Chewing and Oral Processing of Solid Food: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Chewing and Oral Processing of Solid Food (NCT05594173), a registered phase not stated study. The primary outcome is Number of Chewing Cycles Per Bolus.

2. Clinical Question

3. Trial Design

The registry record identifies this project as “Chewing and Oral Processing of Solid Food in Healthy Swallowing.” It lists University Health Network, Toronto as the sponsor, an enrollment of 20, a start date of 2019-09-13, a primary completion date of 2020-12-20, and a status of COMPLETED. These are record details; they do not, by themselves, describe how participants were assigned to foods or how the measurements were conducted.

The project description says its overall goal was to collect measurements of food bolus transit through the oropharynx during chewing, oral processing and swallowing. It notes that food texture modification is commonly used for people with dysphagia, while the way this intervention works is not properly understood. The named intervention is food texture modification, listed as type OTHER. Specific textures, the sequence in which bolus types were tested, and any comparator procedure are not reported in the registry record.

The registry explicitly characterizes the study as not a randomized comparison, with allocation not stated, and cautions that arms are not a like-for-like control comparison. Therefore, the record does not support treating any arms as exchangeable treatment and control groups. Whether participants received one or more bolus types, and whether the measurements were paired within participants, is not reported in the registry record.

The primary outcome is continuous: the mean number of chewing cycles per bolus, with standard deviation as the stated measure of dispersion. Its timeframe is baseline at a single timepoint. The record lists two outcome measures but no analyses. A detailed protocol, statistical analysis plan, sample-size justification, and information about interim analyses are not reported in the registry record.

4. Participant Flow and Accounting

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

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Data for 3 additional participants could not be analyzed due to poor electromyography signal quality.

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 Number of Chewing Cycles Per Bolus, measured over Baseline (single timepoint only).

The primary endpoint is the number of chewing cycles per bolus. The registry says that surface electromyography, or sEMG, of the masseter muscle is used to count muscle-contraction spikes during chewing. The measurement is specified for a single comfortable bite of each bolus type, at baseline and at a single timepoint. The outcome is treated as a continuous measure, summarized as a mean with standard deviation.

As a general measurement concept, counting muscle-contraction signals offers a way to describe chewing activity in a form that can be summarized across observations. The count may be relevant to a broader investigation of how food texture relates to oral processing and bolus transit. That rationale is consistent with the project description, which focuses on collecting measurements during chewing, oral processing and swallowing. It does not establish that chewing cycles alone capture every aspect of swallowing or bolus movement.

The record does not report the observed mean, standard deviation, participant-level distribution, or a comparison between bolus types for this endpoint. It also does not describe the bolus types or provide further details about signal processing, rules for identifying a contraction spike, or handling of repeated measurements. Data for 3 additional participants could not be analyzed due to poor electromyography signal quality. Without numerical endpoint results and more detail about the measurement process, the registry record supports describing the intended measure, but not quantifying the observed chewing pattern.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a mean summarize?

For a continuous measure, a mean is a summary of the average value across the observations included in the calculation. In this study, the recorded quantity is the number of chewing cycles per bolus, and the registry specifies the mean as the outcome parameter. A mean can be useful when the scientific question concerns an average level of chewing activity, but it does not show the range of individual observations or whether values cluster tightly or vary substantially. The registry record does not report the mean for the primary endpoint, so its value cannot be interpreted.

The record specifies standard deviation as the measure of dispersion. In general, standard deviation describes the spread of observations around their mean, using the same measurement scale as the original outcome. It is not a measure of uncertainty in the mean itself. A confidence interval, if reported, would instead describe uncertainty around an estimated quantity under the assumptions of the analysis. No confidence interval for the primary endpoint is reported in the registry record.

Why does the measurement method matter?

The endpoint is based on surface electromyography of the masseter muscle. The registry describes counting muscle-contraction spikes as chewing cycles. A statistical summary is only as interpretable as the measurement that feeds it: consistent signal acquisition and clear rules for identifying spikes matter because inconsistent measurement can add noise or produce systematic differences. The registry states that data for 3 additional participants could not be analyzed due to poor electromyography signal quality. More detail about signal-quality thresholds, how spikes were classified, or whether assessors were blinded is not reported in the registry record.

