the Effect of Reflexology in Migraine Patients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for the Effect of Reflexology in Migraine Patients (NCT06828315), a randomized na study. The primary outcome is Visual Analog Scale (VAS).

2. Clinical Question

This is a question about a group-level outcome at the stated endpoint. It does not establish whether every participant experienced a change, nor does the registry record explain how individual changes from the beginning to the end of the study were analyzed. The posted primary comparison is between the experimental and control groups at the end of the intervention. Its interpretation therefore depends on the randomized design and on how well the groups were followed and measured, details that are not fully described in the registry record.

3. Trial Design

The registry record describes a randomized, triple-masked, parallel-group trial. Participants were assigned to an experimental group receiving foot reflexology or a control group receiving routine treatment and medical follow-up. The record lists 39 participants in each group for the posted primary outcome. It reports enrollment of 78 and a completed status. The study start date is 2024-10-10, and the primary completion date is 2024-11-15.

The planned intervention consisted of 10 reflexology sessions, delivered twice a week. The primary outcome was assessed at the end of the 5-week intervention. The study description says participants in both groups were evaluated at the beginning and end using a Patient Information Form, the Migraine 24-Hour Quality of Life Scale (QoLQS), the Visual Analogue Scale (VAS), and the Fatigue Severity Scale (FSS). The posted primary result, however, is the end-of-intervention VAS score. Results for the other described measures are not reported in the registry record.

“Randomized,” “triple-masked,” and “parallel” are design labels recorded by the trial registry. The registry record does not explain the randomization procedure, concealment of allocation, who was masked, or how masking was maintained. It also does not report the eligibility criteria in detail, group-specific baseline characteristics, adherence to sessions, or the handling of deviations from the planned intervention. These omissions limit how much can be assessed about implementation and comparability from the record alone.

The control group did not receive reflexology during the study, and the record says it would be offered after completion to control-group patients willing to receive it. The posted primary comparison pertains to the end of the intervention; subsequent outcomes are not reported in the registry record. The trial's original sample-size assumptions and detailed statistical analysis plan are also 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.

Pre-Intervention (Baseline)

Post-Intervention (At the End of Week 5)

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 Visual Analog Scale (VAS), measured over At the end of the 5-week intervention.

The primary endpoint is pain intensity measured with the Visual Analog Scale (VAS) for Pain at the end of the 5-week intervention. The registry describes the VAS as a horizontal line anchored by “no pain” at 0 and “worst imaginable pain” at 10. Participants mark the point that represents their perceived pain intensity, producing a score from 0 to 10. Higher scores indicate greater pain severity and a worse outcome; lower scores indicate less pain and a better outcome.

The VAS is used as a direct, continuous measure of perceived pain intensity. In general, a continuous score can retain more gradation than a simple category such as improved or not improved, allowing researchers to compare group averages. The score remains a participant-reported measure: it records perceived pain, not an objective measurement of a biological process. The endpoint therefore addresses the average reported pain intensity in each group at the specified assessment, rather than the experience of every individual or the persistence of a result over longer follow-up.

The registry description says the VAS was administered at the beginning and end of the study, but the posted primary result is the end-of-intervention group comparison. The record does not report a baseline-adjusted estimate or a change-score analysis. The scale's possible score range and the direction of better outcomes are described, but no threshold for a clinically important difference is reported in the registry record.

7. Results Posted in the Registry

• Experimental Group: mean 4.15 versus 7.46 on control; difference -3.31 (95% CI -4.00 to -2.62), standardized effect d = -2.13; z-test p = <0.001.

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record posts group means and standard deviations for the primary continuous outcome, along with a mean difference, an interval estimate, and an unadjusted p-value. It does not report enough detail to identify the statistical test or the complete analysis procedure used for the sponsor's analysis. The explanations below describe the general meaning of these statistics, not an undocumented method used by the trial team.

What does a mean describe?

In general, the mean is the arithmetic average of the observed scores in a group. For this endpoint, the reported means are 4.15 for the experimental group and 7.46 for the control group. Because the VAS is scored so that lower values indicate less pain, the direction of these group averages is straightforward to interpret. A group mean does not reveal whether scores were similar for most participants or whether a smaller number of high or low scores influenced the average.

The standard deviation describes how spread out individual scores are around their group mean. The reported standard deviations are 1.63 in the experimental group and 1.48 in the control group. In general, a standard deviation is a description of variability among observations, not the uncertainty in the estimated mean itself. The registry record does not provide distributions, individual participant data, or additional summaries such as medians and ranges.

What does the mean difference represent?

