The Efficacy of a Toothpaste to Reduce Sensitivity: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Efficacy of a Toothpaste to Reduce Sensitivity (NCT00763269), a randomized phase 3 study. The primary outcome is Hypersensitivity Tactile(Yeaple Probe).

2. Clinical Question

The clinical question is specific to a measured response at the tooth, not to every aspect of sensitivity or to a participant’s overall experience. The tactile outcome used an electronic force-sensing probe to apply force to a hypersensitive tooth until pain was elicited. For each study subject, the score was the mean across two hypersensitive teeth.

The record also lists air-blast hypersensitivity outcomes at 4 weeks and 8 weeks. These provide additional measurements alongside the primary tactile result, but the registry record does not describe the direction of the air-blast scale. The outcomes should therefore be read according to their recorded values and comparisons without assuming, from this record alone, which direction represents improvement.

The record does not report fuller eligibility criteria, the number or characteristics of people screened, or participant characteristics at the beginning of the trial. It also does not describe how the two toothpastes were used. Those gaps limit how specifically the study population and treatment contrast can be characterized.

3. Trial Design

This was a Phase 3, randomized, double-masked, parallel-group trial listed as completed. The registry names Colgate Palmolive as the sponsor. The study start is recorded as 2008-09 and primary completion as 2008-12. Enrollment is listed as 626.

The trial compared two arms. Arm A is described as a sensitive toothpaste, with Triclosan, Silicon dioxide, and fluoride listed as its intervention. Arm B is described as a Triclosan control toothpaste, with Triclosan and fluoride listed. The record’s intervention labels classify both as drug interventions. The participant-facing masking arrangements, including who was masked, are not reported in the registry record. Details of the random sequence generation, allocation concealment, and the process used to assign participants are also not reported in the registry record.

The primary outcome was mean tactile hypersensitivity measured with a Yeaple Probe at 4 weeks. The registry describes the outcome as the mean score for two hypersensitive teeth per study subject. The two secondary outcomes are air-blast hypersensitivity at 4 weeks and at 8 weeks. The record lists four outcome measures and four analyses, although it names only two secondary outcomes in addition to the primary outcome. Further detail about the other listed measures is not reported in the registry record.

The registry gives group-level outcome summaries for the two arms. It also records an ANCOVA analysis for the primary and secondary comparisons, with p = 0.05 for each reported analysis. It does not give the ANCOVA estimates, interval bounds, covariates, or analysis populations. The original trial’s sample-size assumptions, any interim analyses, and the prespecified statistical plan are not reported in the registry record. The sample-size calculations presented with the posted results are planning illustrations based on the observed effect, not a record of the trial’s original design.

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: subjects were screened for medical and oral health criteria and then entered a 1 week washout before study treatment period.

Overall Study

Reasons for not completing this period:

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 Hypersensitivity Tactile(Yeaple Probe), measured over 4 weeks.

The primary endpoint is tactile hypersensitivity measured with an electronic force-sensing Yeaple Probe at 4 weeks. The probe applies increasing force to a hypersensitive tooth until the participant reports pain. The amount of force needed to elicit pain is recorded as the tooth’s hypersensitivity score. Each study subject’s score is the mean across two hypersensitive teeth.

The registry states that the score is expressed in units on a scale and that higher scores mean more grams of force were needed to elicit pain. In this measure’s defined direction, a higher score corresponds to lower hypersensitivity. That direction matters when interpreting the difference between the arm means: a positive difference favoring the experimental arm means the experimental group had a higher average tactile score at the recorded assessment.

A standardized probe provides a quantitative way to compare measured responses between groups. Using a mean across two teeth also makes the recorded subject-level result a summary of those tooth measurements rather than a separate result for each tooth. The registry does not report information about probe calibration, assessor training, repeatability, or the criteria used to select the teeth beyond describing them as hypersensitive.

