Potential of an Experimental Mouthwash Formulation to Reduce Dry Mouth Symptoms: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Potential of an Experimental Mouthwash Formulation to Reduce Dry Mouth Symptoms (NCT02641912), a randomized na study. The primary outcome is Mean Response to the Question 1 'Relieving the Discomfort of Dry Mouth' in Product Performance and Attributes Questionnaire 3 (PPAQ3) at 120 Minutes(Mins) Post Treatment on Day 8.

2. Clinical Question

The study addressed a short-term, self-reported symptom question: the relative ratings of dry mouth relief after use of the experimental mouthwash or mineral water. The primary assessment was a single questionnaire item at a specified time after treatment, rather than a direct measurement of saliva production or a broad measure of health status. The rating scale ran from poor to excellent, with a separate “not applicable” response.

The comparison is between two different product-use experiences. The mouthwash was rinsed and spat out, while the water was sipped; at-home water use was allowed as often as required. The posted record therefore describes a comparison of the study’s product-use regimens, not a comparison in which all aspects of use were identical.

The trial was randomized and parallel-group, and its brief summary says that randomization was stratified by Sjogren’s Syndrome status. The record does not provide further details about the participants’ characteristics or the eligibility criteria. The clinical question is consequently best read as a question about ratings among the enrolled study participants, not as a result established for every person experiencing dry mouth.

3. Trial Design

The registry describes a randomized, single-center, parallel-group study with two treatment arms: Experimental Mouthwash and Mineral Water. The brief summary describes the study as examiner blind and stratified by Sjogren’s Syndrome status. The masking field is recorded as single; the registry record does not give further detail about who was masked or how masking was maintained. The study is listed as completed, with enrollment of 100.

The summary describes a 7-day study, while the primary outcome is specified at 120 minutes after treatment on Day 8. The primary outcome analysis included 52 participants in the Experimental Mouthwash arm and 37 in the Mineral Water arm. Those analyzed counts differ from the numbers listed as at risk for adverse events, which were 53 and 47, respectively. The record does not explain the differences between these outcome and safety populations.

The experimental treatment was used as a rinse: participants used 15 mls for 30 seconds and spat it out. The arm description says that no immediate water rinse was permitted after product use. The mineral-water arm involved a measured 15mls sip during supervised use, with water available as often as required at home. The arm description says the mouthwash was used at home with a maximum of two doses, but the registry record does not give additional detail on the complete dosing schedule.

The primary analysis population is described as intent-to-treat, including randomized participants who received study treatment at least once and provided at least one post-baseline efficacy assessment. For this outcome, only participants with an assessment for the specific question were analyzed. The record does not report the original sample-size justification, detailed allocation procedures, a full statistical analysis plan, or interim analyses. The phase field is listed as NA.

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: A total of 104 participants were screened. Out of which 100 participants were randomized and stratified based on confirmed Sjögren's syndrome status (Yes\[Y\]/No\[N\]).

Overall Study

Analysis population for the primary outcome, as defined in the registry: Intent-to-treat (ITT) population which included all participants who were randomized, received study treatment at least once \& provided at least one post-baseline (post treatment) assessment of efficacy. Number of participants analyzed for this outcome is the part of ITT population for specific question at specific time point.

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 Mean Response to the Question 1 'Relieving the Discomfort of Dry Mouth' in Product Performance and Attributes Questionnaire 3 (PPAQ3) at 120 Minutes(Mins) Post Treatment on Day 8, measured over 120 mins post treatment on Day 8.

The primary endpoint is the mean response to Question 1, “Relieving the discomfort of dry mouth,” in Product Performance and Attributes Questionnaire 3 (PPAQ3), measured 120 minutes after treatment on Day 8. Participants rated the question on a scale where 1 meant poor, 2 fair, 3 good, 4 very good, and 5 excellent; N/A meant not applicable. The outcome is the average of these scale responses in each treatment arm.

