DDK Acoustic Analysis and Swallowing Indicators (AAP-DDK)

Acoustic Analysis of Performance in Diadochokinetic (DDK) Tasks and Swallowing Function Indicators Among Adults Across Different Age Groups

This study examines whether simple speech tasks and a swallowing screening test can help identify swallowing risk in adults of different ages. Participants will complete basic questions, a swallowing self-assessment, a saliva swallowing test, and short voice recordings of rapid syllables. The study is non-invasive, takes about 75 minutes, and may help develop an easy, low-cost screening tool for early swallowing problems.

Study Overview

• Status: Not yet recruiting
• Conditions: Dysphagia; Swallowing Function; Swallowing Risk

Detailed Description

This is a cross-sectional observational study examining the relationship between diadochokinetic (DDK) speech performance and swallowing function in community-dwelling adults aged 18 years and older. Participants will complete a single study visit, during which demographic and health-related information will be collected, the EAT-10 swallowing self-assessment will be administered, the Repetitive Saliva Swallowing Test (RSST) will be performed, and short DDK speech recordings of /pa/, /ta/, and /ka/ will be obtained in a quiet setting. Acoustic features will be extracted from the recordings and analyzed together with RSST and EAT-10 results to explore age-related differences and to develop a predictive screening model for swallowing risk. All data will be de-identified, securely stored, and retained according to study requirements.

• Study Type: Observational
• Enrollment (Estimated): 720

Contacts and Locations

• Study Contact: Name: HUNG C F Kaohsiung Medical University, MASTER; Phone Number: #2646 #614 +8867-3121101; Email: gabino00076@gmail.com

Study Locations

• Taiwan
  • Taiwan
    • Kaohsiung City, Taiwan, Taiwan, 807
      • Department of Sports Medicine, Kaohsiung Medical University, Taiwan
      • Contact: C F HUNG, MASTER; Phone Number: #2646 #624 +8867-3121101; Email: gabino00076@gmail.com
      • Contact: L Y GUO Professor and Dean of the college of Health Sciences, Doctorate; Phone Number: #2646 #624 +8867-3121101; Email: yuen@kmu.edu.tw
      • Sub-Investigator: C F HUNG, Master

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

The study population consists of community-dwelling adults aged 18 years and older, with no upper age limit, who are able to communicate in Mandarin or Taiwanese, provide informed consent, and complete DDK tasks, RSST, and EAT-10 assessment. Participants will be recruited from community organizations and related settings in the Kaohsiung-Pingtung region. The study uses a single-visit observational design with age-based subgroup analyses and no intervention.

Description

Inclusion Criteria:

• 1.Community-dwelling adults aged 18 years or older, with no upper age limit.
• 2.Ability to communicate in Mandarin or Taiwanese and understand the study procedures.
• 3.Willingness to provide written informed consent.
• 4 .Ability to complete the DDK tasks and RSST.

Exclusion Criteria:

• 1.Presence of acute respiratory infection, upper respiratory inflammation, or other acute conditions that may significantly affect speech or swallowing.
• 2.Impaired consciousness, significant cognitive deficits, or inability to understand the study procedures.
• 3.Recent surgery or radiotherapy involving the oral cavity or pharynx that affects speech or swallowing.
• 4.Severe hearing impairment that prevents understanding of instructions.
• 5.Any other condition deemed unsuitable for participation by the investigators.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Age-Based Cohort; Community-dwelling adults aged 18 years and older who complete a single study visit including demographic questionnaire, EAT-10, RSST, and DDK speech recordings. This is an observational cohort with no intervention, and data will be analyzed by age group.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Repetitive Saliva Swallowing Test Classification	Classification of swallowing function based on the Repetitive Saliva Swallowing Test (RSST). Participants will be classified as having normal RSST performance if they complete greater than or equal to 3 swallows in 30 seconds, and abnormal RSST performance if they complete fewer than 3 swallows in 30 seconds.	Day 1

