1 year. Primary outcome results, analysis details, and the statistical plan are not reported in the registry record. The record therefore describes the study question and measurement but does not permit interpretation of the primary treatment comparison.