A questionnaire rating captures the participant’s own assessment of symptom relief. That makes it relevant to a question about perceived discomfort, but it is not an objective measure of dryness or a direct measure of the underlying cause of symptoms. A group mean also compresses individual responses into one summary: it does not show how many participants selected each response category or how varied personal experiences were beyond the reported standard deviations.

The Day 8 time point and the 120-minute interval define the scope of the result. It describes ratings at that particular assessment, rather than the entire course of symptoms during the study or longer-term experience. The registry record does not report a threshold for a clinically important change on this scale, so the size of a mean difference cannot by itself be classified as clinically important from the posted information.

7. Results Posted in the Registry

• Mineral Water: mean 1.89 versus 2.50 on control; difference -0.61 (95% CI -1.08 to -0.14), standardized effect d = -0.56; z-test p = 0.011.

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.

Mean Response to the Question 1 'Relieving the Discomfort of Dry Mouth' in Product Performance And Attributes Questionnaire 2 (PPAQ2) at 30 Mins Post Treatment on Day 8

• 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 deviations.
• Result:
  • Mineral Water: mean 2.26 versus 2.92 on control; difference -0.66 (95% CI -1.12 to -0.20), standardized effect d = -0.60; z-test p = 0.005.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for Mineral Water than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The registry lists a broad set of secondary outcomes, including ratings at other post-treatment times and responses to additional questionnaire items. There are 31 posted secondary outcomes. The pattern that can be assessed from the numeric comparison available in the record is directionally consistent with the primary result: the mean response is higher in the Experimental Mouthwash arm than in the Mineral Water arm for that additional assessment.

The secondary outcomes address related but not identical aspects of reported product performance and dry mouth relief, and they are measured at different times. Agreement in direction across related ratings can provide context for the primary result, but it does not make each measure an independent confirmation. Responses from the same participants and related questionnaire items may be correlated, and the results should be understood as a collection of related analyses rather than many separate trials.

The registry record does not provide numeric results for every listed secondary outcome in the information available for this analysis. It is therefore not possible to describe a comprehensive pattern across all secondary endpoints, determine whether any results conflict, or assess how many comparisons produced statistically notable findings. The unreported results should not be presumed to match the reported direction.

Multiplicity matters because the more outcomes and comparisons examined, the greater the opportunity for apparently notable findings to occur by chance. The registry record does not report whether secondary analyses were adjusted for multiple comparisons or identify a hierarchy that would control the interpretation of those tests. Consequently, unadjusted secondary results carry less weight than a clearly specified primary analysis, especially when many outcomes are considered. They are best treated as supportive or exploratory context unless a multiplicity plan and fuller results are available.

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

• Mean Response to the Question 1 'Relieving the Discomfort of Dry Mouth' in Product Performance And Attributes Questionnaire 2 (PPAQ2) at 30 Mins Post Treatment on Day 8
• Mean Response to the Question 1 'Relieving the Discomfort of Dry Mouth' in PPAQ3 at 60 and 240 Mins Post Treatment on Day 8
• Mean Response to Product Performance And Attributes Questionnaire1(PPAQ1) at 5 Mins Post Treatment on Day 8
• Mean Response to Question(Q) Number 2 to 11 (Q2 to Q11) From PPAQ2 at 30 Mins Post Treatment on Day 8
• Mean Response to Question (Q) Number 2 to 14 (Q2-Q14) From PPAQ3 at 60 Mins. Post Treatment on Day 8
• Mean Response to Question (Q) Number 2 to 14 (Q2-Q14) From PPAQ3 at 120 Mins. Post Treatment on Day 8
• Mean Response to Questions (Q) Number 2 to 14 (Q2 to Q14) From PPAQ3 at 240 Mins. Post Treatment on Day 8
• Mean Response to Product Performance And Attributes Questionnaire 4(PPAQ4) Prior to Treatment on Day 8

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is continuous: each participant’s response is a score on an ordered rating scale, and the registry reports a mean and standard deviation for each arm. A mean summarizes the average response, while the standard deviation describes the spread of individual scores around that average. Neither quantity shows the complete distribution of responses. In particular, group means do not reveal whether ratings were concentrated in a few categories or distributed across several categories.

