Learning to Apply Mindfulness to Pain: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Learning to Apply Mindfulness to Pain (NCT04526158), a randomized na study. The primary outcome is Change in the Brief Pain Inventory (BPI) Interference Score From Baseline, Over the 12-month Follow-up Period..

2. Clinical Question

3. Trial Design

The registry describes a randomized, open-label, parallel-group trial and lists the status as completed. The study title identifies it as a pragmatic, multisite trial, but the number of sites is not reported in the registry record. Enrollment was 811. The record lists the United States Department of Defense as sponsor, gives a start date of 2020-11-02, and gives a primary completion date of 2023-08-30.

Participants were assigned to Mobile+Group LAMP, Mobile LAMP, or Usual Care. The group-based program included 8 weekly synchronous online sessions, app and website access, and a workbook. The mobile-only program included 8 weekly asynchronous sessions delivered through an app and website, a workbook, and 3 engagement calls. Usual Care involved participants continuing their usual care for 12 months; access to Mobile LAMP materials was offered after follow-up ended.

Masking is listed as none. Participants would therefore know which program they received, and the registry does not describe blinded outcome assessment. The primary outcome was a continuous BPI Interference Score, analyzed as a weighted average across follow-up time points with adjustment for baseline. The posted arm counts for that outcome are 270, 271, and 270, respectively. They describe participants represented in the outcome results; the registry does not explain how those counts relate to the full enrollment or whether all randomized participants were included in each analysis.

Details of the original sample-size justification, allocation procedures, stratification, trial protocol, and analysis populations are not reported in the registry record. Those omissions limit reconstruction of the design and the planned statistical analysis from the registry entry alone.

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 Change in the Brief Pain Inventory (BPI) Interference Score From Baseline, Over the 12-month Follow-up Period., measured over Weighted average over 10 weeks, 6 months, and 12 months..

The primary endpoint is change in the Brief Pain Inventory (BPI) Interference Score from baseline over the 12-month follow-up period. The BPI interference measure captures the effect of pain on functioning. The registry states that the scale ranges from 0 to 10, with higher scores indicating worse functioning. The reported outcome is operationalized as a weighted average across the follow-up time points, adjusting for the baseline value before randomization. The specified time points are 10 weeks, 6 months, and 12 months.

A continuous score retains more information about the degree of reported interference than a simple classification such as improved or not improved. Comparing average scores can therefore describe the direction and size of group differences on the measured scale. Baseline adjustment accounts statistically for the starting score, while a weighted average combines information across the specified follow-up period rather than treating one time point as the sole outcome.

These features do not by themselves establish that a difference is important to participants. The registry record does not give a threshold for a clinically meaningful change or explain how the weights for the follow-up time points were selected. The score is a participant-reported measure, and the open-label design may matter when considering responses to questionnaires. The endpoint measures reported pain interference; it is not a direct measure of pain intensity, and the trial reports pain intensity separately as a secondary outcome.

7. Results Posted in the Registry

• Mobile+Group LAMP Mindfulness-Based Intervention: mean 4.80 versus 5.20 on control; difference -0.40 (95% CI -0.68 to -0.12), standardized effect d = -0.24; z-test p = 0.005.
• Mobile LAMP Mindfulness-Based Intervention: mean 4.50 versus 5.20 on control; difference -0.70 (95% CI -0.98 to -0.42), standardized effect d = -0.43; z-test p = <0.001.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Change in the Brief Pain Inventory (BPI) Intensity Score From Baseline, Over the 12-month Follow-up Period.