The primary endpoint is a specific tactile measure at a specific time point. It does not by itself summarize air-blast sensitivity, all symptoms, or broader outcomes. The record does not describe a threshold for a clinically important change, so the statistical difference should not be equated with a stated threshold of practical importance.

7. Results Posted in the Registry

• A-Experimental Toothpatse: mean 19.81 versus 13.94 on control; difference 5.87 (95% CI 4.60 to 7.14), standardized effect d = 0.72; 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.

Air Blast Hypersensitivity (4 Week)

• 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:
  • A-Experimental Toothpatse: mean 1.61 versus 2.18 on control; difference -0.57 (95% CI -0.67 to -0.47), standardized effect d = -0.93; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for A-Experimental Toothpatse than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Air Blast Hypersensitivity (8 Week)

• 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:
  • A-Experimental Toothpatse: mean 0.89 versus 1.80 on control; difference -0.91 (95% CI -1.02 to -0.80), standardized effect d = -1.29; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically lower for A-Experimental Toothpatse than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The registry lists two secondary outcomes: air-blast hypersensitivity at 4 weeks and at 8 weeks. In both posted comparisons, the experimental arm has a lower mean than the control arm, and both unadjusted recalculations report p < 0.001. These outcomes therefore show a consistent direction in the recorded group means across the two listed time points. The record does not define the direction of the air-blast scale, so lower means should not be labeled as improvement on the basis of the registry description alone.

The secondary findings complement the primary result by adding a different measurement modality and a later assessment. The primary outcome measures tactile response at 4 weeks; the secondary outcomes concern air-blast response at 4 weeks and 8 weeks. Agreement in the relative ordering of arm means across these measures can be described, but it does not establish that they measure identical aspects of sensitivity or have interchangeable clinical meaning.

The registry also reports ANCOVA for each secondary comparison, with p = 0.05, but does not provide adjusted estimates or interval bounds. As with the primary analysis, the record does not identify the adjustment variables or provide sufficient detail to reproduce those models. The unadjusted comparisons are based on posted group summaries and should be kept distinct from the reported ANCOVA results.

Secondary outcomes generally carry less confirmatory weight than a prespecified primary outcome, particularly when several outcomes or time points are tested. Repeated testing can increase the chance of obtaining at least one apparently notable result by chance if no adjustment or testing hierarchy is used. The registry record does not report whether multiplicity was addressed, whether the secondary outcomes were prespecified in a testing sequence, or how their results were intended to support conclusions. Their p-values should therefore be read as unadjusted results, not as evidence that testing across outcomes was controlled.

The record lists four outcome measures and four analyses while naming two secondary outcomes. The descriptions of any additional measures are not reported in the registry record. This limits a full account of the outcome set and makes it difficult to assess the scope of all analyses that may have informed the study’s conclusions.

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

• Air Blast Hypersensitivity (4 Week)
• Air Blast Hypersensitivity (8 Week)

9. Statistical Interpretation

10. Statistical Methods Explained

Continuous outcomes are often summarized by an average and a measure of spread. In this trial, the registry reports means and standard deviations for the tactile outcome and the air-blast outcomes. A mean describes the center of the observed scores in a group; a standard deviation describes how dispersed those scores are around that mean. Neither quantity gives the full shape of the distribution, and they do not show whether every participant’s score was close to the average.

What does the mean difference describe?

A mean difference subtracts one group’s average from the other group’s average, using a stated comparison direction. For the primary comparison, the recalculated difference is expressed as the experimental-arm mean minus the control-arm mean. The value is positive because the experimental-arm mean is higher. The interpretation depends on the endpoint’s scale: for tactile hypersensitivity, the registry explicitly says higher scores indicate that more force was needed to elicit pain and correspond to lower hypersensitivity.

The comparison is unadjusted because it is recalculated from the posted group summaries rather than estimated from a model that accounts for other variables. An unadjusted comparison can be useful for understanding the raw group-level contrast. It does not reproduce an adjusted model when that model includes covariates or other features not represented in the summaries.