The registry’s reported comparison used ANOVA and described its parameter as a least-square mean difference. In general, analysis of variance compares mean outcomes across groups. A least-square mean is a model-based group mean; depending on the model, it can account for factors included in that model. The registry record does not report the model specification or the factors included, so the precise adjustments behind this estimate cannot be determined from the record. The reported difference of 0.63 is in the direction of a higher mean response for Experimental Mouthwash than for Mineral Water, consistent with the order of the groups in the registry analysis.

A separate unadjusted re-calculation compares the posted arm means directly. For clarity, the displayed re-calculated contrast uses Mineral Water minus Experimental Mouthwash, which gives -0.61. Reversing the order of subtraction reverses the sign but not the underlying distance between the means. This calculation uses the posted group means and standard deviations and does not represent a fitted ANOVA model. It is not a replacement for the sponsor’s reported analysis.

A standard error describes the uncertainty in an estimated quantity across repeated samples under a statistical model. The standard error of a group mean is smaller when the estimate is based on more participants, all else being equal, and is also affected by variation in participant scores. A standard deviation and a standard error answer different questions: the former describes participant-to-participant spread, while the latter describes precision of an estimated mean. The standard deviations in the registry are 1.057 for Experimental Mouthwash and 1.149 for Mineral Water.

A confidence interval gives a range of values compatible with the data under the assumptions of the analysis. In general, a 95% confidence interval is produced by a procedure that would cover the underlying parameter in 95% of repeated samples if its assumptions held. It is not a statement that there is a 95% probability that this particular fixed parameter lies in the observed interval. The sponsor’s interval is based on its ANOVA analysis; the re-calculated interval comes from the unadjusted summary-statistic comparison. Those intervals answer related but not necessarily identical inferential questions.

The reported p-value assesses how unusual results at least as incompatible with a null hypothesis would be under the specified model, if the null hypothesis and model assumptions were correct. It does not measure the probability that the null hypothesis is true, the probability that the result is due to chance, or the magnitude or importance of a difference. The registry’s ANOVA p-value and the unadjusted re-calculated p-value arise from different analyses, so they should not be expected to match exactly.

The trial describes random allocation, which is intended in general to reduce systematic differences between assigned groups. Stratification by Sjogren’s Syndrome status is also stated in the brief summary. The registry record does not report the allocation sequence, concealment details, or an analysis of balance across participant characteristics. It is therefore possible to describe the design features recorded, but not to verify their implementation from the registry information alone.

The primary population is defined in the registry as randomized participants who received study treatment at least once and had at least one post-baseline efficacy assessment. For a particular outcome, the analysis count is the portion of that population with an assessment for the question. This definition is narrower than simply including every randomized participant, and the primary analysis counts show that not everyone enrolled contributed a primary outcome value. The record does not give the reasons for absent assessments, methods for handling missing values, or sensitivity analyses.

Dispersion can affect how well a mean and a normal-based comparison describe the data. In general, over-dispersion means that observed variability is greater than a model assumes; if it is ignored, uncertainty may be understated. The posted standard deviations describe appreciable participant-level spread, but the record does not report checks of model assumptions, the response distribution, or an alternative analysis. Since the outcome uses a bounded rating scale, the mean is a useful summary but does not remove the need to consider the scale’s limits and distribution.

The planning illustrations use a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. They use the observed effect as a reference and consider detecting a stated fraction of that effect. These are general planning calculations based on the posted estimate, not a report of the original trial design. The registry record does not report the assumptions used by the investigators when deciding on the study’s original enrollment target.

11. Confidence Intervals and Precision

The sponsor’s reported 95% confidence interval for the least-square mean difference runs from 0.17 to 1.10. It is entirely on the side of a higher mean response for Experimental Mouthwash, under the registry’s model and group ordering. The interval’s width shows that the estimate is not a single precisely known value: a range of positive differences remains compatible with the analysis.

