Meibomian Gland Dysfunction Treatment: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Meibomian Gland Dysfunction Treatment (NCT04229888), a na na study. The primary outcome is Dry Eye Questionnaire 5 (DEQ-5) Score.

2. Clinical Question

The registry describes the purpose as evaluating treatments for Meibomian Gland Dysfunction. Its endpoint and sequence identify what was planned for assessment, but the available record does not provide numerical outcome results. In particular, it does not report an estimate that would allow a reader to quantify a change in dry-eye symptoms or separate the effects of the two treatments. A comparison between treatments would require a suitable design and analysis; the recorded sequence alone is not a randomized head-to-head comparison.

3. Trial Design

The registry record identifies this as a completed, single-group study with an enrollment of 14. The listed condition terms are Meibomian Gland Dysfunction and Dry Eye. The sponsor is Indiana University. The study start is recorded as 2020-02-26, and primary completion as 2021-03-25. The phase and allocation are recorded as NA, and masking is recorded as none.

All subjects were to receive light-based sham treatment and then LipiFlow treatment. This sequence matters for interpretation: the record does not describe independently assigned groups receiving one treatment or the other. Nor does it describe a randomized control group. The registry explicitly cautions that the arms are not a like-for-like control comparison. Consequently, a difference between measurements associated with the two treatment periods, if reported elsewhere, could not automatically be attributed to the treatment alone. Time, sequence, and other changes could also contribute.

The primary outcome is DEQ-5 score at 2 weeks. Secondary outcomes are Meibomian Gland Score and Tear Break-Up Time (TBUT). The record lists 3 outcome measures and 3 analyses, but the numeric estimates and analysis details are not reported in the registry record. Details such as the full schedule of assessments, eligibility criteria, participant characteristics, and handling of withdrawals are also not reported in the registry record.

The study status is completed, which describes its recorded administrative status rather than the availability or completeness of its results. A completed study can still have limited public reporting. The record does not provide enough statistical detail to reconstruct the analysis or determine how many participants contributed to each outcome.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Before assignment: 14 subjects total were enrolled which is less than what was expected (15) due to time constraints

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 Dry Eye Questionnaire 5 (DEQ-5) Score, measured over 2 weeks.

The primary endpoint is the Dry Eye Questionnaire 5 (DEQ-5) score at 2 weeks. The record describes it as a score on a scale and states that the total ranges from 0-22, with higher scores indicating increased dry eye. It is a patient-reported measure: its purpose is to represent dry-eye symptoms through questionnaire responses rather than through a physical measurement alone.

As a continuous outcome, the score can be described using a mean and a measure of variability. A mean gives a central summary for the observed scores; a standard deviation describes how spread out individual scores are around that mean. These are general statistical interpretations of the registered outcome type and summary measure. The registry record specifies mean and standard deviation, but does not report their numerical values for the endpoint.

A score at a stated follow-up time can describe the status of participants at that time. To interpret change, readers would need a baseline value and a clearly defined comparison, such as a within-participant change or a between-group contrast. Neither a baseline estimate nor a change estimate is reported in the registry record. The registered 2-week timeframe therefore identifies when the outcome is assessed, but does not by itself show whether scores changed, how much they changed, or how precisely any change was estimated.

The endpoint is relevant to the study's stated focus on dry eye, but a questionnaire score is not interchangeable with the secondary measures of Meibomian Gland Score or TBUT. Each measure captures a different aspect of the study's outcomes and should be interpreted on its own terms.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes the primary outcome as a continuous score and specifies mean with standard deviation as the summary. In general, a mean is the arithmetic center of a set of observed values. It is useful for conveying the average score, but does not reveal whether participants had similar scores or widely differing scores. The standard deviation describes the spread of individual observations around the mean. It is not the same as the uncertainty in the mean; that uncertainty also depends on the amount of outcome information and the analysis method.

For treatment studies, it is important to distinguish a score at follow-up from a change or contrast. A follow-up mean describes observed scores at a particular time. A change estimate compares measurements across times for the same participants, while a treatment contrast compares outcomes under different treatment assignments or conditions. These quantities answer different questions. The registry identifies a DEQ-5 assessment at 2 weeks but does not report a baseline estimate, a change estimate, or a numerical treatment contrast. The analysis used for the posted results is not reported in the registry record.

General explanation: a confidence interval communicates the statistical precision of an estimate under the assumptions of the analysis. A narrower interval indicates greater precision than a wider interval, but neither width alone nor inclusion of a null value establishes clinical importance. A p-value addresses compatibility with a specified null hypothesis, given the model and assumptions. It is not the probability that the null hypothesis is true and does not describe the magnitude of an effect. The registry record does not report confidence intervals or p-values for the registered outcomes.