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • Mobile+Group LAMP Mindfulness-Based Intervention: mean 4.70 versus 5.10 on control; difference -0.40 (95% CI -0.68 to -0.12), standardized effect d = -0.24; z-test p = 0.005.
  • Mobile LAMP Mindfulness-Based Intervention: mean 4.60 versus 5.10 on control; difference -0.50 (95% CI -0.78 to -0.22), standardized effect d = -0.30; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Mobile+Group LAMP Mindfulness-Based Intervention than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Mobile LAMP Mindfulness-Based Intervention than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Change in Physical Functioning Over the 12-month Follow-up Period Assessed by Mean Score on the Patient-Reported Outcomes Measurement Information System (PROMIS)-29 Profile v.2.0 Measure of Physical Function

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • Mobile+Group LAMP Mindfulness-Based Intervention: mean 13.30 versus 12.70 on control; difference 0.60 (95% CI 0.32 to 0.88), standardized effect d = 0.37; z-test p = <0.001.
  • Mobile LAMP Mindfulness-Based Intervention: mean 13.30 versus 12.70 on control; difference 0.60 (95% CI 0.32 to 0.88), standardized effect d = 0.36; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically higher for Mobile+Group LAMP Mindfulness-Based Intervention than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
  • The 95% confidence interval excludes no difference, so the mean is statistically higher for Mobile LAMP Mindfulness-Based Intervention than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Change in Anxiety Over the 12-month Follow-up Period Assessed by Mean Score on the Patient-Reported Outcomes Measurement Information System (PROMIS)-29 Profile v.2.0 Measure of Anxiety

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • Mobile+Group LAMP Mindfulness-Based Intervention: mean 9.20 versus 9.40 on control; difference -0.20 (95% CI -0.48 to 0.08), standardized effect d = -0.12; z-test p = 0.157.
  • Mobile LAMP Mindfulness-Based Intervention: mean 8.80 versus 9.40 on control; difference -0.60 (95% CI -1.04 to -0.16), standardized effect d = -0.23; z-test p = 0.007.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Mobile+Group LAMP Mindfulness-Based Intervention and the control. The interval gives the range of effects that remain compatible with the data.
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Mobile LAMP Mindfulness-Based Intervention than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The secondary outcomes extend the assessment beyond pain interference to pain intensity, physical functioning, anxiety, fatigue, sleep disturbance, social participation, depression, and PTSD. Across the secondary results described in the registry record, the numerical pattern is not uniform across measures or intervention comparisons. The posted intensity and physical-function summaries generally point in a favorable direction for the intervention arms relative to usual care, while the anxiety findings are less consistent across the two programs. This provides context for the primary result without making the secondary measures equivalent to it.

Some secondary outcomes are conceptually close to pain interference, while others assess different aspects of wellbeing or daily functioning. Agreement across related measures may help readers understand whether the primary pattern extends to other domains, but a difference on one scale does not imply a difference on another. Each outcome has its own measurement properties and interpretation. The registry lists 10 secondary outcomes, but detailed results are not reported for every listed measure in the record summarized by these results.

Secondary findings generally carry less confirmatory weight when many outcomes and contrasts are examined. Each additional statistical test creates another opportunity for a nominally notable result to arise by chance. The registry record does not report a multiplicity adjustment, a prespecified hierarchy for secondary outcomes, or a procedure for distinguishing confirmatory from exploratory analyses. Unadjusted secondary p-values should therefore be interpreted cautiously and in the context of the whole outcome set, not as independent proof of benefit.

The secondary data can suggest questions for further study, such as whether effects are consistent across related measures and follow-up time points. They do not replace the designated primary endpoint, and they cannot establish how meaningful a score difference is without a relevant interpretive threshold. The registry record does not report such thresholds for these secondary measures.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Change in the Brief Pain Inventory (BPI) Intensity Score From Baseline, Over the 12-month Follow-up Period.
• Change in Physical Functioning Over the 12-month Follow-up Period Assessed by Mean Score on the Patient-Reported Outcomes Measurement Information System (PROMIS)-29 Profile v.2.0 Measure of Physical Function
• Change in Anxiety Over the 12-month Follow-up Period Assessed by Mean Score on the Patient-Reported Outcomes Measurement Information System (PROMIS)-29 Profile v.2.0 Measure of Anxiety
• Change in Fatigue Over the 12-month Follow-up Period Assessed by Mean Score on the Patient-Reported Outcomes Measurement Information System (PROMIS)-29 Profile v.2.0 Measure of Fatigue
• Change in Sleep Disturbance Over the 12-month Follow-up Period Assessed by Mean Score on the Patient-Reported Outcomes Measurement Information System (PROMIS)-29 Profile v.2.0 Measure of Sleep Disturbance
• Change in Participation in Social Roles and Activities Over the 12-month Follow-up Period Assessed by Mean Score on the PROMIS-29 Profile v.2.0 Measure of Participation in Social Roles and Activities
• Change in Depression Over the 12-month Follow-up Period Assessed by Score on the Eight-item Patient Health Questionnaire Depression Scale (PHQ8)
• Change in Post Traumatic Stress Disorder (PTSD), Over the 12-month Follow-up Period, Assessed by Participants' Scores on the Post Traumatic Stress Disorder Checklist for Diagnostic and Statistical Manual of Mental Disorders - 5 (PCL-5)

