Multi-Informant Oral Diadochokinesis Assessment in Mandarin-Speaking Children and Adolescents: Protocol for a Cross-Sectional Observational Study

Abstract Background Oral diadochokinesis (oral-DDK) measures rapid, accurate repetition of syllables or syllable sequences and is widely used in speech motor assessment. Its interpretation requires attention to task demands and medical or physiological factors, as well as possible correspondence with everyday speech. Objective This study aims to estimate task-, age-, and sex-related patterns in correct oral-DDK rate among Mandarin-speaking children and adolescents aged 8 to 17 years; examine associations with medical and physiological measurements; and assess correspondence with parent and teacher observations of everyday speech. Methods A dedicated cross-sectional school study was conducted in Suzhou, Anhui Province, China, from October 2024 to June 2025. Schools were randomly selected, and homeroom teachers invited eligible students from all classes. The 7-stimulus battery comprised conventional alternating motion rate, nonword sequential motion rate (SMR), and Mandarin real-word SMR. All completed performances were digitally recorded. A total of 3 professional modules documented medical and physiological background, task readiness, and 5 oromotor actions. Physicians measured height, weight, and forced vital capacity, and BMI was calculated. Speech-language pathologists administered the readiness and oromotor checks. Readiness included a brief comprehension check using 5W1H (What, Why, Who, When, Where, and How) prompts. Primary guardians and homeroom teachers each completed 3 frequency items about inaccurate speech sounds and speech perceived as too fast or too slow. Eligibility and recording usability determined the analyzable observations. A repeated-task mixed model was used to estimate rate patterns; medical, physiological, and contextual report associations will be examined separately. Results Field data collection ended in June 2025. Of 1036 participants, 2 (0.2%) withdrew, 6 (0.6%) experienced technical failures, and 2 (0.2%) could not complete the required screening or oral-DDK procedures; 1026 (99%) participants were retained. Oral-DDK scoring and verification and the primary rate analyses were completed by September 2026. As of October 2026, analyses linking rate to parent and teacher reports had not begun. A major revision of the normative manuscript was completed in early October 2026, but its publication timing is not yet known. This protocol does not present inferential results. Conclusions The protocol links conventional and real-word oral-DDK with separately recorded health, physiological, and everyday speech observations. It specifies how these records enter analyses of correct rate and preserves a standardized digital audio corpus for scoring checks and subsequent task-specific analyses.