What does the interval tell readers?

An interval around an estimate conveys uncertainty about the effect size under the assumptions of the method used to construct it. A narrower interval indicates greater precision than a wider interval on the same scale. If an interval includes the value representing no difference, the data are compatible with a range that includes no difference under that calculation. If the interval lies on one side of no difference, the calculated range is directionally more consistent with a difference on that side. An interval does not show the probability that a particular true effect lies inside it, nor does it resolve whether an effect is practically important.

The unadjusted recalculation reports an interval for the primary mean difference. The registry’s ANCOVA record separately indicates a 95% confidence interval, but it does not provide that analysis’s estimate or interval bounds. The stated confidence level therefore cannot supply the missing ANCOVA precision information.

How should the p-values be read?

A p-value measures how incompatible the observed data are with a specified null model, under the assumptions of the analysis. It is not the probability that the null hypothesis is true, and it does not measure the size or importance of an effect. The unadjusted recalculation reports p < 0.001 for the primary comparison. The registry separately records p = 0.05 for its ANCOVA analysis. These values come from different analyses and should not be treated as interchangeable.

The ANCOVA method compares outcomes while accounting for variables included in the model. The registry does not identify the covariates or give the adjusted estimate, so it is not possible to explain which factors were controlled for or how adjustment affected the comparison. An adjusted result may differ from a raw comparison; assessing that difference requires the model details and its results.

Why do spread and distribution matter?

Mean-based methods are most straightforward to interpret when the data and model assumptions are reasonably suited to them. Standard deviations help convey variation, but group summaries alone do not reveal skew, outliers, unusual clustering, or whether model assumptions were checked. The registry does not report distribution checks, transformations, or sensitivity analyses. These omissions do not establish that assumptions were violated; they mean the record does not document how those issues were assessed.

For a continuous outcome, large variation within groups can make the group difference harder to estimate precisely. The standard error reflects uncertainty in an estimated quantity and depends on both variation and the amount of information available. It is not a measure of how much participants vary from one another. The recalculation uses the posted summaries and is not a replacement for the trial’s prespecified analysis.

What does ANCOVA add, and what remains unknown?

ANCOVA is a regression-based method commonly used to compare group outcomes while adjusting for selected covariates. In a randomized trial, adjustment can account for measured variables included in the model and can affect precision. The method’s meaning depends on the variables, coding, model specification, and handling of missing observations. Those details are not reported in the registry record. The registry’s stated method and p-value therefore document that an ANCOVA analysis was recorded, but do not make the model independently reproducible from the record.

The record does not report an analysis plan, missing-data procedure, treatment of protocol deviations, or the populations used for analysis. It also does not report multiplicity adjustment. These are important distinctions when interpreting a set of primary and secondary tests: the reported p-values alone do not establish whether testing was controlled across outcomes or how incomplete data were handled.

11. Confidence Intervals and Precision

The primary group summaries show means of 19.81 in the experimental arm and 13.94 in the control arm. The recalculated unadjusted mean difference is 5.87, with an interval from 4.595 to 7.145. Because this interval stays above no difference, it indicates that the simple recalculation places the mean contrast in the positive direction throughout the reported range. Its width also conveys the uncertainty around that estimate on the outcome’s scale.

Precision is not the same as importance. An interval can be relatively concentrated around an estimate while leaving open whether the effect is large enough to matter in practice. The registry does not state a clinically important difference for the tactile scale. It also does not report baseline values or a clinical threshold that would let readers interpret the difference as a threshold-level response.

The registry’s ANCOVA record gives p = 0.05 and identifies a 95% confidence interval, but the estimate and interval bounds are not reported in the registry record. Thus, the adjusted result’s precision cannot be evaluated from that entry. The recalculated interval is based on the posted summary statistics and should not be mistaken for the missing interval from ANCOVA.