In general, a mean difference expresses the separation between two group averages on the outcome's original scale. The posted estimate is -3.31 for the experimental group relative to the control group. The negative sign indicates a lower average in the experimental group under that comparison's direction. Since lower VAS values represent less pain, the direction corresponds to lower mean reported pain in the experimental group at the endpoint. The estimate remains a group-level contrast; it is not an estimate of an individual participant's change.

The registry record also lists a standardized effect estimate of -2.126. In general, a standardized effect expresses a difference in units of a measure of variability rather than in the outcome's original scale. That can help describe the size of a contrast without using VAS points, but it does not replace the original-scale estimate or establish clinical importance. The record does not give a clinical threshold for interpreting either estimate.

How should the p-value be read?

In general, a p-value describes how compatible the observed data are with a specified statistical null model, under the assumptions of the analysis. It is not the probability that the null hypothesis is true, and it does not state the probability that the result will replicate. The registry reports an unadjusted p-value of <0.001. “Unadjusted” means the posted value is not reported as corrected for multiple comparisons. Whether an adjustment was planned or whether additional analyses were conducted is not reported in the registry record.

A small p-value does not measure the size or practical importance of a difference. The mean difference and its interval are more directly useful for describing the magnitude and uncertainty of the endpoint estimate. The p-value also depends on the analysis assumptions, and the registry record does not identify the test or provide diagnostics that would allow those assumptions to be evaluated.

What is the role of the interval estimate?

In general, a confidence interval gives a range of estimates compatible with the data and a stated procedure, while conveying sampling uncertainty. The posted interval for the mean difference extends from -4.001 to -2.619. Its endpoints are on the VAS scale and use the same direction as the mean difference. The registry record does not state the confidence level, so a percentage label should not be inferred. An interval also does not account automatically for every possible source of uncertainty, such as bias from missing data or limitations in trial conduct.

What cannot be recovered from the posted methods?

The registry record does not report whether the primary comparison was adjusted for baseline VAS, how missing outcomes were handled, which analysis population was used, or whether assumptions were checked. It does not describe imputation, exclusions after randomization, or the treatment of protocol deviations. The record lists zero analysis entries, which leaves no detailed analysis description to evaluate. The result can therefore be explained from the posted summary statistics, but the precise model and analysis pathway are not reported in the registry record.

General statistical interpretation should distinguish the estimate from its uncertainty and from the study's design limitations. The reported mean difference describes the observed endpoint contrast; the interval describes uncertainty under an unspecified interval procedure; and the p-value is an unadjusted test result. None of these alone resolves concerns about missing outcomes, masking, allocation procedures, or whether results for other planned measures were selectively reported. The registry record does not report the trial's original statistical plan, so those questions remain open.

10. Confidence Intervals and Precision

The posted mean difference is -3.31 VAS points, with an interval from -4.001 to -2.619. This interval lies on the same scale as the outcome and retains the comparison direction of experimental group relative to control group. Its negative values correspond to a lower mean score in the experimental group. The registry record does not report the confidence level for this interval, so it is not possible to identify it as a particular conventional confidence interval from the record alone.

In general, an interval communicates uncertainty around an estimated group contrast. A relatively narrow interval indicates more precision than a wider interval under the same method and scale, but precision is not the same as freedom from bias. The posted interval does not capture uncertainty from possible differences in treatment delivery, outcome collection, missing data, or analysis choices unless those features were handled in the method used, which is not described in the registry record.

The group summaries include standard deviations of 1.63 for the experimental group and 1.48 for the control group. These describe variation in the observed VAS scores; they are not confidence intervals for the means. The posted comparison also reports an unadjusted p-value of <0.001. That value is evidence relative to the test's null model, but it does not substitute for considering the estimated magnitude and interval.

The endpoint is measured at the end of the 5-week intervention. The registry record does not report precision estimates for fatigue, quality of life, or longer-term pain outcomes. It also does not report the interval method, a baseline-adjusted estimate, or sensitivity analyses. Thus, the interval helps characterize statistical uncertainty in the posted primary contrast, while leaving important sources of uncertainty unaddressed in the record.

11. 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 planning figures are participants per arm, not total event counts. They are illustrations based on the observed effect and are not the trial's original sample-size justification. The planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. Each planning scenario uses a stated fraction of the observed effect: 100% of the observed effect, 75% of the observed effect, or 50% of the observed effect.

• For planning for 100% of the observed effect, the entries are 4 participants per arm for 80% power and 5 participants per arm for 90% power.
• For planning for 75% of the observed effect, the entries are 7 participants per arm for 80% power and 9 participants per arm for 90% power.
• For planning for 50% of the observed effect, the entries are 14 participants per arm for 80% power and 19 participants per arm for 90% power.