Design determines which comparisons can be interpreted. This record describes one group and a fixed treatment sequence: light-based sham treatment, then LipiFlow. Since all subjects were to receive both, the names of the treatments do not represent randomized, independent comparison groups. General statistical reasoning indicates that a sequential comparison can be affected by order, time, and other changes occurring between assessments. A randomized parallel-group comparison can, under its design and assumptions, support a different kind of contrast. The record does not describe such a comparison, and its own note cautions that the arms are not like-for-like controls.

The registry lists enrollment of 14. Enrollment is not necessarily the same as the number analyzed for a particular endpoint. Reasons for missing measurements, the number with observed DEQ-5 data, and any method for handling missing data are not reported in the registry record. Without those details, readers cannot assess whether the analysis used all enrolled participants or whether missingness could affect the estimates.

The record also describes a planning illustration based on an observed effect, rather than the trial's own design. Its stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. The planning setup is not evidence that the trial was planned or conducted with those assumptions. No numerical observed effect, effect fractions, or resulting sample-size values are reported in the registry record. Such planning calculations are illustrative assumptions for future study planning, not observed power and not a retrospective measure of whether this study was adequately powered.

General explanation: sample-size planning asks how much information a proposed study might need to detect an effect under specified assumptions. Its result depends on the target effect, variability, allocation, significance threshold, power target, and analysis method. If the assumed effect is based on an observed estimate, that estimate may itself be uncertain. Planning values should therefore be distinguished from trial results and from the number actually enrolled. Here, the registry's planning description cannot be used to infer a numerical effect or the precision of the observed outcomes.

Finally, the record lists 3 outcome measures and 3 analyses, but does not identify the full analysis model, covariates, handling of repeated measurements, or any multiplicity procedure. Those omissions prevent independent reconstruction of the estimates. They also mean that general descriptions of statistical methods should not be mistaken for a claim about which methods were used in this study.

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("Subjects Treatment Light Based (Sham)", "Subjects Treatment LipiFlow")
n   <- c(14, 14)
m   <- c(11.8, 11.8)
sp  <- c(3.9, 4.4)
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  Subjects Treatment Light Based (Sham)  14  11.800  3.900  9.548  14.052
CARM  Subjects Treatment LipiFlow  14  11.800  4.400  9.260  14.340

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists a primary outcome, DEQ-5 score, and two secondary outcomes: Meibomian Gland Score and TBUT. It also lists 3 outcome measures and 3 analyses. When a study evaluates several outcomes, the chance of at least one apparently notable finding can increase if each is tested separately without a prespecified strategy. General approaches include identifying a primary outcome in advance, adjusting for multiple comparisons, or treating secondary analyses as exploratory. The multiplicity procedure used in this study is not reported in the registry record.

The designation of a primary endpoint helps clarify which outcome was intended to be central, but it does not resolve multiplicity questions about secondary endpoints or additional analyses. The registry does not report whether outcomes were measured at other time points, whether there were additional analyses, or how any such results were handled. The numeric results needed to evaluate the outcomes are also not reported in the registry record.

Missing-data methods and analysis populations are not reported in the registry record. Although enrollment is 14, the record does not state the number with observed values for each outcome, the reasons for any unavailable measurements, or whether an analysis included all enrolled participants. It also does not describe imputation, exclusions, or sensitivity analyses. These details matter because an analysis restricted to participants with observed outcomes can be misleading if the availability of data is related to the outcome or treatment experience.

The registry's primary outcome population field is not populated with a description. Thus, the exact analysis population for the DEQ-5 result is not reported in the registry record. Readers should not infer an intention-to-treat, per-protocol, or other analysis population without that information.

12. Safety Results

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

Deaths

Other (non-serious) adverse events

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

The registry record reports adverse-event figures separately for Light Based (Sham) Treatment and LipiFlow Treatment. For each listed group, 14 were at risk for serious adverse events and 0 were affected; 14 were at risk for other adverse events and 0 were affected. Deaths are recorded as 0 for each group. No serious adverse-event terms are listed.

These figures describe what the registry record reports; they do not establish that no adverse events occurred outside the recorded definitions, observation period, or reporting process. The adverse-event ascertainment window, definitions, and method of collection are not reported in the registry record. Nor does the record explain how events were attributed to one treatment when all subjects were to receive the sham treatment followed by LipiFlow. Because the treatment groups are not a like-for-like control comparison, their figures should not be interpreted as a randomized safety comparison.

Zero recorded events is not proof of zero risk. General statistical interpretation recognizes that event counts, particularly when limited, can leave substantial uncertainty about the range of possible event rates. The registry figures can be read as the reported counts, but they do not provide a comparative estimate or enough information to characterize safety beyond those recorded observations.

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

The registry record establishes that a completed study evaluated a sequence of light-based sham treatment followed by LipiFlow and registered DEQ-5 score at 2 weeks as its primary outcome. It also identifies Meibomian Gland Score and TBUT as secondary outcomes. This describes the study's focus and intended outcome measures; it does not, by itself, establish what happened to participants' scores.