Standard deviations of 9.56 and 6.42 indicate that individual scores varied within both groups. Group means and intervals describe uncertainty about a group contrast; they do not show the range of individual responses or predict a particular participant’s score. The record does not provide a distribution plot or individual-level data in the registry record for this analysis, so the extent of overlap between individual scores cannot be described.

More generally, confidence intervals are affected by the amount of information and the variability in the measurements. They are most useful when considered alongside the estimate, the scale’s direction, and the design and analysis that produced them. Here, the primary recalculation supplies an estimate and interval, while the adjusted analysis is recorded without its corresponding estimate and bounds.

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 sample-size calculation. The original design assumptions are not reported in the registry record. These 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 set at a stated fraction of the observed effect.

The entries are participants per arm, not total participants and not total events. The table considers planning for 100% of the observed effect, 75% of the observed effect, and 50% of the observed effect. For each assumed effect, the 80% power column gives the number of participants per arm indicated by the calculation for an 80% chance of detecting an effect of that size under the stated assumptions. The 90% power column gives the corresponding planning number for a 90% chance.

Power is a property of a planned design under specified assumptions. It is not a guarantee that a study will produce a statistically significant result, and it does not describe the probability that a particular finding is true. The calculations are illustrative because they use an effect observed in this trial as their starting point; observed effects can be uncertain and may not match the effect in a future study.

Smaller effects are harder to distinguish from random variation, so planning to detect a smaller fraction of the observed effect requires more participants per arm under these assumptions. Likewise, targeting 90% power rather than 80% generally requires a larger planned sample. These figures are not observed power: they are prospective sample-size illustrations, not a retrospective measure of the trial’s chance of detecting its observed result.

They also do not replace a design-specific calculation using the intended outcome, analysis, missing-data expectations, and target effect. The registry record does not report the trial’s own original planning assumptions, so the illustration should not be read as evidence about why the trial enrolled the number of participants it did.

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 = 5.870; pooled standard deviation σ = 8.148.
2. n = 2 × (1.96 + 0.842)² × 8.148² / 5.870² = 30.2, rounded up to 31 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 <- 5.87                      # observed difference in means
sigma <- 8.14772435588534                     # 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(763269)
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 = 31 (80% power), 41 (90% power)
 75% of observed effect: n per arm = 54 (80% power), 72 (90% power)
 50% of observed effect: n per arm = 121 (80% power), 162 (90% power)
power.t.test: 31.2 
Simulated power at n = 31 per arm: 0.795 (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 records an ANCOVA analysis for the primary comparison and lists p = 0.05. It also records a 95% confidence interval for that analysis, but the estimate and interval bounds are not reported in the registry record. The ANCOVA result is therefore not fully quantifiable from the posted record: its direction and adjusted effect size cannot be recovered from the p-value alone.

The unadjusted recalculation from the posted group summaries gives a mean difference of 5.87, with an interval from 4.595 to 7.145 and p < 0.001. This is a raw comparison of group means and does not substitute for the reported ANCOVA. The methods differ, and the registry does not provide enough information about the ANCOVA covariates or model specification to reconcile their estimates or p-values.

The record does not flag a discrepancy between the posted summaries and the reported analysis. That does not make the analyses identical: the recalculation remains unadjusted, while the registry identifies ANCOVA as its reported method. The sponsor’s adjusted result should be understood through the registry’s reported analysis, while the recalculation is a supplementary description of the posted summary statistics. Without the adjusted estimate and interval bounds, the size and precision of the sponsor-reported adjusted contrast remain unknown.

15. Multiplicity, Missing Data and Analysis Populations

The registry record identifies a primary endpoint and two secondary outcomes, and it lists p-values for analyses of each. It does not report whether the trial used a formal multiplicity strategy. In a study with more than one outcome or assessment time, testing each comparison separately can raise the chance of at least one small p-value occurring by chance across the set of tests. A prespecified hierarchy or an adjustment can address that issue, but neither is documented in the registry record.