The unadjusted comparison also has a confidence interval that excludes zero, according to the recalculation from posted summary statistics. It is important not to treat that interval and the sponsor’s ANOVA interval as interchangeable. The registry’s model details are not reported, and the re-calculation is a direct, unadjusted comparison. The two analyses can differ in their estimates and uncertainty while still pointing in the same direction.

Confidence intervals describe statistical precision, not clinical importance. The score scale runs from poor to excellent, but the registry record does not give a threshold for a difference that participants would regard as important. Thus, the interval can inform how compatible the data are with different sizes of mean difference, but the record alone does not establish which values would represent a meaningful improvement in experience.

Precision also depends on the number of participants contributing outcome values and the variability in their responses. The primary analysis included 52 participants in the mouthwash arm and 37 in the mineral-water arm, with standard deviations of 1.057 and 1.149. The analyzed counts are unequal, and the record does not fully explain missing outcome assessments. Generalizing the interval beyond the analyzed participants therefore depends on assumptions about the study design, the analysis model, and the missing data that cannot all be checked from the registry record.

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 illustrations are planning calculations, not observed trial outcomes. For this continuous outcome, the figures are participants per arm, not a total number of events. The listed scenarios plan for 100%, 75%, or 50% of the observed effect. For example, planning for 75% of the observed effect gives 91 participants per arm for 80% power and 121 participants per arm for 90% power. Planning for 50% of the observed effect gives 203 participants per arm for 80% power and 272 participants per arm for 90% power.

The calculations assume a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is the stated fraction of the observed effect. These assumptions are for the planning illustration; the original trial’s design assumptions and sample-size justification are not reported in the registry record.

In plain terms, 80% power means that a study planned this way would have an 80% chance of detecting an effect of the specified size at the stated significance level, if the assumptions and effect size used for planning were correct. The 90% power column describes the corresponding plan with a higher chance of detecting that specified effect, which requires more participants. Smaller effects are harder to distinguish from random variation, so planning to detect a smaller fraction of the observed effect requires more participants.

These figures are not observed power. They do not tell how much power the completed trial had after its results were known; they illustrate participant counts for hypothetical future planning under the stated assumptions.

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 = -0.610; pooled standard deviation σ = 1.096.
2. n = 2 × (1.96 + 0.842)² × 1.096² / -0.610² = 50.7, rounded up to 51 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 <- -0.61                      # observed difference in means
sigma <- 1.09600599356529                     # 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(2641912)
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 = 51 (80% power), 68 (90% power)
 75% of observed effect: n per arm = 91 (80% power), 121 (90% power)
 50% of observed effect: n per arm = 203 (80% power), 272 (90% power)
power.t.test: 51.7 
Simulated power at n = 51 per arm: 0.791 (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 sponsor’s primary comparison as an ANOVA least-square mean difference of 0.63, with a 95% confidence interval from 0.17 to 1.10. The interval is on the positive side for the reported group order, Experimental Mouthwash followed by Mineral Water. The registry reports a p-value of 0.008; the estimate and interval convey the direction and range of the model-based result without relying on that value alone.

The unadjusted re-calculation uses the posted arm means and standard deviations and expresses the contrast as Mineral Water minus Experimental Mouthwash. It gives -0.61, with an unadjusted p-value of 0.011. The negative sign follows from subtracting the mouthwash mean from the mineral-water mean. Expressed in the opposite direction, the contrast would have a positive sign.

The two estimates are not identical, but both describe a higher average rating in the mouthwash arm. The recalculation is a simple comparison of summary statistics; the sponsor’s reported ANOVA is the registry’s model-based analysis. The record does not report enough detail to explain exactly why the numerical estimates differ, and no discrepancy is flagged in the registry data. For inferential interpretation, the sponsor’s own analysis is the primary reported result; the recalculation is a transparent, unadjusted comparison rather than a substitute for it.

15. Multiplicity, Missing Data and Analysis Populations

The registry lists 32 outcome measures, including the primary outcome, and 31 posted secondary outcomes. Examining many outcomes creates a multiplicity issue: even when no underlying differences exist, a larger set of statistical tests makes it more likely that at least one result will appear unusual by chance. In general, planned methods such as adjustment for multiple comparisons or a prespecified testing hierarchy can help control how such findings are interpreted.

