This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Minimizing Harm From ADEs by Improving Nurse-Physician Communication (NCT00574990), a registered phase not stated study. The primary outcome is Incident Rate for Communication Events.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00574990 |
| Phase | Phase not stated |
| Condition | Interdisciplinary Communication, Management, Medication Therapy |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 39 |
| Arms in the primary outcome | n/a |
| Lead sponsor | US Department of Veterans Affairs |
| Results posted | Yes |
2. Clinical Question
Population
Providers who had worked at least one year in the VA and were familiar with its electronic health record, CPRS. The listed professional groups are VA physicians, VA nurses and VA pharmacists.
Intervention
No treatment or communication intervention is identified as an assigned intervention. The study examines medication-management communication in inpatient care through focus groups and ethnographic observation.
Comparator
No randomized or like-for-like control comparison is described. The listed professional groups are not presented as intervention and control arms, and allocation is not stated.
Primary question
How often do communication events occur during observation periods involving eligible providers? The primary endpoint is the mean number of events per observation, with the observation period described as approximately two-hours long.
The study concerns the clinical processes involved in sharing medication-management information among nurses, pharmacists and physicians in the inpatient setting. Its focus is communication content and process in relation to clinical care, rather than a comparison of patient outcomes between assigned treatments. The registry describes an exploratory qualitative phase intended to examine perceptions of roles and procedures, followed by observation and coding of specific communication events.
The primary endpoint concerns the frequency of recorded communication events over an observation period. It can describe how much communication was captured during the observed periods, but it does not, by itself, establish whether the communication was complete, accurate, timely or beneficial. The registry also lists a secondary outcome, Overall Involvement in Conversation by Roles, but its numerical results and definition are not reported in the registry record.
The study is marked completed, but numerical primary endpoint results are not reported in the registry record. Consequently, the registered question can be described, while the magnitude and precision of any observed communication frequency cannot be assessed from the posted results.
3. Trial Design
This is a completed study sponsored by the US Department of Veterans Affairs. The registry lists its start as 2008-01 and primary completion as 2009-09, with enrollment of 39. It is not described as a randomized comparison: allocation is not stated, and the professional groups are not a like-for-like control comparison.
The brief summary describes two phases. The first uses focus groups across three sites, with a total of nine groups and 6-8 individuals in each. Discussions were to be tape-recorded and analyzed using qualitative methods. Their stated purpose was to examine perceptions of roles and procedures in medication management and inform development of measures and interventions. Whether every described focus group was conducted, and the qualitative findings, are not reported in the registry record.
The second phase is described as ethnographic observation of specific communication events. The plan called for 400 2-4 hour time slots to be randomly selected over about a 5-week period for nursing staff, and 500 events over a 6-week period for physicians. The summary says events would be recorded and coded, with efforts to minimize interruptions during clinical care. These are descriptions of planned observation activity, not numerical endpoint results. Whether those planned observation schedules were completed as described is not reported in the registry record.
The endpoint description states that observation periods were approximately two-hours long, that some providers were observed more than once, and that communication events were counted per observation period. It does not report the number of completed periods, how repeated observations were handled analytically, or whether the planned observation schedules differed from what was conducted. The registry identifies eligible providers as VA staff with at least one year of VA work experience who were familiar with CPRS.
The record lists VA Physicians, VA Nurses and VA Pharmacists as groups, with respective counts at risk of 12, 19 and 8 in the adverse-event information. Those figures should not be mistaken for randomized treatment arms. The endpoint's results, group-specific event summaries and a detailed statistical analysis plan 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.
Overall Study
| Stage | VA Physicians | VA Nurses | VA Pharmacists |
|---|---|---|---|
| STARTED | 12 | 19 | 8 |
| COMPLETED | 12 | 19 | 8 |
| NOT COMPLETED | 0 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Participants were providers who had worked at least one year in the VA and were familiar with the VA's electronic health record, CPRS.
