BMT4me: Post-HSCT Medication Adherence mHealth App: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for BMT4me: Post-HSCT Medication Adherence mHealth App (NCT05515497), a randomized na study. The primary outcome is Momentary Event Monitoring System (MEMS) Caps.

2. Clinical Question

This is a pilot randomized controlled trial (RCT), not a registry record of a definitive efficacy analysis. Its stated aims include acceptability and feasibility as well as potential efficacy. These aims matter when reading the results: the study description does not frame medication adherence as the only question, and the available primary outcome figures do not establish a precise app-versus-usual-care estimate.

The trial concerns a specific care context: pediatric patients after HSCT and immunosuppressant adherence during the acute period after discharge. The registry record does not report further eligibility details or define the population beyond its study description. The primary outcome timeframe is baseline to day 100. The secondary outcomes include a medication-level variability measure, graft-versus-host disease (GVHD), readmissions, caregiver education level, and annual household income.

The central statistical question is whether the recorded adherence data support a reliable comparison between randomized groups. The posted MEMS Caps summaries are based on only 3 intervention participants and 6 control participants. The registry also states that only a subset received this version of electronic monitor and that monitor type depended on participant preference. Those features restrict what can be inferred from the primary outcome values. The registry record does not report a sponsor-conducted statistical comparison for that endpoint.

3. Trial Design

The registry identifies NCT05515497 as BMT4me: Post-HSCT Medication Adherence mHealth App, with the official title BMT4me: Improving Adherence Through mHealth for Pediatric Stem Cell Transplant Patients (BMT4me 2.0). It describes a mixed-methods, prospective longitudinal pilot RCT. The recorded allocation is randomized, the masking is none, and the model is parallel. The phase is listed as NA. The enrollment is 50, and the trial status is completed.

The intervention arm received the BMT4me 2.0 app at discharge. The control arm received usual care at discharge and did not receive the app. The trial description says it aims to evaluate the app’s acceptability, the feasibility of enrolling and retaining caregivers of children in the acute phase after HSCT, and the app’s potential effect on adherence to immunosuppressants after discharge.

The recorded start date is 2022-11-29, and the primary completion date is 2026-01-02. The primary outcome is MEMS Caps adherence percentage from baseline to day 100. Other posted outcomes include Medication Level Variability Index (MLVI), participants with GVHD, and participants with readmissions. Caregiver education level and annual household income are also listed as secondary outcomes, but results for those measures are not included in the posted secondary results described in the registry record.

The MEMS Caps primary outcome is explicitly limited to a subset: the registry says only a subset of the total study population received this version of an electronic monitor and that monitor type depended on participant preference. The primary summaries include 3 intervention participants and 6 control participants. These outcome-specific counts should not be treated as the number randomized or as a description of the full study population. The registry records 24 and 26 participants at risk for adverse-event reporting in the intervention and control groups, respectively, but it does not explain the differences between those safety counts and the primary-outcome counts.

The record lists 14 outcome measures, while 5 secondary outcomes are posted in the results represented. It reports no analyses for the primary endpoint and no reported analyses for the posted secondary endpoints. Details of the randomization procedure, allocation concealment, statistical analysis plan, and any interim analyses 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.

Before assignment: Caregivers were randomized to the intervention (m-Health app) or control group (standard of care) via sequencing in REDCap maintained by a statistician. Some adolescents self-identified as the person responsible for medication management and were enrolled as caregiver.

Overall Study

Analysis population for the primary outcome, as defined in the registry: Only a subset of the total study population received this version of an electronic monitor. Type of monitor depended on participant preference.

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 Momentary Event Monitoring System (MEMS) Caps, measured over Baseline to day 100.

The primary endpoint is mean adherence percentage measured with Momentary Event Monitoring System (MEMS) Caps from baseline to day 100. These electronic caps record the date and time when a medication container is opened. The registry’s measurement description treats each opening and closing as reflecting an administered and consumed dose. It describes adherence percentage as the number of doses taken divided by the number prescribed for each day, with data collected weekly or monthly at visits in the BMT clinic.

Electronic monitoring is used because it can record medication-container openings over time rather than relying solely on a participant’s or caregiver’s recollection. This is a general measurement advantage: a time-stamped record can capture patterns in container use. It is not a direct confirmation that a dose was swallowed. An opening is an observable event, while ingestion is the behavior the study ultimately seeks to assess. The registry’s interpretation therefore rests on an explicit assumption linking openings to doses administered and consumed.

