Barriers to Screening Breast MRI Utilization Among Patients at Elevated Risk: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Barriers to Screening Breast MRI Utilization Among Patients at Elevated Risk (NCT04257474), a registered phase not stated study. The primary outcome is Reporting Receipt of MRI Breast Screening at Any Time.

2. Clinical Question

The study’s stated purpose was to develop an explanatory framework for breast MRI utilization that could inform future interventions. It planned to examine factors organized under the Health Services Utilization Model: predisposing characteristics, enabling resources, and perceived need. Examples named in the registry record include knowledge and health or cultural beliefs; social support and cost or insurance coverage; and perceived susceptibility and provider recommendation.

This is a utilization study, not a randomized comparison of screening strategies. Its clinical question concerns reported past screening and factors that may be associated with use. The record does not establish that any particular factor caused screening behavior, nor does it report the direction or strength of an association. The interviews were intended to add context about participants’ decisions, not to provide a separate comparison of outcomes.

3. Trial Design

The registry record describes a completed mixed-methods study, with a self-report survey and qualitative interviews. Its stated overall aim was to develop an explanatory framework for use of screening breast MRI among people at elevated risk. The Health Services Utilization Model guided the selection of participant-level factors for examination, grouped as predisposing characteristics, enabling resources, and perceived need.

The registry lists an enrollment of 265. The arm description for assessing the model says that 150 women with high lifetime breast cancer risk would be recruited from mammography and primary care clinics. It also describes randomly selecting 30 participants from group 1 for semi-structured interviews. These descriptions do not report how many participants actually completed the survey or interview, or how many contributed data to each analysis. The relationship between the registry enrollment and the recruitment numbers in the arm descriptions is not explained in the registry record.

The primary outcome is participant-reported receipt of breast MRI screening at any time in the past, assessed at baseline. The survey data from participants who completed self-report surveys were analyzed as one group. Interviews were intended to explore factors affecting screening utilization and participants’ decisions. The record explicitly says the interviews were not intended to compare groups.

Although the registry labels the survey and interviews as behavioral interventions, their descriptions identify them as study activities for collecting information. The record does not describe a randomized treatment assignment or a control condition. Allocation is not stated, and the arms are not a like-for-like control comparison. The study status is completed; the start date is 2020-01-30 and the primary completion date is 2022-01-19. The registry does not report a detailed analysis plan or the results of 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: This study uses a mixed-methods design. All data from participants who completed self-report surveys were analyzed as one group. Semi-structured interviews were done to understand more about the patients decisions, not to compare any group against another.

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 Reporting Receipt of MRI Breast Screening at Any Time, measured over Baseline.

The primary endpoint is the percentage of participants reporting receipt of screening breast MRI at any time in the past. It is described as a baseline measure based on participant report. In practical terms, it records whether survey respondents said they had previously received screening breast MRI; it is not a measure of a new screening event observed during follow-up.

A percentage can describe how common a reported behavior is within the analyzed survey population. In a utilization study, this kind of measure can characterize screening history and provide an outcome to examine alongside participant-level factors. The registry’s stated framework includes predisposing characteristics, enabling resources, and perceived need. The endpoint therefore aligns with the study’s aim of understanding factors associated with screening use, rather than evaluating a treatment’s effect.

Interpretation depends on knowing who answered the survey and how many responses contributed to the endpoint. Those details, the endpoint percentage, and any uncertainty interval are not reported in the registry record. The wording “at any time in the past” also means the outcome is a report of prior receipt, not a time-to-event outcome or a count of screening examinations. The record does not specify further measurement details, such as how a reported MRI was verified or how missing responses were handled.

Participant report is useful for describing respondents’ reported screening histories, but the registry entry alone cannot establish the accuracy or completeness of those reports. Nor does the endpoint by itself explain why screening was or was not received. It must be interpreted as a descriptive utilization outcome, with any associations requiring separate results and analysis details. Neither the outcome value nor those analyses are reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a mixed-methods design: survey responses were intended to quantify reported screening and participant characteristics, while semi-structured interviews were intended to explore decisions in more depth. These methods can address related but distinct questions. Survey statistics can describe patterns across respondents and estimate associations among measured variables. Interview material can provide context about how participants understand or experience those factors. The registry record does not report the analyses or findings from either component.

What does a percentage describe?

For a binary outcome, each participant’s response is classified into one of two categories, such as reporting or not reporting receipt of a screening procedure. The percentage describes the share of the analyzed respondents in the category of interest. Its interpretation depends on the denominator: who was eligible, who responded, and whose data were included. The record identifies the endpoint as a percentage of participants but does not report the observed value or the analysis denominator. It is therefore not possible to assess the prevalence estimate or its precision from the registry entry.