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.
| Characteristic | Unit | VA Physicians | VA Nurses | VA Pharmacists | Total |
|---|---|---|---|---|---|
| Participants analysed | 12 | 19 | 8 | 39 | |
| Age, Customized: 18 to 75 years | participants | 12 | 19 | 8 | 39 |
| Sex: Female, Male: Female | Participants | NA | NA | NA | NA |
| Sex: Female, Male: Male | Participants | NA | NA | NA | NA |
| Region of Enrollment: United States | participants | 12 | 19 | 8 | 39 |
6. Primary Endpoint
The registry lists the primary outcome as Incident Rate for Communication Events, measured over 6 months.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | mean events per observation |
| Endpoint classification | Event-Rate Endpoint |
The primary endpoint is titled Incident Rate for Communication Events and is expressed as mean events per observation. Communication events were counted within each observation period; the description says those periods were approximately two-hours long. The endpoint therefore summarizes the average number of recorded events across observation periods, rather than the number of providers who experienced an event or a patient-level clinical outcome.
A count per observation period makes the amount of observed communication interpretable in relation to a defined period of observation. In general, expressing event frequency relative to exposure helps distinguish a high event count associated with more observation from a high event frequency during comparable observation. Here, the registry identifies the observation as the unit and gives its approximate duration, but does not report a more detailed exposure adjustment or an endpoint estimate.
The mean can describe the average recorded count, while the standard deviation describes how much counts vary across the observations. These answer different questions: the mean is a measure of central tendency, and the standard deviation describes dispersion. A mean alone would not reveal whether most periods had similar counts or whether the average was influenced by periods with unusually many events.
Communication frequency is not equivalent to communication quality or appropriateness. The endpoint does not directly measure whether medication information was correct, whether a potential medication problem was prevented, or whether patient health changed. The registry's numerical result for this endpoint is not reported in the registry record, so neither the average nor its variability can be assessed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive limitation is that the registry record gives the primary endpoint definition but no numerical result for it. It is therefore not possible to describe the observed mean number of communication events per observation, its variability, or differences among professional roles. No confidence interval or test result for the primary endpoint is reported in the registry record. The completion status indicates that the study is marked completed; it does not supply the missing endpoint estimates.
The listed groups are professional roles in an observational study, not randomized arms. The record explicitly indicates that this is not a randomized comparison, that allocation is not stated, and that the arms are not a like-for-like control comparison. Any comparison between roles would need to account for differences in who was observed, the settings and opportunities for communication, and observation frequency. Those details and any adjusted or unadjusted role comparisons are not reported in the registry record.
The endpoint is a count per observation period, and some providers were observed more than once. Repeated observations from the same provider may be statistically related; treating every period as wholly independent could misrepresent uncertainty. The registry does not report whether repeated observations were modeled as clustered, averaged by provider, or handled in another way. This is a question about analysis, not evidence that a particular approach was used.
The brief summary describes focus groups and planned ethnographic observation, but the numerical summaries needed to evaluate those data are absent. The record also lists Overall Involvement in Conversation by Roles as a secondary outcome, without reporting its numerical results. No account of coding agreement, the operational definition of a communication event, or the completeness of observation periods is reported in the registry record. These omissions limit assessment of how consistently events were identified and what the recorded counts represent.
The posted adverse-event figures list zero serious events and zero other events affected in each professional group. These are registry safety counts, not evidence about the primary communication endpoint. The record does not provide event narratives or explain the collection and attribution process. Death figures are not reported in the registry record.
The study's sample-size assumptions describe a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms and a normal approximation. The effect estimate and the numerical planning results are not reported in the registry record. Those illustrations, even if displayed elsewhere with the record, are not evidence of observed power and do not establish that this observational study had a particular ability to detect differences.
Overall, the record supports a description of the research question and planned observation approach, but not a conclusion about the measured frequency or distribution of communication events. The absence of posted outcome estimates means statistical precision and the magnitude of any role-related pattern cannot be judged.