The measure is reported as a mean with standard deviation. In the intervention group, the posted mean is 62.78 percent with standard deviation 22.14, based on 3 participants. In the control group, the mean is 61.06 percent with standard deviation 32.92, based on 6 participants. These are descriptive summaries, not a reported treatment-effect estimate. The registry does not post a confidence interval, p-value, or sponsor-reported between-group analysis for this primary endpoint.

Interpretation is further limited because only a subset received this version of the electronic monitor, and the registry says monitor type depended on participant preference. The registry record does not report how many participants used other monitor types, how the subset was selected, or whether the MEMS Caps results were intended to represent the full randomized population.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes randomized allocation to parallel groups, but it does not report the randomization method, allocation concealment, or statistical analysis plan. Randomization is generally intended to make comparison groups similar in expectation, including with respect to measured and unmeasured characteristics. In a small trial, however, chance imbalance can remain, and a subset measured with a particular monitor may not preserve the balance achieved by randomization. These are general considerations; the registry record does not report whether such imbalances occurred in this trial.

What do the group summaries describe?

For continuous outcomes, a mean is the arithmetic average of the observations included in that group’s summary. The standard deviation describes how dispersed individual observations are around that mean. It is not the uncertainty interval for the mean and does not directly give the uncertainty in a between-group contrast. The primary endpoint reports a mean and standard deviation for each group, but the registry does not report a primary contrast or its uncertainty. The MEMS Caps summaries also use only the subset with that monitor, rather than a reported analysis of all randomized participants.

For the continuous secondary outcome MLVI, the posted group means and standard deviations allow a simple unadjusted comparison to be recalculated. The resulting mean difference is 0.28, with a 95% confidence interval from -1.143 to 1.703 and p = 0.7. This is not an adjusted model estimate or a sponsor-reported result. The calculation uses the posted summary statistics and does not account for covariates, repeated measurements, or any other analysis features not described in the record.

How should a confidence interval be read?

A confidence interval describes the range of values reasonably compatible with the data and the method used to calculate it. In general, a wide interval indicates substantial uncertainty about the size and direction of an effect. An interval that includes no difference does not establish that there is no effect; it indicates that the data and method do not distinguish the estimate from no difference at the stated confidence level. For MLVI and the two posted binary comparisons, the intervals include no difference and span values on both sides of it. Their breadth is consistent with limited precision.

The binary secondary outcomes are reported as counts of participants with an event. A risk difference expresses the difference between the observed group proportions, with the intervention group compared against the control group in the recalculated summaries. For GVHD, the recalculated unadjusted risk difference is 0.095; its 95% confidence interval is -0.167 to 0.357. For readmissions, the recalculated unadjusted risk difference is -0.065; its 95% confidence interval is -0.340 to 0.209. These intervals allow effects in either direction. The accompanying unadjusted p-values are 0.478 and 0.644, respectively. A p-value measures how incompatible the data are with a specified null model under the method’s assumptions; it is not the probability that the null hypothesis is true or a measure of clinical importance.

Why can over-dispersion matter?

For count or rate outcomes, over-dispersion means the observed variability is greater than a chosen statistical model expects. If a model assumes less variability than the data contain, standard errors can be too small and intervals or tests can appear more decisive than they should. This is a general issue in modeling counts and rates. The posted outcomes are group-level participant counts and continuous summaries, and the registry record does not report a count-rate model or an assessment of over-dispersion. No conclusion about over-dispersion in this trial can be drawn from the record.

Repeated or longitudinal observations also require care. The study is described as prospective and longitudinal, and some outcomes are assessed weekly until day 100. Measurements from the same participant over time are generally correlated rather than independent. Statistical methods for repeated measurements account for that correlation when appropriate. The registry does not report whether the sponsor used a longitudinal model, how repeated values were handled, or whether the posted group summaries represent a particular visit, an average over visits, or another summary beyond the stated outcome definitions. The simple recalculations therefore should not be mistaken for longitudinal analyses.

What do the planning illustrations mean?

The registry’s planning illustrations use the observed effect as a reference and show hypothetical participants per arm for 80% and 90% power when targeting 100%, 75%, or 50% of that effect. Their stated assumptions are a two-sided significance level of 0.05, equal allocation, and a normal approximation. For MLVI, the illustrations are 958 and 1,282 participants per arm for 80% and 90% power when planning for 100% of the observed effect; 1,702 and 2,279 when planning for 75%; and 3,830 and 5,127 when planning for 50%. For GVHD, the corresponding figures are 382 and 511, 667 and 893, and 1,471 and 1,968. For readmissions, they are 896 and 1,199, 1,604 and 2,146, and 3,628 and 4,857.