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is continuous, so the registry reports mean scores and mean differences. A mean is a group average. A mean difference expresses the contrast between two group estimates on the outcome’s scale. Its sign depends on which group is subtracted from which; in this trial, a lower BPI Interference Score indicates less reported interference because higher scores indicate worse functioning. The registry’s reported model-based comparison and a direct subtraction of posted arm summaries can use different estimands, even when both concern the same outcome.

What does baseline adjustment do?

Baseline adjustment incorporates the pre-randomization value into the analysis of follow-up results. In general, this can account for chance differences in starting scores and may improve precision when baseline and follow-up measurements are related. The registry says the primary outcome was adjusted for the baseline value. The exact model specification, covariance structure, and handling of repeated measurements are not reported in the registry record, so the model cannot be reproduced from the posted description alone.

Why use a weighted average over follow-up?

The primary endpoint combines measurements from 10 weeks, 6 months, and 12 months into a weighted average. In general, a weighted average allows some measurements to contribute differently from others, according to the chosen weights. It can summarize the course over follow-up rather than emphasizing a single time point. The registry does not state the numerical weights or give a rationale for them. The average therefore should be interpreted as the particular summary defined by the trial, not as a simple unweighted average or as a result at the final visit alone.

What is the role of the confidence interval?

A confidence interval describes the precision of an estimate under the statistical model and its assumptions. In general, a narrower interval indicates greater precision, while a wider interval leaves more uncertainty about the range of values compatible with the data and model. The sponsor’s reported analyses use 95% confidence intervals. For example, the registry reports intervals for intervention-versus-usual-care differences that remain below zero. That pattern is consistent with the direction of the estimated differences, but it does not reveal the probability that a particular treatment effect is true.

What does a p-value tell readers?

A p-value measures how unusual the observed data, or more extreme data, would be under a specified null hypothesis and statistical model. It is not the probability that the null hypothesis is true, and it does not measure the size or importance of an effect. The registry reports p-values for its mixed-model contrasts; the recalculated comparisons use unadjusted p-values derived from posted summary statistics. These p-values belong to different analyses and should not be treated as interchangeable. A small p-value can coexist with uncertainty about clinical importance, generalizability, or the validity of model assumptions.

Why can unadjusted re-calculations differ?

The unadjusted re-calculations use the posted arm summaries to estimate simple group differences. They do not reproduce the trial’s mixed-model analysis. A model can account for baseline values and repeated follow-up data in ways not captured by a direct comparison of arm-level summaries. The registry’s reported analyses are therefore the appropriate reference for what the trial’s own model found. The record does not specify enough detail to independently verify every modeling choice or to reconstruct the reported estimates.

What do the secondary analyses add?

Secondary outcomes measure other aspects of pain and functioning, including pain intensity, physical function, anxiety, fatigue, sleep disturbance, social participation, depression, and PTSD. Such measures can broaden the picture of observed outcomes, but they are not interchangeable with the primary pain-interference endpoint. In general, multiple outcomes and comparisons create more opportunities for chance findings. The registry does not report a multiplicity adjustment or a hierarchy for interpreting secondary outcomes. Their p-values should therefore be read as exploratory evidence unless a prespecified testing strategy is documented.

What is not established by the methods record?