In general, power is the probability that a planned study will detect an effect of the specified size under its assumptions if that effect is present. The 80% and 90% columns describe two different planning targets: the chance of detecting the target effect under the model is higher for the 90% target, which requires more participants in these scenarios. Smaller effects are harder to distinguish from random variation, so planning to detect a smaller effect requires more participants.

These are planning illustrations, not observed power. They are calculated from the observed effect and should not be interpreted as evidence that the trial was designed with these assumptions. The trial's original sample-size assumptions are not reported in the registry record. The illustration also depends on its stated statistical assumptions and does not account for unreported features such as missing outcomes, departures from equal allocation, or adjustments to the analysis.

12. 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 = -3.310; pooled standard deviation σ = 1.557.
2. n = 2 × (1.96 + 0.842)² × 1.557² / -3.310² = 3.5, rounded up to 4 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 <- -3.31                      # observed difference in means
sigma <- 1.55680763101932                     # 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(6828315)
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 = 4 (80% power), 5 (90% power)
 75% of observed effect: n per arm = 7 (80% power), 9 (90% power)
 50% of observed effect: n per arm = 14 (80% power), 19 (90% power)
power.t.test: 4.7 
Simulated power at n = 4 per arm: 0.710 (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.

13. Multiplicity, Missing Data and Analysis Populations

The registry record describes pain, fatigue, and quality of life as outcomes of interest. It posts the primary VAS pain result, but secondary outcome results are not reported in the registry record. The record lists zero posted secondary outcomes and zero analysis entries. It does not clarify how many outcomes were originally planned beyond the descriptions in the study summary, or whether any outcomes were changed, omitted, or analyzed but not posted.

Multiplicity arises when several outcomes, time points, groups, or analyses are tested. In general, conducting more tests can increase the chance that at least one result appears statistically significant by chance. Researchers may plan methods to address that issue, such as identifying a primary outcome in advance or adjusting statistical tests. The registry record does not report a multiplicity strategy. The p-value attached to the primary comparison is explicitly unadjusted, so it should be read as the posted unadjusted result, not as evidence that multiplicity was addressed.

Missing-data methods are also not reported in the registry record. It does not state whether every randomized participant contributed an endpoint score, how unavailable scores were handled, or whether any imputation or sensitivity analysis was used. The posted outcome groups each list 39 participants, but the record does not explain whether that reflects everyone randomized, everyone assessed, or the analysis population used. It also does not identify an intention-to-treat, per-protocol, or other analysis population.

In general, the handling of missing observations can affect a group comparison when the likelihood of missingness is related to outcome or group assignment. Without participant flow, reasons for missingness, and the analysis method, the potential influence cannot be assessed from the posted record. Likewise, the registry's triple-masked label does not describe which people were masked or whether masking remained intact.

These reporting gaps do not establish that the trial was conducted improperly; they identify information that is not available in the registry record. They limit assessment of whether the reported primary comparison reflects the planned analysis and how robust it is to missing data or multiple outcome testing.

14. 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 no serious adverse events among the 39 participants at risk in the experimental group and no serious adverse events among the 39 participants at risk in the control group. It also reports zero other adverse events in each group and zero deaths in each group. These are the safety counts recorded for the groups, not proof that no adverse event could occur.

In general, an adverse-event count depends on how events were defined, sought, and recorded, as well as on the time participants were observed. The registry record does not describe the adverse-event collection method, the observation window for safety, event severity criteria, or whether events were assessed as related to the intervention. No serious adverse-event terms are listed. The record does not provide event narratives or information about withdrawals related to adverse events.

The counts should therefore be read as the reported safety information for this trial, not as a complete estimate of risk or evidence about safety in other settings. The registry record reports a completed study and an endpoint at the end of the 5-week intervention, but does not specify whether safety surveillance continued beyond that endpoint. Because the record does not provide further safety detail, the extent of monitoring and the ability to detect uncommon or delayed events cannot be assessed.

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

The posted primary result describes lower mean pain scores at the end of the intervention in the experimental group than in the control group. The mean VAS score was 4.15 in the experimental group and 7.46 in the control group; the mean difference was -3.31, with an interval from -4.001 to -2.619 and an unadjusted p-value of <0.001. On the scale described in the registry, lower scores indicate less reported pain. These statistics summarize the observed group comparison at that assessment.

They do not establish that every participant's pain decreased, quantify individual responses, or show how participants changed from baseline. The posted comparison is an end-of-intervention contrast; the registry record does not report a baseline-adjusted estimate or a change-score result. The confidence level and method for the interval are not stated, and details of the primary statistical test are not reported. Those omissions restrict how fully the precision and analysis can be evaluated.

The result also does not answer the study summary's questions about fatigue or quality of life. Those measures are described as assessed, but their results are not reported in the registry record. Nor does the result establish whether any difference persisted after the intervention, since later outcome results are not reported. The registry record says reflexology would be offered to willing control-group patients after study completion, but no subsequent comparison is posted.