These are planning illustrations calculated from observed effects, not the trial’s original sample-size justification. The registry record does not report the study’s own design assumptions or sample-size justification. Such calculations are particularly sensitive to the observed effect in a small pilot, which may be imprecise. They are not observed power, do not show that the trial had a particular probability of detecting an effect, and cannot substitute for a prespecified design calculation based on a justified target effect.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("BMT4me 2.0 Intervention Group", "BMT4me 2.0 Control Group")
n   <- c(3, 6)
m   <- c(62.78, 61.06)
sp  <- c(22.14, 32.92)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  BMT4me 2.0 Intervention Group  3  62.780  22.140  7.781  117.779
CARM  BMT4me 2.0 Control Group  6  61.060  32.920  26.513  95.607

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 14 outcome measures and reports 5 posted secondary outcomes. It does not state which outcomes were prespecified as key secondary endpoints, whether a hierarchy was planned, or whether a multiplicity correction was used. When many outcomes are assessed, the chance of observing an apparently unusual result among them can increase. This is a general statistical concern, not a claim that any specific posted result is a false positive. Without a reported multiplicity plan, secondary p-values should be treated as exploratory and interpreted with the estimates and confidence intervals rather than as independent confirmatory tests.

The record reports no sponsor analyses for the primary endpoint and no reported analyses for the posted secondary endpoints. The primary MEMS Caps outcome is flagged as lacking values or being not estimable for a two-arm comparison. The registry does not report why a comparison was unavailable, whether data were missing, whether the endpoint was not analyzed, or how these possibilities were distinguished. It also does not report a missing-data strategy, sensitivity analyses, or imputation methods. Reasons for missingness and the likely relation of missingness to outcomes cannot be inferred from the posted record.

Analysis populations are not described in sufficient detail to establish whether results use an intention-to-treat population, a per-protocol population, or another defined set. The record gives an enrollment of 50, but the primary MEMS Caps summaries use 3 intervention participants and 6 control participants. The registry says only a subset received this monitor version and that monitor type depended on participant preference; it does not explain how the subset relates to the full randomized population. Secondary outcome denominators also differ by outcome, and the registry does not explain all denominator differences. These counts should be read as outcome-specific rather than assumed to represent one common analysis population.

The registry does not report interim analyses, stopping rules, a formal statistical analysis plan, or methods for handling repeated observations. Those details are important for evaluating selective reporting, the interpretation of longitudinal measurements, and the scope of the reported tests. Their absence from the record does not establish that a particular method was or was not used; it means the relevant information is not reported in the registry record.

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.

For serious adverse events, the registry records 0 affected participants among 24 at risk in the BMT4me 2.0 intervention group and 0 among 26 at risk in the control group. It also records 0 deaths in each group. For other adverse events, it records 0 affected participants among 24 at risk in the intervention group and 0 among 26 at risk in the control group. No serious-event terms are listed.

These figures describe what is recorded for the specified groups and reporting period; they do not establish that the risk of an adverse event is zero. In general, observing no events does not rule out events that were not captured, events outside the reporting window, or uncommon events that could occur in a larger population. The registry record does not provide further detail about adverse-event definitions, collection procedures, severity grading, relatedness assessment, or the reporting timeframe. The figures should therefore be read as registry safety counts, not as proof of the absence of risk or as a comparison demonstrating equal safety between groups.

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

The posted results describe a completed randomized pilot trial of BMT4me 2.0 versus usual care after pediatric HSCT. They show descriptive MEMS Caps adherence means for a subset and provide secondary outcome summaries. They do not include a sponsor-reported statistical comparison for the primary endpoint. The primary data therefore do not provide a registry-reported estimate of the app’s effect on adherence, with a confidence interval that would describe its precision.

The secondary comparisons are recalculated, unadjusted estimates from posted summary statistics. Their confidence intervals include no difference and span values in either direction. This means the results are uncertain; it does not demonstrate that the app and usual care are equivalent, nor does it establish that either approach is superior. A nonsignificant p-value is not evidence that a meaningful effect has been ruled out, especially when estimates are imprecise and the analysis is not reported by the sponsor.

The primary monitor measure has additional limits. It captures container openings, which the registry assumes reflect doses administered and consumed, but an electronic opening is not direct confirmation of ingestion. Only a subset received this version of the monitor, and monitor choice depended on participant preference. These circumstances constrain generalization from the posted summaries to the full randomized trial population. The registry does not report how the subset was selected or how results from other monitor types were incorporated.

The trial description identifies acceptability and caregiver recruitment and retention as aims, in addition to potential efficacy. However, the record does not provide results for all of those aims in the outcome summaries described. A pilot trial can help identify practical and measurement issues and inform future study planning, but the posted results do not settle whether the app changes adherence or other outcomes. Nor do the planning illustrations establish observed power or validate a future sample-size target; they are calculations based on observed effects under stated assumptions.