9. Statistical Methods Explained
The endpoint is a count of communication events within an observation period, summarized as a mean number of events per observation. The registry also specifies standard deviation as the dispersion measure. The concepts below explain how such statistics are generally interpreted; the analysis actually used for this study is not reported in the registry record unless explicitly described.
What does a mean events-per-observation value describe?
A mean is the arithmetic average of the recorded counts across the observations included in an analysis. It provides a compact description of the typical count, but it can conceal variation. For example, observation periods could have counts clustered near the mean, or the mean could reflect a mixture of periods with few events and periods with many. The registry does not report the observed mean or the distribution of counts, so the pattern cannot be assessed for this study.
The observation period is the denominator-like unit that gives the count context. In general, event rates are interpreted in relation to time or another exposure unit, because opportunities to observe events can differ. The registry describes periods as approximately two-hours long and says counts were made per period. It does not report exact period durations, an exposure-adjusted rate, or whether differences in duration were incorporated in analysis.
What does the standard deviation add?
Standard deviation describes the spread of individual observations around their mean. A larger spread indicates more variation among the observed counts; a smaller spread indicates that counts are more concentrated around the mean. It is not the same as the standard error, which describes uncertainty in an estimated mean. Nor is it a confidence interval, which gives a range of values compatible with data under a specified method and assumptions. The registry identifies standard deviation as the dispersion measure but does not report its value or a confidence interval for the endpoint.
As general statistical context, count outcomes often have variability that changes with their mean, and some count data vary more than a simple Poisson model would expect. Over-dispersion is the term for variability beyond that model's expectation. If over-dispersion is present and ignored, estimated uncertainty can be too small. Whether event counts in this study were over-dispersed, and what model was used, are not reported in the registry record. No particular distribution or model should therefore be attributed to the investigators.
Why might repeated observations matter?
The endpoint description notes that some providers were observed more than once. Observations from the same person may share characteristics and therefore be correlated. In general, statistical methods for clustered data account for the fact that multiple observations from one person may carry less independent information than observations from different people. The record does not say whether repeated observations were linked analytically, whether counts were aggregated by provider, or whether another method was used. It also does not report the number of observations contributing to the primary endpoint.
There may also be differences in observation opportunity across professional roles. The summary describes planned observation activity for nursing staff and physicians, while pharmacists are included as a provider group. It does not report a pharmacist observation schedule or the completed exposure time by role. This makes it important not to treat role-specific raw counts as directly comparable without knowing their denominators and the analysis approach. No role-specific event rates are reported in the registry record.
What can a confidence interval tell a reader?
In general, a confidence interval conveys uncertainty around an estimate, conditional on the statistical method and its assumptions. A narrower interval indicates greater precision under that method; a wider interval indicates more uncertainty. It does not establish that all values in the interval are equally plausible, and it does not resolve bias from an unsuitable sampling or measurement process. No interval for the primary endpoint is reported in the registry record, so its precision cannot be evaluated.
Likewise, a significance test, if performed, would address compatibility of data with a specified null hypothesis under the chosen model. It would not by itself convey the size or practical meaning of a difference. The registry does not report a primary endpoint test, its p-value, or the hypothesis tested. It is not appropriate to infer statistical significance from the study's completed status or from its planning assumptions.
How should the sample-size illustration be read?
The record's sample-size assumptions describe planning illustrations based on the observed effect, not the trial's own design. They state a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. The record also distinguishes total events for time-to-event calculations from participants per arm for other calculations. The numerical effect and resulting planning values are not reported in the registry record.
Those assumptions do not convert this study into a randomized two-arm trial. The registry describes professional groups and observational communication measurements, with no stated allocation. A hypothetical sample-size calculation can illustrate how assumptions affect required sample size, but it does not establish the achieved precision or power of the actual study. Sample sizes derived from an observed effect are planning illustrations, never observed power.
More broadly, the reliability of an event-count analysis depends on clear event definitions, consistent coding, complete observation, and an analysis that reflects the observation structure. The brief summary says communication events were to be recorded and coded, but coding procedures, quality checks and analytic details are not reported in the registry record. These are relevant uncertainties when interpreting any event-frequency estimate.
