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.

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.

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.

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.

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.

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.

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.