The original sample-size rationale, planned analysis populations, missing-data procedures, protocol deviations, interim analyses, and detailed statistical analysis plan are not reported in the registry record. These details matter because missing observations, exclusions, or changes from the original plan can affect both estimates and uncertainty. Their absence does not demonstrate that the trial lacked such procedures; it means the registry record does not document them. Statistical interpretation should remain tied to the analyses and information that are actually reported.

11. Confidence Intervals and Precision

The registry’s primary mixed-model estimates for intervention versus usual care have 95% confidence intervals. For Mobile+Group LAMP, the reported mean difference is -0.4, with an interval from -0.7 to -0.2. For Mobile LAMP, the reported mean difference is -0.7, with an interval from -1.0 to -0.4. Both intervals lie on the negative side of zero under the registry’s reported contrast ordering. The Mobile+Group LAMP versus Mobile LAMP interval runs from 0.0 to 0.6, with a reported estimate of 0.3.

A confidence interval is a measure of precision, not a range containing a known fixed proportion of individual participant outcomes. In general, an interval describes values compatible with the observed data under the specified model and repeated-sampling framework. The interval does not incorporate every source of uncertainty, such as uncertainty about outcome measurement, missing-data assumptions, or whether the model was appropriate.

The endpoint is measured on a scale from 0 to 10, and higher scores indicate worse functioning. That scale helps describe the meaning of the direction, but the record does not state what size of score difference participants would consider important. Thus, the intervals can inform how precisely the statistical contrasts were estimated, but cannot by themselves establish clinical importance.

The recalculated intervals are based on posted summary statistics and an unadjusted approach. The registry’s model-based intervals reflect the reported mixed-model analyses and are the more relevant intervals for describing the sponsor’s analysis. Differences in methods and rounding mean that estimates should be interpreted alongside their analysis definitions, rather than compared as though they were identical calculations.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The sample-size figures are planning illustrations based on the observed effect, not the trial’s original design justification. For these continuous outcomes, the figures refer to participants per arm, not total events. The planning assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The assumed effect to detect is the stated fraction of the observed effect. The trial’s own original sample-size assumptions are not reported in the registry record.

The 80% power column gives the estimated participants per arm for a future study to have an 80% chance of detecting the assumed effect under those planning assumptions, if that effect is the true effect and the model assumptions hold. The 90% power column uses a higher target chance of detection and therefore generally requires more participants per arm. These are design calculations, not claims about how likely this completed trial was to detect an effect after the fact. This is not observed power.

Rows planning for 100%, 75%, or 50% of the observed effect illustrate how the assumed effect size changes the required sample. Smaller effects require more participants because they are harder to distinguish from random variation. The effect used for planning is based on the observed trial estimate, which can itself be uncertain, so these figures should be treated as illustrations rather than guarantees about a future study. They also do not account for features not listed in the assumptions, such as loss to follow-up or a more complex allocation design.

The curve presents the same general planning relationship visually: larger target effects require fewer participants than smaller target effects under the stated assumptions. It should not be interpreted as a reconstruction of the trial’s design process. The registry record does not report whether these specific calculations informed the original enrollment target.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = -0.400; pooled standard deviation σ = 1.643.
2. n = 2 × (1.96 + 0.842)² × 1.643² / -0.400² = 264.9, rounded up to 265 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- -0.4                      # observed difference in means
sigma <- 1.6431676725155                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(4526158)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 265 (80% power), 355 (90% power)
 75% of observed effect: n per arm = 471 (80% power), 631 (90% power)
 50% of observed effect: n per arm = 1,060 (80% power), 1,419 (90% power)
power.t.test: 265.9 
Simulated power at n = 265 per arm: 0.801 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Analyses Reported by the Sponsor

The registry reports the trial’s own primary analyses as mixed models of mean differences in final values. Those analyses give intervention-versus-usual-care estimates of -0.4 for Mobile+Group LAMP and -0.7 for Mobile LAMP, with reported p-values of 0.002 and <0.001. The reported comparison between the two intervention arms is 0.3, with p = 0.031. Each estimate should be read with its stated group ordering and confidence interval.