10. Multiplicity, Missing Data and Analysis Populations
The record lists a primary endpoint, Incident Rate for Communication Events, and a secondary outcome, Overall Involvement in Conversation by Roles. It also describes qualitative focus groups and coded observations. The registry does not report whether multiple outcomes, role comparisons or other analyses were planned, or how the analysis handled the possibility of multiple statistical tests. A multiplicity adjustment, if any, is not reported in the registry record.
Multiplicity matters in general when many hypotheses are tested: the chance of at least one apparently unusual result can increase as the number of tests grows. The concern depends on which comparisons were prespecified and how results were interpreted. Those details are not reported, so neither the extent of multiplicity nor any correction can be evaluated. The number of analyses recorded is 1, but the record does not identify the detailed model or establish how that entry relates to all analyses conducted.
The registry does not report missing-data counts for the primary endpoint, incomplete or interrupted observation periods, exclusions after observation, or procedures for handling missing values. The brief summary says efforts would be made to minimize interruptions during clinical care; it does not report how many interruptions occurred or how their effects were handled. Whether observations were excluded, retained for partial periods or otherwise processed is not reported in the registry record.
The analysis population is not described in sufficient detail to establish which providers or observation periods contributed to each endpoint. Some providers were observed more than once, but the handling of repeated observations is not reported. The record does not state whether all enrolled providers were included in each analysis or how eligibility deviations were treated. These gaps make it difficult to assess the denominator behind an estimate or whether the analyzed observations represent the intended population.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| VA Physicians | 0 | 12 | 0.0% |
| VA Nurses | 0 | 19 | 0.0% |
| VA Pharmacists | 0 | 8 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| VA Physicians | 0 of 12 |
| VA Nurses | 0 of 19 |
| VA Pharmacists | 0 of 8 |
The registry's adverse-event information lists VA Physicians with 12 at risk, 0 serious events affected and 0 other events affected; VA Nurses with 19 at risk, 0 serious events affected and 0 other events affected; and VA Pharmacists with 8 at risk, 0 serious events affected and 0 other events affected. These are group-specific registry figures and should not be combined or treated as treatment-arm comparisons.
A recorded zero means that no affected participants are listed for that event category in the registry data. It does not establish that the study could rule out all possible harms or that every type of event was collected with equal completeness. The record does not report detailed event definitions, surveillance procedures, attribution rules or the duration of safety follow-up. Death counts are not reported in the registry record.
This study examines communication processes rather than a randomized treatment comparison. The adverse-event figures therefore do not provide a comparative safety estimate for an intervention. They also do not replace the missing communication-event endpoint results. Interpretation should remain limited to what the registry actually records: the listed at-risk counts and zero affected counts in the serious and other categories.
12. What the Result Does, and Does Not, Mean
This record describes research on how medication-management information is shared among nurses, pharmacists and physicians in inpatient care. It identifies a primary endpoint based on the mean number of communication events per observation and a secondary outcome concerning involvement in conversation by roles. It also outlines focus groups and planned ethnographic observation. These details establish the subject and measurement approach, not the study's numerical findings.
The posted results do not report the primary endpoint estimate, its standard deviation, a confidence interval, or a comparison among professional roles. As a result, the recorded data cannot be used to characterize how frequently communication events occurred or how precisely that frequency was estimated. The secondary outcome's numerical results are also not reported in the registry record. No conclusion about the strength or direction of a role-related pattern follows from the available entries.
Even if event counts were available, frequency would not alone demonstrate communication quality, accuracy or clinical impact. More recorded events do not necessarily mean better communication, and fewer recorded events do not necessarily mean worse communication. The endpoint measures counts during observation periods, not whether medication decisions were correct or whether patient outcomes changed. The registry does not report a patient outcome analysis.
The record also does not describe a randomized intervention comparison. The professional groups should not be read as treatment and control arms, and any observed differences could reflect differences in roles, opportunities, sampled settings or observation time. The registry does not report enough analysis detail to determine how such factors were handled.
