Functional MRI Use in Prostate Radiation Treatment Planning: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Functional MRI Use in Prostate Radiation Treatment Planning (NCT01985932), a na na study. The primary outcome is Number of Participants With Adverse Events.

2. Clinical Question

3. Trial Design

The registry describes a prospective study evaluating functional MRI during prostate radiation treatment planning. Its official title specifies non-endorectal coil functional MRI and the identification of intraprostatic tumor. The listed intervention is MRI, classified as a device, and the arm description says that participants received functional MRI during radiation therapy treatment planning.

This is a single-group study, not a randomized trial. Allocation is recorded as NA, and the registry explicitly cautions that the arm is not a like-for-like control comparison. The record does not identify a concurrent group receiving another imaging or planning approach. As a result, the study design can describe what was recorded among the participants in the MRI group, but it cannot by itself estimate a comparative effect against a control group.

The registry lists enrollment of 15 participants and identifies prostate cancer as the condition. Its summary describes eligible subjects as male adults aged 18 or older with a prostate cancer diagnosis and treatment plans at the Department of Radiation Oncology. The University of Pennsylvania Health System is named as the study setting, and Abramson Cancer Center at Penn Medicine is the sponsor.

The record lists a start date of 2012-07, primary completion in 2014-04, and status as completed. The brief summary says the study was projected to run for 18 months; that is a projection, not a report of actual study duration. The phase is recorded as NA. The registry does not report details of recruitment, image assessment, treatment decisions, or follow-up completion beyond the primary outcome timeframe.

The primary outcome is the number of participants with adverse events, with a stated timeframe of 2 years. This outcome describes safety-event counts; it does not directly assess the accuracy of tumor identification or the effect of MRI on radiation planning. The registry record does not report an additional outcome analysis that would answer those efficacy or imaging-performance questions.

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

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 Participants With Adverse Events, measured over 2 years.

The primary endpoint is the number of participants with adverse events during the stated timeframe of 2 years. It is expressed as a count of participants, rather than as a measure of how often an event recurred or how severe an event was. The posted safety results separately list serious and other adverse-event categories for the Functional MRI group.

Participant counts are useful for describing how many people in a study experienced an event. They differ from event counts: one participant could potentially experience more than one event, but the endpoint as titled concerns participants with events. The registry record does not provide event narratives, dates of occurrence, severity gradings beyond the serious/other distinction, or a detailed definition of which events qualified for each category.

Safety monitoring is relevant when a study introduces a procedure or device into clinical planning. A count can communicate whether any participants were recorded as affected in the reported categories, while the denominator indicates how many were listed as at risk. Such counts are descriptive and should be interpreted in light of cohort size, follow-up, event definitions, and completeness of reporting.

In this record, 15 participants are listed at risk in each safety category, and 0 are listed as affected in either category. Those observations describe the registry entries for this cohort. They do not establish that the risk of an event is zero, and they do not answer whether functional MRI identifies tumor accurately or changes treatment planning. The registry record does not report a separate imaging-accuracy endpoint or an analysis relating imaging findings to clinical outcomes.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The statistical information in the registry is limited. The study is listed as single group, with enrollment of 15 and one outcome measure. The primary outcome is a count of participants with adverse events, and the registry lists no analyses. The interpretation should therefore focus on what a participant count conveys and on what cannot be inferred without a comparison group or an uncertainty estimate.

What does a count of participants measure?

A participant count records how many people meet an outcome definition at least once during the relevant observation period. It is different from the total number of events: if a person experiences repeated events, a participant-level outcome still counts that person as affected rather than counting every occurrence. The registry's primary outcome title specifies participants with adverse events, and its unit is participants. The record does not give event-level details or a fuller operational definition of the endpoint.

The posted safety information lists 15 participants at risk and 0 affected for serious adverse events, and 15 at risk and 0 affected for other adverse events. These are counts, not rates calculated over person-time. The record does not report person-time, individual follow-up durations, or whether every participant was observed for the entire stated timeframe. It also does not provide event dates or descriptions.

Why does the study design matter?

A comparison estimates how outcomes differ between groups under specified conditions. In a randomized comparison, random assignment is intended to make groups comparable on average, although a trial still requires careful measurement and analysis. General statistical principle: without a suitable comparison group, observed outcomes in a single group cannot separate the effect of an intervention from other influences, such as background event occurrence or selection of participants.

This record identifies a single Functional MRI group and says the study is not a randomized comparison. There is no reported control arm. Thus the adverse-event counts describe what was recorded among MRI participants; they do not estimate a difference between MRI and another approach. The same design limitation applies to conclusions about tumor identification: a comparative claim would require relevant imaging or clinical outcome data and an appropriate comparison, neither of which is reported as an analysis.

How should zero counts be understood?

A zero observed count means that no participant in the listed denominator was recorded as affected in that category. It is not an estimate proving that the event cannot occur. General statistical principle: with a finite sample, a zero count can occur even when the event is possible in a larger population. An interval estimate could describe uncertainty around a proportion or rate, but the registry record does not report such an interval or a formal estimate.