Overall, the registry record supports a cautious descriptive reading. It documents group summaries and the absence of recorded adverse events in the listed safety counts, but it does not provide the analyses, missing-data information, or detailed methods needed for firm comparative conclusions. No treatment recommendation follows from these registry results.

14. Why This Trial Matters Statistically

This trial raises a central statistical issue in digital-health research: the outcome used to evaluate an intervention may be observed for only part of the randomized population. Here, the primary adherence measure comes from MEMS Caps, but the registry says only a subset received this monitor and that monitor type depended on participant preference. Statistical interpretation depends not only on the outcome’s definition but also on who contributed data and how measurement differences across participants were handled. Those details are not reported in the registry record.

The distinction between a promising measurement strategy and a precise treatment comparison is also important. Electronic monitoring can produce time-stamped records of container openings, but the registry’s endpoint summaries alone do not establish how reliably those openings represent ingested doses. Nor do the small outcome-specific counts yield a reported, precise comparison between randomized groups. A pilot can expose such issues and provide descriptive information, while still leaving the efficacy question unresolved.

The record also illustrates why confidence intervals and analysis transparency matter. Secondary estimates are available as simple unadjusted recalculations, but their intervals permit differences in both directions. The registry lists multiple outcomes and does not report a multiplicity plan, missing-data methods, analysis populations, or a sponsor statistical analysis for the posted outcomes. Without these elements, isolated results should not be elevated into definitive evidence.

Finally, sample-size planning based on observed pilot effects can be unstable. The registry’s planning illustrations show how hypothetical requirements change when the target effect is a stated fraction of the observed effect. They do not reflect the trial’s original design justification, which is not reported, and they are not observed power. This distinction helps prevent a small exploratory study from being judged by an inappropriate post hoc power calculation. The statistical value of the record lies in clarifying what is measured, which data are available, and what remains uncertain.

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 most important trial-specific limitation in the posted primary result is that MEMS Caps data come from only a subset, with 3 intervention participants and 6 control participants. The registry states that only a subset of the total study population received this monitor version and that monitor type depended on participant preference. The record does not report how participants came to use this monitor, whether the choice was related to adherence or other characteristics, or how the other monitor types contributed to the primary assessment. This limits both precision and confidence that the subset represents the randomized groups.

The primary outcome is an indirect measure of medication-taking behavior. The registry treats container openings as doses administered and consumed, but opening does not directly verify ingestion. The record describes weekly or monthly data collection at clinic visits and software downloads, yet it does not explain how adherence was summarized across visits, how missed or invalid monitor readings were handled, or whether monitor use itself altered behavior. These details are not reported in the registry record.

The registry provides no sponsor-reported primary comparison and flags the endpoint as missing or not estimable for a two-arm comparison. It does not clarify whether this reflects missing observations, an analysis decision, or another issue. There is also no reported statistical analysis plan, analysis population definition, missing-data method, multiplicity approach, or account of repeated-measure modeling. Secondary results likewise have outcome-specific denominators, and the reasons for those differences are not fully reported.

Although the study is randomized, the record does not describe the randomization procedure or allocation concealment. The trial is unmasked. The registry also lists caregiver feasibility and app acceptability as aims, but those results are not included among the posted outcome summaries. These reporting gaps make it difficult to assess recruitment and retention, representativeness, and the completeness of outcome reporting. They should be treated as limits of what can be concluded from the registry record, not as evidence that particular procedures were absent.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: BMT4me: Post-HSCT Medication Adherence mHealth App — NCT05515497.
• Registry record last updated 2026-10-27; status last verified 2026-10.
• Results first posted 2026-10-27.
• 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

NCT05515497 is a completed, randomized, unmasked, parallel-group pilot RCT of BMT4me 2.0 versus usual care at discharge for pediatric patients after HSCT. The recorded enrollment is 50. The trial description focuses on app acceptability, caregiver recruitment and retention feasibility, and potential effects on immunosuppressant adherence.

The primary outcome is mean MEMS Caps adherence percentage from baseline to day 100. Posted summaries cover 3 intervention participants and 6 control participants; the registry notes that only a subset received this monitor version and that monitor type depended on participant preference. No primary two-arm analysis is reported. Posted secondary results include MLVI, GVHD, and readmissions, with unadjusted recalculations that remain imprecise. The registry does not report a statistical analysis plan, missing-data methods, analysis populations, or a multiplicity strategy. Safety counts record no serious or other adverse events and no deaths in the listed groups.