The registry record does not report whether the sponsor adjusted secondary comparisons for multiplicity, whether outcomes were tested in a fixed order, or whether the primary outcome was protected within a broader testing plan. It also does not give a complete statistical analysis plan. The primary result should therefore be distinguished from the wider set of secondary questions, and individual secondary p-values should not automatically be read as confirmatory evidence.

The stated analysis population includes randomized participants who received study treatment at least once and provided at least one post-baseline efficacy assessment. For the primary question, the number analyzed was the subset with an applicable assessment. The registry does not explain why the primary outcome counts were smaller than enrollment, why the group counts were unequal, or how missing outcome values were handled. It does not report imputation methods, sensitivity analyses for missing data, or comparisons of participants with and without an outcome assessment.

Missing outcomes can affect an estimate if the chance of a missing assessment is related to a participant’s rating or treatment experience. In general, analyses based only on observed responses rely on assumptions about the unobserved responses. The registry record does not provide the information needed to assess those assumptions. The difference between outcome-analysis counts and adverse-event counts also means that the two types of results describe different analyzed populations.

The registry identifies the primary analysis as intent-to-treat, but its outcome-specific definition requires receipt of study treatment and at least one post-baseline efficacy assessment. The record does not state whether additional analysis populations were used or describe protocol deviations. These omissions limit assessment of the robustness of the inferential result, without changing what the posted primary analysis reports.

16. Safety Results

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

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 1% reporting threshold.

Most frequent non-serious adverse event terms

The registry records zero serious adverse events among 53 participants at risk in the Experimental Mouthwash arm and zero among 47 participants at risk in the Mineral Water arm. These are the serious adverse event counts posted for the arms during the study. They should be read alongside the numbers at risk, rather than as evidence that serious events are impossible or that risk is absent.

Other adverse events were recorded for 12 participants in the mouthwash arm and 4 in the mineral-water arm, among the respective at-risk counts of 53 and 47. The registry record does not provide the event descriptions in the information, nor does it establish that an event was caused by the assigned product. The counts are descriptive and do not by themselves determine the comparative safety profile.

Deaths are not listed as numerical counts in the registry information. They should not be interpreted as zero. The trial’s primary analysis counts also differ from the safety counts, so safety and efficacy figures refer to different numbers of participants. The study’s short duration and the details available in the registry limit what can be concluded from these safety summaries.

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

The posted primary result describes an average questionnaire rating of relief of dry mouth discomfort 120 minutes after treatment on Day 8. The mean was higher in the Experimental Mouthwash arm than in the Mineral Water arm, and the registry’s ANOVA estimate and 95% confidence interval are consistent with a positive difference in the reported group order. The simple unadjusted comparison also points toward a higher mean rating in the mouthwash arm.

That finding is specific to the study’s participants, products, use instructions, questionnaire item, and assessment time. It is not a direct measurement of saliva or an assessment of every aspect of dry mouth symptoms. The outcome was a self-reported rating on a scale from poor to excellent, with N/A available. A group average does not indicate that every participant had the same experience, nor does it show the proportion who gave each rating.

The registry record does not report a minimum clinically important difference for the scale. Statistical evidence that a mean difference is distinguishable from zero is not the same as evidence that the difference is important to participants. The record also does not provide longer-term results, so the Day 8 assessment cannot establish how ratings might change after the study period.

The comparison involved mouthwash use and mineral-water sipping, with differing instructions for supervised and home use. The result should not be generalized to other formulations, dosing patterns, populations, or settings without supporting evidence. The registry record does not provide detailed participant characteristics or enough information about missing outcomes and the model specification to resolve all questions about generalizability and robustness.

In short, the posted statistics show higher average ratings in the mouthwash arm for the primary assessment, with a model-based interval above zero. They do not, by themselves, establish the clinical importance, durability, or broader applicability of that difference, and they are not a basis for medical advice.