Measurement error can affect precision by making observations more variable. It can also affect comparisons if the quality or interpretation of signals differs across bolus types. These are general measurement considerations, not findings about this study. The record does not provide enough information to determine whether signal quality was comparable across conditions or whether the unavailable measurements were systematically different from analyzed ones.

What can a comparison establish?

A comparison needs clearly defined groups or conditions and a suitable analysis. Here, the registry notes that the study is not a randomized comparison, allocation is not stated, and arms are not a like-for-like control comparison. Random allocation, as a general design principle, can help balance measured and unmeasured participant characteristics between groups. When allocation is not randomized or is not described, differences between groups may reflect more than the condition being compared. This matters especially when interpreting a contrast as an intervention effect.

The primary endpoint refers to a comfortable bite of each bolus type, but the registry does not identify the types, describe their order, or explain whether participants contributed repeated measurements across types. If measurements were paired within participants, a method that accounts for within-person dependence could be appropriate; if they were independent, a different approach might be needed. This is a general statistical distinction. The registry record does not report which structure applied or which model was used, and it lists no analyses.

Why does variability matter?

Variability affects how precisely an average or contrast can be estimated. Greater variability generally makes an estimate less precise when other design features are unchanged; lower variability generally allows greater precision. A confidence interval is a general tool for expressing uncertainty around an estimate. It indicates a range of values compatible with the data and the assumptions of the statistical procedure, rather than guaranteeing that the true value lies within that range. No estimate or confidence interval for the primary outcome is reported in the registry record, so precision cannot be assessed from the primary results.

Group size also affects precision, but the enrollment figure alone does not establish how many observations contributed to a particular endpoint or comparison. The record states enrollment of 20 and separately notes that data for 3 additional participants could not be analyzed because of poor signal quality. It does not report an analyzed sample size for the primary outcome. Those details should not be converted into an assumed analysis denominator.

What do the planning assumptions mean?

The registry describes sample-size planning illustrations based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect. These are planning assumptions, not a description of the study's own design or evidence that a particular effect was detected. The registry record does not report the observed effect estimate underlying those illustrations, nor does it report that the study used equal allocation or a two-arm randomized design.

In general, a significance level is a threshold used in a specified testing procedure to control the chance of a false-positive conclusion under its assumptions. A two-sided test allows evidence in either direction to count against the null hypothesis. A normal approximation uses a mathematical distribution to approximate the sampling behavior of an estimate; its suitability depends on the data and design. These general explanations do not establish that any test was carried out in this study. The registry lists no analyses, and its planning illustrations are not observed power.

Sample-size planning asks how much information a future study might need for a target level of precision or ability to detect a prespecified effect under chosen assumptions. A calculation based on an observed effect can be sensitive to how large or small that initial estimate happens to be. Planning for a fraction of an observed effect explores alternative target effects; it does not change the observed study result. The registry's description does not provide the numerical effect fractions or the resulting sample-size values in this record.

Why would over-dispersion matter?

As a general concept, over-dispersion occurs when observed variability exceeds what a model assumes. If a model understates variability, standard errors can be too small and uncertainty intervals can be too narrow. This issue is relevant to some count-data models, but the primary outcome is described as a continuous measure summarized by a mean and standard deviation. The registry does not report a count model, a variance assumption, or an over-dispersion assessment. It would therefore be inappropriate to say that over-dispersion was present or that a particular correction was used.

Overall, the record gives a short description of the endpoint and its measurement, but not the statistical analysis details needed to reproduce or evaluate an inferential result. The analysis model, treatment of repeated measurements, covariate adjustment, handling of missing observations, confidence intervals, and hypothesis tests are not reported in the registry record. Statistical concepts can clarify what such information would mean, but they cannot replace the missing results or analysis specification.