A confidence interval, in general, expresses uncertainty around an estimate under the assumptions of the statistical method. A narrower interval indicates greater precision, while a wider interval indicates less precision. It does not remove possible bias from participant selection, measurement, or missing data. No confidence interval for the primary outcome is reported in the registry record, so neither the estimate’s precision nor a plausible range of values can be assessed.

How should associations be read?

The study intended to examine factors that may be associated with screening outcomes, drawing on predisposing characteristics, enabling resources, and perceived need. An association describes how an outcome varies with a measured factor in the analyzed data. It does not, on its own, show that the factor caused the outcome. That distinction matters especially when an outcome concerns screening received at any time in the past: the record does not specify when each candidate factor arose relative to the reported screening history.

Adjustment for other variables can sometimes help distinguish an association from differences explained by measured covariates. However, the registry record does not describe an adjustment strategy, a model specification, or which variables were included in any analysis. It would be inappropriate to infer a particular regression model or claim that confounding was controlled. No estimates, standard errors, intervals, or significance tests for associations are reported.

What does the planning note mean?

The registry’s planning note describes illustrations 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 to detect is described as a stated fraction of the observed effect. It also distinguishes participant counts per arm for non-time-to-event outcomes from total event counts for time-to-event outcomes. Those are planning assumptions, not results of the study. The record does not report the observed effect or numerical planning estimates, so no sample-size illustration can be interpreted from these details alone.

A planning calculation asks what sample size might be needed under specified assumptions. It is not a measure of the study’s observed power. Observed power is not a substitute for reading an estimate and its uncertainty, and a planned sample size does not show that the study achieved a particular precision. The enrollment entry and arm descriptions are not, by themselves, evidence that the outcome analyses used those numbers.

Why does the design matter?

The registry does not describe a randomized control comparison. Survey participants were analyzed together, and interviews were used to understand decisions rather than compare groups. Accordingly, statistical interpretation should focus on description and associations rather than treatment contrasts. The term “randomly select” in the interview arm description refers to selecting interview participants from group 1; it does not describe random allocation to competing screening strategies.

For binary outcomes, an analysis might report a proportion or compare proportions across defined groups, but the record does not report such a comparison or specify that one was performed. For interview data, qualitative interpretation typically examines recurring themes and variation in accounts; the registry does not state a coding procedure, analytic framework for the interviews, or themes. General statistical and qualitative principles cannot substitute for trial-specific methods and results that are absent from the record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists seven outcome measures and names five secondary outcomes in addition to the primary outcome description. The available record does not identify the other measures or report results for any of them. It also does not state how many hypotheses were tested, which outcomes were designated for confirmatory inference, or whether any adjustment for multiple comparisons was planned or used. Those multiplicity procedures are not reported in the registry record.

In general, examining multiple outcomes or associations creates more opportunities for apparently notable findings to occur by chance. A prespecified analysis plan and an explicit approach to multiplicity help readers distinguish primary questions from exploratory analyses. Without those details or reported test results, the statistical evidence across outcomes cannot be evaluated. No p-values or confidence intervals are reported for the listed secondary outcomes.

Missing-data methods are also not described. The record does not report how many participants completed the survey, how many had a response for the primary endpoint, whether any items were left unanswered, or how incomplete records were handled. It does not state whether analyses used complete cases, imputation, or another method. The analysis denominator and the possibility that respondents differed from nonrespondents therefore cannot be assessed from the registry entry.

The primary outcome population is described as participants who completed self-report surveys, analyzed as one group. This identifies the broad analysis population but does not give its size or clarify whether all such participants had usable primary-outcome data. The interview participants were selected from group 1, but their number actually interviewed and the handling of incomplete interviews are not reported. The registry reports zero analyses; that means no analysis entries are listed in the record, not that the reason for their absence is known.

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

The registry record establishes that the study was completed and describes its goal: to develop an explanatory framework for breast MRI utilization among people at elevated risk. It identifies a primary outcome based on participant reports of screening received at any time in the past and describes a survey and qualitative interviews. It also names candidate factors related to beliefs, resources, and perceived need. These details define the research question and planned approach.

They do not establish the observed frequency of reported breast MRI screening. The primary outcome percentage, its denominator, and any measure of uncertainty are not reported in the registry record. The record also does not report which factors were associated with screening or how strong or precise any association was. Thus, no conclusion about the prevalence of use, the presence of a particular barrier, or the relative importance of the named factors can be drawn from the posted registry information.