18. Why This Trial Matters Statistically

This trial illustrates how a clinical question can be framed around a patient-reported outcome rather than a laboratory measurement. The primary endpoint asks participants to rate relief of dry mouth discomfort, making the outcome directly relevant to their experience while also requiring careful attention to what the rating scale does and does not represent.

It also shows why the analysis method and direction of a contrast matter. The sponsor’s ANOVA reports a least-square mean difference in the order of Experimental Mouthwash and Mineral Water, while the unadjusted recalculation is expressed as Mineral Water minus Experimental Mouthwash. The signs differ because the subtraction order differs, not because the analyses point in opposite directions. Clear descriptions of group order help prevent a sign from being misread.

The study also provides a useful distinction between a reported trial analysis and a re-calculation from summary statistics. The sponsor’s model-based analysis is the registry result; the simpler comparison offers a check on the direction of the posted arm means but cannot reproduce an incompletely described model. That distinction is important whenever registry records provide summary results without a full statistical analysis plan.

Finally, the number of registered and posted secondary outcomes makes multiplicity and selective interpretation relevant. A primary result should be understood in the context of the outcome set, while secondary findings need appropriate caution if the testing plan is not reported. The record’s missing-data and analysis details also show why statistical significance alone is not a complete account of evidence. Estimates, uncertainty, outcome meaning, and limitations all contribute to a balanced reading.

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.

The study is described as single-center and short-term, with the primary assessment at a single time after treatment on Day 8. That limits the result to the specified setting and measurement occasion. The registry record does not report longer-term follow-up or participant characteristics in enough detail to assess how well the enrolled group represents other people with dry mouth symptoms.

The primary outcome is one self-reported questionnaire item. Although its response scale is described, the registry does not report validation details, a clinically important difference, or the distribution of individual responses. The mean and standard deviation summarize the groups but cannot show how many participants experienced a particular level of relief.

The study arms used different product-use procedures: a mouthwash rinse and a measured sip of water, with water available as often as required at home. As a result, the comparison reflects the specified regimens rather than an otherwise identical exposure. The registry record does not report enough detail to assess adherence to home-use instructions or the full product-use schedule.

Primary outcome counts were 52 and 37, whereas the adverse-event at-risk counts were 53 and 47. The record does not explain these differences, the missing outcome assessments, or how missing values were handled. In addition, the full ANOVA model specification, assumptions checks, multiplicity approach, and original sample-size justification are not reported in the registry record. These gaps limit independent assessment of the analysis and its robustness.

There are many registered outcome measures, and numeric results for every secondary outcome are not available in the record used for this analysis. This restricts assessment of the full outcome pattern and the impact of multiple testing. The safety summaries also do not provide enough event detail to judge the nature or attribution of the other adverse events.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: Potential of an Experimental Mouthwash Formulation to Reduce Dry Mouth Symptoms — NCT02641912.
• Registry record last updated 2017-07-11; status last verified 2017-06.
• Results first posted 2017-01-27.
• 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.

23. Record Summary

The registry describes a completed, randomized, single-center, parallel-group study of Experimental Mouthwash and Mineral Water in participants experiencing dry mouth symptoms. The primary endpoint was the mean rating of relief of dry mouth discomfort in PPAQ3, 120 minutes after treatment on Day 8. The primary outcome analysis included 52 participants in the mouthwash arm and 37 in the mineral-water arm.

The mean response was 2.5 for Experimental Mouthwash and 1.89 for Mineral Water. The registry’s ANOVA reported a least-square mean difference of 0.63, with a 95% confidence interval from 0.17 to 1.10. An unadjusted re-calculation from the posted arm summaries also points toward a higher mean rating in the mouthwash arm, but it is not a replacement for the sponsor’s model-based analysis.

Interpretation is limited by the outcome’s self-reported, single-item nature; the lack of a reported clinical-importance threshold; and missing details about the model, missing outcomes, multiplicity, and original design assumptions. The findings describe the posted assessment and should not be extended beyond the study setting and time point without further evidence.