The recalculated values use unadjusted comparisons of posted summary statistics. They are a check on the broad direction and approximate magnitude of the arm-level contrasts, not a replication of the mixed model. The primary arm summaries are 4.8, 4.5, and 5.2 for Mobile+Group LAMP, Mobile LAMP, and Usual Care, respectively. Their simple contrasts with usual care point in the same general direction as the model-based intervention-versus-usual-care results. The model-based estimates and their p-values remain the appropriate description of the trial’s reported analysis.

The registry does not flag a discrepancy between its posted result and the recalculation. Even so, rounded arm summaries cannot reconstruct a baseline-adjusted repeated-measures model, and the comparison between intervention arms illustrates why contrast definitions matter. The registry’s result labels the model parameter as a mean difference in final values, whereas the recalculation uses weighted-average outcome summaries. The two procedures should not be conflated.

15. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when an analysis tests multiple outcomes, time points, or group contrasts. Even when every null hypothesis is true, a larger set of tests increases the chance that at least one result will appear statistically notable by chance. This is a general statistical issue, not evidence that any particular reported result is false. The trial lists a primary endpoint and multiple secondary endpoints, and reports numerous analyses. The registry record does not report a multiplicity adjustment, a testing hierarchy, or which secondary comparisons were intended to be confirmatory.

Consequently, the primary endpoint has a clearer designated role than the secondary findings, while unadjusted secondary p-values should be treated as less conclusive. The registry’s labels of superiority describe the type of comparison reported; they do not establish that family-wise error across all outcomes was controlled. The original protocol and detailed statistical analysis plan are not reported in the registry record, so it is not possible to determine from this entry whether another multiplicity strategy was prespecified.

Missing data can also affect estimates. Repeated outcomes over follow-up may be unavailable for some participants, and the way an analysis handles missing measurements can influence results. The registry record gives outcome arm counts but does not report the amount or pattern of missingness, the reasons for missing data, or the assumptions and procedures used to address it. It therefore does not support conclusions about whether missingness was balanced across groups or whether the primary model’s missing-data assumptions were plausible.

The analysis population is also not described in sufficient detail. The registry does not state whether the primary analysis included all randomized participants, a subset with available outcomes, or another defined group. It does not report how nonadherence, crossover, or protocol deviations were handled. These are reporting gaps, not evidence that a particular analytic choice was made. Without these details, readers cannot fully assess how closely the reported estimates preserve the randomized comparison or reproduce the intended analysis.

16. 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 registry reports zero serious adverse events among the 270 participants listed as at risk in Mobile+Group LAMP, the 271 listed in Mobile LAMP, and the 270 listed in Usual Care. It also reports zero other adverse events and zero deaths in each arm. The record lists no serious adverse-event terms. These are the posted event counts for the groups and at-risk counts reported in the registry.

A count of zero means that no event in the specified category was reported for the listed group in this record. It does not prove that an intervention has no risks, and it does not rule out events that were not captured, reported, or categorized in the registry. The record does not provide additional detail about event definitions, the observation window for each safety category, or the process used to collect adverse-event information. The figures should therefore be read as registry reporting, not as a comprehensive assessment of safety or a basis for individual medical decisions.

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

The primary result describes average BPI Interference Scores during follow-up, adjusted for baseline and combined across the specified time points. The posted arm averages were lower in both LAMP groups than in usual care, and the registry’s mixed-model estimates for the two intervention-versus-usual-care contrasts were negative. Since higher scores indicate worse functioning, the direction of those comparisons corresponds to lower reported interference in the intervention groups under the reported contrast ordering.

That statistical pattern does not establish the size of a meaningful change for an individual. The registry does not report a clinically important difference threshold for the primary scale, nor does an average reveal how many participants improved, stayed similar, or worsened. The estimates also do not imply that every participant in an intervention arm had a better outcome than every participant receiving usual care.

The findings are specific to the participants enrolled, the intervention formats tested, the usual-care comparator, and the follow-up period described in the registry. The trial was open-label, and its primary outcome was participant-reported. Expectations and awareness of assignment may affect reported outcomes in general, although the registry results alone cannot quantify that possibility. The entry does not provide enough information to assess how representative the enrolled participants were or how results might differ in other settings.