The number at risk is essential context for any count. Here the registry lists 15 at risk in each of the two categories. The record does not state whether these denominators reflect participants with complete follow-up, all enrolled participants, or another analysis population. Because the denominator definition and follow-up completeness are not described, the result should be quoted as posted rather than reframed as a fully ascertained population risk.

What would an inferential analysis add?

An inferential analysis can estimate an outcome quantity and quantify its uncertainty under specified assumptions. A confidence interval, in general, gives a range of values compatible with the data and method; it is not a guarantee that a particular value is correct. A hypothesis test evaluates data against a specified null hypothesis, but its meaning depends on the question, model, and analysis plan. No confidence interval, test, adjusted estimate, or model is reported in the registry record.

For a binary participant outcome, analysts might in general summarize the count and denominator as a proportion and, where appropriate, calculate an interval. That description is general statistical background, not an additional result for this study. No proportion or interval should be inferred beyond the posted counts. The record also does not specify an analysis method for missing outcomes, repeated events, or follow-up that differs among participants.

What do planning assumptions mean?

Power and sample-size calculations are planning tools. In general, they require assumptions about the outcome, effect to detect, significance level, allocation, and analysis method. The registry's planning assumptions describe an illustration using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the target effect stated as a fraction of an observed effect. These are illustration assumptions, not reported features of this single-group study's design.

Sample-size illustrations do not establish observed power and do not turn a single-group study into a randomized comparison. They also do not provide evidence that a study detected an effect. Because the registry record reports no analysis and no comparative effect estimate, a hypothetical two-arm planning framework should be kept separate from interpretation of the posted safety counts. The registry does not report the trial's own sample-size justification.

What details are absent?

The registry record does not report an analysis plan, multiplicity approach, analysis populations, missing-data method, or outcome-specific inferential analysis. It does not give a fuller definition of adverse events, the process used to collect them, or details sufficient to assess whether all participants had complete observation across the stated timeframe. These omissions do not alter the recorded counts, but they constrain evaluation of their precision and completeness.

The appropriate statistical reading is consequently modest: report the listed denominators and zero affected participants in both safety categories, recognize the single-group design, and avoid claims about comparative effects, event-free risk, or imaging performance that the registry results do not estimate.

10. Exact Estimates for Each Arm

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

R code and output

arm    <- c("Functional MRI")
n      <- c(15)
events <- c(0)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Functional MRI  15  0  0.0  0.0  21.8  0.0  20.4  0.2  20.6

11. Multiplicity, Missing Data and Analysis Populations

Multiplicity concerns the interpretation of several statistical tests or outcomes considered together. When many hypotheses are tested, the chance of obtaining at least one apparently notable result can increase; statistical methods may be used to manage that issue, depending on the study question and analysis plan. The registry lists one outcome measure and no analyses. It does not report whether additional analyses were planned, whether multiple time points or subgroups were examined, or whether any multiplicity procedure was specified. No multiplicity adjustment is reported in the registry record.

The record also does not describe missing-data handling. It does not state whether all enrolled participants completed the stated 2-year timeframe, whether adverse-event information was unavailable for any participant, or how incomplete follow-up would be represented in the reported counts. The listed at-risk denominator is 15 for both safety categories, but that alone does not establish the completeness or duration of observation for each participant.

Analysis populations are not defined. The registry does not say whether the results use all enrolled participants, only those who received the planned imaging, or another group. It does not report exclusions from analysis or reasons for any unavailable observations. These details matter because a count's meaning depends on who was included and how missing outcomes were treated.

There is no reported inferential analysis to assess, and no stated statistical plan against which to evaluate selective reporting. The posted counts can be described as recorded, but the registry record does not establish how missingness, multiple questions, or analysis populations were handled.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The safety results list the Functional MRI group with 15 participants at risk for serious adverse events and 0 affected. The other-adverse-event category also lists 15 participants at risk and 0 affected. The outcome timeframe is stated as 2 years.

These entries indicate that no participant was recorded as affected in either listed category in the posted results. They do not show that the underlying chance of an adverse event is zero. General statistical principle: a zero count in a finite group is compatible with uncertainty about what might occur in a broader population. The registry does not report a confidence interval or another measure of uncertainty for these counts.

The record does not give descriptions of events, collection procedures, severity criteria beyond the serious/other categories, or details of follow-up completeness. Nor does it explain the relationship between the two categories. The figures should therefore be read as separate posted category counts, not combined into a new total or interpreted as evidence about all possible harms.

Because this is a single-group study with no reported control group, the safety counts cannot establish whether event occurrence differs from another planning approach. They describe the recorded results for the participants at risk in this group.

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

The study addresses the use of functional MRI during prostate radiation treatment planning, with the official title focusing on non-endorectal coil imaging and identification of intraprostatic tumor. The reported primary outcome, however, is the number of participants with adverse events. The posted safety results list 0 affected participants among 15 at risk in each of the serious and other adverse-event categories.