The most defensible reading is therefore descriptive: a completed study was registered to examine communication processes, with an event-count endpoint and qualitative and observational components. The available registry record does not provide the outcome estimates required to judge the size, variability or precision of the measured communication frequency. The safety counts are separate registry entries and do not fill that evidentiary gap.
13. Why This Trial Matters Statistically
Statistically, the study is notable for focusing on communication events as count data collected during observation periods. The observation period supplies an interpretable unit for the event count, and the endpoint specifies both a mean and a dispersion measure. This makes clear that understanding an average count also requires attention to the variation among observations.
The design description raises important issues about how observational data are structured. Some providers were observed more than once, so observations may not be independent. Professional roles may also differ in their opportunities for communication and in how much observation they received. Appropriate comparison therefore depends on transparent denominators and methods for handling repeated observations and differences in exposure. Those analytic details and the endpoint results are not reported in the registry record.
The study also combines qualitative exploration with event recording and coding. In general, qualitative work can help define what matters for measurement, while coded observation can quantify a specified behavior. The brief summary states that focus-group findings were intended to inform measures and interventions. The registry does not report the resulting themes, coding rules or consistency checks, so the relationship between the qualitative work and the event measure cannot be evaluated from the posted results.
Finally, this record illustrates why design information and outcome reporting serve different purposes. The registry contains a substantive question, eligibility description, planned observation procedures and an endpoint definition. But without estimates and uncertainty measures, readers cannot assess the observed frequency or its precision. A completed status and a detailed description of planned work do not substitute for numerical results.
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 main limitation for interpreting the study is the absence of numerical primary endpoint results from the registry record. The mean event count per observation and its standard deviation are not reported, nor is a confidence interval or a statistical test. Numerical results for the listed secondary outcome are also absent. This prevents assessment of effect magnitude, variability and precision.
The registry describes a non-randomized study and does not state allocation. The professional groups are not a like-for-like control comparison. Role-based differences, if analyzed, could reflect differences in duties, opportunities to communicate, observation patterns or other factors; the registry does not report whether these were measured or adjusted for. No causal treatment comparison can be inferred from the design description.
Although the brief summary sets out planned focus-group and observation activity, it does not establish whether all planned procedures were completed as described. The number of completed observation periods, actual observation time by role, event definitions, coding procedures and quality checks are not reported in the registry record. The endpoint description says some providers were observed more than once, but the analysis of repeated observations is not reported. These gaps limit evaluation of denominators, measurement consistency and uncertainty.
Missing-data handling, analysis populations, multiplicity procedures and a detailed statistical plan are not reported in the registry record. The planning assumptions refer to equal allocation between two arms, but the study is described as observational and does not specify such an allocation. The numerical planning illustrations are not reported, and they cannot establish the achieved precision of the study.
The safety entries show zero affected counts in the listed serious and other categories for each professional group, but the collection and follow-up procedures are not described. Death counts are not reported in the registry record. These limitations do not negate the study question; they define what can and cannot be concluded from the registered information.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Minimizing Harm From ADEs by Improving Nurse-Physician Communication — NCT00574990.
- Registry record last updated 2015-06-09; status last verified 2015-05.
- Results first posted 2015-06-09.
- 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.
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18. Record Summary
NCT00574990 is a completed study sponsored by the US Department of Veterans Affairs, with enrollment of 39. Its start is listed as 2008-01 and primary completion as 2009-09. The study examines inpatient medication-management communication among VA physicians, nurses and pharmacists familiar with CPRS and with at least one year of VA work experience.
The brief summary describes focus groups followed by ethnographic observation and coding of communication events. The primary endpoint is the mean number of communication events per observation, with standard deviation as the dispersion measure; observation periods were approximately two-hours long, and some providers were observed more than once.
Numerical primary and secondary outcome results, detailed analysis methods, missing-data procedures and multiplicity handling are not reported in the registry record. The listed safety information records zero serious and zero other events affected in each professional group; deaths are not reported in the registry record.