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Eating Assessment Tool-10 Total Score	Total score on the Eating Assessment Tool-10 (EAT-10), a 10-item self-report questionnaire used to assess swallowing-related symptoms. The total score ranges from 0 to 40, where higher scores indicate worse swallowing-related symptoms. A score of 3 or higher suggests possible swallowing difficulty.	Day 1
Diadochokinetic Speech Rate	Rate of repeated diadochokinetic speech productions of /pa/, /ta/, and /ka/. The rate will be reported as syllables per second.	Day 1
Diadochokinetic Speech Fundamental Frequency	Fundamental frequency (F0) extracted from repeated diadochokinetic (DDK) speech recordings of /pa/, /ta/, and /ka/. Fundamental frequency will be reported in Hertz (Hz).	Day 1
Diadochokinetic Speech First Formant Frequency	First formant frequency (F1) extracted from repeated diadochokinetic (DDK) speech recordings of /pa/, /ta/, and /ka/. F1 reflects the first resonance frequency of the vocal tract and will be reported in Hertz (Hz).	Day 1
Diadochokinetic Speech Second Formant Frequency	Second formant frequency (F2) extracted from repeated diadochokinetic (DDK) speech recordings of /pa/, /ta/, and /ka/. F2 reflects the second resonance frequency of the vocal tract and will be reported in Hertz (Hz).	Day 1
Diadochokinetic Speech Jitter	Jitter extracted from repeated diadochokinetic (DDK) speech recordings of /pa/, /ta/, and /ka/. Jitter reflects short-term cycle-to-cycle variability in fundamental frequency and will be reported as a percentage.	Day 1
Diadochokinetic Speech Shimmer	Shimmer extracted from repeated diadochokinetic (DDK) speech recordings of /pa/, /ta/, and /ka/. Shimmer reflects short-term variability in voice amplitude and will be reported in decibels (dB).	Day 1
Diadochokinetic Speech Harmonics-to-Noise Ratio	Harmonics-to-noise ratio (HNR) extracted from repeated diadochokinetic (DDK) speech recordings of /pa/, /ta/, and /ka/. HNR reflects the ratio of periodic harmonic energy to noise energy in the voice signal and will be reported in decibels (dB).	Day 1
Diadochokinetic Speech Root Mean Square Amplitude	Root mean square (RMS) amplitude extracted from repeated diadochokinetic (DDK) speech recordings of /pa/, /ta/, and /ka/. RMS amplitude reflects the average acoustic energy of the speech signal and will be reported in normalized amplitude units.	Day 1
Diadochokinetic Speech Zero-Crossing Rate	Zero-crossing rate (ZCR) extracted from repeated diadochokinetic (DDK) speech recordings of /pa/, /ta/, and /ka/. ZCR reflects the rate at which the speech signal changes sign over time and will be reported as the number of zero crossings per second.	Day 1

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Participant Age	Age of participants collected at baseline, reported in years.	Day 1
Participant Sex	Sex of participants collected on Day 1, reported as male or female according to the study case report form.	Day 1
Education Level	Highest level of education completed by participants collected at baseline, categorized as primary school or below, junior high school, senior high school, or college or above.	Day 1
Body Mass Index	Body mass index (BMI) calculated from measured height and weight at baseline. Height will be measured in meters and weight in kilograms; BMI will be reported in kg/m².	Day 1
Dentition Status	Dentition status of participants collected at day 1, categorized as natural dentition, partial denture, full denture, or other.	Day 1
Dry Mouth Frequency	Self-reported frequency of dry mouth symptoms collected at day 1, categorized as never, occasionally, frequently, or always.	Day 1
Smoking History	Self-reported smoking history collected at baseline, categorized as never smoker, former smoker, or current smoker.	Day 1
Medical History	Self-reported medical history collected at day 1 and categorized as none, hypertension, hyperglycemia, hyperlipidemia, or gastrointestinal disease (such as gastroesophageal reflux disease).	Day 1

Collaborators and Investigators

• Sponsor: Kaohsiung Medical University
• Investigators: Study Chair: GUO L Y Professor and Dean of the College of Health Sciences, Departme, Ph. D., Department of Sports Science, Kaohsiung Medical University, Taiwan

Study record dates

Study Major Dates

• Study Start (Estimated): June 15, 2026
• Primary Completion (Estimated): April 9, 2030
• Study Completion (Estimated): April 9, 2030

Study Registration Dates

• First Submitted: May 22, 2026
• First Submitted That Met QC Criteria: May 29, 2026
• First Posted (Actual): June 4, 2026

Study Record Updates

• Last Update Posted (Actual): June 4, 2026
• Last Update Submitted That Met QC Criteria: May 29, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Dysphagia; Older Adults; Acoustic Analysis; Swallowing Function; EAT-10; diadochokinetic; Repetitive Saliva Swallowing Test
• Additional Relevant MeSH Terms: Digestive System Diseases; Gastrointestinal Diseases; Esophageal Diseases; Otorhinolaryngologic Diseases; Pharyngeal Diseases; Deglutition Disorders
• Other Study ID Numbers: KMUHIRB-F(II)-20260160 (Other Identifier: IRB of KMUH)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data collected during the trial, including baseline characteristics, intervention-related measures, and outcome data, will be shared with a data dictionary.
• IPD Sharing Time Frame: De-identified individual participant data (IPD) and supporting information will be available starting 2 years after publication of the primary study results and will remain accessible for 5 years.
• IPD Sharing Access Criteria: De-identified individual participant data and related supporting documents will be made available only to qualified researchers affiliated with academic institutions, medical organizations, or public health agencies. Requesters must submit a detailed research proposal and evidence of ethical approval. Access will be granted subject to approval by the study team.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No