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("Healthy Participants: Carrot", "Healthy Participants: Cracker", "Healthy Participants: Cracker With Barium Paste", "Healthy Participants: Gummy Candy", "Healthy Participants: Minced and Moist Barium Stim", "Healthy Participants: Soft and Bite-sized Barium S")
n   <- c(14, 14, 14, 14, 14, 14)
m   <- c(22, 15, 15, 28, 6, 11)
sp  <- c(11, 6, 4, 13, 3, 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  Healthy Participants: Carrot  14  22.000  11.000  15.649  28.351
CARM  Healthy Participants: Cracker  14  15.000  6.000  11.536  18.464
CARM  Healthy Participants: Cracker With Barium Paste  14  15.000  4.000  12.690  17.310
CARM  Healthy Participants: Gummy Candy  14  28.000  13.000  20.494  35.506
CARM  Healthy Participants: Minced and Moist Barium Stim  14  6.000  3.000  4.268  7.732
CARM  Healthy Participants: Soft and Bite-sized Barium S  14  11.000  4.000  8.690  13.310

11. Multiplicity, Missing Data and Analysis Populations

The registry lists two outcome measures, but the available record does not describe the full set of hypotheses, identify which outcome was primary beyond the named primary measure, or report an adjustment for multiple comparisons. Multiplicity arises when several outcomes, groups, timepoints, or contrasts are tested: the chance of at least one false-positive result can increase when many tests are considered. As a general approach, studies may specify a primary contrast in advance or use methods that account for multiple testing. Whether either approach was used is not reported in the registry record.

The primary outcome is specified at baseline at a single timepoint, so the registry does not describe repeated follow-up timepoints for that endpoint. It does refer to a comfortable bite of each bolus type, but the number and identity of bolus types and the intended comparisons are not reported in the registry record. The number of possible contrasts therefore cannot be established from the available description.

For missing data, the record states that data for 3 additional participants could not be analyzed because of poor electromyography signal quality. It does not report how missing or unusable observations were treated in the analysis, whether other observations were missing, or whether any sensitivity analysis was conducted. In general, excluding observations can affect interpretation if the reasons for exclusion are related to the measured outcome or conditions being compared. The available information does not establish whether that concern applies.

The analysis populations are not defined. The registry does not report whether the endpoint was analyzed for all enrolled participants, only participants with usable signals, or another defined group. Although the record gives enrollment of 20, that figure alone should not be taken as the denominator for the primary analysis. The registry lists no analyses, and the statistical plan, analysis population definitions, and missing-data assumptions are not reported in the registry record.

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.

Most frequent non-serious adverse event terms

The adverse-event record identifies a group titled Healthy Participants. It lists 18 at risk for serious adverse events, with 0 affected, and 18 at risk for other adverse events, with 1 affected. Deaths are listed as 0. No serious adverse event terms are listed. These are the recorded counts and categories; they do not provide a detailed account of event type, timing, severity within the other-adverse-event category, or relationship to the intervention.

Serious and other adverse events are separate registry categories, and the counts should not be combined. The record does not explain why the at-risk counts are as listed or how they relate to the enrollment figure. It also does not state whether all events were actively collected, how long participants were monitored, or whether the event recorded in the other-adverse-event category was considered related to food texture modification.

Zero affected participants in the serious category means no serious adverse event was recorded for that listed group in the registry entry; it is not proof that serious events are impossible or that every potential harm was assessed. Likewise, the other-adverse-event count should not be interpreted as a complete estimate of risk without information on event definitions, observation time, and collection procedures. These figures are descriptive safety information, separate from the primary chewing-cycle outcome.

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

The registry record identifies a question about measuring chewing activity during oral processing of solid food. It describes a primary endpoint based on masseter-muscle sEMG, with contraction spikes counted as chewing cycles for a comfortable bite of each bolus type. The project description places these measurements in a broader effort to understand food bolus transit through the oropharynx during chewing, oral processing and swallowing.

The numerical primary outcome is not reported in the registry record. There is therefore no reported average cycle count, measure of spread, estimate of a contrast, or interval expressing its precision. The record cannot establish the observed pattern of chewing cycles across bolus types or how consistently the measure was obtained. It also cannot support a conclusion about the size or direction of a difference.

The record does not describe a randomized comparison and explicitly cautions that arms are not a like-for-like control comparison. Consequently, it does not provide a basis for attributing any possible difference to food texture modification. A descriptive measurement study can contribute information about how a physiological process is measured, but a causal claim requires a design and analysis that address alternative explanations. The relevant design and analysis details are not reported in the registry record.

The project is framed around a gap in understanding, not as a reported test of a clinical outcome. The registry does not report patient-centered swallowing outcomes, a comparison of clinical strategies, or a numerical result showing how texture modification changes swallowing. The listed intervention alone does not establish that participants received a particular texture-modification procedure or that any treatment effect was evaluated.