The recalculated p-values for the posted group summaries are explicitly unadjusted. They describe each comparison without accounting for the other outcomes or time points. They should not be interpreted as family-wise evidence across all endpoints. The reported ANCOVA entries give p = 0.05 for the analyses, but the record does not explain whether these values were adjusted for multiplicity or how they relate to a testing plan.

Missing-data handling is also not reported in the registry record. The arm summaries include recorded group sizes, but the record does not explain whether all randomized participants contributed to each outcome, how missing measurements were handled, whether any data were imputed, or whether participants were excluded from an analysis. It is therefore not possible to determine from the record whether the analyses followed an intention-to-treat population, a per-protocol population, or another defined analysis population.

The registry does not report the number of missing measurements at each endpoint or reasons for missingness. This matters because an analysis based only on observed outcomes can be affected if missingness is related to treatment or outcome. That is a general concern, not evidence that missing data biased these results.

The four analyses listed in the record and the two named secondary outcomes also leave the full analysis set unclear. The descriptions of the other listed outcome measures are not reported in the registry record. The analysis plan, covariates in ANCOVA, handling of protocol deviations, and any interim analyses are not reported in the registry record. Without these details, the posted results support descriptive interpretation but do not allow a full audit of the prespecified statistical approach.

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 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry reports serious adverse events for the two arms. There were 0 serious adverse events among 314 participants at risk in the experimental arm and 0 among 312 participants at risk in the control arm. No serious adverse-event terms are listed. These figures describe what was recorded in the registry for the groups and should not be taken as proof that the possibility of serious adverse events is absent.

The record separately lists other adverse events affecting 3 participants in the experimental arm and 4 in the control arm, with 314 and 312 participants at risk, respectively. These are not serious-event counts in the registry’s separate serious-event fields. The record does not provide further detail about event types, timing, severity, or whether events were judged related to the toothpaste.

Deaths are not reported in the registry record. The adverse-event entries are therefore a limited account of safety information. They do not describe how events were collected, how long participants were followed for safety, or whether events led to stopping treatment. No conclusion about comparative safety beyond the recorded event counts is warranted from these summaries alone.

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

The posted results describe a difference between the arm averages on the primary tactile measure at 4 weeks. The experimental arm’s mean score was higher than the control arm’s, and the registry defines higher tactile scores as requiring more force to elicit pain and corresponding to lower hypersensitivity. The unadjusted recalculation places the average difference on the positive side of no difference, with an interval from 4.595 to 7.145 and p < 0.001.

This is a statistical description of a group comparison, not a prediction for every participant. The within-arm standard deviations show that outcomes varied. A group average does not show how many individuals experienced a particular degree of change, and the registry does not report a responder threshold or a clinically important difference. Statistical evidence of a difference and evidence that a difference is meaningful in practice are separate questions.

The record does not provide baseline outcome values, so the posted endpoint means should not be described as changes from baseline. The reported ANCOVA analysis is recorded with p = 0.05, but its adjusted estimate and interval bounds are not reported in the registry record. The unadjusted recalculation cannot fill in those missing adjusted results.

The outcomes are also limited in scope. The primary comparison concerns tactile hypersensitivity at 4 weeks. Air-blast outcomes are listed at 4 and 8 weeks, but the registry does not state their scale direction. The record does not provide a longer-term tactile result, details of the participant population, or a full account of missing data and analysis populations. The results should therefore be interpreted as findings for the recorded measures, groups, and assessment times—not as a conclusion about every symptom, population, or duration.

In short, the posted summaries show a clear unadjusted separation in the primary group means in the scale direction defined by the registry. They do not establish the clinical importance of that separation, supply the missing details of the adjusted analysis, or resolve the limitations in the registry’s descriptions of outcomes and methods.

18. Why This Trial Matters Statistically

This trial illustrates why the direction and definition of an endpoint are essential to interpreting a mean difference. The tactile scale is not described simply as “more sensitivity” when the score rises: the registry explains that a higher score means more force was needed to elicit pain and corresponds to lower hypersensitivity. Reading the sign of the difference without that information could reverse its meaning.