Numerical outcome results are not reported in the registry record. There is no reported DEQ-5 mean, standard deviation, change, treatment contrast, or confidence interval from which to judge the direction, magnitude, or precision of an outcome. The secondary outcome estimates are not reported either. Therefore, the record cannot support a quantitative conclusion about the observed results.

The design matters as much as the choice of outcome. All subjects were to receive both treatments in the same order, and the study is described as single-group. This is not a randomized comparison of LipiFlow with a separate control group. Even if measurements differed across the sequence, the design would not by itself distinguish a treatment effect from other influences associated with time or order. The registry specifically cautions that the arms are not a like-for-like control comparison.

The adverse-event entries report 0 affected for serious events, 0 affected for other events, and 0 deaths in each listed group. Those are recorded counts, not proof that risk is absent. The reporting window and other safety methods are not reported in the registry record.

In short, the record provides useful information about the study's structure and registered measures, but not the numerical outcome evidence needed to estimate effects. It should not be read as showing either benefit or lack of benefit. Interpretation of any results would require the underlying estimates, their precision, analysis details, and a clear account of the sequential design.

14. Why This Trial Matters Statistically

This study illustrates why the design of a clinical trial must be understood before interpreting a treatment comparison. The registry names a sham treatment and LipiFlow, but describes one group receiving both in a fixed sequence. Treatment names alone do not create independent comparison groups. A result contrasting time periods in such a sequence would answer a different question from a randomized comparison between treatments.

It also illustrates the distinction between a registered outcome and a reported result. The DEQ-5 score is clearly identified as the primary endpoint, with a defined direction and assessment time. Yet without its numerical estimate and uncertainty, readers cannot assess the magnitude or precision of the outcome. Stating an endpoint is not a substitute for reporting the result.

The study also shows why enrollment, analysis populations, missing data, and adverse-event counts need separate interpretation. Enrollment is recorded as 14, but the number analyzed for each outcome is not reported. Adverse-event figures list no affected participants, but the reporting details needed to interpret those counts are not given. These are different pieces of evidence and should not be conflated.

More broadly, the record provides an example of how registry entries can support careful appraisal even when numerical results are unavailable. It allows readers to identify the study's outcome structure, treatment order, and limitations of the comparison. At the same time, the absence of estimates and analysis details places a firm boundary on what can be concluded. Statistical interpretation depends on both design and results; neither can replace the other.

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 limitation for interpreting the registry record is that numerical results for the primary and secondary outcomes are not reported in the registry record. No estimates of central tendency, variability, change, or precision are available. This prevents quantitative evaluation of the outcomes, regardless of the study's completion status.

The single-group, fixed-sequence design limits treatment attribution. All subjects were to receive light-based sham treatment followed by LipiFlow, and the registry states that the arms are not a like-for-like control comparison. Without a randomized control comparison, changes over time cannot be cleanly assigned to one treatment. The record does not describe a design feature that would address effects of order or time.

The registry does not report participant characteristics, detailed eligibility criteria, assessment schedules beyond the primary timeframe, or the analysis population. Although enrollment is 14, the number of participants contributing data to each outcome is not reported. Missing-data handling, exclusions, and sensitivity analyses are also not reported in the registry record.

Further statistical details are unavailable, including the outcome analysis model, treatment of repeated observations, covariate adjustment, and multiplicity procedures. These omissions make it impossible to reconstruct or independently assess the analysis. The registry's planning description does not supply numerical observed-effect or sample-size results that would clarify precision.

For safety, the record gives event counts but not the ascertainment window, definitions, collection methods, or attribution approach. Consequently, the reported zero affected counts should be understood as registry entries, not as a comprehensive characterization of risk. These limitations are specific to the information and design described in this record; they do not establish that unreported analyses or details do not exist elsewhere.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Meibomian Gland Dysfunction Treatment — NCT04229888.
• Registry record last updated 2022-03-29; status last verified 2022-03.
• Results first posted 2022-03-29.
• 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

NCT04229888 is a completed, single-group study sponsored by Indiana University. The registry records enrollment of 14, phase NA, allocation NA, and no masking. The study start is 2020-02-26, and primary completion is 2021-03-25. All subjects were to receive light-based sham treatment followed by LipiFlow.

The primary outcome is DEQ-5 score at 2 weeks; secondary outcomes are Meibomian Gland Score and TBUT. The DEQ-5 scale ranges from 0-22, with higher scores indicating increased dry eye. Numerical outcome estimates and analysis details are not reported in the registry record. The adverse-event entries record 0 affected for serious events, 0 affected for other events, and 0 deaths in each listed group. The fixed sequence and single-group design do not provide a randomized, like-for-like comparison of the treatments.