Thus, what the registry supports is a description of the intended measurement, project purpose, enrollment, dates, and limited adverse-event counts. It does not provide the primary result needed to judge the amount of chewing activity measured or its uncertainty. The planning illustrations described in the record are not observed power and should not be read as evidence of a study finding. The result does not establish benefit, lack of benefit, or safety for people with dysphagia.

14. Why This Trial Matters Statistically

This study is statistically relevant because it focuses on an intermediate physiological measurement rather than reporting a direct clinical comparison. Counting chewing cycles from sEMG is a way to turn muscle activity during oral processing into a measurable endpoint. A clear operational definition can help readers understand what a statistical summary represents. The registry supplies a brief definition—counting contraction spikes for a comfortable bite—but does not report the detailed signal-processing rules needed to assess reproducibility.

The study also highlights the distinction between enrollment and analyzable data. The record lists enrollment of 20 and states that data for 3 additional participants could not be analyzed because of poor signal quality. These registry entries make measurement feasibility and data availability relevant to interpretation. Without an analysis denominator, however, readers cannot determine how many observations contributed to the primary estimate or whether unusable signals were distributed similarly across bolus types.

Study design is equally important. The registry says this is not a randomized comparison and that arms are not a like-for-like control comparison. That warning helps prevent a descriptive difference from being mistaken for a causal effect. The scientific context concerns food texture modification and swallowing, but a mechanistic measurement does not, by itself, show whether a clinical intervention changes outcomes that matter to patients.

Finally, the record illustrates why numerical results and uncertainty measures are essential. A named endpoint is not enough to assess its magnitude, variability, or precision. The registry lists no analyses and does not report the primary outcome estimate. Its planning description is not a substitute for an observed result. These distinctions matter when interpreting a completed study and when deciding what questions future measurement or comparative studies would need to address.

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 immediate limitation is that the registry record does not report the numerical result for the primary endpoint. It describes the mean and standard deviation as the intended summaries, but gives neither value. No primary-outcome contrast, confidence interval, or test result is reported. The registry lists no analyses, so the posted record does not permit an assessment of the magnitude or precision of the endpoint.

The design information is limited. The record states that this is not a randomized comparison, says allocation is not stated, and warns that arms are not a like-for-like control comparison. It does not describe a comparator, the bolus types, their order, or whether observations were repeated within participants. These gaps prevent a clear account of which measurements could be compared and what a difference would mean.

Measurement and data availability also require caution. Data for 3 additional participants could not be analyzed because of poor electromyography signal quality. The registry does not report the signal-quality criteria, whether any other data were missing, how unavailable measurements were handled, or the number of observations included in the endpoint analysis. It is therefore not possible to assess the effect of these unavailable measurements on the reported result, particularly because no numerical result is posted.

The record lists two outcome measures but does not report a statistical analysis plan, details of multiplicity handling, adjustment methods, or analysis-population definitions. The project description gives a broad purpose but does not specify how bolus transit was measured beyond the primary chewing-cycle description. The adverse-event record provides limited category counts without event details or monitoring procedures. These are limitations of the information reported in the registry record; they should not be treated as proof that unreported procedures or analyses did or did not occur.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Chewing and Oral Processing of Solid Food — NCT05594173.
• Registry record last updated 2022-11-21; status last verified 2022-10.
• Results first posted 2022-11-21.
• 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

The record is for NCT05594173, titled “Chewing and Oral Processing of Solid Food,” with the official title “Chewing and Oral Processing of Solid Food in Healthy Swallowing.” University Health Network, Toronto is listed as sponsor. The registry gives an enrollment of 20, a start date of 2019-09-13, a primary completion date of 2020-12-20, and a status of COMPLETED.

The project aimed to collect measurements of food bolus transit through the oropharynx during chewing, oral processing and swallowing. Its primary endpoint is the mean number of chewing cycles per bolus, measured using masseter-muscle sEMG at baseline at a single timepoint. Data for 3 additional participants could not be analyzed because of poor signal quality.

The registry identifies the study as not a randomized comparison and notes that allocation is not stated and arms are not a like-for-like control comparison. It lists two outcome measures and no analyses. The numerical primary endpoint result and the statistical analysis details are not reported in the registry record. The adverse-event entry lists 0 serious adverse events among 18 at risk, 1 other adverse event among 18 at risk, and 0 deaths.