It also illustrates the distinction between a raw comparison and a model-based analysis. The posted arm means and the unadjusted recalculation make the group contrast transparent. The registry separately reports ANCOVA, but omits the adjusted estimate, interval bounds, and covariates. Readers can therefore see a useful descriptive comparison while still recognizing that the trial’s reported adjusted result cannot be fully evaluated from the record.

Precision matters alongside statistical significance. The recalculated interval conveys a range of values compatible with the simple comparison under its calculation, while the p-value summarizes evidence against a null model. Neither tells readers whether the difference is important to patients. The record gives no clinical-importance threshold, reinforcing the need to distinguish a statistical contrast from a judgment about practical meaning.

The multiple outcomes and time points also show why a testing plan matters. Primary and secondary analyses have different roles, and the registry does not report how multiplicity was handled. Without that information, unadjusted secondary p-values should be interpreted cautiously rather than treated as a single confirmatory body of evidence.

Finally, the record separates observed trial results from planning illustrations. The sample-size calculations use fractions of the observed effect and specified assumptions; they do not reveal the trial’s original design rationale or measure its observed power. This distinction is useful when reading trial results because planning figures answer a different question from the analysis of completed outcomes.

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 registry record leaves important details of the trial population unreported. It names dentin hypersensitivity as the condition and lists enrollment of 626, but does not provide fuller eligibility criteria, baseline characteristics, or a description of how participants were recruited. The degree to which the recorded participants represent other populations cannot be assessed from these registry entries.

Important operational details are also absent. The record does not describe the randomization sequence, allocation concealment, who was masked, toothpaste instructions, adherence, or follow-up procedures. It identifies the study as randomized and double-masked, but does not supply the details needed to assess how those design features were implemented.

The primary outcome description specifies the probe, the force-based score, and the mean of two hypersensitive teeth. It does not report assessor procedures, measurement repeatability, tooth-selection rules beyond hypersensitivity, or baseline endpoint values. The registry also does not state a clinically important difference for the scale. These gaps limit interpretation of measurement quality and clinical importance.

The statistical record is incomplete. ANCOVA is named, but its covariates and adjusted estimates are not reported in the registry record. The analysis populations, missing-data procedures, multiplicity strategy, and prespecified statistical plan are also not reported. The posted unadjusted recalculations are informative summaries, but cannot replace those missing analysis details.

The record names two secondary outcomes while listing four outcome measures and four analyses. The descriptions of any additional measures are not reported in the registry record. Safety information is limited to recorded serious and other adverse-event counts; event details, collection methods, follow-up duration for safety, and deaths are not reported in the registry record. These limits constrain both efficacy and safety interpretation to the information recorded.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: The Efficacy of a Toothpaste to Reduce Sensitivity — NCT00763269.
• Registry record last updated 2012-03-07; status last verified 2011-06.
• Results first posted 2010-09-17.
• 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 identifies a completed Phase 3, randomized, double-masked, parallel-group trial of a sensitive toothpaste and a Triclosan control toothpaste for dentin hypersensitivity. Enrollment is listed as 626. The primary endpoint was mean tactile hypersensitivity measured with a Yeaple Probe at 4 weeks; higher scores were defined as requiring more force to elicit pain and corresponding to lower hypersensitivity.

The experimental arm’s primary mean was 19.81, compared with 13.94 in the control arm. The unadjusted recalculation gives a mean difference of 5.87, an interval from 4.595 to 7.145, and p < 0.001. The registry also records ANCOVA with p = 0.05, but does not report its adjusted estimate or interval bounds.

Air-blast outcomes were recorded at 4 and 8 weeks. The record does not report the multiplicity approach, missing-data handling, analysis populations, ANCOVA covariates, or the trial’s original sample-size assumptions. Serious adverse-event counts were 0 in each arm; further safety detail is limited.