Rehabilitation Treatment Specification System: Reliability and Dosage of Common Ingredients in Standard-of-Care Therapy for Vocal Hyperfunction

PURPOSE: The Rehabilitation Treatment Specification System (RTSS) is a theory-driven framework for identifying the active ingredients of rehabilitation treatments and was used to create standard labels in voice therapy (RTSS-Voice). The RTSS and RTSS-Voice have high validity, but reliability has not been tested. This study evaluated if RTSS-Voice ingredients can be reliably coded in standard-of-care voice therapy videos and used to identify commonalities and differences in ingredient dosage across five expert voice clinicians from different institutions. METHOD: Five speech-language pathologists from different institutions videotaped one voice therapy session for 36 patients with vocal hyperfunction. Two trained graduate students coded sessions using four RTSS-Voice ingredients: (a) opportunities to practice voicing, (b) feedback, (c) volition ingredients, and (d) vocal hygiene information. Twelve sessions were double coded for interrater reliability. RESULTS: Practice voicing codes achieved strong to almost perfect reliability (κs: .80-.95), while informational codes achieved moderate-to-strong reliability (κs: .61-.87). All clinicians spent more time on volition ingredients (14-34 min/52.4%-65.7% of the session) compared to practice voicing (3-8 min/6.3%-23.3% of the session) and feedback (3-11 min/10.8%-19.1% of the session). For practice voicing, clinicians incorporated modified airflow and resonance into over 70% of their practice and spent more time in nonspeech and structured speech compared to spontaneous speech practice. Clinicians differed in delivering volitional information and feedback directly versus indirectly. CONCLUSIONS: Multiple RTSS-Voice ingredients were reliable across raters, indicating that, with appropriate training, these are readily observable clinician actions that can aid in the study of dosage in voice therapy. The RTSS and RTSS-Voice also identified commonalities and differences in ingredient usage across multiple expert clinicians. Future work could use the RTSS and RTSS-Voice to investigate relationships between variations in therapy ingredients and individual patient outcomes. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.32785938.