The randomized design is relevant to interpreting a group contrast, but the record provides limited detail about randomization, masking, adherence, participant flow, missing data, and analysis populations. It is not possible to use the posted result alone to resolve those uncertainties or to determine how well the study findings generalize beyond the participants and circumstances described. No clinical-importance threshold is reported, so the statistical difference should not automatically be treated as a measure of practical importance.

In short, the registry record documents a lower average VAS score in the reflexology group at the specified endpoint and reports statistical evidence for a group difference. It does not establish broader outcomes, long-term effects, individual benefit, or the result's clinical importance. Those are distinct questions requiring information not reported in the registry record.

16. Why This Trial Matters Statistically

This trial is statistically notable because the registry reports a randomized comparison using a continuous, participant-reported pain measure and presents group means, standard deviations, an estimated mean difference, an interval, and an unadjusted p-value. Together, these summaries allow readers to consider both the direction and magnitude of the observed group contrast, rather than relying only on a significance label. The direction is interpretable because the record specifies that lower VAS scores indicate less pain.

The design also illustrates why an endpoint needs to be read in context. The primary result concerns pain intensity at the end of the 5-week intervention, while the trial description mentions fatigue and quality of life as additional questions. Since results for those outcomes are not reported in the registry record, the posted evidence addresses only a portion of the questions described. A statistically clear result for one endpoint cannot stand in for results on other outcomes.

The record further shows the importance of distinguishing a trial's observed result from a planning calculation. The sample-size illustrations use the observed effect under stated assumptions; they do not describe the trial's original design rationale and are not observed power. The original sample-size assumptions are not reported in the registry record. This distinction matters because post hoc planning based on an observed effect answers a different question from a prospective design calculation based on a prespecified target.

Finally, the record makes visible the limits of registry-level summaries. Important details about the analysis, missing data, outcome reporting, and trial conduct are not reported. Statistical interpretation is strongest when estimates are considered alongside their uncertainty and the transparency of the methods. The posted contrast can be described precisely, while unresolved design and reporting questions remain part of its interpretation.

17. 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 posted primary result is an end-of-intervention comparison. The registry record does not report longer-term pain outcomes, so persistence of the observed group difference cannot be assessed. Although fatigue and quality of life were named in the study description, their results are not reported in the registry record. This leaves the available outcome evidence narrower than the set of questions described.

The population is described as individuals diagnosed with migraine, but diagnostic criteria, age range, recruitment setting, eligibility criteria, and baseline characteristics are not reported in the registry record. The protocol details for reflexology, including session duration and provider qualifications, are also not reported. The control condition is described as routine treatment and medical follow-up, but its content and consistency are not explained.

Randomization and triple masking are recorded as design features, but procedures for allocation, concealment, and masking are not described. The registry record does not report adherence, participant flow, reasons for any missing outcome data, or whether the posted groups include everyone randomized. It also does not identify the analysis population or explain how missing observations were handled.

The record does not report the statistical test, baseline adjustment, assumption checks, multiplicity plan, or original sample-size justification. The posted interval's confidence level is not stated. These gaps limit evaluation of the statistical analysis and its robustness. The study status is completed, but the primary outcome is reported at the end of the 5-week intervention only. The registry record says reflexology would be offered to willing control-group patients after completion; it does not report outcomes after that point.

18. Related Tutorials

19. Related Statistical Calculators

20. Sources

• ClinicalTrials.gov: the Effect of Reflexology in Migraine Patients — NCT06828315.
• Registry record last updated 2026-03-04; status last verified 2026-02.
• Results first posted 2026-03-04.
• 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.

21. Record Summary

The registry record describes NCT06828315, “the Effect of Reflexology in Migraine Patients,” as a completed randomized, triple-masked, parallel-group trial sponsored by Muş Alparslan University. Enrollment was 78. The study start date was 2024-10-10, and primary completion was 2024-11-15. The intervention was foot reflexology alongside routine migraine treatment, compared with routine treatment and medical follow-up alone.

The posted primary outcome is VAS pain intensity at the end of the 5-week intervention. Mean scores were 4.15 in the experimental group and 7.46 in the control group, with a mean difference of -3.31 and an interval from -4.001 to -2.619. The unadjusted p-value was <0.001. The registry record does not report the interval's confidence level, detailed analysis methods, or results for the described fatigue and quality-of-life outcomes.

Safety counts show zero serious adverse events, zero other adverse events, and zero deaths reported in either group. The record does not describe the safety monitoring methods. The primary comparison is therefore interpretable as a posted endpoint contrast, with important details about analysis, missing data, and other outcomes not reported in the registry record.