The study is not described as a randomized comparison of interventions. Its arms are not like-for-like controls: the survey data were analyzed as one group, while interviews were intended to explore decisions. The registry does not support interpreting the study as evidence that a particular intervention changed MRI use. Nor can an association between a participant characteristic and reported past use, if one were later reported, alone establish causation.

Participant-reported screening history is the stated outcome. The record does not say whether reports were independently verified, how missing answers were handled, or how many participants contributed to the primary analysis. Those omissions limit assessment of measurement quality, selection, and precision. The registry enrollment and the numbers in the arm descriptions do not replace a reported analysis denominator.

The findings that would be needed for a fuller interpretation include the primary outcome estimate, its uncertainty, the analyzed population, methods for handling missing data, and results for the stated explanatory factors. Those are not reported in the registry record. The study’s stated purpose may inform future research questions, but the available entry does not establish which framework factors were supported by observed results.

12. Why This Trial Matters Statistically

Statistically, this study matters because it frames screening utilization as an outcome to be explained through several domains rather than treating access or decision-making as a single factor. The registry’s Health Services Utilization Model includes predisposing characteristics, enabling resources, and perceived need. That framework can organize measurement and help researchers state which kinds of participant-level variables they intend to examine.

The mixed-methods approach also reflects two different evidence needs. A survey can describe reported screening histories and examine how measured factors vary with those histories. Interviews can explore participants’ reasoning and the context behind their decisions. Bringing those approaches together can make an explanatory framework more informative, but the registry record does not report how the two forms of evidence were integrated or what they found.

The design also makes clear why a utilization association should not be mistaken for a causal treatment effect. Survey responses concern past screening, and the record does not specify the timing of every proposed explanatory factor relative to that history. Without a randomized comparison or a reported strategy for addressing confounding, associations would need cautious interpretation. The registry explicitly describes survey participants as one analysis group and interviews as exploratory rather than comparative.

Finally, the record illustrates the distinction between registering a research question and reporting its statistical answer. It includes a primary endpoint and names secondary outcomes, yet does not report outcome estimates, uncertainty, or the analysis methods. Without those elements, readers cannot assess precision, missingness, multiplicity, or the strength of evidence. The registry entry is useful for understanding the study’s intended scope, but the statistical contribution cannot be evaluated from the reported results because results are not included.

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.

The main trial-specific limitation of the available record is that it does not report the primary endpoint value or any outcome estimates. There is no reported confidence interval or other measure of uncertainty. Without an estimate and its denominator, the frequency of reported screening and its precision cannot be assessed.

The registry gives an enrollment of 265, while the arm descriptions refer to recruiting 150 women for the model assessment and selecting 30 participants for interviews. It does not explain how those numbers relate to actual participation or analysis. The number of survey completers, the number with usable primary-outcome data, and the number interviewed are not reported. This prevents readers from determining the analysis populations or evaluating attrition and completeness.

The primary outcome is participant-reported receipt of screening breast MRI at any time in the past. The record does not specify whether reports were verified, how the question was administered, or how recall or misunderstanding was addressed. It also does not provide the timing of the proposed explanatory factors relative to the past screening outcome. These gaps limit interpretation of measurement and directionality.

The record does not report model specifications, covariate adjustment, missing-data handling, multiplicity procedures, or qualitative analysis methods. Although it names seven outcome measures, it lists only five secondary outcomes and does not provide results for them. It reports zero analyses, without explaining whether analyses were conducted but not entered in the registry. These limitations concern the information available in the registry record; they do not establish that the study itself lacked analyses or that its data were incomplete.

14. Related Tutorials

15. Related Statistical Calculators

16. Sources

• ClinicalTrials.gov: Barriers to Screening Breast MRI Utilization Among Patients at Elevated Risk — NCT04257474.
• Registry record last updated 2024-03-18; status last verified 2023-08.
• Results first posted 2024-03-18.
• 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

The registry record describes a completed mixed-methods study, NCT04257474, titled “Barriers to Screening Breast MRI Utilization Among Patients at Elevated Risk.” Its stated aim was to develop an explanatory framework for breast MRI utilization, guided by the Health Services Utilization Model. The study used a self-report survey and semi-structured qualitative interviews.

The primary outcome was participant-reported receipt of breast MRI screening at any time in the past, assessed at baseline. The survey population was analyzed as one group; interviews were intended to explore decisions rather than compare groups. The record lists an enrollment of 265 and describes recruitment of 150 women for the model assessment and selection of 30 participants for interviews. It does not report actual analysis counts.

Five secondary outcomes are named: reported receipt of mammogram, ultrasound, chemoprevention, genetic testing, and genetic counseling. Although the record lists seven outcome measures, it does not identify all of them. The primary outcome result, secondary outcome results, statistical analysis details, and missing-data methods are not reported in the registry record.