The registry’s model-based analyses and the unadjusted recalculations are not identical procedures. The former are the trial’s own reported analyses; the latter are descriptive checks using posted summary statistics. Neither resolves the missing information about multiplicity, missing data, model details, or clinical-importance thresholds. The results support an account of observed group-level differences, not a guarantee of a particular outcome for an individual or a recommendation about care.

18. Why This Trial Matters Statistically

This trial presents a useful statistical comparison because it evaluates two delivery formats for a behavioral program against usual care, while also comparing the formats with each other. The primary outcome uses a repeated follow-up summary rather than a single endpoint measurement. That design makes the contrast relevant to the average pattern over the specified follow-up period, while requiring careful attention to baseline adjustment, repeated measurements, and the definition of the weighted average.

The registry also illustrates why arm summaries, model-based estimates, confidence intervals, and p-values need to be read together. A group mean describes an average on the scale; a model-based difference describes a specified contrast under the analysis; and a confidence interval indicates its precision under the model. None alone answers whether a difference is important to participants. Comparing the recalculation with the sponsor’s model highlights that results can differ in construction even when they address the same broad question.

The trial’s multiple secondary outcomes offer a broader view of pain-related functioning and other domains, but they also raise multiplicity and interpretation issues. Without a reported adjustment or testing hierarchy, secondary p-values should not be treated as though each were a stand-alone confirmatory test. Similarly, absent documentation on missing data and analysis populations limits the degree to which readers can assess robustness.

For biostatisticians and clinical researchers, the record is a reminder that transparent reporting of estimands, model specifications, multiplicity strategy, missing-data methods, and clinically meaningful thresholds is essential to interpreting results. The posted findings are informative at the level of the reported averages and contrasts, while important design and analysis details remain unavailable in the registry record.

19. 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.

Several limitations specific to this trial affect interpretation. The study is open-label, and the primary endpoint is based on participant-reported pain interference. In general, awareness of assignment can influence expectations and self-reported outcomes. The registry record does not describe blinded outcome assessment or provide information that would quantify any such influence.

The primary outcome combines measurements over 10 weeks, 6 months, and 12 months, but the weights assigned to these time points are not reported. The statistical model is identified as a mixed model, but details needed to reproduce it are not included. These omissions make it difficult to determine exactly how time, within-participant correlation, and baseline adjustment contributed to the reported estimates.

The record does not report the original sample-size justification, the planned analysis populations, the amount or handling of missing data, or the protocol’s full statistical analysis plan. It also does not report a clinically meaningful difference threshold for the primary measure. These gaps restrict assessment of whether the analyses followed the original plan, how sensitive results might be to missingness, and whether the observed score differences are meaningful in practical terms.

The control arm was usual care, which may vary across participants; details of that care are not reported. The trial title describes a pragmatic, multisite study, but the number of sites and information on participant characteristics are not reported in the registry record. The record therefore offers limited detail for judging generalizability. Finally, multiple secondary outcomes and contrasts are listed without a reported multiplicity strategy, which reduces the confirmatory weight of isolated secondary findings.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: Learning to Apply Mindfulness to Pain — NCT04526158.
• Registry record last updated 2024-11-05; status last verified 2024-10.
• Results first posted 2024-11-05.
• 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.

23. Record Summary

NCT04526158 is a completed, randomized, open-label, parallel-group trial sponsored by the United States Department of Defense. It enrolled 811 participants and compared Mobile+Group LAMP, Mobile LAMP, and Usual Care for chronic pain. The primary endpoint was baseline-adjusted change in BPI Interference Score, summarized as a weighted average over 10 weeks, 6 months, and 12 months; higher scores indicate worse functioning.

The registry reports lower primary outcome averages in both intervention groups than in usual care, alongside mixed-model intervention-versus-usual-care estimates of -0.4 and -0.7. The record also lists secondary outcomes spanning pain intensity, physical function, and other health and functioning measures. The interpretation is limited by unreported details on the original sample-size rationale, missing-data methods, analysis populations, model specifications, and multiplicity procedures. The record does not provide a threshold for clinically meaningful change.