That information is useful as a description of what the registry recorded for this group. It indicates that no participants were listed as affected in either category. It does not demonstrate that adverse events are impossible, that no unrecorded events occurred, or that the same result would be expected in a larger or different population. The registry record does not report uncertainty intervals or details of follow-up completeness that would clarify the precision of the counts.

The result also does not establish whether functional MRI accurately identifies tumor, changes the radiation plan, or improves any clinical outcome. Those questions require outcome measures and analyses directed at imaging performance or treatment consequences. The registry record does not report such an analysis. The study's title and stated purpose describe an evaluation of tumor identification, but the posted primary outcome is safety-event count.

There is no randomized comparison or separate control group. Therefore, the counts cannot be interpreted as a difference between MRI and another approach, and they cannot show that MRI caused the observed absence of recorded events. The single-group results are descriptive rather than comparative.

In general, statistical conclusions depend not only on observed counts but also on how outcomes are defined, who is included, whether observation is complete, and what analysis was planned. Those details are not reported in the registry record. The defensible interpretation is limited to the event counts as posted, with the study design and missing analytical details kept in view.

14. Why This Trial Matters Statistically

This study is statistically notable because its stated purpose concerns functional MRI use in radiation planning, while its reported primary endpoint is a safety count. That distinction matters: a study can address a clinical or technical motivation in its title and summary without the registry results measuring every aspect of that motivation. The listed outcome answers a descriptive safety question, not an imaging-accuracy or comparative-effectiveness question.

The single-group design also sets a clear boundary on inference. The registry reports one MRI group and no randomized comparator. As a result, counts from this cohort can describe recorded events but cannot isolate what would have happened under another planning approach. This is a basic design issue, not a flaw that can be resolved by a statistical test after the fact.

The posted zero counts are easy to state, but their interpretation requires attention to denominators, follow-up, and uncertainty. The record lists 15 participants at risk in each safety category, yet does not report follow-up completeness, an uncertainty interval, or a detailed event definition. These missing details make it important to distinguish the observed record from a claim about risk in a wider population.

Finally, the absence of reported analyses is itself relevant. Without a reported analysis plan, hypothesis test, or estimate with uncertainty, readers should not infer that a statistical comparison was performed. Planning illustrations based on hypothetical two-arm assumptions do not replace an analysis of the single-group data and are not observed power. This record therefore illustrates how design, endpoint selection, and reporting detail determine the scope of statistical interpretation.

15. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The principal limitation for interpretation is the single-group design. The registry explicitly identifies no randomized comparison and no separate control arm. Consequently, the results cannot estimate a difference between functional MRI and another imaging or planning approach, nor can they attribute the recorded safety counts to the intervention.

Enrollment is listed as 15. For a descriptive safety outcome, this is the size of the group represented in the record, but the registry does not report an uncertainty interval or analysis that would quantify precision. A count of 0 affected participants should not be interpreted as proof of no risk. The record also does not say whether all participants completed the stated 2-year timeframe.

The primary endpoint is a count of participants with adverse events. The registry does not provide a detailed event definition, event descriptions, dates, assessment procedures, or a fuller account of how serious and other events were classified. It is therefore not possible from the record to assess the nature of events or the completeness of event ascertainment.

The study's stated purpose concerns MRI identification of intraprostatic tumor, but the registry lists adverse events as its primary outcome and reports no analysis of imaging accuracy, treatment-plan changes, or clinical outcomes. Those questions remain outside the reported results. The registry also does not report statistical methods, analysis populations, missing-data handling, multiplicity plans, or the trial's own sample-size justification.

The brief summary describes a projected study duration of 18 months, while the primary outcome timeframe is 2 years. The registry does not explain the relationship between that projection and participant-level follow-up. The record lists a completed status but does not provide further detail on completion of individual follow-up or procedures.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Functional MRI Use in Prostate Radiation Treatment Planning — NCT01985932.
• Registry record last updated 2019-11-26; status last verified 2019-11.
• Results first posted 2019-11-26.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

19. Record Summary

The registry record describes a completed, prospective, single-group study of functional MRI during prostate radiation treatment planning. Its official title focuses on non-endorectal coil functional MRI identification of intraprostatic tumor. The sponsor is Abramson Cancer Center at Penn Medicine, and the listed condition is prostate cancer.

Enrollment is 15. The summary describes male adults aged 18 or older with prostate cancer and treatment plans at the Department of Radiation Oncology. The primary outcome is the number of participants with adverse events over 2 years. The Functional MRI group lists 15 participants at risk and 0 affected for serious adverse events, and 15 at risk and 0 affected for other adverse events.

The study is not a randomized comparison, and the registry lists no analyses. It does not report an inferential analysis, comparator group, imaging-accuracy result, missing-data approach, or analysis population. The posted results therefore support a descriptive reading of the safety counts, not a comparative or diagnostic-performance conclusion.